CN110699341A - Microbial aminopeptidase and preparation and application thereof - Google Patents

Microbial aminopeptidase and preparation and application thereof Download PDF

Info

Publication number
CN110699341A
CN110699341A CN201910951340.5A CN201910951340A CN110699341A CN 110699341 A CN110699341 A CN 110699341A CN 201910951340 A CN201910951340 A CN 201910951340A CN 110699341 A CN110699341 A CN 110699341A
Authority
CN
China
Prior art keywords
aminopeptidase
protein
culturing
kana
microbial
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201910951340.5A
Other languages
Chinese (zh)
Inventor
程昌勇
宋厚辉
孙静
杭奕
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Zhejiang A&F University ZAFU
Original Assignee
Zhejiang A&F University ZAFU
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Zhejiang A&F University ZAFU filed Critical Zhejiang A&F University ZAFU
Priority to CN201910951340.5A priority Critical patent/CN110699341A/en
Publication of CN110699341A publication Critical patent/CN110699341A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N9/00Enzymes; Proenzymes; Compositions thereof; Processes for preparing, activating, inhibiting, separating or purifying enzymes
    • C12N9/14Hydrolases (3)
    • C12N9/48Hydrolases (3) acting on peptide bonds (3.4)
    • C12N9/485Exopeptidases (3.4.11-3.4.19)
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N15/00Mutation or genetic engineering; DNA or RNA concerning genetic engineering, vectors, e.g. plasmids, or their isolation, preparation or purification; Use of hosts therefor
    • C12N15/09Recombinant DNA-technology
    • C12N15/63Introduction of foreign genetic material using vectors; Vectors; Use of hosts therefor; Regulation of expression
    • C12N15/70Vectors or expression systems specially adapted for E. coli
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12YENZYMES
    • C12Y304/00Hydrolases acting on peptide bonds, i.e. peptidases (3.4)
    • C12Y304/11Aminopeptidases (3.4.11)

Landscapes

  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Genetics & Genomics (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Wood Science & Technology (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • Zoology (AREA)
  • General Engineering & Computer Science (AREA)
  • General Health & Medical Sciences (AREA)
  • Biotechnology (AREA)
  • Biochemistry (AREA)
  • Biomedical Technology (AREA)
  • Microbiology (AREA)
  • Molecular Biology (AREA)
  • Medicinal Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Biophysics (AREA)
  • Plant Pathology (AREA)
  • Enzymes And Modification Thereof (AREA)

Abstract

The invention relates to genetic engineering and biological enzyme technology, and aims to provide a microbial aminopeptidase and preparation and application thereof. The amino acid sequence of the aminopeptidase is shown as SEQ ID NO.1, and the aminopeptidase can be used as a hydrolase of protein or polypeptide in the food industry and the biopharmaceutical industry. The invention is realized by adopting gene engineering expression, overcomes the defect of low aminopeptidase content in natural bacteria, and can be fermented in batch; the soluble expression form avoids the disadvantage that other proteases of microbial origin are inclusion bodies. The protease is widely present in organisms of different species; has the functions of improving the flavor of food, preparing bioactive peptide, specifically eliminating nerve chemical toxic agent, etc. The physical characteristics of the protein are soluble forms, and the natural activity is retained, so that the protein has a wide application scene.

