JP3380133B2 - Novel nitrile hydratase - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to Pseudonocardia thermophila ( Pseudonocardia).
thermophila JCM3095, hereinafter simply referred to as Pseudonocardia thermophila ), a novel amino acid sequence encoding the α-subunit and β-subunit of nitrile hydratase, Regarding gene sequences. Furthermore, a recombinant plasmid containing the gene, a transformant strain transformed with the recombinant plasmid, a method for producing nitrile hydratase using the transformant strain, and a culture obtained by culturing the transformant strain The present invention relates to a method for producing a corresponding amide compound from a nitrile compound using a liquid, a bacterial cell, or a treated bacterial cell product.

[0002]

2. Description of the Related Art A technique for producing a corresponding amide compound by hydrating a nitrile group of a nitrile compound to convert it to an amide group is a chemical method in which heat treatment is performed in the presence of an acid or an alkali or in the presence of a copper catalyst. Was previously known. on the other hand,
Recently, a nitrile hydratase, which is an enzyme having a nitrile hydration activity for hydrating a nitrile group and converting it to an amide group, has been discovered, and a corresponding amide compound is obtained from a nitrile compound by using the enzyme or a microbial cell containing the enzyme. Has already been disclosed (Japanese Patent Publication No. 56-1791).
8, 62-21519, 62-31914, 59.
-37951, Japanese Patent Publication No. 4-4873, 6-5514
8). This manufacturing method is known to have advantages such as high conversion and selectivity of a nitrile compound to a corresponding amide compound as compared with conventional chemical methods.

In order to industrially produce an amide compound from a nitrile compound using nitrile hydratase, it is important to reduce the production cost of the enzyme in the production cost of the amide compound. More specifically, the unit Microbial weight, production rate of amide compound per unit time (hereinafter,
It is necessary to increase the cell activity). Therefore, attempts are being made to clone the gene of the enzyme for the purpose of expressing the enzyme in a large amount by a genetic engineering method using the gene of the enzyme. For example, genus Corynebacterium (JP-A-2-119778), genus Pseudomonas (JP-A-3-251184), Rhodococcus sp. Kaihei 6-303971) can be mentioned. However, in the case of Rhodococcus spp. Of Corynebacterium spp. And Rhodococcus spp., It was reported that the nitrile hydratase activity of the transformant strain of E. coli was extremely weak (TIBTE
CH Vol. 10, pp402-408, 1992
However, it was not always possible to obtain transformed bacterial cells having high bacterial activity by using genetic engineering techniques.

[0004]

The present inventors isolated the nitrile hydratase gene from Pseudonocardia thermophila JCM3095, which was found by the present inventors as a microorganism having nitrile hydratase activity, and isolated its amino acid sequence. Moreover, the inventors have succeeded in clarifying the gene sequence for the first time, and have succeeded in producing a gene recombinant strain that expresses the gene in a large amount, thus completing the present invention.

That is, an object of the present invention is to provide an amino acid sequence and a gene sequence of nitrile hydratase derived from Pseudonocardia thermophila.
Furthermore, a recombinant plasmid containing the gene, a transformant strain containing the recombinant plasmid, a method for producing the enzyme using the transformant strain, and a method for producing a corresponding amide compound from a nitrile compound using the transformant strain Is to provide.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be outlined below. The nitrile hydratase of the present invention is basically composed of the amino acid sequences shown in SEQ ID NOS: 1 and 2 of the Sequence Listing, but is transcribed using a gene having the same nucleotide sequence as a template. -Even when translated, depending on the type of host into which it is introduced, the components and composition of the nutrient medium used for culture, the temperature and pH during culture, etc., it may be modified by enzymes in the host after gene expression. ,
N in the sequence listing, although retaining the desired enzyme action
One or more amino acids near the terminal may be deleted, or a mutant in which one or more amino acids are newly added to the N-terminal may be produced. Furthermore, recombinant D
Advances in NA technology have made it possible to relatively easily substitute, delete, delete or insert one or more of the constituent amino acids with other amino acids without substantially changing the action of the enzyme. Further, by substituting, deleting, deleting or inserting one or more of the constituent amino acids with another amino acid, properties having high industrial utility value such as improvement in organic solvent resistance and change in substrate specificity Attempts have also been made to create a mutant enzyme with added. In view of such a state of the art, the nitrile hydratase referred to in the present invention is not limited to one having the amino acid sequences shown in SEQ ID NOs: 1 and 2 in the sequence listing as they are, and one or two.
Even if it is a variant having an amino acid sequence in which one or more amino acids are substituted, deleted, deleted or inserted with other amino acids, it is included in the present invention when it has nitrile hydratase activity And

That is, according to the present invention, SEQ ID NO: in the sequence listing:
It is a nitrile hydratase composed of an α subunit represented by the sequence of 205 amino acids shown in 1 and a β subunit represented by the sequence of 233 amino acids shown in SEQ ID NO: 2 in the sequence listing. Further, in the present invention, SEQ ID NO: 1 or 2 in the sequence listing
Part of the amino acid sequence shown in, including, as a constituent, one or both of the α subunit and β subunit obtained by substitution, deletion, deletion or insertion, and,
When it retains nitrile hydration activity, it is included in the nitrile hydratase of the present invention.

In the present invention, SEQ ID NO: 1 in the sequence listing
Α represented by the sequence of 205 amino acids shown in
The nucleotide sequence encoding the subunit is included in the range of the gene encoding the α subunit of nitrile hydratase of the present invention. Further, in the present invention, a part of the amino acid sequence shown in SEQ ID NO: 1 in the sequence listing is replaced,
When the nitrile hydratase containing the α subunit obtained by deletion, deletion or insertion as a component retains the nitrile hydration activity, the nucleotide sequence encoding the α subunit is also the nitrile hydrase of the present invention. Included within the scope of the Tase gene. Similarly, the base sequence encoding the β subunit represented by the sequence of 233 amino acids shown in SEQ ID NO: 2 in the sequence listing is the range of the gene encoding the β subunit of nitrile hydratase of the present invention. include. Further, in the present invention, a nitrile hydratase containing a β subunit as a constituent element obtained by substituting, deleting, deleting or inserting a part of the amino acid sequence represented by SEQ ID NO: 2 in the sequence listing is a nitrile hydrate. When the activity is retained, the nucleotide sequence encoding the β subunit is also included in the scope of the nitrile hydratase gene of the present invention.

The nitrile hydratase gene of the present invention is
It is basically composed of the nucleotide sequences shown in SEQ ID NOs: 3 and 4 of the Sequence Listing, but it can be used as a template for translation relatively easily without substantially changing the amino acid sequence of the enzyme due to the progress of recombinant DNA technology. It has become possible to replace the base sequence of DNA with another base sequence. Furthermore, by substituting, deleting, deleting, or inserting a nucleotide sequence of a DNA serving as a template for translation, one or more of its constituent amino acids can be replaced with other amino acids without substantially changing the action of the enzyme. It has become possible to replace, delete, delete or insert with. In view of the state of the art, the nitrile hydratase gene referred to in the present invention is not limited to one having the DNA base sequences shown in SEQ ID NOs: 3 and 4 in the sequence listing as it is, and one of the DNA base sequences or Mutants in which two or more bases are substituted, deleted, deleted or inserted with other bases are included in the present invention as long as they can function as a template for a protein having nitrile hydratase activity. And That is, the present invention is a gene encoding nitrile hydratase, in which the α subunit is composed of 618 nucleotide sequences shown in SEQ ID NO: 3 in the sequence listing, and the β subunit is SEQ ID NO: in the sequence listing: 4 includes a sequence composed of 702 bases shown in FIG. Further, in the present invention, an α subunit or a sequence listing obtained from an amino acid sequence encoded by a nucleotide sequence obtained by substituting, deleting, deleting or inserting a part of the nucleotide sequence of SEQ ID NO: 3 in the sequence listing Of SEQ ID NO: 4 of SEQ ID NO: 4, a protein containing, as a constituent, either or both of the β subunits obtained by the amino acid sequence encoded by the nucleotide sequence obtained by substitution, deletion, deletion, or insertion Has nitrile hydration activity, it is included in the gene encoding the nitrile hydratase of the present invention.

The present invention comprises constructing a recombinant plasmid into which the gene encoding the nitrile hydratase of the present invention has been inserted, and introducing the recombinant plasmid into any microorganism to obtain a transformant. . Further, the obtained transformant is cultured in a general nutrient medium to produce the enzyme, and the transformant producing the enzyme is contacted with a nitrile compound in an aqueous medium to give a corresponding amide. Including producing a compound.

The recombinant plasmid in the present invention is a plasmid in which a gene encoding nitrile hydratase is inserted into a plasmid vector containing a control region required for expression of the gene and a region required for autonomous replication, and further any It is a plasmid that enables the production of the enzyme when introduced into the host. Examples of the arbitrary host herein include Escherichia coli as in Examples described later, but are not particularly limited to Escherichia coli, and other microorganisms such as Bacillus subtilis Bacillus, yeast, actinomycetes, etc. Can be used. The control region required for expression indicates a promoter sequence (including an operator sequence that controls transcription), a ribosome binding sequence (SD sequence), a transcription termination sequence and the like. Specific promoter sequences include tryptophan operon-derived trp promoter, lactose operon-lac promoter, lambda phage-derived PL promoter and PR promoter, and Bacillus subtilis-derived gluconate synthase promoter (gnt) -alkaline protease promoter. (Apr) / neutral protease promoter (npr) / α-amylase promoter (amy). In addition, uniquely modified / designed sequences such as the tac promoter can also be used. Examples of the ribosome-binding sequence include sequences derived from Escherichia coli or Bacillus subtilis and sequences originally from Pseudonocardia as in the present invention, but are not particularly limited as long as they are sequences that function in a desired host such as Escherichia coli and Bacillus subtilis. It is not something that will be done. For example, a consensus sequence having 4 or more consecutive bases complementary to the 3'terminal region of 16S ribosomal RNA may be prepared by DNA synthesis and used.
A transcription termination sequence is not always required, but is independent of ρ factor, such as lipoprotein terminator tr.
p operon terminator etc. can be used. Regarding the sequence order of these control regions on the recombinant plasmid, it is desirable that the promoter sequence, the ribosome binding sequence, the gene encoding nitrile hydratase, and the transcription termination sequence are arranged in this order from the 5'end upstream. The α subunit gene and the β subunit gene may be expressed as independent cistrons by such a control region, or may be expressed as a polycistron by a common control region.

Examples of the plasmid vector satisfying the above requirements are pBR322, pUC18 and Bluescr which have a region capable of autonomous replication in E. coli.
ipt II SK (+), pKK223-3, pSC1
01, pUB110, pTZ4, pC194, ρ11, φ1, which has a region capable of autonomous replication in Bacillus subtilis.
φ105 and the like can be mentioned. Moreover, pHV14, TRp7, YEp7, and pBS7 can be mentioned as an example of the plasmid vector capable of autonomous replication in two or more types of hosts.

A method for constructing the recombinant plasmid of the present invention by inserting the gene encoding the nitrile hydratase of the present invention into the plasmid vector into a plasmid vector having a region necessary for expression of the gene, The method for transforming into a desired host and the method for producing nitrile hydratase in the transformed cells include:
"Molecular Cloning 2nd Ed
edition ”(T. Maniatis et al .; Cold S
pring Harbor Laboratory P
molecular biology as described in Res., 1989).
General methods and hosts known in the field of biotechnology and genetic engineering may be used. In addition, LB medium, M9 medium and the like are generally used as a medium for culturing the transformant strain, but more preferably, Fe ions and Co ions are present in an amount of 0.1 μg / ml or more in such medium components. .

Further, in order to produce a corresponding amide compound from a nitrile compound using the nitrile hydratase of the present invention or a transformant strain, the desired nitrile compound is added to a culture solution of the transformant strain, or the transformant strain. It may be brought into contact with a transformed bacterial cell obtained by culturing, a treated product of the transformed bacterial cell, or nitrile hydratase isolated and purified from the transformed bacterial cell in an aqueous medium. The contact temperature is not particularly limited, but is preferably within a temperature range in which the nitrile hydratase is not inactivated, and more preferably 0 ° C to 5 ° C.
It is 0 ° C. The nitrile compound is not particularly limited as long as it is a compound to which the nitrile hydratase of the present invention can act as a substrate, but preferably acetonitrile, propionitrile, acrylonitrile, methacrylonitrile, n-butyronitrile, isobutyronitrile, crotono. Typical examples thereof include nitrile compounds having 2 to 4 carbon atoms such as nitrile and α-hydroxyisobutyronitrile. The concentration of the nitrile compound in the aqueous medium is not particularly limited as long as it does not exceed the maximum solubility of the nitrile compound in the aqueous medium,
The amount is preferably 5% by weight or less, more preferably 2% by weight or less, in consideration of inactivation of the enzyme by the nitrile compound.