Description

Microbial aminopeptidase and preparation and application thereof
Technical Field
The invention belongs to gene engineering and biological enzyme technology, and particularly relates to preparation and application of microbial aminopeptidase.
Background
Aminopeptidases (APs for short, EC 3.4.11) are exoproteases that selectively cleave amino acid residues from the N-terminus of proteins and polypeptides to produce free amino acids, and are widely found in organisms of various species, including mammals, plants, microorganisms, and the like. Because of the variety of aminopeptidases, which modify the N-terminal residues of various proteins, the proteases have wide applications in the food industry and biopharmaceuticals. For example, the method can be used for removing the bitter taste of protein hydrolysate, the protein hydrolysate hydrolyzed by protease usually has the bitter taste, and the bitter taste can be removed by further hydrolyzing the protein hydrolysate by aminopeptidase; the deep hydrolysis of the protein, the compound use of aminopeptidase and protease, can greatly improve the degree of hydrolysis of the protein, in the preparation process of soy sauce brewing, cheese production and other protein hydrolysis products, can improve the utilization ratio of the protein, save the cost; the preparation of bioactive polypeptide can be carried out by controlling the enzymolysis of protein, the bioactive polypeptide is mostly cell growth factor, the content of the bioactive polypeptide in the body is extremely low, but the bioactivity is extremely high, and the bioactive polypeptide has the functions of health care and beauty treatment. Because of its high production and application value, the research on aminopeptidase has been more and more focused.
Currently, commercially available aminopeptidases are mainly produced by extraction from animals and plants and microbiological methods. The extraction of aminopeptidase from animals and plants is generally mainly used for characterization of enzymology properties and diagnosis of related diseases; in the latter case, although there are many kinds of aminopeptidase-producing microorganisms, most of the strains are not suitable for mass production of aminopeptidase due to low enzyme-producing ability or potential safety hazard.
Disclosure of Invention
The invention aims to solve the technical problem of overcoming the defects in the prior art and provides a microbial aminopeptidase and preparation and application thereof.
In order to solve the technical problem, the solution of the invention is as follows:
provides a microbial aminopeptidase, the amino acid sequence of the aminopeptidase is shown in SEQ ID NO. 1.
The invention further provides the use of said aminopeptidase in the food industry and in the biopharmaceutical industry as a hydrolase for proteins or polypeptides.
The invention also provides a preparation method of the protease, which is characterized in that genome DNA of a wild Listeria monocytogenes strain is used as a template to carry out PCR amplification reaction to obtain a target fragment containing an aminopeptidase target gene and containing a restriction enzyme cutting site; carrying out double enzyme digestion on a target gene and a vector by using restriction enzymes Kpn I and BamH I, and then connecting the target gene into an expression vector pET30a (+); transforming the ligation product into competent cells E.coli DH5 alpha, and culturing on Kana/LB solid agar medium; putting the positive cloning recombinant bacterium plasmid into a competent cell E.coli Rosetta, taking a monoclonal colony for amplification culture, and separating and purifying to obtain a recombinant protein, namely the microbial aminopeptidase, through ultrasonic disruption, imidazole elution and nickel ion resin column affinity chromatography.
In the invention, the preparation method specifically comprises the following steps:
(1) amplifying the genome DNA of a Listeria wild strain by using a specific primer, and designing enzyme cutting sites of Kpn I and BamH I on the primer while amplifying, wherein the sequences of the specific primer are respectively as follows:
an upstream primer: 5'-CGGGGTACCATGACAGTATTTAGTGAAAAGTTAGAAAAGTATGC-3', respectively;
a downstream primer: 5'-CGCGGATCCTTAGAACGCCCAGTCGCCTTTA-3', respectively;
the PCR amplification system used was: KOD-plus-Neo 1. mu.L, 10 XPCR Buffer for KOD-plus-Neo 5. mu.L, MgSO4mu.L, dNTPs 5. mu.L, upstream primer 1. mu.L, downstream primer 1. mu.L, DNA template 2. mu.L, plus ddH2O to 50 μ L; the PCR amplification conditions were: pre-denaturation at 94 ℃ for 30s, denaturation at 98 ℃ for 10s, annealing at 55 ℃ for 30s, extension at 68 ℃ for 1min for 30s, circulation for 25-35 times, and extension at 68 ℃ for 8-12 min;
(2) respectively carrying out double digestion on pET30a (+) plasmid and amplification product by using restriction enzymes Kpn I and BamH I, recovering the target product after electrophoresis, and then carrying out overnight connection at 16 ℃ by using T4 DNA ligase to connect the target gene with the vector; transforming the ligation product into a competent cell E.coli DH5 alpha, coating the competent cell E.coli DH5 alpha on a Kana/LB agar solid culture medium, and culturing overnight at 37 ℃ to obtain a recombinant strain; culturing in Kana/LB agar solid culture medium with kanamycin concentration of 50mg/L and agar concentration of 1.5%;
(3) selecting the recombinant strain to be monoclonal to 5mL Kana/LB agar liquid culture medium, and staying overnight at 37 ℃; extracting plasmid after culturing, and sequencing;
(4) transforming the plasmid with correct sequencing into E.coli Rosetta, and culturing overnight; then, the recombinant strain is selected to be monoclonal to 500mL Kana/LB culture medium, and cultured at 37 ℃ and 150 r/min; culturing to OD600 nmWhen the concentration is 0.6, adding IPTG with the final concentration of 0.6mM, and inducing for 8 hours at 30 ℃ at the speed of 100-300 r/min to obtain protein induction expression bacterial liquid; centrifuging the bacterium liquid 3700r/min for 15min, discarding the supernatant, and collecting the precipitate; then adding 30mL of 50mM PBS, and using a cell ultrasonic crusher to crack cells; centrifuging at 3700r/min for 15min to collect supernatant, combining the supernatant with nickel column at 4 deg.C for 4h, and purifying with column; eluting the hybrid protein by using 30mL of 50mM imidazole, and eluting the target protein by using 6-8mL of 400mM imidazole to finally obtain the purified active protein, namely the microbial aminopeptidase.
Compared with the prior art, the invention has the beneficial effects that:
1. the aminopeptidase in the invention selects mature commercial engineering bacteria escherichia coli Rosetta for expression, and the bacteria have the characteristics of safety, stable expression and easy culture; the preparation technology of the microbial aminopeptidase is realized by adopting genetic engineering expression, overcomes the defect of low aminopeptidase content in natural bacteria, and can realize batch fermentation; meanwhile, the aminopeptidase in the invention is in a soluble expression form, so that the defect that other microbial protease is inclusion body is avoided. The aminopeptidase of the present invention was tested in a number of repeated experiments to confirm that it had aminopeptidase activity.
2. The microbial aminopeptidase of the present invention belongs to the aminopeptidase M29 family II, and is derived from Listeria monocytogenes. The protease is an exoprotease which can selectively cut off amino acid residues from the N end of proteins and polypeptides to generate free amino acids, and is widely present in organisms of different species, including mammals, plants, microorganisms and the like. Aminopeptidases are diverse in kind and can modify the N-terminal residues of a wide variety of proteins. On one hand, in bacteria and cells, the protease plays a role in participating in modification and maturation of target proteins, antigen presentation of immune cells and detection indexes of liver and kidney injury; on the other hand, in industrial applications, the aminopeptidase has functions of food flavor improvement, preparation of bioactive peptides, specific elimination of nerve chemical poisons, and the like.
3. The recombinant strain constructed by the method can efficiently and rapidly express active protein, the target protein is high in yield, the protein has high aminopeptidase activity, better technical support is provided for industrial production, food processing and medical health care of the protease, and the recombinant strain has higher research and potential application values.