A series of steps leading to the elucidation of the amino acid sequence and the nucleotide sequence of Pseudonocarcia thermophila-derived nitrile hydratase shown in SEQ ID NOs: 1 to 4 of the sequence listing of the present invention are summarized below. In addition, although it is Pseudonocardia thermophila JCM3095 strain, this strain is a microbial strain preservation facility (2 Hirosawa, Wako City, Saitama Prefecture) of RIKEN.
It is stored under the number JCM3095 in -1) and is freely distributed to anyone by request.

(1) After crushing the cells obtained by culturing the strain, nitrile hydratase is purified by ammonium sulfate fractionation, anion exchange chromatography, gel filtration chromatography, and hydrophobic chromatography to obtain α subunit and The amino acid sequence of the N-terminal 7 residues of the β subunit was determined.

(2) An oligonucleotide primer for gene amplification was prepared based on the determined N-terminal amino acid sequence, and PCR was performed using the chromosomal DNA prepared from the cells as a template to obtain an amplified DNA product.

(3) The chromosomal DNA was partially cleaved with a restriction enzyme to obtain a DNA fragment of about 1500 bp to 4000 bp. This DNA fragment was ligated to a plasmid vector and transformed into Escherichia coli to prepare a plasmid library.

(4) A positive clone containing a DNA fragment encoding nitrile hydratase was selected from the plasmid library by colony hybridization using the amplified DNA product of (2) above as a probe.

(5) Plasmid DN from the positive clone
A was extracted, the entire base sequence of the inserted fragment was determined, and the base sequence of the gene encoding the α subunit / β subunit of nitrile hydratase was specified. The amino acid sequences of the α subunit and β subunit deduced from the nucleotide sequence were compared with the N-terminal amino acid sequences of 7 residues of both subunits obtained in (1) above, and the nucleotide sequence was determined to be nitrile hydratase. I confirmed that the code is

(6) A DNA fragment containing the nitrile hydratase gene was re-prepared from the plasmid of the positive clone of (4) above and inserted into a plasmid vector containing an appropriate promoter.

(7) The plasmid obtained in (6) above was introduced into an appropriate host bacterium to obtain a transformant. Furthermore, it was confirmed that acrylamide was produced by contacting the cells obtained by culturing the transformant with acrylonitrile in an aqueous medium.

[0023]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

Example 1 Purification of Nitrile Hydratase Derived from Pseudonocardia thermophila JCM3095 Strain Pseudonocardia thermophila JCM3095 was prepared from normal broth medium (pH 7.5) containing 0.2% methacrylamide. Was cultured at 50 ° C. for 3 days and centrifuged (8000 × G, 30 minutes) to obtain 3 g of wet cells. This was resuspended in 7 g of KPB (0.1 M potassium phosphate aqueous solution; pH 7.0), and a cell disruption solution was prepared using an ultrasonic disruptor. After 2.7 g of ammonium sulfate was added to the disrupted cell suspension and gently stirred at 4 ° C. for 1 hour, the insoluble matter was removed by centrifugation (25000 × G, 30 minutes). 1.2 g of ammonium sulfate was added to 90 g of the centrifugation supernatant and gently stirred at 4 ° C. for 1 hour, and then a precipitate was obtained by centrifugation (25,000 × G, 30 minutes). Dissolve the precipitate in 1 ml KPB,
This solution was dialyzed for 48 hours at 4 ° C. To-be-dialysed liquid is DEAE-TOYOPEARL650M of Tosoh Corporation.
It was subjected to anion exchange chromatography using (column size 5 × 6 φcm). Using KPB as a developing solution, elution with a concentration gradient from 0 M to 0.5 M with potassium chloride was performed to obtain a fraction containing nitrile hydratase activity.
Next, the active fraction liquid was added to SUPERDE manufactured by Pharmacia.
It was subjected to gel filtration chromatography using X200-26 / 60 as a carrier. As a developing solution, KPB containing 0.2 M potassium chloride was used, and only a fraction containing nitrile hydratase activity was collected. Subsequently, the active fraction liquid was treated with T
SKgel phenyl-5PW column (HPLC
It was subjected to the hydrophobic chromatography used. The sample was adsorbed on a column equilibrated with KPB containing 20% saturated ammonium sulfate, and the ammonium sulfate concentration was adjusted to 2
The active fraction was obtained by a constant gradient reduction from 0% saturation to 0% saturation.

The nitrile hydratase activity in the above chromatography was measured as follows. Each fraction solution was appropriately diluted with KPB, 1% by weight of acrylonitrile was added thereto, and the mixture was reacted at 10 ° C for 10 minutes. To the reaction solution, an equal amount of 1M phosphoric acid aqueous solution was added to stop the reaction, and the concentration of acrylamide produced was adjusted to HPL.
It was measured by C analysis. HPLC column is ULTRON
80 HG (50 × 8 φmm) was used, and a 10 mM phosphoric acid aqueous solution was used as a developing solution. 22 for acrylamide
Detection was by absorbance at 0 nm.

When SDS-PAGE was carried out under reducing conditions using the active fractions obtained by the hydrophobic chromatography, two major polypeptide chains of 29K dalton and 32K dalton and three major chains of 45K dalton or more were detected. The presence of thin polypeptide chains was noted. In SDS-PAGE under the reducing conditions of other nitrile hydratase, generally, two types of polypeptide chains of 30 ± 3 KDa are observed. Therefore, two major polypeptide chains of 29 K dalton and 32 K dalton of SDS-PAGE gel were adsorbed on a PVDF membrane manufactured by Bio-Rad using a semi-dry type blotting apparatus manufactured by Zanatrius. PVDF
Only the portion where the desired polypeptide chain was adsorbed was cut out from the membrane, and the N-terminal amino acid sequence of each was analyzed using a peptide sequencer PSQ-1 manufactured by Shimadzu. As a result, the N of the 29 K dalton polypeptide chain was
The terminal amino acid sequence is Thr-Gl corresponding to the 2nd to 8th amino acid sequences of SEQ ID NO: 1 in the sequence listing.
u-Asn-Ile-Leu-Arg-Lys,
The N-terminal amino acid sequence of the 32 K dalton polypeptide chain corresponds to Met-Asn-Gly-Va corresponding to positions 1 to 7 in the amino acid sequence of SEQ ID NO: 2 in the Sequence Listing.
It was 1-Tyr-Asp-Val.

[Example 2] Acquisition of nitrile hydratase gene derived from Pseudonocardia thermophila JCM3095 strain Pseudonocardia thermophila JCM3095 strain was cultured by the same method as in Example 1 and centrifuged (80
2 × g of wet cells was obtained by (00 × G, 30 minutes). 50 mM EDTA · 2N containing 0.15M NaCl
40 ml of an aqueous solution (pH 8.0) was added to suspend the cells, and the cells were boiled at 90 ° C. for 10 minutes. The treatment liquid is 37 ° C.
After cooling to 100 ° C., 100 mg of egg white lysozyme was added and the mixture was kept at 37 ° C. for 1 hour. Next, 30 mg of 20,000 U / mg zymolase was added and the mixture was kept at 37 ° C. for 1 hour. Subsequently, 5 mg of 20 U / mg proteinase K was added, and the mixture was kept at 37 ° C. for 1 hour. Further, 2 ml of a 10% SDS solution was added, and the mixture was kept at 65 ° C. for 1 hour and then immediately subjected to phenol / chloroform extraction. First, TE
Phenol solution 42 saturated with (10 mM Tris-HCl aqueous solution containing 1 mM EDTA / 2Na; pH 8.0)
ml was added and gently stirred. Centrifuge (3000
The aqueous phase and the organic phase were separated by (rpm, 10 minutes), and only the aqueous phase was separated. 21 ml of the above TE-saturated phenol solution and 21 ml of chloroform were added to this aqueous phase and gently stirred again, followed by centrifugation (3000 rpm, 10 minutes).
The aqueous phase and the organic phase were separated again by, and only the aqueous phase was separated again. After adding 42 ml of chloroform to this aqueous phase and gently stirring again, centrifugation (3000 rpm, 10
The aqueous phase and the organic phase were separated again according to (min.), And only the aqueous phase was separated. TE solution containing 1.1 M NaCl in this aqueous phase 4
ml and ethanol (92 ml) were added and the mixture was allowed to stand at room temperature for a while, and then the precipitated filamentous DNA was wound with a glass rod. Sequential dehydration was performed with 70%, 80%, and 90% ethanol aqueous solutions, and then the air-dried DNA was added to 40 ml of T
Redissolved in solution E. After 30 μg of RNaseA was added and the mixture was incubated at 37 ° C. for 1 hour, it was partially cleaved with the restriction enzyme BamHI. The DNA partially digested by phenol extraction / chloroform extraction and ethanol precipitation was repurified and dissolved in a TE solution to a final concentration of 1.0 μg / μl.

29K Daltons and 3 determined in Example 1
The following four PCR primers were synthesized based on the N-terminal amino acid sequence of the 2K dalton polypeptide chain. Primer 1: 5'-ACNGARAAYATNYTN
MGNAA-3 ′ Primer 2: 5′-TTNCKNARNATRTTTY
TCNGT-3 'Primer 3: 5'-ATGAAYGGNGNTTAY
GANGT-3 ′ primer 4: 5′-ACNTCRTANACNCCR
The primer 1 described in SEQ ID NO: 5 of the TTCAT-3 ′ sequence list and the primer 2 described in SEQ ID NO: 6 of the sequence list correspond to respective complementary strands of the DNA strands corresponding to the N-terminal amino acid sequence of 29 K daltons. The primer 3 described in SEQ ID NO: 7 in the sequence listing and the primer 4 described in SEQ ID NO: 8 in the sequence listing are 32K.
It corresponds to each complementary strand of the DNA strand that corresponds inversely to the N-terminal amino acid sequence of Dalton. In addition, N represents A, C, G or T.

Partially cut chromosomal DNA prepared above
PCR was performed using 3 μg as a template. PCR reaction No.
In No. 1, 200 ng of each of Primers 1 and 4 and Taq
Using a total volume of 100 μl containing 5 U of DNA polymerase, heat denaturation (94 ° C.) for 1 minute, annealing (37 ° C.) 1
40 cycles of PCR under conditions of 1 minute for extension reaction (72 ° C.). PCR reaction No. In Example 2, primers 2 and 3 were each added to 200 ng and Taq DNA polymerase was added to 5
PCR reaction No. 1 was performed in a total volume of 100 μl containing U. The same cycle as 1 was performed. 5 μl of the end solution of each PCR reaction
When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using
CR reaction No. Amplified DNA of about 700bp only in case of 2
The presence of the product was confirmed. From this, it was revealed that in the Pseudonocardia thermophila, the 32K dalton gene and the 29K dalton gene were adjacent to each other in this order from the 5'end upstream.

Agarose gel electrophoresis (using Sigma type VII low melting point agarose; agarose concentration: 0.6% by weight) was performed using the chromosomal DNA solution partially digested with BamHI prepared above, and about agarose gel was used. An agarose piece containing a DNA fragment of 1500 bp to 4000 bp was cut out. The agarose piece (about 0.5
g) was finely crushed and suspended in 5 ml of TE solution, then at 55 ° C.
Agarose was completely thawed by incubating at 37 ° C. for 1 hour, and the resulting melt was subjected to the same phenol / chloroform extraction and ethanol precipitation as described above to purify the DNA fragment. At least 10 pmo of the DNA fragment thus obtained
l Prepare a DNA ligation kit (Takara Shuzo)
Using pUC18 plasmid vector (Takara Shuzo)
Was inserted into the BamHI site within the multi-cloning site. PUC18 used for ligation at this time
The plasmid vector DNA was digested with the restriction enzyme BamHI, purified by phenol / chloroform treatment and ethanol precipitation, and subsequently dephosphorylated at the 5 ′ end using alkaline phosphatase (Takara Shuzo), followed by phenol / chloroform treatment and 20 ng was used after re-purification by ethanol precipitation.

The DNA solution after the ligation reaction was used to transform Escherichia coli HB101 manufactured by Toyobo Co., Ltd. into competent cells (COMPETENT HIGH), and LB agar medium containing 0.5 μg / ml of ampicillin (0.5 μg / ml) was used. % By weight Bacto yeast extract, 1% by weight Bacto tryptone, 0.5% by weight sodium chloride,
About 10 ul of the bacterial solution after the transformation treatment was applied on 1.5 wt% agar; pH 7.5) and cultured at 37 ° C. overnight. As a result, it was possible to obtain a plurality of petri dishes in which 100 to 1000 colonies appeared per sheet.

Amplification DNA by PCR prepared previously for these chromosomal DNA plasmid libraries
Colony hybridization was performed using the product as a probe to screen for clones containing the nitrile hydratase gene of interest.