4. The physical characteristics of the microbial aminopeptidase are characterized by a soluble form, and natural activity is retained, so that the microbial aminopeptidase has a wide application scene.
Drawings
Fig. 1 shows the induced expression and purification of recombinant protein in e.
In the figure, M is a protein Marker, and 1, 2, 3, 4 and 5 are purified recombinant proteins.
Detailed Description
The Listeria monocytogenes wild strain refers to an EGD-e strain, and the strain is a standard strain purchased from ATCC.
The main reagents are as follows: LB medium, agarose H, agar, imidazole, ampicillin, kanamycin, IPTG were purchased from Shanghai Biotech, BHI medium was purchased from Oxoid, UK, KOD-plus-Neo (PCR kit) was purchased from TOYOBO, PCR product purification/recovery kit was purchased from Shanghai Rier maple Biotech, Inc., restriction endonuclease was purchased from NEB, T4 ligase was purchased from Takara, plasmid extraction kit was purchased from Tiangen Biochemical, Inc.
The main apparatus is as follows: shaking table (HZ-9211K), vortex oscillator (ZEALWAY GI541), multifunctional enzyme labeling instrument (BioTek SynergyTM H1), gradient PCR instrument (Eppendorf), gel imaging system (UVP), metal bath (Thermo), biological safety cabinet (BSC-II), protein electrophoresis instrument (BIORAD)
The technical solution of the present invention is further explained by the following embodiments with reference to the attached drawings, but the scope of the present invention is not limited in any way by the embodiments.
1. Construction of recombinant expression bacteria
(1) Specific primers (SEQ ID NO.2 and SEQ ID NO.3) are adopted to amplify the genome DNA of a Listeria wild strain (such as EGDe standard strain of ATCC or other Listeria standard strains), and Kpn I and BamH I enzyme cutting sites are designed on the primers during amplification, wherein the amplification primers are as follows:
SEQ ID NO.2:
upstream primer 5'-CGGGGTACCATGACAGTATTTAGTGAAAAGTTAGAAAAGTATGC-3'
SEQ ID NO.3:
Downstream primer 5'-CGCGGATCCTTAGAACGCCCAGTCGCCTTTA-3'
The PCR amplification system is as follows: KOD-plus-Neo 1. mu.L, 10 XPCR Buffer for KOD-plus-Neo 5. mu.L, MgSO4mu.L, dNTPs 5. mu.L, upstream primer 1. mu.L, downstream primer 1. mu.L, DNA template 2. mu.L, plus ddH2O to 50. mu.L. The PCR amplification conditions were: pre-denaturation at 94 ℃ for 30s, denaturation at 98 ℃ for 10s, annealing at 55 ℃ for 30s, extension at 68 ℃ for 1min for 30s, circulation for 25-35 times, and extension at 68 ℃ for 8-12 min.
(2) The plasmid pET30a (+) and the amplification product are respectively cut by restriction enzymes Kpn I and BamH I, and the target product is recovered after 1% electrophoresis. The gene of interest was then ligated to the vector using T4 DNA ligase overnight at 16 ℃. Finally, the ligation product is transformed into a competent cell E.coli DH5 alpha, coated on a Kana/LB agar solid culture medium, kept stand at 37 ℃ and cultured overnight to obtain a recombinant strain; the culture was carried out in Kana/LB agar solid medium, kanamycin concentration was 50mg/L, and agar concentration was 1.5%.
(3) The recombinant strain is selected to be monoclonal to 5mL Kana/LB liquid culture medium, cultured overnight at 37 ℃ at 150r/min, and then identified by methods such as PCR, double enzyme digestion plasmid, sequencing and the like.
2. Expression and purification of recombinant proteins
And (3) transforming the positive plasmid with correct sequencing into an escherichia coli competent cell E. The recombinant strain is selected to be monoclonally cultured in 5mL liquid Kana/LB culture medium for overnight culture, and then 1mL bacterial liquid is taken to be transferred into 500mL Kana/LB culture medium for fermentation culture at 37 ℃ and 150 r/min. Culturing to OD600nmWhen the concentration is 0.6, adding IPTG with the final concentration of 0.6mM, and inducing for 8 hours at 30 ℃ at the speed of 100-300 r/min to obtain the protein induction expression bacterial liquid. Centrifuging the bacterial solution 3700r/min for 15min, discarding the supernatant, collecting the precipitate, adding 30mL of 50mM PBS, lysing the cells with a cell ultrasonication instrument, centrifuging 3700r/min for 15min, collecting the supernatant, combining the supernatant with a nickel column at 4 ℃, 4h, and purifying with a column. The purified active protein (i.e., the microbial aminopeptidase of the present invention) is finally obtained by eluting the hybrid protein with 30mL of 50mM imidazole and eluting the target protein with 6-8mL of 400mM imidazole.