First, a nylon membrane, Hybond, manufactured by Amersham Co. is placed on a petri dish of the plasmid library.
-N was placed gently and slowly removed after about 1 minute. The stripped membrane is immersed in a denaturing solution (0.5 M NaOH aqueous solution containing 1.5 M NaCl) for 7 minutes, and then the neutralizing solution (1.5 M NaCl and 1 mM EDTA.2N) is added.
0.5M Tris-HCl aqueous solution containing a; pH 7.2) 3
It was treated twice for each minute. Next, 2 x SSC solution (1 x S
SC was washed once with 1 liter of an aqueous solution containing 8.76 g of sodium chloride and 4.41 g of sodium citrate), and then the membrane was air-dried on a dry filter paper. Further, UV irradiation of 120 mJ / cm ² was performed to fix the DNA on the membrane. 30 ml of hybridization buffer (5 × SSC contains the following components per membrane treated in this way: 1
Pre-hybridization was carried out at 42 ° C. for 2 hours by immersing it in 42% by weight skimmed milk, 0.1% by weight N-lauroylsarcosine, 0.02% by weight SDS, 50% by weight formamide. On the other hand, DN amplified by PCR prepared previously
Boehringer Mannheim D using product A as template
A fluorescent labeled probe was prepared using the IG-DNA labeling kit. 100 ng of fluorescent labeled probe and 3
00ng of pUC18 plasmid DNA at 95 ° C for 10
It was heat-denatured by boiling for 1 minute and transferred to 10 ml of hybridization buffer together with the prehybridized membrane. After hybridization at 42 ° C for 24 hours, the membrane was
It was washed twice with 50 ml of 2 × SSC containing 0.1 wt% SDS at room temperature. Then 150 ml of 0.1 wt% SD
Washing was carried out twice at 68 ° C. for 5 minutes in 1 × SSC containing S. Then 100 ml of buffer A (0.3 wt%
Tween 20 and 0.15M NaCl in 0.1
After washing for 5 minutes in M maleic acid buffer; pH 7.5, buffer B (0.3 wt% Tween 20, 0.
Blocking treatment was carried out for 30 minutes at room temperature in 0.1 M maleic acid buffer containing 15 M NaCl and 1 wt% skimimluc; pH 7.5). 30 more
After washing with 0 ml of buffer A at room temperature for 15 minutes twice, 60 ml of buffer C (0.1 M NaC was added).
Equilibration treatment was carried out for 5 minutes with 0.1 M tris hydrochloride aqueous solution containing 1 and 50 mM magnesium chloride; pH 9.5). Luminescent substrate A produced by Boehringer Mannheim
Solution 3 in which MPPD was diluted 100 times with buffer C
The membrane was soaked in 0 ml at room temperature for 10 minutes and then transferred onto a dry filter paper to absorb excess AMPPD. After wrapping the membrane subjected to the above operations in a polyethylene film, the position of the fluorescent signal was confirmed using an X-ray film. As a result, one positive signal was found on the membrane, and a positive colony overlapping the position was confirmed on the original petri dish.

The confirmed positive colonies were inoculated on a petri dish into 10 ml of LB liquid medium containing ampicillin, and cultured overnight at 37 ° C. and 250 rpm.
Plasmid DNA was extracted from the cultured cells by a conventional method, treated with the restriction enzyme BamHI, and then the size of the inserted fragment was confirmed by agarose electrophoresis (agarose concentration: 0.7% by weight). The size was 1 Kbp. This plasmid was named pPT-B1 [FIG. 1 (FIG. 1)], and the entire nucleotide sequence of the inserted fragment was determined by the primer extension method using a sequencing kit manufactured by ABI and auto sequencer 373A. As a result, an open reading frame consisting of nucleotide sequences of 702 bp and 618 bp (each O
RF1 and ORF2) were confirmed in this order from the 5'end side. The most 3'terminal 4 bases of ORF1 including the translation stop codon and the most 5'terminal 4 bases of ORF2 overlapped, which was consistent with the result of PCR. Furthermore, the 7 amino acid sequences on the N-terminal side deduced from the base sequence of ORF1 and the amino acid sequence on the N-terminal side of the 32 K dalton polypeptide chain shown in Example 1 were completely identical. The sequence region corresponds to the first to seventh sequences of the amino acid sequence shown in SEQ ID NO: 2 in the sequence listing.
On the other hand, the 7 amino acid sequences from the 2nd to the 8th N-terminal side of the sequence listing deduced from the base sequence of ORF2 and the 7 amino acid sequences at the N-terminal side of the 29 K dalton polypeptide chain shown in Example 1 The amino acid sequences were also completely identical. The sequence region is 2 of the amino acid sequence of SEQ ID NO: 1 in the sequence listing.
Corresponds to the 8th to 8th arrays. Also, ORF1
The amino acid sequences of and ORF2 showed high homology with the amino acid sequences of the β subunit and α subunit of other nitrile hydratase, respectively. From the above, O
It was confirmed that RF1 is the β-subunit gene of nitrile hydratase and ORF2 is the α-subunit gene.

[Example 3] Construction of transformant strain OR direction and OR of transcription of lac promoter on pPT-B1
The transcription directions of F1 and ORF2 were completely in agreement. Therefore, pPT-B1 is located upstream of the nitrile hydratase gene on pPT-B1 on the 5′-end side and is the only restriction enzyme site on pPT-B1. (Using Sigma type VII low melting point agarose; agarose concentration 0.7%), and about 4.6K from agarose gel
Only the bp DNA fragment was excised. The cut agarose pieces (about 0.1 g) were finely pulverized and suspended in 1 ml of TE solution, and then the mixture was kept at 55 ° C. for 1 hour to completely melt the agarose. Phenol / chloroform extraction and ethanol precipitation to obtain DN
The A fragment was purified. After blunting with a DNA blunting kit (Takara Shuzo), self-ligation was performed with a DNA ligation kit (Takara Shuzo) to construct plasmid pPT-DB1 [Fig. 2 (Fig. 2)]. PPT-DB1 was introduced into HB101 strain using a competent cell of Escherichia coli HB101 manufactured by Toyobo Co., Ltd. to obtain transformant strain MT-10822 strain. As a result, the nitrile hydratase gene was transformed into pUC18 in this strain.
It was transcribed and translated by the upper lac promoter. MT-10822 strain has accession number FERM BP
-5785 has been deposited at the Institute of Biotechnology, Institute of Biotechnology, Institute of Industrial Technology, 1-3-1 Higashi, Tsukuba, Ibaraki.

Example 4 Conversion of Nitrile Compound to Amide Compound by Transformation Strain Example 1 40 μg / m in a 500 ml Erlenmeyer flask with a baffle.
100 ml of LB liquid medium containing 1 L ferric sulfate heptahydrate and 10 μg / ml cobalt chloride dihydrate was prepared and sterilized by autoclaving at 121 ° C. for 20 minutes. Ampicillin was added to this medium to give a final concentration of 100 μg / ml, and then MT obtained in Example 3 was used.
-10822 strain was inoculated with a single bacterium ear, and 37 ° C and 130 rp
The cells were cultured for about 20 hours. Centrifuge (5000G x 1
5 minutes) to separate only the bacterial cells from the culture solution, followed by 5
After resuspending the bacterial cells in 0 ml of physiological saline, centrifugation was carried out again to obtain wet bacterial cells. 100 mg of the wet cells are 2
00 ml of 50 mM potassium phosphate aqueous solution (pH 7.
0), and acrylonitrile was added to the suspension for 10 m.
1 was added and the reaction was carried out at 10 ° C. for 1 hour with gentle stirring. After completion of the reaction, the same HPLC as in Example 1
When the reaction solution was analyzed by analysis, only acrylamide was present in the reaction solution, and neither acrylonitrile nor acrylic acid was found. That is, the conversion rate and the selectivity were 100%.

Example 5 Conversion of Nitrile Compound to Amide Compound by Transforming Strain Example 2 40 μg / m in 500 ml Erlenmeyer flask with baffle.
100 ml of LB liquid medium containing 1 L ferric sulfate heptahydrate and 10 μg / ml cobalt chloride dihydrate was prepared and sterilized by autoclaving at 121 ° C. for 20 minutes. Ampicillin was added to this medium to give a final concentration of 100 μg / ml, and then MT obtained in Example 3 was used.
-10822 strain was inoculated with a simple white bacterium, 37 ° C, 130 rpm
The cells were cultured for about 20 hours. Then, centrifuge (5000G
For 15 minutes), only the bacterial cells were separated from the culture solution. Fifty
After resuspending the bacterial cells in ml of physiological saline, centrifugation was carried out again to obtain wet bacterial cells. 20 mg of the wet bacterial cells
0 ml of 50 mM potassium phosphate aqueous solution (pH 7.
0), and methacrylonitrile was added to the suspension for 5 m.
1 was added and the reaction was carried out at 10 ° C. for 2 hours with gentle stirring. After completion of the reaction, the same HPLC as in Example 1
When the reaction solution was analyzed by analysis, only methacrylamide was present in the reaction solution and neither methacrylonitrile nor methacrylic acid was found. That is,
The conversion and selectivity were 100%.

Example 6 Acquisition of Amino Acid Substitute Having Retention of Nitrile Hydratase Activity (1) The pPT-DB1 plasmid obtained in Example 3 for substituting Met for the 6th Leu of the α subunit. D
"LA PCR in" manufactured by Takara Shuzo Co., Ltd. using NA as a template
Site-directed mutagenesis using "vitro mutagenesis Kit" was performed. After that, "LA PCR
The "in vitro mutagenesis Kit" is simply called a kit. In the following examples, the principle and operating method of the kit were basically followed.

10 ml of LB liquid medium was prepared in a 30 ml test tube and sterilized by autoclaving at 121 ° C. for 20 minutes. Ampicillin was added to this medium so that the final concentration was 100 μg / ml, and the MT-10822 strain obtained in Example 3 was inoculated with a single bacterium ear and incubated at 37 ° C./30.
It was cultured at 0 rpm for about 20 hours. 1 ml of the culture solution was collected in an appropriate centrifuge tube and then centrifuged (15000).
The cells were separated by (rpm × 5 minutes). Then, a plasmid DNA of pPT-DB1 was prepared from the cells by the alkaline SDS extraction method.

1 μg of plasmid DNA of pPT-DB1
Was used as a template to perform two types of PCR reactions. PCR reaction No. 1 is a system (50 μl in total) containing 50 pmol each of the primer described in SEQ ID NO: 9 of the sequence listing and M13 primer M4 (sequence described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit), and heat denaturation (98 ° C) 1
5 seconds, annealing (55 ° C) 30 seconds, extension reaction (72
(° C) 120 seconds was repeated for 25 cycles. PCR reaction No. 2 is a system of 50 μl in total containing 50 pmol each of MUT4 primer (sequence described in SEQ ID NO: 11 of the sequence listing) and M13 primer RV (sequence described in SEQ ID NO: 12 of sequence listing) (composition depends on the conditions described in the kit) ), PCR reaction No. It carried out by the same operation as 1. PCR reaction No. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed.
Using Microcon 100 (Takara Shuzo Co., Ltd.), excess primer and dN from each PCR reaction termination solution
After removing TP, TE was added to each to prepare a 50 μl solution. A total volume of 4 containing 0.5 μl of each TE solution
7.5 μl of an annealing solution (composition is according to the conditions described in the kit) was prepared, subjected to heat denaturation treatment (98 ° C.) for 10 minutes, and then cooled to 37 ° C. at a constant rate for 60 minutes. Annealing treatment was performed by holding at 37 ° C. for 15 minutes. T for the annealing treatment liquid
Add 0.5 μl of AKALALA Taq and mix at 72 ° C for 3
Heat treatment was performed for a minute to complete the heteroduplex. To this, 50 pmol of M13 primer M4 (sequence described in SEQ ID NO: 10 of the sequence listing) and M13 primer RV (sequence described in SEQ ID NO: 12 of sequence listing) were added to give a total amount of 5
After 0 μl, PCR reaction No. was performed by repeating the conditions of heat denaturation (98 ° C.) for 15 seconds, annealing (55 ° C.) for 30 seconds, extension reaction (72 ° C.) for 120 seconds for 25 cycles.
3 was done. PCR reaction No. Analysis of the DNA amplification product by agarose electrophoresis (using Sigma type VII low melting point agarose; agarose concentration 0.8% by weight) using 5 μl of the reaction-completed solution of 3 showed about 2.0 k.
The presence of an amplified DNA product of bp could be confirmed. Subsequently, only a DNA fragment of about 2.0 Kbp was cut out from the agarose gel, the agarose piece (about 0.1 g) was finely crushed, suspended in 1 ml of TE solution, and then incubated at 55 ° C for 1 hour to complete the agarose. Thawed. The melt was subjected to the same phenol / chloroform extraction and ethanol precipitation as in Example 2 to purify the DNA fragment, and finally 10 μm.
It was dissolved in 1 of TE. Purified amplified D of about 2.0 kbp
After the NA fragment was cleaved with restriction enzymes EcoRI and HindIII, the restriction enzyme-treated solution was subjected to the same phenol / chloroform extraction and ethanol precipitation as in Example 2 to purify the DNA fragment, and finally 10 μl of TE was added. Dissolved in. Similarly, EcoRI and HindIII, which are the only restriction enzyme sites on pPT-DB1
-Cut DB1 and perform agarose gel electrophoresis (using Sigma type VII low melting point agarose; agarose concentration 0.7%) to obtain about 2.7 Kbp from the agarose gel.
Only the DNA fragment of was cut out. The cut agarose pieces (about 0.1 g) were finely pulverized, suspended in 1 ml of TE solution, and then kept at 55 ° C. for 1 hour to completely melt the agarose. This melt was subjected to the same phenol / chloroform extraction and ethanol precipitation as in Example 2 to give the DN.
The A fragment was purified and finally dissolved in 10 μl TE.
The amplified DNA product thus obtained and pPT-DB1
After ligating the fragments using a DNA ligation kit (Takara Shuzo), E. coli HB101 competent cells (Toyobo) were transformed to prepare E. coli banks.

In a 30 ml test tube, 40 μg / ml ferric sulfate heptahydrate and 10 μg / ml cobalt chloride
10 ml of LB liquid medium containing dihydrate (hereinafter referred to as activity expression medium) was prepared and sterilized by autoclaving at 121 ° C. for 20 minutes. The final concentration of this medium is 100μ
After adding ampicillin to g / ml, 5 clones arbitrarily selected from the Escherichia coli bank were inoculated with each one white ear and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube and then centrifuged (15000 rpm × 5 minutes).
The bacterial cells were separated by. The cells were suspended in 200 μl of potassium phosphate buffer (pH 7.0), 1% by weight of acrylonitrile was added thereto, and the mixture was reacted at 10 ° C. for 2 minutes. The same amount of 1 M aqueous solution of phosphoric acid as this was added to the reaction solution to stop the reaction, and the concentration of acrylamide produced was measured by the same HPLC analysis as in Example 1. As a result, production of acrylamide was detected in 4 out of 5 clones, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the primer extension method using the same sequencing kit manufactured by ABI and auto sequencer 373A as in Example 2. As a result, in the clones shown in Table 1 [Table 1], the sixth Leu of the α subunit of nitrile hydratase was replaced with Met.

[0043]

[Table 1]

[Example 7] Acquisition of amino acid substitution product retaining nitrile hydratase activity (2) Using pPT-DB1 plasmid DNA as a template to substitute Leu at position 6 of the α subunit with Thr.
Site-specific mutagenesis was performed by the same operation as in Example 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 13 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white ears, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, in the clones shown in Table 2 [Table 2], the sixth Leu of the α subunit of nitrile hydratase was replaced with Thr.

[0048]

[Table 2]

[Example 8] Acquisition of amino acid substitution product retaining nitrile hydratase activity (3) In order to substitute Lea at position 6 of the α subunit with Ala, pPT-DB1 plasmid DNA was used as a template.
Site-specific mutagenesis was performed by the same operation as in Example 6.

Two kinds of PCR reactions were carried out using 1 μg of pPT-DB1 plasmid DNA prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 14 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white ears, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the four clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, in the clones shown in Table 3 [Table 3], the sixth Leu of the α subunit of nitrile hydratase was replaced with Ala.

[0053]

[Table 3]

[Example 9] Acquisition of amino acid substitutions retaining nitrile hydratase activity (4) In order to substitute Leu at position 6 of the α subunit with Val, pPT-DB1 plasmid DNA was used as a template.
Site-specific mutagenesis was performed by the same operation as in Example 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 15 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the active expression medium of Example 6 for each white ears and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, in the clones shown in Table 4 [Table 4], the sixth Leu of the α subunit of nitrile hydratase was replaced with Val.

[0058]

[Table 4]

[Example 10] Acquisition of amino acid substitutions retaining nitrile hydratase activity (5) In order to substitute 19th Ala of the α subunit with Val, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 16 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white ears and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the four clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, in the clones shown in Table 5 [Table 5], the 19th Ala of the α subunit of nitrile hydratase was replaced with Val.

[0063]

[Table 5]

[Example 11] Acquisition of amino acid substitution product retaining nitrile hydratase activity (6) In order to substitute Met at position 38 of the α subunit with Leu, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 17 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the active expression medium of Example 6 for each white ears and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the four clones were separated from the remaining 1 ml of the above culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, in the clones shown in Table 6 [Table 6], Met at position 38 of the α subunit of nitrile hydratase was replaced with Leu.

[0068]

[Table 6]

[Example 12] Acquisition of amino acid substitution product retaining nitrile hydratase activity (7) In order to replace Thr at position 77 of the α subunit with Ser, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 18 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6, one ear of each white bacterium, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the four clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, in the clones shown in Table 7 [Table 7], Thr at the 77th position of the α subunit of nitrile hydratase was replaced with Ser.

[0073]

[Table 7]

[Example 13] Acquisition of amino acid substitutions retaining nitrile hydratase activity (8) In order to substitute Ala for the 90th Gly of the α subunit, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 19 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white bacterium ear and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the four clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, the 90th Gly of the α subunit of nitrile hydratase was replaced with Ala in the clones shown in Table 8 [Table 8].

[0078]

[Table 8]

[Example 14] Acquisition of amino acid substitutions retaining nitrile hydratase activity (9) In order to substitute the 102nd Val of the α subunit with Ala, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 20 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the active expression medium of Example 6 for each white ears, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, in the clones shown in Table 9 [Table 9], the 102nd Val of the α subunit of nitrile hydratase was replaced with Ala.

[0083]

[Table 9]

[Example 15] Acquisition of amino acid substitutions retaining nitrile hydratase activity (10) In order to substitute the 106th Val of the α subunit with Ile, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 21 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white bacterium ear and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 10 [Table 1
[0], the 106th Val of the α subunit of nitrile hydratase was replaced with Ile.

[0088]

[Table 10]

[Example 16] Acquisition of amino acid substitutions retaining nitrile hydratase activity (11) In order to replace Phe at position 126 of the α subunit with Tyr, using pPT-DB1 plasmid DNA as a template Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of pPT-DB1 plasmid DNA prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 22 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white ears and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 11 [Table 1
In the clone shown in [1], Phe at position 126 of the α subunit of nitrile hydratase was replaced with Tyr.

[0093]

[Table 11]

[Example 17] Acquisition of amino acid substitution product retaining nitrile hydratase activity (12) In order to replace Gln at position 130 of the α subunit with Glu, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 23 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the active expression medium of Example 6 for each white ears, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 12 [Table 1
In the clone shown in [2], Gln at the 130th position of the α subunit of nitrile hydratase was replaced with Glu.

[0098]

[Table 12]

[Example 18] Acquisition of amino acid substitutions retaining nitrile hydratase activity (13) In order to substitute Leu at position 142 of the α subunit with Val, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 24 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the active expression medium of Example 6 for each white ears, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 13 [Table 1
In the clone shown in [3], the 142nd Leu of the α subunit of nitrile hydratase was replaced with Val.

[0103]

[Table 13]

[Example 19] Acquisition of amino acid substitutions retaining nitrile hydratase activity (14) In order to replace Glu at position 146 of the α subunit with Asp, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 25 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the active expression medium of Example 6 for each white ears, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the above culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 14 [Table 1
In the clone shown in [4], Glu at position 146 of the α subunit of nitrile hydratase was replaced with Asp.

[0108]

[Table 14]

[Example 20] Acquisition of amino acid substitutions retaining nitrile hydratase activity (15) In order to substitute Ala at the 187th position of the α subunit with Thr, using pPT-DB1 plasmid DNA as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the pPT-DB1 plasmid DNA prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 26 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white ears and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the four clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 15 [Table 1
In the clone shown in 5], Ala at position 187 of the α subunit of nitrile hydratase was replaced with Thr.

[0113]

[Table 15]

[Example 21] Acquisition of amino acid substitutions retaining nitrile hydratase activity (16) In order to substitute Ser at position 194 of the α subunit with Leu, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 27 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white bacterium ear and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 16 [Table 1
In the clone shown in [6], Ser at position 194 of the α subunit of nitrile hydratase was replaced with Leu.

[0118]

[Table 16]

[Example 22] Acquisition of amino acid substitutions retaining nitrile hydratase activity (17) In order to substitute Alu at position 203 of the α subunit with Glu, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of pPT-DB1 plasmid DNA prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 28 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the active expression medium of Example 6 for each white bacterium ear and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 17 [Table 1
In the clone shown in [7], Ala at the 203rd position of the α subunit of nitrile hydratase was replaced with Glu.

[0123]

[Table 17]

[Example 23] Obtainment of amino acid substitution product retaining nitrile hydratase activity (18) [0124] In order to substitute 20th Ala of β subunit with Val, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 29 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the active expression medium of Example 6 for each white bacterium ear and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 18 [Table 1
In the clone shown in [8], the 20th Ala of the β subunit of nitrile hydratase was converted to Val.

[0128]

[Table 18]

[Example 24] Acquisition of amino acid substitutions retaining nitrile hydratase activity (19) [0129] In order to substitute Asn for Asp at position 21 of the β subunit, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 30 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white ears, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 19 [Table 1
In the clone shown in [9], the 21st Asp of the β subunit of nitrile hydratase was replaced with Asn.

[0133]

[Table 19]

[Example 25] Acquisition of amino acid substitutions retaining nitrile hydratase activity (20) In order to replace Glu at position 108 of the β subunit with Asp, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 31 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white ears and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the four clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 20 [Table 2
In the clone shown in [0], Glu at position 108 of the β subunit of nitrile hydratase was replaced with Asp.

[0138]

[Table 20]

[Example 26] Acquisition of amino acid substitutions retaining nitrile hydratase activity (21) In order to substitute Glu at position 108 of β subunit with Pro, using pPT-DB1 plasmid DNA as a template Site-specific mutagenesis was performed by the same operation as in 6.

Two types of PCR reactions were carried out using 1 μg of the pPT-DB1 plasmid DNA prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 32 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity-expressing medium of Example 6, one ear of each white bacterium, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 21 [Table 2
In the clone shown in 1], Glu at the 108th position of the β subunit of nitrile hydratase was replaced with Pro.

[0143]

[Table 21]

[Example 27] Acquisition of amino acid substitutions retaining nitrile hydratase activity (22) In order to substitute Glu at position 108 of β subunit with Ser, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of pPT-DB1 plasmid DNA prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 33 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the active expression medium of Example 6 for each white bacterium ear and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 22 [Table 2
In the clone shown in [2], Glu at the 108th position of the β subunit of nitrile hydratase was replaced with Ser.

[0148]

[Table 22]

[Example 28] Acquisition of amino acid substitution product retaining nitrile hydratase activity (23) In order to replace Glu at position 108 of β subunit with Arg, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 34 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white bacterium ear, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 23 [Table 2
In the clone shown in [3], the 108th Glu of the β subunit of nitrile hydratase was replaced with Arg.

[0153]

[Table 23]

[Example 29] Acquisition of amino acid substitution product retaining nitrile hydratase activity (24) [0154] In order to replace Glu at position 108 of the β subunit with Cys, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of pPT-DB1 plasmid DNA prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 35 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity-expressing medium of Example 6 for each white ears, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 24 [Table 2
In the clone shown in 4], Glu at the 108th position of the β subunit of nitrile hydratase was replaced with Cys.

[0158]

[Table 24]

[Example 30] Acquisition of amino acid substitution product retaining nitrile hydratase activity (25) In order to replace Glu at position 108 of the β subunit with Leu, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 36 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the active expression medium of Example 6 for each white ears and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 25 [Table 2
In the clone shown in [5], Glu at the 108th position of the β subunit of nitrile hydratase was replaced with Leu.

[0163]

[Table 25]

[Example 31] Obtainment of amino acid substitutions retaining nitrile hydratase activity (26) [0164] In order to substitute Glu at position 108 of the β subunit with Thr, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the pPT-DB1 plasmid DNA prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 37 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white bacterium ear and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the four clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 26 [Table 2
In the clone shown in [6], Glu at position 108 of the β subunit of nitrile hydratase was replaced with Thr.

[0168]

[Table 26]

[Example 32] Acquisition of amino acid substitutions retaining nitrile hydratase activity (27) In order to substitute Asp at position 200 of the β subunit with Asp, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 38 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity-expressing medium of Example 6 for each white ears, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the four clones were separated from the remaining 1 ml of the above culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 27 [Table 2
In the clone shown in [7], the 200th Ala of the β subunit of nitrile hydratase was replaced with Asp.

[0173]

[Table 27]

[Example 33] Acquisition of amino acid substitution product retaining nitrile hydratase activity (28) [0174] In order to substitute Ale at position 200 of β subunit with Ile, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 39 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white bacterium ear and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 28 [Table 2
In the clone shown in [8], the 200th Ala of the β subunit of nitrile hydratase was replaced with Ile.

[0178]

[Table 28]

Example 34 Acquisition of Amino Acid Substitute Having Retention of Nitrile Hydratase Activity (29) In order to replace 200th Ala of β subunit with Val, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 40 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white ears, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 29 [Table 2
In the clone shown in [9], the 200th Ala of the β subunit of nitrile hydratase was replaced with Val.

[0183]

[Table 29]

Example 35 Acquisition of Amino Acid Substitute Having Retention of Nitrile Hydratase Activity (30) In order to replace Ala at position 200 of β subunit with Glu, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the plasmid DNA of pPT-DB1 prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 41 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6, one ear of each white bacterium, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 30 [Table 3
0], the 200th Ala of the β subunit of nitrile hydratase was replaced with Glu.