The initial LB culture medium comprises, by mass, 0.9-1.6% of tryptone, 0.8-1.4% of sodium chloride, 0.5-0.7% of yeast extract, and the balance of deionized water.
The purity of the active protein was checked by SDS-PAGE.
The amino acid sequence of the aminopeptidase was determined as follows: (1-410aa)
The format of the triple codon of the amino acid sequence is shown as SEQ ID NO. 1.
3. Protease activity assay
The exoenzyme activity of the aminopeptidase is performed by a method of hydrolyzing amino acid p-nitroaniline.
The specific method comprises the following steps: in a 96-well plate, 200. mu.l of a reaction system was added with 25mM Tris-HCl buffer, 0.5. mu.M purified aminopeptidase and 1mM amino acid p-nitroaniline, respectively, and OD was measured with a microplate reader405nmDetecting absorbance value, setting 3 parallel experiments and enzyme labeling for each reactionThe reading interval of the instrument is 1h, and the reading is continuously carried out for 12 h. Through repeated determination, the aminopeptidase in the invention respectively takes Leu-pNA, Arg-pNA and Lys-pNA as substrates, and utilizes the Mie's equation to obtain the enzyme activity reaction efficiency parameter kcat/KmThe values are 3.149X 10 respectively5min-1M-1、1.536×105min-1M-1And 1.035X 104min-1M-1. This shows that the aminopeptidase of the present invention has strong aminopeptidase activity and wide substrate selectivity, and can recognize and cut various N-terminal residues of protein or polypeptide, so as to hydrolyze and modify protein, and has the highest leucine residue hydrolyzing efficiency.
In the production of hydrolyzed proteins or polypeptides actually used in the food industry and biopharmaceutical industry, the aminopeptidase of microbial origin of the present invention should be present in liquid form.
Sequence listing
<110> Zhejiang agriculture and forestry university
<120> microbial aminopeptidase, and preparation and application thereof
<160>3
<170>SIPOSequenceListing 1.0
<210>1
<211>410
<212>PRT
<213> Artificial Sequence (Artificial Sequence)
<400>1
Met Thr Val Phe Ser Glu Lys Leu Glu Lys Tyr Ala Glu Leu Ile Val
1 5 10 15
Lys Val Gly Val Asn Val Gln Pro Glu Gln Lys Val Val Ile Met Ala
20 25 30
Pro Val Asp Ala Ala Pro Leu Val Arg Leu Ile Ser Lys Tyr Ala Phe
35 40 45
Glu Val Gly Ala Glu Asp Val Ile Met Asp Trp Arg Asp Glu Glu Leu
50 55 60
Gly Ala Leu Arg Tyr Lys Asn Ala Pro Leu Arg Val Phe Glu Ser Ala
65 70 75 80
Pro Val His Arg Val Ala Glu Lys Thr Glu Leu Ala Lys Glu Gly Ala
85 90 95
Cys Phe Ile Ser Ile Thr Ser Glu Asp Pro Asp Leu Leu Asn Gly Val
100 105110
Asp Ser Asn Lys Ile Ala Thr Phe Gln Lys Thr Met Gly Gly Ala Met
115 120 125
Ser Glu Phe Arg Glu Leu Met Gln Ala Asn Val Val Ser Trp Thr Val
130 135 140
Val Ala Ala Ala Ser Gln Gly Trp Ala Ala Lys Val Phe Pro Asp Leu
145 150 155 160
Thr Pro Ala Glu Gln Met Glu Thr Leu Trp Glu Ala Ile Phe Glu Thr
165 170 175
Thr Arg Ile Asn Thr Glu Asn Pro Val Glu Thr Trp Lys Asn His Asp
180 185 190
Gln Thr Leu Ala Ala Lys Ala Glu Ser Leu Asn Glu Lys Gln Phe Thr
195 200 205
Ser Leu His Tyr Thr Ala Pro Gly Thr Asp Leu Thr Ile Gly Leu Pro
210 215 220
Lys Asn His Leu Trp Val Gly Ala Gly Ser Lys Asn Lys Lys Gly His
225 230 235 240
Glu Phe Met Ala Asn Met Pro Thr Glu Glu Val Phe Cys Cys Ala Asp
245 250 255
Lys Leu Lys Val Glu Gly Tyr Val Ser Ser Thr Lys Pro Leu Ser Tyr
260 265 270
Ala Gly Asn Ile Ile Asp Asp Phe Lys Ile Thr Phe Glu Lys Gly Arg
275 280 285
Ile Val Gly Val Glu Ala Ala Ser Gly Glu Glu Ile Leu Lys Asp Leu
290 295 300
Ile Ala Thr Asp Glu Gly Ser His Tyr Leu Gly Glu Val Ala Leu Val
305 310 315 320
Pro Asp Pro Ser Pro Ile Ser Gln Ser Gly Ile Leu Phe Tyr Asn Thr
325 330 335
Leu Phe Asp Glu Asn Ala Ser Asn His Leu Ala Ile Gly Ser Ala Tyr
340 345 350
Ala Phe Asn Val Lys Gly Gly Glu Glu Met Ser Arg Glu Glu Leu Glu
355 360 365
Ala Ala Gly Val Asn Asn Ser Leu Thr His Val Asp Phe Met Ile Gly
370 375 380
Ser Ser Glu Met Asp Ile Asp Gly Val Thr Glu Ser Gly Glu Val Val
385 390 395 400
Pro Val Phe Arg Lys Gly Asp Trp Ala Phe
405 410
<210>2
<211>44
<212>DNA
<213> Artificial Sequence (Artificial Sequence)
<400>2
cggggtacca tgacagtatt tagtgaaaag ttagaaaagt atgc 44
<210>3
<211>31
<212>DNA
<213> Artificial Sequence (Artificial Sequence)
<400>3
cgcggatcct tagaacgccc agtcgccttt a 31