[0188]

[Table 30]

[Example 36] Acquisition of amino acid substitutions retaining nitrile hydratase activity (31) [0189] In order to substitute Ser at position 212 of the β subunit with Tyr, pPT-DB1 plasmid DNA was used as a template. Site-specific mutagenesis was performed by the same operation as in 6.

Two kinds of PCR reactions were carried out using 1 μg of the pPT-DB1 plasmid DNA prepared in Example 6 as a template. PCR reaction No. 1 is SEQ ID NO: 42 in the sequence listing
A total volume of 50 μl containing 50 pmol each of the described primer and M13 primer M4 (sequence is described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit)
Heat denaturation (98 ° C) for 15 seconds, annealing (55 ° C)
It was carried out by repeating the condition of 30 seconds and extension reaction (72 ° C.) 120 seconds for 25 cycles. PCR reaction No. Two
Is a total amount of 50 μm including 50 pmol of MUT4 primer (sequence is shown in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of sequence listing).
1 system (the composition depends on the conditions described in the kit), PCR
Reaction No. It carried out by the same operation as 1. PCR reaction N
o. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6, one ear of each white bacterium, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the four clones were separated from the remaining 1 ml of the above culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 31 [Table 3
In the clone shown in [1], Ser at position 212 of the β subunit of nitrile hydratase was replaced with Tyr.

[0193]

[Table 31]

[Example 37] Acquisition of amino acid substitution product retaining nitrile hydratase activity (32) Clone No. Amino acid mutation (19th α subunit: Ala is Val) of 5 strains and clone No. It was confirmed that the nitrile hydratase activity was retained even in the amino acid substitution product having both the 11 amino acid mutations (126 of the α subunit: Phe is Tyr).

10 ml of LB liquid medium was prepared in a 30 ml test tube and sterilized by autoclaving at 121 ° C. for 20 minutes. Ampicillin was added to this medium to a final concentration of 100 μg / ml, and then clone No. 1 obtained in Example 16 was used. Eleven strains were inoculated with monospores at 37 ° C.
The culture was performed at 300 rpm for about 20 hours. 1 ml of the culture solution
Into a suitable centrifuge tube and then centrifuge (150
The cells were separated by (00 rpm × 5 minutes). Subsequently, the clone No. was extracted from the cells by the alkaline SDS extraction method. 11
The strain's plasmid DNA was prepared.

Clone No. 11 strains of plasmid DNA
Two kinds of PCR reactions were performed using 1 μg as a template. PC
R reaction No. 1 is the primer described in SEQ ID NO: 16 in the sequence listing and M13 primer M4 (SEQ ID NO: 10 in the sequence listing).
In a total amount of 50 μl each containing 50 pmol of each sequence (the composition depends on the conditions described in the kit), and heat denaturation (9
It was carried out by repeating 15 cycles of 15 seconds at 8 ° C., 30 seconds at annealing (55 ° C.) and 120 seconds at extension reaction (72 ° C.) for 25 cycles. PCR reaction No. 2 is MUT4 primer (sequence is shown in SEQ ID NO: 11 of Sequence Listing) and M1
PCR reaction No. 3 was carried out in a total volume of 50 μl containing 50 pmol of each of 3 primer RVs (sequences are shown in SEQ ID NO: 12 of the sequence listing) (composition depends on the conditions described in the kit). It carried out by the same operation as 1. PCR reaction No. 1 and N
o. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white bacterium ear and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 32 [Table 3
As shown in [2], α of wild-type nitrile hydratase
The 19th Ala of the subunit was replaced with Val and the 126th Phe of the α subunit was replaced with Tyr.

[0199]

[Table 32]

[Example 38] Acquisition of amino acid substitution product retaining nitrile hydratase activity (33) Clone No. Amino acid mutation of strain 1 (6th α subunit: Leu is Met) and clone No. Amino acid mutation in 32 strains (19th Ala of α subunit is Va
1; It was confirmed that the nitrile hydratase activity is retained even in an amino acid substitution product in which Phe at position 126 of the α subunit has Tyr).

10 ml of LB liquid medium was prepared in a 30 ml test tube and sterilized by autoclaving at 121 ° C. for 20 minutes. Ampicillin was added to this medium to a final concentration of 100 μg / ml, and then clone No. 1 obtained in Example 37 was used. 32 strains were inoculated with monospores of ear strains at 37 ℃
The culture was performed at 300 rpm for about 20 hours. 1 ml of the culture solution
Into a suitable centrifuge tube and then centrifuge (150
The cells were separated by (00 rpm × 5 minutes). Subsequently, the clone No. was extracted from the cells by the alkaline SDS extraction method. 32
The strain's plasmid DNA was prepared.

Clone No. 32 strains of plasmid DNA
Two kinds of PCR reactions were performed using 1 μg as a template. PC
R reaction No. 1 is a system (50 μl in total) containing 50 pmol each of the primer described in SEQ ID NO: 9 of the sequence listing and M13 primer M4 (sequence described in SEQ ID NO: 10 of the sequence listing) (composition depends on the conditions described in the kit) (98
C.) for 15 seconds, annealing (55.degree. C.) for 30 seconds, and extension reaction (72.degree. C.) for 120 seconds. PCR reaction No. 2 is MUT4 primer (sequence is shown in SEQ ID NO: 11 of Sequence Listing) and M13
Primer RV (sequence described in SEQ ID NO: 12 in the sequence listing)
In a total amount of 50 μl containing 50 pmol of each (the composition depends on the conditions described in the kit), and the PCR reaction No. It carried out by the same operation as 1. PCR reaction No. 1 and No.
When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white bacterium ear and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the four clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 33 [Table 3
[3], α of wild-type nitrile hydratase
The 6th Leu of the subunit was replaced with Met, the 19th Ala of the α subunit was replaced with Val, and the 126th Phe of the α subunit was replaced with Tyr.

[0205]

[Table 33]

[Example 39] Acquisition of amino acid substitution product retaining nitrile hydratase activity (34) Clone No. Amino acid mutations in the 2 strains (6th α subunit: Leu is Thr) and clone No. Amino acid mutation in 32 strains (19th Ala of α subunit is Va
1; It was confirmed that the nitrile hydratase activity is retained even in an amino acid substitution product in which Phe at position 126 of the α subunit has Tyr).

Clone No. prepared in Example 38. 32
Two types of PC using 1 μg of plasmid DNA of the strain as a template
The R reaction was performed. PCR reaction No. 1 is the primer described in SEQ ID NO: 13 of the sequence listing and M13 primer M4
50 pm each (listed in SEQ ID NO: 10 in the sequence listing)
25 cycles of heat denaturation (98 ° C.) for 15 seconds, annealing (55 ° C.) for 30 seconds, and extension reaction (72 ° C.) for 120 seconds in a total volume of 50 μl (including composition) according to the conditions described in the kit. Went by. PCR reaction No. 2 is a MUT4 primer (SEQ ID NO: 1 in the sequence listing)
1) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of the sequence listing) in a total volume of 50 μl (the composition depends on the conditions described in the kit).
PCR reaction No. It carried out by the same operation as 1. P
CR reaction No. 1 and No. 5 μl for each reaction completion solution
The presence of the amplified DNA product was confirmed by analyzing the DNA amplification product by agarose gel electrophoresis (agarose concentration 1.0% by weight). Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the active expression medium of Example 6 for each white bacterium ear, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 34 [Table 3
[4], the wild type nitrile hydratase α
The 6th Leu of the subunit was replaced with Thr, the 19th Ala of the α subunit was replaced with Val, and the 126th Phe of the α subunit was replaced with Tyr.

[0210]

[Table 34]

[Example 40] Acquisition of amino acid substitution product retaining nitrile hydratase activity (35) Clone No. Amino acid mutations in the 3 strains (6th α subunit: Leu is Ala) and clone No. Amino acid mutation in 32 strains (19th Ala of α subunit is Va
1; It was confirmed that the nitrile hydratase activity is retained even in an amino acid substitution product in which Phe at position 126 of the α subunit has Tyr).

Clone No. prepared in Example 38. 32
Two types of PC using 1 μg of plasmid DNA of the strain as a template
The R reaction was performed. PCR reaction No. 1 is the primer of SEQ ID NO: 14 in the sequence listing and M13 primer M4
50 pm each (listed in SEQ ID NO: 10 in the sequence listing)
25 cycles of heat denaturation (98 ° C.) for 15 seconds, annealing (55 ° C.) for 30 seconds, and extension reaction (72 ° C.) for 120 seconds in a total volume of 50 μl (including composition) according to the conditions described in the kit. Went by. PCR reaction No. 2 is a MUT4 primer (SEQ ID NO: 1 in the sequence listing)
1) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of the sequence listing) in a total volume of 50 μl (the composition depends on the conditions described in the kit).
PCR reaction No. It carried out by the same operation as 1. P
CR reaction No. 1 and No. 5 μl for each reaction completion solution
The presence of the amplified DNA product was confirmed by analyzing the DNA amplification product by agarose gel electrophoresis (agarose concentration 1.0% by weight). Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white ears, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 35 [Table 3
[5], α of wild-type nitrile hydratase
The 6th Leu of the subunit was replaced with Ala, the 19th Ala of the α subunit was replaced with Val, and the 126th Phe of the α subunit was replaced with Tyr.

[0215]

[Table 35]

[Example 41] Acquisition of amino acid substitution product retaining nitrile hydratase activity (36) Clone No. Amino acid mutations of strain 20 (β subunit 108: Glu is Asp) and clone No. 20. 31
Amino acid mutation in the strain (212nd β subunit: Se
It was confirmed that the nitrile hydratase activity is retained even in the amino acid substitution product in which r has both Tyr).

10 ml of LB liquid medium was prepared in a 30 ml test tube and sterilized by autoclaving at 121 ° C. for 20 minutes. Ampicillin was added to this medium so that the final concentration was 100 μg / ml, and then clone No. 1 obtained in Example 36 was used. 31 strains were inoculated with monospores at 37 ° C.
The culture was performed at 300 rpm for about 20 hours. 1 ml of the culture solution
Into a suitable centrifuge tube and then centrifuge (150
The cells were separated by (00 rpm × 5 minutes). Subsequently, the clone No. was extracted from the cells by the alkaline SDS extraction method. 31
The strain's plasmid DNA was prepared.

Clone No. 31 strains of plasmid DNA
Two kinds of PCR reactions were performed using 1 μg as a template. PC
R reaction No. 1 is the primer described in SEQ ID NO: 31 in the sequence listing and M13 primer M4 (SEQ ID NO: 10 in the sequence listing).
In a total amount of 50 μl each containing 50 pmol of each sequence (the composition depends on the conditions described in the kit), and heat denaturation (9
It was carried out by repeating 15 cycles of 15 seconds at 8 ° C., 30 seconds at annealing (55 ° C.) and 120 seconds at extension reaction (72 ° C.) for 25 cycles. PCR reaction No. 2 is MUT4 primer (sequence is shown in SEQ ID NO: 11 of Sequence Listing) and M1
PCR reaction No. 3 was carried out in a total volume of 50 μl containing 50 pmol of each of 3 primer RVs (sequences are shown in SEQ ID NO: 12 of the sequence listing) (composition depends on the conditions described in the kit). It carried out by the same operation as 1. PCR reaction No. 1 and N
o. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white bacterium ear and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 36 [Table 3
[6], β of wild-type nitrile hydratase
Glu at the 108th subunit was replaced with Asp, and Ser at the 212th β subunit was replaced with Tyr.

[0221]

[Table 36]

[Example 42] Acquisition of amino acid substitution product retaining nitrile hydratase activity (37) Clone No. Amino acid mutation of the 23 strain (108 of β subunit: Glu is Arg) and clone No. 31
Amino acid mutation in the strain (212nd β subunit: Se
It was confirmed that the nitrile hydratase activity is retained even in the amino acid substitution product in which r has both Tyr).

Clone No. prepared in Example 41. 31
Two types of PC using 1 μg of plasmid DNA of the strain as a template
The R reaction was performed. PCR reaction No. 1 is the primer described in SEQ ID NO: 34 of the sequence listing and M13 primer M4
50 pm each (listed in SEQ ID NO: 10 in the sequence listing)
25 cycles of heat denaturation (98 ° C.) for 15 seconds, annealing (55 ° C.) for 30 seconds, and extension reaction (72 ° C.) for 120 seconds in a total volume of 50 μl (including composition) according to the conditions described in the kit. Went by. PCR reaction No. 2 is a MUT4 primer (SEQ ID NO: 1 in the sequence listing)
1) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of the sequence listing) in a total volume of 50 μl (the composition depends on the conditions described in the kit).
PCR reaction No. It carried out by the same operation as 1. P
CR reaction No. 1 and No. 5 μl for each reaction completion solution
The presence of the amplified DNA product was confirmed by analyzing the DNA amplification product by agarose gel electrophoresis (agarose concentration 1.0% by weight). Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6, one ear of each white bacterium, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 37 [Table 3
[7], β of wild-type nitrile hydratase
The 108th Glu of the subunit was replaced with Arg, and the 212th Ser of the β subunit was replaced with Tyr.

[0226]

[Table 37]

[Example 43] Acquisition of amino acid substitution product retaining nitrile hydratase activity (38) Clone No. Amino acid mutation of the 27th strain (200th β subunit: Ala is Asp) and clone No. 31
Amino acid mutation in the strain (212nd β subunit: Se
It was confirmed that the nitrile hydratase activity is retained even in the amino acid substitution product in which r has both Tyr).

Clone No. prepared in Example 41. 31
Two types of PC using 1 μg of plasmid DNA of the strain as a template
The R reaction was performed. PCR reaction No. 1 is the primer described in SEQ ID NO: 38 of the sequence listing and M13 primer M4
50 pm each (listed in SEQ ID NO: 10 in the sequence listing)
25 cycles of heat denaturation (98 ° C.) for 15 seconds, annealing (55 ° C.) for 30 seconds, and extension reaction (72 ° C.) for 120 seconds in a total volume of 50 μl (including composition) according to the conditions described in the kit. Went by. PCR reaction No. 2 is a MUT4 primer (SEQ ID NO: 1 in the sequence listing)
1) and M13 primer RV (sequence is shown in SEQ ID NO: 12 of the sequence listing) in a total volume of 50 μl (the composition depends on the conditions described in the kit).
PCR reaction No. It carried out by the same operation as 1. P
CR reaction No. 1 and No. 5 μl for each reaction completion solution
The presence of the amplified DNA product was confirmed by analyzing the DNA amplification product by agarose gel electrophoresis (agarose concentration 1.0% by weight). Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white bacterium ear and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 38 [Table 3
[8], β of wild-type nitrile hydratase
The 200th Ala of the subunit was replaced with Asp, and the 212th Ser of the β subunit was replaced with Tyr.

[0231]

[Table 38]

[Example 44] Acquisition of amino acid substitution product retaining nitrile hydratase activity (39) Clone No. Amino acid mutation of the 30 strain (200th β subunit: Ala is Glu) and clone No. 31
Amino acid mutation in the strain (212nd β subunit: Se
It was confirmed that the nitrile hydratase activity is retained even in the amino acid substitution product in which r has both Tyr).

Clone No. prepared in Example 41. 31
Two types of PC using 1 μg of plasmid DNA of the strain as a template
The R reaction was performed. PCR reaction No. 1 is 50 pmol each of the primer described in SEQ ID NO: 41 of the sequence listing and the M13 primer M4 (sequence described in SEQ ID NO: 10 of the sequence listing)
In a total volume of 50 μl (including composition according to the conditions described in the kit), heat denaturation (98 ° C.) for 15 seconds, annealing (55
℃) 30 seconds, extension reaction (72 ℃) 120 seconds conditions of 25
This was done by repeating the cycle. PCR reaction No.
2 is a total amount of 50 pmol each containing 50 pmol of MUT4 primer (sequence is listed in SEQ ID NO: 11 of sequence listing) and M13 primer RV (sequence is listed in SEQ ID NO: 12 of sequence listing)
μl system (composition depends on the conditions stated in the kit), PC
R reaction No. It carried out by the same operation as 1. PCR reaction No. 1 and No. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl of each reaction-terminating solution of 2, the amplified DNA was obtained.
The presence of the product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6, one ear of each white bacterium, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the 4 clones were separated from the remaining 1 ml of the above culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 39 [Table 3
[9], β of wild-type nitrile hydratase
The 200th Ala of the subunit was replaced with Glu, and the 212th Ser of the β subunit was replaced with Tyr.

[0236]

[Table 39]

[Example 45] Acquisition of amino acid substitution product retaining nitrile hydratase activity (40) Clone No. Amino acid mutation of the 23 strain (108 of β subunit: Glu is Arg) and clone No. 39
Amino acid mutation of the strain (200th Al of β subunit
a is Glu; 212th Ser of β subunit is T
It was confirmed that the nitrile hydratase activity was retained even in the amino acid substitution product having both yr).

10 ml of LB liquid medium was prepared in a 30 ml test tube and sterilized by autoclaving at 121 ° C. for 20 minutes. Ampicillin was added to this medium to a final concentration of 100 μg / ml, and then clone No. 1 obtained in Example 44 was used. 39 strains were inoculated with monospores at 37 ° C.
The culture was performed at 300 rpm for about 20 hours. 1 ml of the culture solution
Into a suitable centrifuge tube and then centrifuge (150
The cells were separated by (00 rpm × 5 minutes). Subsequently, the clone No. was extracted from the cells by the alkaline SDS extraction method. 39
The strain's plasmid DNA was prepared.

Clone No. 39 strains of plasmid DNA
Two kinds of PCR reactions were performed using 1 μg as a template. PC
R reaction No. 1 is the primer described in SEQ ID NO: 34 in the sequence listing and M13 primer M4 (SEQ ID NO: 10 in the sequence listing).
In a total amount of 50 μl each containing 50 pmol of each sequence (the composition depends on the conditions described in the kit), and heat denaturation (9
It was carried out by repeating 15 cycles of 15 seconds at 8 ° C., 30 seconds at annealing (55 ° C.) and 120 seconds at extension reaction (72 ° C.) for 25 cycles. PCR reaction No. 2 is MUT4 primer (sequence is shown in SEQ ID NO: 11 of Sequence Listing) and M1
PCR reaction No. 3 was carried out in a total volume of 50 μl containing 50 pmol of each of 3 primer RVs (sequences are shown in SEQ ID NO: 12 of the sequence listing) (composition depends on the conditions described in the kit). It carried out by the same operation as 1. PCR reaction No. 1 and N
o. When the DNA amplification product was analyzed by agarose electrophoresis (agarose concentration 1.0% by weight) using 5 μl each of the reaction-completed solution of 2, the presence of the amplified DNA product was confirmed. Thereafter, an E. coli bank was prepared by the same procedure as in Example 6.

Five clones arbitrarily selected from the Escherichia coli bank were inoculated into 10 ml of the activity expression medium of Example 6 for each white ears, and cultured at 37 ° C. and 300 rpm for about 20 hours. 1 ml of the culture-finished solution was collected in an appropriate centrifuge tube, and the nitrile hydratase activity was measured by the same procedure as in Example 6. As a result, 4 out of 5 clones
Generation of acrylamide was detected in the clone, and it was confirmed that the nitrile hydratase activity was retained.

The cells of the four clones were separated from the remaining 1 ml of the culture solution used for the measurement of nitrile hydratase activity, and the plasmid DNA of each clone was prepared by the alkaline SDS extraction method. Then, the nucleotide sequence of the nitrile hydratase structural gene of each clone was determined by the same operation as in Example 2. As a result, Table 40 [Table 4
0], β of wild-type nitrile hydratase
The 108th Glu of the subunit was replaced with Arg, the 200th Ala of the β subunit was replaced with Glu, and the 212nd Ser of the β subunit was replaced with Tyr.

[0242]

[Table 40]

[Example 46] Acquisition of amino acid substitution product retaining nitrile hydratase activity (41) Clone No. Amino acid mutation of strain 34 and clone No.
It was confirmed that the nitrile hydratase activity was retained even in the amino acid substitutions having 36 amino acid mutations.

10 ml of LB liquid medium was prepared in a 30 ml test tube and sterilized by autoclaving at 121 ° C. for 20 minutes. Ampicillin was added to this medium to a final concentration of 100 μg / ml, and then clone No. 1 obtained in Example 39 was used. 34 strain and the clone No. obtained in Example 41. Thirty-six strains were inoculated with monospores of ear strains at 37 ℃
It was cultured at 0 rpm for about 20 hours. 1 ml of the culture solution was collected in an appropriate centrifuge tube and then centrifuged (15000).
Each bacterial cell was separated by (rpm × 5 minutes). Subsequently, clone N was extracted from the cells by alkaline SDS extraction method.
o. 34 strain and clone no. 36 strains of plasmid DN
A was prepared respectively.

Clone No. 36 strains of plasmid DNA
The only restriction enzyme sites above are EcoRI and No
After cleaving the plasmid DNA with tI, agarose gel electrophoresis (using Sigma type VII low melting point agarose; agarose concentration 1.0%) was performed to cut out a DNA fragment of about 770 bp from the agarose gel. Similarly, clone no. After cleaving the plasmid DNA with EcoRI and NotI, which are the only restriction enzyme sites on the plasmid DNA of 34 strains, agarose gel electrophoresis (using Sigma type VII low melting point agarose; agarose concentration 0.7%) was performed. A DNA fragment of about 3.8 kbp was cut out from an agarose gel. Cut both agarose pieces (about 0.1g) into 1m
After being suspended in each 1 l of TE solution, the agarose was completely melted by incubating at 55 ° C. for 1 hour. The melt was subjected to the same phenol / chloroform extraction and ethanol precipitation as in Example 2 to purify each DNA fragment, and finally 1
It was dissolved in 0 μl TE.

[0246] The clone No. 36
About 770 bp DNA fragment derived from the strain and clone No. Three
About 3.8 Kbp DNA fragments derived from 4 strains were ligated using a DNA ligation kit (Takara Shuzo) to obtain pP.
T-DB41 was constructed. This pPT-DB41 plasmid DNA was introduced into a competent cell of Escherichia coli HB101 (manufactured by Toyobo Co., Ltd.), and E. coli clone No. 41 strains were obtained.

Clone No. Forty-one strains were inoculated into 10 ml of the activity expression medium of Example 6, one ear of each white bacterium, at 37 ° C.
It was cultured at 0 rpm for about 20 hours. 1 ml of the culture completion liquid
Example 6 after separating each of them into an appropriate centrifuge tube
The nitrile hydratase activity was measured by the same procedure as in. As a result, the production of acrylamide was detected, and clone No. It was confirmed that 41 strains retain nitrile hydratase activity.

The cells were separated from the remaining 1 ml of the above culture solution used for the measurement of nitrile hydratase activity, and alkali S
The plasmid DNA of each clone was prepared by the DS extraction method. Then, by the same operation as in Example 2, clone N
o. The nucleotide sequence of the nitrile hydratase structural gene of strain 41 was determined. As a result, as shown in Table 41 [Table 41], Leu at position 6 of the α subunit of wild-type nitrile hydratase was in Thr, Ala at position 19 of the α subunit was in Val, and 126 of α subunit was 126. Th P
he is Tyr and the 108th Glu of β subunit
Is the Asp and the 212th Ser of the β subunit is T
were each replaced by yr.

[0249]

[Table 41]

[Example 47] Acquisition of amino acid substitution product retaining nitrile hydratase activity (42) Clone No. Amino acid mutation of strain 34 and clone No.
It was confirmed that the nitrile hydratase activity was retained even in the amino acid substitutions having the 37 amino acid mutations.

10 ml of LB liquid medium was prepared in a 30 ml test tube and sterilized by autoclaving at 121 ° C. for 20 minutes. Ampicillin was added to this medium to a final concentration of 100 μg / ml, and then clone No. 1 obtained in Example 42 was used. 37 strains were inoculated with 1 Saccharomyces cerevisiae at 37 ℃
The culture was performed at 300 rpm for about 20 hours. 1 ml of the culture solution
Into a suitable centrifuge tube and then centrifuge (150
The cells were separated by (00 rpm × 5 minutes). Subsequently, the clone No. was extracted from the cells by the alkaline SDS extraction method. 37
The strain's plasmid DNA was prepared.

Clone No. Plasmid DNA of 37 strains
The only restriction enzyme sites above are EcoRI and No
After cleaving the plasmid DNA with tI, agarose gel electrophoresis (using Sigma type VII low melting point agarose; agarose concentration 1.0%) was performed to cut out a DNA fragment of about 770 bp from the agarose gel. Similarly, the clone No. prepared in Example 46 was used. Eco which is the only restriction enzyme site on plasmid DNA of 34 strains
After cleaving the plasmid DNA with RI and NotI, agarose gel electrophoresis (Type VII manufactured by Sigma)
Low melting point agarose was used; agarose concentration was 0.7%), and a DNA fragment of about 3.8 kbp was cut out from the agarose gel. Both pieces of agarose cut out (about 0.1g)
Finely crushed and suspended in 1 ml of TE solution, then 5
The agarose was completely melted by incubating at 5 ° C for 1 hour.
The melt was subjected to the same phenol / chloroform extraction and ethanol precipitation as in Example 2 to purify each DNA fragment, and finally dissolved in 10 μl of TE.

The clone No. thus obtained was 37
About 770 bp DNA fragment derived from the strain and clone No. Three
About 3.8 Kbp DNA fragments derived from 4 strains were ligated using a DNA ligation kit (Takara Shuzo) to obtain pP.
T-DB42 was constructed. This pPT-DB42 plasmid DNA was introduced into a competent cell of Escherichia coli HB101 (manufactured by Toyobo Co., Ltd.), and E. coli clone No. 42 strains were obtained.

Clone No. Forty-two strains were inoculated into 10 ml of the activity expression medium of Example 6, one ear of each white bacterium, at 37 ° C.
It was cultured at 0 rpm for about 20 hours. 1 ml of the culture completion liquid
Example 6 after separating each of them into an appropriate centrifuge tube
The nitrile hydratase activity was measured by the same procedure as in. As a result, the production of acrylamide was detected, and clone No. It was confirmed that 42 strains retain the nitrile hydratase activity.

Cells were separated from the remaining 1 ml of the above culture solution used for the measurement of nitrile hydratase activity, and alkali S
The plasmid DNA of each clone was prepared by the DS extraction method. Then, by the same operation as in Example 2, clone N
o. The nucleotide sequence of the nitrile hydratase structural gene of 42 strains was determined. As a result, as shown in Table 42 [Table 42], the 6th Leu of the α subunit of wild-type nitrile hydratase was Thr, the 19th Ala of the α subunit was Val, and the α subunit of 126 was 126 Th P
he is Tyr and the 108th Glu of β subunit
Is Arg and the 212th Ser of the β subunit is T
were each replaced by yr.

[0256]

[Table 42]

[Example 48] Acquisition of amino acid substitution product retaining nitrile hydratase activity (43) Clone No. Amino acid mutation of strain 34 and clone No.
It was confirmed that the nitrile hydratase activity was retained even in the amino acid substitutions having the 39 amino acid mutations.

10 ml of LB liquid medium was prepared in a 30 ml test tube and sterilized by autoclaving at 121 ° C. for 20 minutes. Ampicillin was added to this medium to a final concentration of 100 μg / ml, and then clone No. 1 obtained in Example 44 was used. 39 strains were inoculated with monospores at 37 ° C.
The culture was performed at 300 rpm for about 20 hours. 1 ml of the culture solution
Into a suitable centrifuge tube and then centrifuge (150
The cells were separated by (00 rpm × 5 minutes). Subsequently, the clone No. was extracted from the cells by the alkaline SDS extraction method. 39
The strain's plasmid DNA was prepared.

Clone No. 39 strains of plasmid DNA
The only restriction enzyme sites above are EcoRI and No
After cleaving the plasmid DNA with tI, agarose gel electrophoresis (using Sigma type VII low melting point agarose; agarose concentration 1.0%) was performed to cut out a DNA fragment of about 770 bp from the agarose gel. Similarly, the clone No. prepared in Example 46 was used. Eco which is the only restriction enzyme site on plasmid DNA of 34 strains
After cleaving the plasmid DNA with RI and NotI, agarose gel electrophoresis (Type VII manufactured by Sigma)
Low melting point agarose was used; agarose concentration was 0.7%), and a DNA fragment of about 3.8 kbp was cut out from the agarose gel. Both pieces of agarose cut out (about 0.1g)
Finely crushed and suspended in 1 ml of TE solution, then 5
The agarose was completely melted by incubating at 5 ° C for 1 hour.
The melt was subjected to the same phenol / chloroform extraction and ethanol precipitation as in Example 2 to purify each DNA fragment, and finally dissolved in 10 μl of TE.

[0260] Thus obtained clone No. 39
About 770 bp DNA fragment derived from the strain and clone No. Three
About 3.8 Kbp DNA fragments derived from 4 strains were ligated using a DNA ligation kit (Takara Shuzo) to obtain pP.
T-DB43 was constructed. This pPT-DB43 plasmid DNA was introduced into a competent cell of Escherichia coli HB101 (manufactured by Toyobo Co., Ltd.), and E. coli clone No. 43 strains were obtained.

Clone No. Forty-three strains were inoculated into 10 ml of the activity expression medium of Example 6, one ear of each white bacterium, at 37 ° C.
It was cultured at 0 rpm for about 20 hours. 1 ml of the culture completion liquid
Example 6 after separating each of them into an appropriate centrifuge tube
The nitrile hydratase activity was measured by the same procedure as in. As a result, the production of acrylamide was detected, and clone No. It was confirmed that 43 strains retained nitrile hydratase activity.

The cells were separated from the remaining 1 ml of the above culture solution used for the measurement of nitrile hydratase activity, and alkali S
The plasmid DNA of each clone was prepared by the DS extraction method. Then, by the same operation as in Example 2, clone N
o. The nucleotide sequence of the nitrile hydratase structural gene of 43 strains was determined. As a result, as shown in Table 43 [Table 43], the sixth Leu of the α subunit of the wild-type nitrile hydratase was Thr, the 19th Ala of the α subunit was Val, and the α subunit 126 was 126. Th P
he is Tyr and 200th Ala of β subunit
Is Glu and the 212th Ser of the β subunit is T
were each replaced by yr.

[0263]

[Table 43]

[Example 49] Acquisition of amino acid substitution product retaining nitrile hydratase activity (44) Clone No. Amino acid mutation of strain 34 and clone No.
It was confirmed that the nitrile hydratase activity was retained even in the amino acid substitutions having the 40 amino acid mutations.

10 ml of LB liquid medium was prepared in a 30 ml test tube and sterilized by autoclaving at 121 ° C. for 20 minutes. Ampicillin was added to this medium to a final concentration of 100 μg / ml, and then clone No. 1 obtained in Example 45 was used. 40 strains were inoculated with monospores at 37 ° C.
The culture was performed at 300 rpm for about 20 hours. 1 ml of the culture solution
Into a suitable centrifuge tube and then centrifuge (150
The cells were separated by (00 rpm × 5 minutes). Subsequently, the clone No. was extracted from the cells by the alkaline SDS extraction method. 40
The strain's plasmid DNA was prepared.

Clone No. 40 strains of plasmid DNA
The only restriction enzyme sites above are EcoRI and No
After cleaving the plasmid DNA with tI, agarose gel electrophoresis (using Sigma type VII low melting point agarose; agarose concentration 1.0%) was performed to cut out a DNA fragment of about 770 bp from the agarose gel. Similarly, the clone No. prepared in Example 46 was used. Eco which is the only restriction enzyme site on plasmid DNA of 34 strains
After cleaving the plasmid DNA with RI and NotI, agarose gel electrophoresis (Type VII manufactured by Sigma)
Low melting point agarose was used; agarose concentration was 0.7%), and a DNA fragment of about 3.8 kbp was cut out from the agarose gel. Both pieces of agarose cut out (about 0.1g)
Finely crushed and suspended in 1 ml of TE solution, then 5
The agarose was completely melted by incubating at 5 ° C for 1 hour.
The melt was subjected to the same phenol / chloroform extraction and ethanol precipitation as in Example 2 to purify each DNA fragment, and finally dissolved in 10 μl of TE.

The clone No. thus obtained was 40
About 770 bp DNA fragment derived from the strain and clone No. Three
About 3.8 Kbp DNA fragments derived from 4 strains were ligated using a DNA ligation kit (Takara Shuzo) to obtain pP.
T-DB44 was constructed. This pPT-DB44 plasmid DNA was introduced into a competent cell of Escherichia coli HB101 (manufactured by Toyobo Co., Ltd.), and E. coli clone No. 44 strains were obtained.

Clone No. Forty-four strains were inoculated into 10 ml of the activity expression medium of Example 6, one ear of each white bacterium, at 37 ° C.
It was cultured at 0 rpm for about 20 hours. 1 ml of the culture completion liquid
Example 6 after separating each of them into an appropriate centrifuge tube
The nitrile hydratase activity was measured by the same procedure as in. As a result, the production of acrylamide was detected, and clone No. It was confirmed that 44 strains retain nitrile hydratase activity.

The cells were separated from the remaining 1 ml of the above culture solution used for the measurement of nitrile hydratase activity, and alkali S
The plasmid DNA of each clone was prepared by the DS extraction method. Then, by the same operation as in Example 2, clone N
o. The nucleotide sequence of the nitrile hydratase structural gene of 44 strains was determined. As a result, as shown in Table 44 [Table 44], the sixth Leu of the α subunit of wild-type nitrile hydratase was Thr, the 19th Ala of the α subunit was Val, and the α subunit 126 was 126. Th P
he is Tyr and the 108th Glu of β subunit
Is Arg and the 200th Ala of β subunit is G
The 212th Ser of β subunit is Tyr in lu
Have been replaced respectively.

[0270]

[Table 44]

[0271]

According to the present invention, Pseudonocardia
The amino acid and gene sequences of nitrile hydratase from Thermophila are provided. Also provided are a method for changing the base sequence and the amino acid sequence of the nitrile hydratase without substantially changing the function of the nitrile hydratase, and a nitrile hydratase having the changed base sequence and the amino acid sequence based on the method. . Furthermore, a recombinant plasmid containing the gene, a transformant strain containing the recombinant plasmid, a method for producing the enzyme using the transformant strain, and production of a corresponding amide compound from a nitrile compound using the transformant strain A method is provided.

[0272]

[Sequence list]

SEQ ID NO: 1 Sequence Length: 205 Sequence Type: Amino Acid Topology: Linear Sequence Type: Protein Origin Organism Name: Pseudonocardia thermo
phila Ltd. Name: JCM3095 Direct origin clone name: pPT-DB1 arrangement method to determine the characteristics features: E Other Information: nitrile hydratase α subunit sequence Met Thr Glu Asn Ile Leu Arg Lys Ser Asp Glu Glu Ile Gln Lys Glu 5 10 15 Ile Thr Ala Arg Val Lys Ala Leu Glu Ser Met Leu Ile Glu Gln Gly 20 25 30 Ile Leu Thr Thr Ser Met Ile Asp Arg Met Ala Glu Ile Tyr Glu Asn 35 40 45 Glu Val Gly Pro His Leu Gly Ala Lys Val Val Val Lys Ala Trp Thr 50 55 60 Asp Pro Glu Phe Lys Lys Arg Leu Leu Ala Asp Gly Thr Glu Ala Cys 65 70 75 80 Lys Glu Leu Gly Ile Gly Gly Leu Gln Gly Glu Asp Met Met Trp Val 85 90 95 Glu Asn Thr Asp Glu Val His His Val Val Val Cys Thr Leu Cys Ser 100 105 110 Cys Tyr Pro Trp Pro Val Leu Gly Leu Pro Pro Asn Trp Phe Lys Glu 115 120 125 Pro Gln Tyr Arg Ser Arg Val Val Arg Glu Pro Arg Gln Leu Leu Lys 130 135 140 Glu Glu Phe Gly Phe Glu Val Pro Pro Ser Lys Glu Ile Lys Val Trp 145 150 155 160 Asp Ser Ser Ser Glu Met Arg Phe Val Val Leu Pro Gln Arg Pro Ala 165 170 175 Gly Thr Asp Gly Trp Ser Glu Glu Glu Leu Ala Thr Leu Val Thr Arg 180 185 190 Glu Ser Met Ile Gly Val Glu Pro Ala Lys Ala Val Ala 195 200 205

SEQ ID NO: 2 Sequence Length: 233 Sequence Type: Amino Acid Topology: Linear Sequence Type: Protein Origin Organism Name: Pseudonocardia thermo
phila Ltd. Name: JCM3095 Direct origin clone name: pPT-DB1 arrangement method to determine the characteristics features: E Other Information: nitrile hydratase β subunit sequence Met Asn Gly Val Tyr Asp Val Gly Gly Thr Asp Gly Leu Gly Pro Ile 5 10 15 Asn Arg Pro Ala Asp Glu Pro Val Phe Arg Ala Glu Trp Glu Lys Val 20 25 30 Ala Phe Ala Met Phe Pro Ala Thr Phe Arg Ala Gly Phe Met Gly Leu 35 40 45 Asp Glu Phe Arg Phe Gly Ile Glu Gln Met Asn Pro Ala Glu Tyr Leu 50 55 60 Glu Ser Pro Tyr Tyr Trp His Trp Ile Arg Thr Tyr Ile His His Gly 65 70 75 80 Val Arg Thr Gly Lys Ile Asp Leu Glu Glu Leu Glu Arg Arg Thr Gln 85 90 95 Tyr Tyr Arg Glu Asn Pro Asp Ala Pro Leu Pro Glu His Glu Gln Lys 100 105 110 Pro Glu Leu Ile Glu Phe Val Asn Gln Ala Val Tyr Gly Gly Leu Pro 115 120 125 Ala Ser Arg Glu Val Asp Arg Pro Pro Lys Phe Lys Glu Gly Asp Val 130 135 140 Val Arg Phe Ser Thr Ala Ser Pro Lys Gly His Ala Arg Arg Ala Arg 145 150 155 160 Tyr Val Arg Gly Lys Thr Gly Thr Val Val Lys His His Gly Ala Tyr 165 170 175 Ile Tyr Pro Asp Thr Ala Gly Asn Gly Leu Gly Glu Cys Pro Glu His 180 185 190 Leu Tyr Thr Val Arg Phe Thr Ala Gln Glu Leu Trp Gly Pro Glu Gly 195 200 205 Asp Pro Asn Ser Ser Val Tyr Tyr Asp Cys Trp Glu Pro Tyr Ile Glu 210 215 220 Leu Val Asp Thr Lys Ala Ala Ala Ala 225 230 233

SEQ ID NO: 3 Sequence length: 618 Sequence type: Nucleic acid chain number: Double-stranded topology: Linear Sequence type: Genomic DNA Origin organism name: Pseudonocardia thermo
phila Ltd. Name: JCM3095 Direct origin clone name: pPT-DB1 method to determine the characteristics features of the sequence: E Other Information: nitrile hydratase α subunit sequence ATGACCGAGA ACATCCTGCG CAAGTCGGAC GAGGAGATCC AGAAGGAGAT CACGGCGCGG 60 GTCAAGGCCC TGGAGTCGAT GCTCATCGAA CAGGGCATCC TCACCACGTC GATGATCGAC 120 CGGATGGCCG AGATCTACGA GAACGAGGTC GGCCCGCACC TCGGCGCGAA GGTCGTCGTG 180 AAGGCCTGGA CCGACCCGGA GTTCAAGAAG CGTCTGCTCG CCGACGGCAC CGAGGCCTGC 240 AAGGAGCTCG GCATCGGCGG CCTGCAGGGC GAGGACATGA TGTGGGTGGA GAACACCGAC 300 GAGGTCCACC ACGTCGTCGT GTGCACGCTC TGCTCCTGCT ACCCGTGGCC GGTGCTGGGG 360 CTGCCGCCGA ACTGGTTCAA GGAGCCGCAG TACCGCTCCC GCGTGGTGCG TGAGCCCCGG 420 CAGCTGCTCA AGGAGGAGTT CGGCTTCGAG GTCCCGCCGA GCAAGGAGAT CAAGGTCTGG 480 GACTCCAGCT CCGAGATGCG CTTCGTCGTC CTCCCGCAGC GCCCCGCGGG CACCGACGGG 540 TGGAGCGAGG AGGAGCTCGC CACCCTCGTC ACCCGCGAGT CGATGATCGG CGTCGAACCG 600 GCGAAGGCGG TCGCGTGA 618

SEQ ID NO: 4 Sequence length: 702 Sequence type: Nucleic acid chain number: Double-stranded topology: Linear Sequence type: Genomic DNA Origin organism name: Pseudonocardia thermo
phila Ltd. Name: JCM3095 Direct origin clone name: pPT-DB1 method to determine the characteristics features of the sequence: E Other Information: nitrile hydratase β subunit sequence ATGAACGGCG TGTACGACGT CGGCGGCACC GATGGGCTGG GCCCGATCAA CCGGCCCGCG 60 GACGAACCGG TCTTCCGCGC CGAGTGGGAG AAGGTCGCGT TCGCGATGTT CCCGGCGACG 120 TTCCGGGCCG GCTTCATGGG CCTGGACGAG TTCCGGTTCG GCATCGAGCA GATGAACCCG 180 GCCGAGTACC TCGAGTCGCC GTACTACTGG CACTGGATCC GCACCTACAT CCACCACGGC 240 GTCCGCACCG GCAAGATCGA TCTCGAGGAG CTGGAGCGCC GCACGCAGTA CTACCGGGAG 300 AACCCCGACG CCCCGCTGCC CGAGCACGAG CAGAAGCCGG AGTTGATCGA GTTCGTCAAC 360 CAGGCCGTCT ACGGCGGGCT GCCCGCAAGC CGGGAGGTCG ACCGACCGCC CAAGTTCAAG 420 GAGGGCGACG TGGTGCGGTT CTCCACCGCG AGCCCGAAGG GCCACGCCCG GCGCGCGCGG 480 TACGTGCGCG GCAAGACCGG GACGGTGGTC AAGCACCACG GCGCGTACAT CTACCCGGAC 540 ACCGCCGGCA ACGGCCTGGG CGAGTGCCCC GAGCACCTCT ACACCGTCCG CTTCACGGCC 600 CAGGAGCTGT GGGGGCCGGA AGGGGACCCG AACTCCAGCG TCTACTACGA CTGCTGGGAG 660 CCCTACATCG AGCTCGTCGA CACGAAGGCG GCCGCGGCAT GA 702

SEQ ID NO: 5 Sequence length: 20 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Sequence features: N is A or C or G or T Array ACNGARAAYA TNYTNMGNAA 20

SEQ ID NO: 6 Sequence length: 20 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Sequence features: N is A or C or G or T Array TTNCKNARNA TRTTYTCNGT 20

SEQ ID NO: 7 Sequence length: 20 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Sequence features: N is A or C or G or T Array ATGAAYGGNG TNTAYGANGT 20

SEQ ID NO: 8 Sequence length: 20 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Sequence features: N is A or C or G or T Array ACNTCRTANA CNCCRTTCAT 20

SEQ ID NO: 9 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array AACATCATGC GCAAGTCG 18

SEQ ID NO: 10 Sequence length: 17 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array CAGGAAACAG CTATGAC 17

SEQ ID NO: 11 Sequence length: 20 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array GGCCAGTGCC TAGCTTACAT 18

SEQ ID NO: 12 Sequence length: 17 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array GTTTTCCCAG TCACGAC 18

SEQ ID NO: 13 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array AACATCACGC GCAAGTCG 18

SEQ ID NO: 14 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array AACATCGCGC GCAAGTCG 18

SEQ ID NO: 15 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array AACATCGTGC GCAAGTCG 18

SEQ ID NO: 16 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array ATCACGGTGC GGGTCAAG 18

SEQ ID NO: 17 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array ACGTCGTTGA TCGACCGG 18

SEQ ID NO: 18 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array GACGGCTCCG AGGCCTGC 18

SEQ ID NO: 19 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array CTGCAGGCCG AGGACATG 18

SEQ ID NO: 20 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array GACGAGGCCC ACCACGTC 18

SEQ ID NO: 21 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array CACGTCATCG TGTGCACG 18

SEQ ID NO: 22 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array AACTGGTACA AGGAGCCG 18

SEQ ID NO: 23 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array GAGCCGGAGT ACCGCTCC 18

SEQ ID NO: 24 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array CGGCAGGTGC TCAAGGAG 18

SEQ ID NO: 25 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array AAGGAGGACT TCGGCTTC 18

SEQ ID NO: 26 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array GAGCTCACCA CCCTCGTC 18

SEQ ID NO: 27 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array 18 CGCGAGTTGA TGATCGGC

SEQ ID NO: 28 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array GCGAAGGAGG TCGCGTGA 18

SEQ ID NO: 29 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array CGGCCCGTGG ACGAACCG 18

SEQ ID NO: 30 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array CCCGCGAACG AACCGGTC 18

SEQ ID NO: 31 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array CTGCCCGATC ACGAGCAG 18

SEQ ID NO: 32 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array CTGCCCCCGC ACGAGCAG 18

SEQ ID NO: 33 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array CTGCCCTCGC ACGAGCAG 18

SEQ ID NO: 34 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array CTGCCCCGGC ACGAGCAG 18

SEQ ID NO: 35 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array CTGCCCTGCC ACGAGCAG 18

SEQ ID NO: 36 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array CTGCCCCTGC ACGAGCAG 18

SEQ ID NO: 37 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array CTGCCCACGC ACGAGCAG 18

SEQ ID NO: 38 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array TTCACGGACC AGGAGCTG 18

SEQ ID NO: 39 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array TTCACGATCC AGGAGCTG 18

SEQ ID NO: 40 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array TTCACGGTCC AGGAGCTG 18

SEQ ID NO: 41 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array TTCACGGAGC AGGAGCTG 18

SEQ ID NO: 42 Sequence length: 18 Sequence type: Nucleic acid Number of chains: Single chain Topology: linear Sequence type: Other nucleic acids Synthetic DNA Array CCGAACTACA GCGTCTAC 18

[Brief description of drawings]

FIG. 1 shows a restriction enzyme cleavage point map of plasmid pPT-B1.

FIG. 2 shows a restriction enzyme cleavage point map of plasmid pPT-DB1.

[Explanation of symbols]

The gene encoding Amp: β-lactamase is shown. The replication origin of the ORI: ColE1 system is shown. lacPO: shows the promoter and operator regions of the lactose operon from pUC18. NHα: shows a gene encoding the α subunit of nitrile hydratase from Pseudonocardia thermophila. NHβ: shows a gene encoding the β subunit of nitrile hydratase from Pseudonocardia thermophila. (XbaI / NspV): shows a self-ligation site after blunting between the XbaI and NspV sites.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI (C12N 9/88 C12R 1:19) (C12N 15/09 ZNA C12R 1:01) (72) Inventor Takeshi Nakamura Mobara City, Chiba Prefecture 1144 Togo Mitsui Toatsu Kagaku Co., Ltd. (58) Fields investigated (Int.Cl. ⁷ , DB name) C12N 9/88 C12N 1/21 C12N 15/00-15/90 BIOSIS / WPI (DIALOG) SwissProt / PIR / GeneS eq GenBank / EMBL / DDBJ / Gene Seq

Claims (21)

(57) [Claims] 1. A nitrile hydratase composed of an α subunit represented by the amino acid sequence of SEQ ID NO: 1 in the sequence listing and a β subunit represented by the amino acid sequence of SEQ ID NO: 2 of the sequence listing. 2. An α obtained by substituting, deleting, deleting or inserting a part of the amino acid sequence represented by SEQ ID NO: 1 in the Sequence Listing.
Β obtained by substituting, deleting, deleting or inserting a subunit and part of the amino acid sequence of SEQ ID NO: 2 in Sequence Listing
Nitrile hydratase containing a subunit as a constituent. 3. Pseudonocardia thermophila (P
The nitrile hydratase according to claim 1 or 2, which is derived from seudonocardia thermophila JCM3095). 4. The 6th, 19th, 38th, 77th, 90th, 102nd, 106th, 126th, 130th, 142nd, 146th, of the amino acid sequence of SEQ ID NO: 1 in the sequence listing. A nitrile hydratase containing, as a constituent, an α subunit obtained by substituting one or more amino acids of the 187th, 194th and 203rd amino acids with another amino acid. 5. The 20th, 21st, 108th, 200th, 2nd amino acid sequence of SEQ ID NO: 2 in the sequence listing.
A nitrile hydratase containing as a constituent a β subunit obtained by substituting any one or more amino acids of the 12th amino acid with other amino acids. 6. A gene encoding the α-subunit of the nitrile hydratase according to claim 1. 7. A gene encoding the α subunit of the nitrile hydratase according to claim 2. 8. A gene encoding the α subunit of nitrile hydratase represented by the nucleotide sequence set forth in SEQ ID NO: 3 in Sequence Listing. 9. A gene encoding an α subunit of nitrile hydratase represented by a nucleotide sequence obtained by substituting, deleting, deleting or inserting a part of the nucleotide sequence of SEQ ID NO: 3 in Sequence Listing. . 10. The 16th to 18th, 55th to 57th, 1st of the nucleotide sequence of SEQ ID NO: 3 in the Sequence Listing
12th to 114th, 229th to 231,
268th to 270th, 304th to 306th, 316th to 318th, 376th to 378th
Th, 388th to 390th, 424th to 42nd
6th, 436th to 438th, 559th to 5th
It encodes the α subunit of nitrile hydratase represented by a nucleotide sequence obtained by substituting one or more nucleotide sequences of 61st, 580th to 582th, and 607th to 609th with other nucleotide sequences. gene. 11. A gene encoding the β subunit of the nitrile hydratase according to claim 1. 12. A gene encoding the β subunit of the nitrile hydratase according to claim 2. 13. A gene encoding the β subunit of nitrile hydratase represented by the nucleotide sequence set forth in SEQ ID NO: 4 in Sequence Listing. 14. A gene encoding a β subunit of nitrile hydratase represented by a nucleotide sequence obtained by substituting, deleting, deleting or inserting a part of the nucleotide sequence of SEQ ID NO: 4 in Sequence Listing. . 15. The 58th position to the 60th position, the 61st position to the 63rd position, and the 3rd position of the base sequence set forth in SEQ ID NO: 4 in the Sequence Listing.
22nd to 324th, 598th to 600th,
A gene encoding the β subunit of nitrile hydratase represented by a nucleotide sequence obtained by substituting one or more nucleotide sequences from the 634th to 636th with another nucleotide sequence. 16. A gene encoding the α subunit of the nitrile hydratase according to any one of claims 6 to 10 or β of the nitrile hydratase according to any one of claims 11 to 15.
A recombinant plasmid containing any of the genes encoding the subunits. 17. A gene encoding the α-subunit of the nitrile hydratase according to claims 6 to 10 and β of the nitrile hydratase according to claims 11 to 15.
A recombinant plasmid containing a gene encoding a subunit. 18. A transformant carrying the recombinant plasmid according to claim 16. 19. A transformant carrying the recombinant plasmid according to claim 17. 20. A nitrile characterized by culturing the transformant according to claim 18 or 19, and recovering nitrile hydratase from the transformant obtained by the culturing, the culture solution, and a treated product thereof. Method for producing hydratase. 21. A transformant strain according to claim 18 or 19 is cultured, and a transformant strain, a culture solution obtained by the culture, a treated product thereof, or a nitrile hydratase and a nitrile compound obtained from them are obtained. Is contacted in an aqueous medium to produce an amide compound corresponding to the nitrile compound.