Claims (4)

1. An aminopeptidase derived from a microorganism, wherein the amino acid sequence of the aminopeptidase is represented by SEQ ID NO. 1.
2. Use of the aminopeptidase of claim 1 as a hydrolase for proteins or polypeptides in the food industry and biopharmaceutical industry.
3. The method for producing aminopeptidase of claim 1, wherein a PCR amplification reaction is carried out using a genomic DNA of a wild-type strain of Listeria monocytogenes as a template to obtain a target fragment containing an aminopeptidase target gene and a cleavage site of the aminopeptidase target gene; carrying out double enzyme digestion on a target gene and a vector by using restriction enzymes Kpn I and BamH I, and then connecting the target gene into an expression vector pET30a (+); transforming the ligation product into competent cells E.coli DH5 alpha, and culturing on Kana/LB solid agar medium; putting the positive cloning recombinant bacterium plasmid into a competent cell E.coli Rosetta, taking a monoclonal colony for amplification culture, and separating and purifying to obtain a recombinant protein, namely the microbial aminopeptidase, through ultrasonic disruption, imidazole elution and nickel ion resin column affinity chromatography.
4. The method according to claim 3, characterized in that it comprises in particular the steps of:
(1) amplifying the genome DNA of a Listeria wild strain by using a specific primer, and designing enzyme cutting sites of Kpn I and BamH I on the primer while amplifying, wherein the sequences of the specific primer are respectively as follows:
an upstream primer: 5'-CGGGGTACCATGACAGTATTTAGTGAAAAGTTAGAAAAGTATGC-3', respectively; a downstream primer: 5'-CGCGGATCCTTAGAACGCCCAGTCGCCTTTA-3', respectively;
the PCR amplification system is as follows: KOD-plus-Neo 1. mu.L, 10 XPCR Buffer for KOD-plus-Neo 5. mu.L, MgSO4mu.L, dNTPs 5. mu.L, upstream primer 1. mu.L, downstream primer 1. mu.L, DNA template 2. mu.L, plus ddH2O to 50 μ L; the PCR amplification conditions were: pre-denaturation at 94 ℃ for 30s, denaturation at 98 ℃ for 10s, annealing at 55 ℃ for 30s, extension at 68 ℃ for 1min for 30s, circulation for 25-35 times, and extension at 68 ℃ for 8-12 min;
(2) respectively carrying out double digestion on pET30a (+) plasmid and amplification product by using restriction enzymes Kpn I and BamH I, recovering the target product after electrophoresis, and then carrying out overnight connection at 16 ℃ by using T4 DNA ligase to connect the target gene with the vector; transforming the ligation product into a competent cell E.coli DH5 alpha, coating the competent cell E.coli DH5 alpha on a Kana/LB agar solid culture medium, and culturing overnight at 37 ℃ to obtain a recombinant strain; culturing in Kana/LB agar solid culture medium with kanamycin concentration of 50mg/L and agar concentration of 1.5%;
(3) selecting the recombinant strain to be monoclonal to 5mL Kana/LB agar liquid culture medium, and staying overnight at 37 ℃; extracting plasmid after culturing, and sequencing;
(4) transforming the plasmid with correct sequencing into E.coli Rosetta, and culturing overnight; then, the recombinant strain is selected to be monoclonal to 500mL Kana/LB culture medium, and cultured at 37 ℃ and 150 r/min; culturing to OD600nmWhen the concentration is 0.6, adding IPTG with the final concentration of 0.6mM, and inducing for 8 hours at 30 ℃ at the speed of 100-300 r/min to obtain protein induction expression bacterial liquid; centrifuging the bacterium liquid 3700r/min for 15min, discarding the supernatant, and collecting the precipitate; then adding 30mL of 50mM PBS, and using a cell ultrasonic crusher to crack cells; centrifuging at 3700r/min for 15min to collect supernatant, combining the supernatant with nickel column at 4 deg.C for 4h, and purifying with column; the heteroprotein was eluted using 30mL, 50mM imidazole and thenEluting the target protein by using 6-8mL of 400mM imidazole to finally obtain the purified active protein, namely the microbial aminopeptidase.
CN201910951340.5A 2019-10-08 2019-10-08 Microbial aminopeptidase and preparation and application thereof Pending CN110699341A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910951340.5A CN110699341A (en) 2019-10-08 2019-10-08 Microbial aminopeptidase and preparation and application thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910951340.5A CN110699341A (en) 2019-10-08 2019-10-08 Microbial aminopeptidase and preparation and application thereof

Publications (1)

Publication Number Publication Date
CN110699341A true CN110699341A (en) 2020-01-17

Family

ID=69199035

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910951340.5A Pending CN110699341A (en) 2019-10-08 2019-10-08 Microbial aminopeptidase and preparation and application thereof

Country Status (1)

Country Link
CN (1) CN110699341A (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102492646A (en) * 2011-11-22 2012-06-13 江南大学 Recombination escherichia coli for producing aminopeptidase with high yield and construction method of recombination escherichia coli
CN107254452A (en) * 2017-05-19 2017-10-17 浙江农林大学 A kind of preparation and application of the anti-oxidant protease of microbial source
CN107400666A (en) * 2017-09-11 2017-11-28 广东轻工职业技术学院 A kind of aminopeptidase and its encoding gene and application
CN107603937A (en) * 2017-05-18 2018-01-19 江南大学 A kind of recombination bacillus coli and its construction method for expressing lysine aminopeptidase

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102492646A (en) * 2011-11-22 2012-06-13 江南大学 Recombination escherichia coli for producing aminopeptidase with high yield and construction method of recombination escherichia coli
CN107603937A (en) * 2017-05-18 2018-01-19 江南大学 A kind of recombination bacillus coli and its construction method for expressing lysine aminopeptidase
CN107254452A (en) * 2017-05-19 2017-10-17 浙江农林大学 A kind of preparation and application of the anti-oxidant protease of microbial source
CN107400666A (en) * 2017-09-11 2017-11-28 广东轻工职业技术学院 A kind of aminopeptidase and its encoding gene and application

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
NCBI: "MULTISPECIES: aminopeptidase [Listeria]", 《NCBI REFERENCE SEQUENCE: WP_003728252.1》 *

Similar Documents

Publication Publication Date Title
CN112831485B (en) Low-temperature activity improved exoinulase mutant MutDR121EH9
CN113862233B (en) Method for improving acid stability of glucose oxidase, mutant Q241E/R499E, gene and application
CN111676203B (en) Leucine dehydrogenase mutant and application thereof
CN110527677B (en) Zearalenone hydrolase mutant ZHDM2 and coding gene and application thereof
CN112458072B (en) Alkaline protease mutant and preparation thereof
CN108841851B (en) Method for expressing glutamine transaminase by using food-source-safe host
CN111440782B (en) Beta-galactosidase GalA and application thereof
KR101026526B1 (en) Method for the secretory production of heterologous protein in Escherichia coli
CN108118036A (en) Novel grape carbohydrate oxidase mutant
CN111944790B (en) Neutral protease gene, neutral protease, preparation method and application thereof
CN111676211B (en) Trypsin mutant with autogenous cutting resistance and high specific activity
CN110862978B (en) Preparation method of recombinant halophilic archaea protease
CN101605807A (en) The expression system for recombinant human arginase i of improvement
CN110699341A (en) Microbial aminopeptidase and preparation and application thereof
CN110551697A (en) Application of ergothioneine synthetase PEGT1 and PEGT2 of Pleurotus ostreatus in synthesis of ergothioneine
CN113736766B (en) Collagen hydrolase and its coding gene, preparation method and use
CN111549007B (en) Transaminase TSTA, preparation method and application
CN115029328A (en) Glucose oxidase mutant GOx-MUT 1-6 and coding gene and application thereof
CN114045276A (en) Neutral zearalenone degrading enzyme mutant with improved specific enzyme activity
CN113736762A (en) alpha-L-rhamnosidase mutant and application thereof in preparation of praonine
CN109161539B (en) Organic solvent-tolerant aminopeptidase LapA and preparation method and application thereof
KR102026836B1 (en) Novel lipase gene Lip-1420 derived from soil metagenome and use thereof
CN110872582B (en) Cold-adapted peroxide reductase and coding gene and application thereof
CN112852788A (en) Subtilisin E mutant with improved alkaline substrate selectivity and application thereof
CN115161307B (en) Specific carboxypeptidase for preparing high F value oligopeptide from aspergillus oryzae

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination