CN102154190A - Engineering escherichia coli capable of efficiently producing hyaluronic acid and preparation method thereof - Google Patents

Abstract

The invention provides an engineering escherichia coli capable of efficiently producing hyaluronic acid (HA) and a preparation method thereof. The engineering escherichia coli is obtained by transferring escherichia coli through constructing recombinant expression vector commonly expressed in escherichia coli by gene Has containing HA synthetase and gene containing uridine diphosphate glucose phosphate dehydrogenate. The engineering escherichia coli capable of efficiently producing HA, provided by the invention, is pHK/JM109 with CGMCC No.3926. The engineering escherichia coli provided by the invention can produce 29-2.5g/L of HA. Compared with the yield in the prior art, the highest yield of HA obtained from gene spHas synthesized by Gram positive strep HA which is expressed in escherichia coli is enhanced by about more than 10 times.

Description

A kind of efficient product hyaluronic acid engineering colon bacillus and preparation method thereof

Technical field

The present invention relates to the gene engineering technology field of microorganism, specifically is efficient product hyaluronic acid engineering colon bacillus that makes up with the plasmid form or in the genome conformity mode and preparation method thereof.

Background technology

E. coli k-12 strain system because of genetic background clearly, have numerous genetic transformation systems efficiently and genomic ease for operation is widely used in the metabolic engineering field, to produce high value added product miscellaneous.Do not find as yet at present that natural coli strain has the hyaluronic ability of production.

(Hyaluronic acid HA) separates obtain a kind of and has the high viscosity glycosaminoglycan hyaluronic acid the earliest from buphthalmos.Hyaluronic acid extensively exists in the humans and animals tissue, and its molecular weight is 5 * 10 ⁴To 8 * 10 ⁶Between the dalton, be by β-1, glucuronic acid and β-1 that the 4-glycosidic link connects, nitrogen acetylglucosamine (the β 1-4 D-Glucuronic acid that the 3-glycosidic link connects, GlcA, β 1-3 D-N-acetylglucosamine, the straight-chain polymer that GlcNAc) alternately is formed by connecting.Studies confirm that this polysaccharide has participated in numerous physiological activities such as mammiferous fertilization, fetal development, revascularization and joint lubrication as structure and signaling molecule; Also playing an important role aspect inflammation and injury repairing, the moisture of keeping skin and the elasticity simultaneously.

Discover that the HA oligonucleotide chain of length-specific is being brought into play important function at aspects such as the unusual reparations of antineoplastic immune.Because hyaluronic acid unique chemical characteristic and physiological function, HA and the oligonucleotide chain that comes from HA are widely used in all many-sides such as ophthalmologic operation, arthritis treatment, antitumor, administering mode, cosmetic industry, only HA in 2008 is as raw material, and the dealing money in the world market is about 1,000,000,000 dollars and the trend that increases is year by year arranged.

Occurring in nature HA extensively exists, as the cell envelope of animal tissues, Mammals cause of disease bacterium and the chlorella of viral PBCV-1 dip-dye etc.Present commercial HA mainly from the pathogenic bacteria of animal tissues's (as cockscomb, umbilical cord, buphthalmos, knuckle synovia) and cultivator and higher mammal (as strep, Streptococci) the middle extraction.For the consideration of aspects such as resource limit, cost problem and safety of medicine, above-mentioned production is ideal style absolutely not, and the method for more economic, safe and lasting production HA is done one's utmost to explore by international community.

Molecular biology and development of biology are for the solution of the problems referred to above provides important means.To HA synthesis mechanism in animal and microorganism, the researchs such as clone of the building-up process indispensable gene of many HA all are the means by metabolic engineering, and reconstruction or transformation route of synthesis are produced HA and established solid basis in the host living beings of safety.

Japanese scholar in 2004 Chai paddy grows youth etc.(Chinese patent application number be 200480022328.8) attempts HA synthesizing in plant tissue by express the HA synthetic gene (Has) that obtains from human and paramecium virus (PBCV-1) in transgenic plant.Widner B etc. (Bill Widner et al., Hyaluronic Acid Production in Bacillus subtilis Appl. Environ. Microbiol. 2005,71 (7): 3747 – 3752) successful expression obtains from gram-positive strep in subtilis HA synthetic gene, the engineering genus bacillus is fermented in common triangular flask and obtains 0.5-0.6g/L HA content.

Yet produce hyaluronic acid in plant, because of the conversion difficulty of plant, growth cycle is subject to seasonal restrictions, and many conservative environmentalists oppose transgenic plant, and there is environmentally safe potential hazard etc. in transgenic plant itself and is subjected to application limitations.For subtilis, because of this bacterium has the generation intracellular toxin, the report of various big ring grease classes and lipopeptide antibiotic, and can cause through fermentation, be used for the separation and purification cost up of field of medicaments HA, serial problems such as productive rate reduction.

Many intestinal bacteria that derive from human intestinal are beneficial bacterias of safeguarding intestinal microbial balance and HUMAN HEALTH.In addition e. coli k12 strain cording clearly genetic background, have numerous genetic transformation systems efficiently and genome operability, and be widely used in the biological product of metabolic engineering field with the production high added value.For being that the host carries out the Stephanopoulos G study group that the hyaluronic reported first of engineered production is a Massachusetts Institute Technology with intestinal bacteria.2008 these study group pass through at expression in escherichia coli Gram-positive strep HA synthetic gene SpHasWith brand-new synthetic, optimized codon and be used for escherichia coli expression SeHasGene, this research obtain the HA output of the highest about 0.2g/L.This project intestinal bacteria are difficult to obtain the industrialization utilization because of the HA synthetic yield is low.

Summary of the invention

The purpose of this invention is to provide a kind of efficient product hyaluronic acid engineering colon bacillus and preparation method thereof, overcome and produce hyaluronic shortage of resources, safety issue and low hyaluronic acid synthetic problem in engineering colon bacillus in the prior art.

The present invention efficiently produces the hyaluronic acid engineering colon bacillus with expressing hyaluronan synthase gene (hyaluronic acid synthase Has) and uridine diphosphoglucose dehydrogenase gene (UDP-glucose Dehydrogenase).

The efficient product hyaluronic acid engineering colon bacillus that contains hyaluronan synthase gene and uridine diphosphoglucose dehydrogenase gene of the present invention is to make up acquisition by the following method:

(1) carrier of construction expression hyaluronan synthase gene Has specifically is that the Has that PCR clones is connected in the colibacillary expression vector (as pQE80l);

(2) carrier of construction expression uridine diphosphoglucose dehydrogenase gene, the uridine diphosphoglucose dehydrogenase gene that PCR is cloned connects in the colibacillary expression vector (as pQE80l);

(3) structure contains hyaluronan synthase gene Has ,With contain the uridine diphosphoglucose dehydrogenase gene, the recombinant vectors of co expression in intestinal bacteria; The uridine diphosphoglucose dehydrogenase gene expression carrier that contains with structure in (2) is the template of PCR, and amplification contains driven element (as T5) and drives KfiThe PCR product that D expresses, and be connected into the expression hyaluronan synthase gene that makes up in (1) HasExpression vector in and obtain to contain hyaluronan synthase gene HasWith the uridine diphosphoglucose dehydrogenase gene, and can be in intestinal bacteria the recombinant vectors of co expression.

(4) hyaluronan synthase gene will be obtained to contain in (3) HasWith the recombinant vectors of uridine diphosphoglucose dehydrogenase gene, transformed into escherichia coli (as the JM109 bacterial strain) obtains the hyaluronic engineering colon bacillus of efficient product through screening.

Product hyaluronic acid engineering colon bacillus of the present invention is pHK/JM109, classification called after colon bacillus ( Escherichia coli), preserving number is CGMCC No.3926, China Committee for Culture Collection of Microorganisms common micro-organisms center (the being called for short CGMCC) preservation on June 17th, 2010 in the BeiJing, China city, preservation address: No. 3, Yard 1, BeiChen xi Road, Chaoyang District, Beijing City.

Efficient product hyaluronic acid engineering colon bacillus (pHK/ of the present invention E.coliJM109) specifically preparation by the following method:

(1) make up the expression vector pQEpmHas contain hyaluronan synthase gene, with the pcr amplification method clone be derived from Pasteurella multocida ( Pasteurella multocidaSubsp. Multocida) in hyaluronan synthase gene ( PAsteurella mUltocida hYaluronic aCid sYnthase PmHas), the design of its pcr amplification clone the primer is as follows:

Upstream primer pmHas P1 is 5'-TA GGATCC ATGAACACATTATCACAAGCAAT-3', (SEQ ID No:3 in the sequence table) contains BamH I site GGATCC and initiator codon ATG;

Downstream primer is PmHasP2 is 5'-TA GAGCTC TTASEQ ID No:4 in the TAGAGTTATACTATTAATAAT-3'(sequence table), contain SacI site GAGCTC and terminator codon TAA;

The masterplate of PCR is the genomic dna of Pasteurella multocida strains A TCC 15742, the amplified production warp BamH I and SacBehind the I double digestion, connect into the identical restriction enzyme site among the commercial carrier pQE80L, insert fragment after DNA order-checking conclusive evidence does not have sudden change, with obtaining carrier called after pQEpmHas, gene is PmHas(SEQ ID No:1 in the sequence table)

(2) make up the expression vector pQEkfiD contain the uridine diphosphoglucose dehydrogenase gene, with the pcr amplification method clone be derived from come from intestinal bacteria ( Escherichia coli, E.coli) bacterial strain k5( E. coliK5) GDPG dehydrogenase gene (K in ₅Capsule gene D, KfiD), the design of primers of amplification is as follows:

Upstream primer KfiD P1:5'-TGG AGATCT ATGSEQ ID No:5 in the TTCGGAACACTAAAAATAACT G-3'(sequence table), contain Bgl II site AGATCT and initiator codon ATG);

Downstream primer KfiD P2:5'-TT CTCGAG TTASEQ ID No:6 in the GTCACATTTAAA CAAATCGCGAC-3'(sequence table), contain XhoI site CTCGAG and terminator codon TAA;

The masterplate of PCR is the genomic dna of intestinal bacteria bacterium k5 strains A TCC 23500, the also product of purifying that successfully increases, warp BglII and XhoBehind the I double digestion, connect into the commercial carrier pQE80L's of Qiagen company BamH I and SalI site, gained carrier after DNA sequencing analysis conclusive evidence is inserted fragment and is not had sudden change, the carrier called after pQEkfiD that obtains, corresponding gene called after KfiD gene (SEQ ID No:2 in the sequence table);

(3) make up co expression hyaluronan synthase gene and the recombinant vectors that contains the uridine diphosphoglucose dehydrogenase gene in the intestinal bacteria:

According to the DNA sequences Design PCR primer of the pQEkfiD carrier that builds, amplification T5 promoters driven KfiThe fragment T5:kfiD that D expresses, concrete primer sequence design is as follows:

Upstream primer T5kfiD P1:5'-TA GAGCTCCCTTTCGTCTTCAC _GSEQ ID No:7 in the TCGAGA-3'(sequence table), this primer contains SacThe I site, GAGCTC, wherein subscript G represents C in the original pQE80L carrier is sported G, to eliminate it XhoThe l site, CTCGAG;

Downstream primer T5kfiD P2:5'-TA CTCGAGSEQ ID No:8 in the TTCTGAGGTCATTACTGGATCT-3'(sequence table), this primer contains XhoI site, CTCGAG;

The masterplate of PCR pQEkfiD carrier, the T5:kfiD amplified production of purifying, at first connect into the pGEM-T-Vector(Promega product, www.promega.com) and transformed into escherichia coli JM109 bacterial strain, obtain intermediate carrier pT-T5KfiD, SEQ ID No:9 in the T5:kfiD(sequence table in this carrier) fragment, after sequencing analysis confirmed that nucleotide sequence does not have sudden change, this inserted T5:kfiD fragment warp SacI and XhoBehind the I double digestion, connect into expression vector pQEpmHas's SacI and SalI site and obtaining PmHasWith KfiThe recombinant vectors pQHK of D gene coexpression in intestinal bacteria;

(4) structure of pHK

Dna sequence dna (GenBank No. Y14439) design primer according to the Gram-negative bacteria host wide spectrum plasmid pBBR122 of German MoBiTec company:

Upstream primer PBBR P1:5'-TTTGGT GTCGACSEQ ID NO:10 in the CTTGCCAGCCCGTGGATATGTGG-3'(sequence table); Contain SalThe I restriction enzyme site, GTCGAC

Downstream primer PBBR P1:5'-TTAGGT GTCGACSEQ ID NO:11 in the TCTGTGATGGCTTCCATGTCGGCAG-3'(sequence table), contain SalThe I restriction enzyme site, GTCGAC);

With comprising its replication site and kalamycin resistance gene among the above-mentioned primer amplification plasmid pBBR122 in interior fragment, the parameter of PCR amplification is: 95 ℃, 2min, 1 circulation; 94 ℃, 30s, 55 ℃, 30s, 72 ℃, 3min, 25 circulations; 72 ℃, 1 circulation of 10min, the about 3.2 kb amplified productions of purifying are used SalBehind the I enzymolysis, add ligase enzyme and connect certainly, self connect product transformed into escherichia coli JM109 bacterial strain, and obtain plasmid pRP (SEQ ID NO:12 in the sequence table), extract plasmid pRP, warp with the kantlex screening by it SalBehind the I enzymolysis, connect into above-mentioned can be in intestinal bacteria coexpression pmHas and KfiThe pQHK's of D gene XhoThe I site, and obtain coexpression in Gram-negative bacteria PmHasWith KfiD synthesizes hyaluronic expression vector pHK;

(5) this recombinant vectors pHK is changed over to the hyaluronic engineering colon bacillus pHK/JM109(CGMCC of the described efficient product of acquisition NO:3926 in the e. coli jm109).

Above-described coli strain pHK/JM109 is the efficient hyaluronic acid engineering colon bacillus that produces, and wherein pHK is the host strain of expression vector for expression vector JM109.

Compared with prior art, the invention has the beneficial effects as follows:

1, engineering colon bacillus of the present invention can produce hyaluronic acid 2g/L～2.5g/L, than in the prior art by expression in escherichia coli Gram-positive strep HA synthetic gene spHas and brand-new synthetic, the hyaluronic acid volume of production of the highest about 0.2g/L that optimized codon and be used for that the seHas gene of escherichia coli expression obtains improves nearly 10 times.

2, the present invention is used in the hyaluronan synthase gene pmHas of derived from gram-negative bacteria for the first time and contains the uridine diphosphoglucose dehydrogenase gene KfiD expresses in the Gram-negative host and produces hyaluronic acid.

3, the constructed recombinant expression vector pHK of the present invention contains the essential fragment that can duplicate of wide spectrum in gram negative bacterium, and drives hyaluronan synthase gene pmHas and contain the uridine diphosphoglucose dehydrogenase gene KfiThe D expression promoter has activity preferably, and makes recombinant expression vector pHK of the present invention in most of gram negative bacterium, can be used for producing hyaluronic acid in (other non-intestinal bacteria) gram negative bacterium.

Description of drawings

Fig. 1 is that hyaluronic acid synthetase catalysis GDPG acid and the polymerization of GDPG amine form hyaluronic procedure chart among the present invention.

Fig. 2 is a coexpression of the present invention PmHaS and KfiDCarrier figure, wherein A:pQHK only is used at expression in escherichia coli; B:pHK both can be used for can also being used for expressing at other Gram-negative bacterias at expression in escherichia coli;

Fig. 3 be the matter acid synthase gene that shows transparency of the present invention ( PmHas) and contain the uridine diphosphoglucose dehydrogenase gene ( KfiD) the expression figure in the e. coli jm109 bacterial strain, pmHAS detection of expression in the A:pQEpmHAS/JM109 bacterial strain wherein, pmHAS and kfiD coexpression detect in the B:pHK/JM109 bacterial strain. A1, B1 is respectively pQEpmHAS/JM109 bacterial strain and pHK/JM109 bacterial strain, electrophoresis through the Ni-NTA-Agrose purifying, show that the pmHas molecular weight is about 110kD, the kfiD molecular weight is about 45kD, A2, B2 is that (molecular weight is respectively 225 150 100 75 50 35 25 15 (KDa) to the molecular weight of albumen standard from top to bottom, A3, B3: the total soluble protein electrophoresis that is respectively pQE80L/JM109 and pBQ/JM109 (empty carrier conversion), A4, B4 are respectively the total soluble protein electrophoresis of pQEpmHas/M109 and pHK/JM109.

Dna sequence dna explanation involved in the present invention

In the sequence table shown in the SEQ ID NO:1 be derived from Pasteurella multocida ( Pasteurella multocidaSubsp. MultocidaIn hyaluronan synthase gene PmHasThe coding region nucleotide sequence.

In the sequence table shown in the SEQ ID NO:2 is to be derived from intestinal bacteria k5 bacterial strain (middle GDPG dehydrogenase gene KfiDThe coding region nucleotide sequence.

In the sequence table shown in the SEQ ID NO:3 be clone be derived from Pasteurella multocida ( Pasteurella multocidaSubsp. Multocida) in hyaluronan synthase gene PmHasThe base sequence of upstream primer.

In the sequence table shown in the SEQ ID NO:4 be clone be derived from Pasteurella multocida ( Pasteurella multocidaSubsp. Multocida) in hyaluronan synthase gene PmHasThe base sequence of downstream primer.

In the sequence table shown in the SEQ ID NO:5 is that the clone comes from GDPG dehydrogenase gene in the intestinal bacteria k5 bacterial strain KfiThe base sequence of the upstream primer of D.

In the sequence table shown in the SEQ ID NO:6 is that the clone comes from GDPG dehydrogenase gene in the intestinal bacteria k5 bacterial strain KfiThe base sequence of the downstream primer of D.

In the sequence table shown in the SEQ ID NO:7 is the base sequence of the segmental upstream primer of clone T5:kfiD.

In the sequence table shown in the SEQ ID NO:8 is the base sequence of the segmental downstream primer of clone T5:kfiD.

In the sequence table shown in the SEQ ID NO:9 is the segmental nucleotide sequence of T5:kfiD.

In the sequence table shown in the SEQ ID NO:10 is clone's PBRR122 kalamycin resistance gene and the base sequence that duplicates essential segmental upstream primer.

In the sequence table shown in the SEQ ID NO:11 is clone's PBRR122 kalamycin resistance gene and the base sequence that duplicates essential segmental downstream primer.

In the sequence table shown in the SEQ ID NO:12 is the nucleotide sequence of plasmid pRP.

The genetic resources that the present invention relates to

1: kill Bath DS strains A TCC15742(Pasteurella multocida subsp. multocida (Lehmann and Neumann) Rosenbusch and Merchant) more; Genetic resources is taken from: U.S.'s typical case's culture is preserved center (ATCC); Obtain manner: buy price 225 U.S. dollars; Acquisition time: in January, 2008; Primary source: U.S. scientist KL Heddleston separates acquisition time from the turkey heart: in April, 1962

2: intestinal bacteria K5 strains A TCC23500( Escherichia coli(Migula) Castellani and Chalmers, serotype O2a, 2b:K5 (L): H4; Genetic resources is taken from: U.S.'s typical case's culture is preserved center (ATCC) obtain manner: buy, price 225 U.S. dollars, acquisition time: in September, 2008 primary source: the Center for Disease Control (CDC) scientist Kauffmann separates from people urine, and acquisition time: July nineteen forty-three.

Embodiment

The present invention is for a more detailed description by following examples, but the present invention is not limited to this.

Embodiment

Be derived from Pasteurella multocida ( Pasteurella multocidaSubsp. Multocida) in hyaluronan synthase gene PmHasThe clone and contain hyaluronan synthase gene PmHasStructure and the transformed into escherichia coli JM109 bacterial strain of expression vector pQEpmHas.Concrete steps are as follows:

(1) make up the expression vector pQEpmHas contain hyaluronan synthase gene, with the pcr amplification method clone be derived from Pasteurella multocida ( Pasteurella multocidaSubsp. Multocida) in hyaluronan synthase gene ( PAsteurella mUltocida hYaluronic aCid synthase PmHas), the design of its pcr amplification clone the primer is as follows:

Upstream primer pmHas P1 is 5'-TA GGATCC ATGAACACATTATCACAAGCAAT-3', (SEQ ID No:3 in the sequence table) contains BamH I site GGATCC and initiator codon ATG;

Downstream primer is PmHasP2 is 5'-TA GAGCTC TTASEQ ID No:4 in the TAGAGTTATACTATTAATAAT-3'(sequence table), contain SacI site GAGCTC and terminator codon TAA;

The masterplate of PCR is the genomic dna of Pasteurella multocida strains A TCC 15742, the amplified production warp BamH I and SacBehind the I double digestion, connect into the identical restriction enzyme site among the commercial carrier pQE80L, insert fragment after DNA order-checking conclusive evidence does not have sudden change, with obtaining carrier called after pQEpmHas, gene is PmHasShown in SEQ ID NO:1 in the sequence table.

In the intestinal bacteria PmHasExpress purifying and determination of activity:

To contain pQEpmHas e. coli jm109 bacterial strain, containing 100ug/L Amp(acillin) LB(agar solid) substratum, 10g/L Tryptone(tryptone), 5g/L Yeast extract(yeast extract), 10g/L NaCl, pH 7.0, and line is producing single bacterium colony on the 15g/L agar plate, and picking list bacterium colony places LB that 5ml contains 100u/L Amp to cultivate and obtained seed liquor in 14-16 hour at 37 ℃, 250 rpm; Seed liquor is grown to the about 0.5-0.6 of culture 600nm photoabsorption by 100 times (V/V) cultivation in the new LB that contains 100u/L Amp; At this moment add the isopropyl-that final concentration is 1mM at once, isopropyl-beta-D-thiogalactoside (IPTG), and 30 ℃ of cultivations 6-8 hour.Culture is collected bacterium through the centrifugal 5min of 12000 rpm, thalline equal-volume 50 mM(pH8.0) after the sodium phosphate buffer washing, recentrifuge is collected, thalline is suspended in pH8.0 with about 0.2g fresh weight/ml concentration, contain 50 mM sodium phosphates, 300mM NaCl, 10mM imidazoles (imidazole), the 1mM N,O-Diacetylmuramidase, after in the mixed solution of the proteinase inhibitor of 2mM (DMSF), (0-4 ℃) ultrasonic disruption is homogenate under the low temperature, and cell lysate is got supernatant liquor and got through centrifugal 20 min of 12000 RPM PmHasCrude extract.This crude extract joins in the chromatography column that contains Ni-NTA-Agrose (Sigma company product), with pH 8.0, contain the 50mM sodium phosphate, 300mM NaCl, 20 mM imidazoles (imidazole) solution washings and with pH 8.0, contain 50 mM sodium phosphates, 300mM NaCl, 250 mM imidazoles (imidazole) eluant solutions are collected elutriant.This elute soln is through 10mM pH7.0 Tris-HCl dialysed overnight, purifying hyaluronic acid synthetase ( PmHas), from the visible hyaluronic acid synthetase of Fig. 3 ( PmHas) in the e. coli jm109 bacterial strain, obtain to efficiently express, and be purified as the single band of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE).

The activation analysis of hyaluronic acid synthetase adopts external hyaluronic accumulation to measure, enzymatic reaction is to carry out in the 50ul system, this system contains 100mM Tris HCl (pH7.0), 40mM MgSO4,0.5mM ethylene glycol diethyl ether tetraacethyl (EGTA), 2mM, mercaptoethanol 0.1% bovine serum albumin, (BSA), 2mM uridine diphosphate (UDP) 6-glucuronic acid (UDP-GlcA) is in 2mM uridine diphosphate (UDP) nitrogen acetylglucosamine (UDP-GlcNAc) dilution different with 10ul, the different purge process and the pmHas enzyme liquid of different steps.After reactant mixes, behind reaction 60min under 37 ℃ of conditions, make the enzyme deactivation termination reaction with 90 ℃ of 5min, centrifugal reaction mixture is got supernatant and is measured hyaluronic acid contents.

Hyaluronic acid contents is measured and is adopted hyaluronic acid binding protein (Hyaluronic Acid Binding Protein, HABP) measure, the present invention adopts hyaluronic acid radioimmunoassay kit (Beijing North biotechnology research institute product, http://www.bnibt.com,) analyze, this assay kit adopts competition radio immunoassay, promptly HA in standard or the testing sample and 125I-HA common with the hyaluronic acid binding protein (HABP) of limiting the quantity of being at war with property association reaction under suitable condition.Part 125I-HA combines with HABP and forms mixture, and another part is unbound state.125I-HA and HABP bonded ratio depend on the content of non-marked HA in standard or the testing sample, and the content of non-marked HA is high more, and the mixture that 125I-HA and HABP form is few more.HA-HABP mixture and HABP antibody and second antibody form crosslinked polymer precipitation gets off, and measures sedimentary radiocounting.Can obtain typical curve and regression equation through after the data processing, find the HA content of sample from typical curve.1 unit of enzyme activity (U) is defined as: catalysis in 1 hour forms 1ug hyaluronan molecule number.Protein content employing Bole (Bio-Rad) company's protein determination kit (www.biorad.com) is a protein standard substance with bovine serum albumin (BSA) also in the enzyme liquid, lives with the ratio that calculates enzyme.Table 1 data show PmHasGene obtains activity expression in intestinal bacteria.

Remarks: data are the mean+/-standard error of 3 mensuration in the table 1

Upstream primer KfiD P1:5'-TGG AGATCT ATGSEQ ID No:5 in the TTCGGAACACTAAAAATAACT G-3'(sequence table), contain Bgl II site AGATCT and initiator codon ATG);

Downstream primer KfiD P2:5'-TT CTCGAG TTASEQ ID No:6 in the GTCACATTTAAA CAAATCGCGAC-3'(sequence table), contain XhoI site CTCGAG and terminator codon TAA;

The masterplate of PCR is the genomic dna of intestinal bacteria k5 strains A TCC 23500, the also product of purifying that successfully increases, warp BglII and XhoBehind the I double digestion, connect into the commercial carrier pQE80L's of Qiagen company BamH I and SalI site, gained carrier after DNA sequencing analysis conclusive evidence is inserted fragment and is not had sudden change, the carrier called after pQEkfiD that obtains, corresponding gene called after KfiThe D gene is shown in SEQ ID No:2 in the sequence table.

In the intestinal bacteria KfiThe D expression of gene, purifying and determination of activity:

KfiThe expression of D, purifying is similar to the expression and purification of above-mentioned hyaluronic acid synthetase, specifically is, will contain the e. coli jm109 bacterial strain of pQE kfiD, grows single bacterium colony containing on 100ug/L acillin (Amp) the LB Agar solid medium.Single bacterium colony places 5ml to contain the LB of 100u/L Amp at 37 ℃, 250 rpm cultivated after 14-16 hour, culture is diluted among the LB by 100 times (V/V), 37 ℃ are cultured to OD600nm photoabsorption (OD 600=0.5-0.6), add the IPTG that final concentration is 1mM at once, cultivated 4 hours for 30 ℃, culture is collected bacterium through centrifugal 5 min of 12000 rpm, after thalline washs with the slow liquid of equal-volume 50 mM sodium phosphates, recentrifuge is collected the back and is suspended in pH8.0 with 0.2g fresh weight/ml, contains 50 mM sodium phosphate 300mM NaCl, 10mM imidazoles (imidazole), the 1mM N,O-Diacetylmuramidase is among the proteinase inhibitor DMSF of 2mM.Bacteria suspension (0-4 ℃) ultrasonic disruption at low temperatures is homogenate.Cell homogenates is got supernatant liquor and is got the kfiD crude extract through centrifugal 20 min of 12000 RMP; This crude extract joins in Ni-NTA-Agrose (the Sigma company product) chromatography column, through 50 mM sodium phosphate buffers (pH 8.0), contain 300mM NaCl, the washing of 20 mM imidazoles (imidazole) and the slow liquid (pH 8.0) of 50 mM sodium phosphates, contain 300mM NaCl, 250 mM imidazoles (imidazole) wash-outs, collect elutriant, this solution in 0-4 ℃ of environment, through 10mM pH7.0 Tris-HCl dialysed overnight, purifying KfID.From Fig. 3 as seen KfiThe D gene obtains to efficiently express and be purified as a SDS-PAGE band in intestinal bacteria.

KfiThe determination of activity of D adopts detection UDP-GlcA to carry out in external generation, specifically be in cumulative volume 50 μ l systems, final concentration contains 100 mM Tris-HCl buffer (pH 8.8), 1 mM UDP-Glc, 2 mM NAD+, 5 mM dithiothreitol (DTT) (Dithiothreitol), the different purification phase of middle adding 2.5-5 μ l, different dilution KfiD enzyme liquid, behind 37 ℃ of reaction 10 min, 100 ℃ of 5min termination reactions.Reaction mixture is got supernatant liquor behind centrifugal 10 min of 13000 rpm, and supernatant liquor is used for the generation that HPLC analyzes UDP-GlcA after the cellulose acetate filter of 0.22 μ l filters.

UDP-GlcA analyzes and carries out in high performance liquid chromatography (HPLC) system (Agilent 1100 series), analytical column is carbon C18 reversed-phase column (Waters Jsphere ODS H80,150 x, 4.6 mm i.d., 4 μ m-particle size). the moving phase of analysis is the filtering solution A of cellulose acetate filter (the 100 mM KH through 0.22 μ l ₂PO4 pH, 5.3 include 8 mM sulfuric acid tetrabutyl ammonia (tetrabutylammonium hydrogen sulfate) and solution B (70% solution A+30% methyl alcohol (pH 5.9).Chromatography condition is: 40 ℃ of column temperatures, 0 min, 100% solution A, 15min 30%A+70% solution B, 20 min, 100% solution B, 30min 100% solution B, 35min 100% solution A, 50min 100% solution A. use the UDP-GlcA(Sigma product) manufacture typical curve for standard specimen and carry out the calculating that enzymatic UDP-GlcA forms.1 unit of enzyme activity (U) is defined as the enzymatic vigor that 1min catalysis forms 1umol UDP-GlcA.(Bio-Rad, www.biorad.com) company's protein determination kit is a protein standard substance with BSA also to protein content employing Bole in the enzyme liquid, lives with the ratio that calculates enzyme.Table 2 data show that KfiD obtains activity expression in intestinal bacteria.

Remarks: data are the mean+/-standard error of 3 mensuration in the table 2

By table 2 data as can be known KfiD obtains activity expression in e. coli jm109.

(3) PmHasWith KfiThe structure of D gene co-expression carrier in intestinal bacteria:

According to T5:kfiDDNA sequence (SEQ ID NO:9 in the sequence table) the design PCR primer of the pQEkfiD carrier that builds, amplification T5Promoters driven KfiThe fragment T5:kfiD that D expresses, concrete primer sequence is:

Upstream primer T5kfiD P1:5'-TA GAGCTCCCTTTCGTCTTCAC _GSEQ ID NO:7 in the TCGAGA-3'(sequence table), this primer contains SacThe I site, GAGCTC, wherein subscript G represents C in the original pQE80L carrier is sported G, to eliminate it XhoThe l site, CTCGAG;

Downstream primer T5kfiD P2:5'-TA CTCGAGSEQ ID NO:8 in the TTCTGAGGTCATTACTGGATCT-3'(sequence table), this primer contains XhoI site, CTCGAG;

It is synthetic that primer is given birth to the worker by Shanghai, the masterplate of PCR pQEkfiD carrier, and the parameter of PCR amplification is: 95 ℃, 2min, 1 circulation, 94 ℃, 30s, 55 ℃, 30s, 72 ℃, 1.5min, 25 circulations, 72 ℃, 10 min, 1 circulation.The about 1.4kb amplified production of purifying, at first connect into commercial carrier pGEM-T-Vector and transformed into escherichia coli JM109 bacterial strain, obtain intermediate carrier pT-T5KfiD, SEQ ID NO:9 in the T5:kfiD(sequence table in this carrier) fragment, after sequencing analysis confirmed that nucleotide sequence does not have sudden change, this inserted T5:kfiD fragment warp SacI and XhoBehind the I double digestion, connect into plasmid pQEpmHas's SacI and SalI site and obtaining PmHasWith KfiThe D gene is co-expression carrier pQHK in intestinal bacteria.

(4) structure of expression vector pHK

For making PmHasWith KfiD can express in comprising other Gram-negative bacterias of intestinal bacteria, according to dna sequence dna (GenBank No. Y14439) the design primer of the Gram-negative bacteria host wide spectrum plasmid pBBR122 of German MoBiTec company:

Upstream primer PBBR P1:5'-TTTGGT GTCGACSEQ ID NO:10 in the CTTGCCAGCCCGTGGATATGTGG-3'(sequence table); Contain SalThe I restriction enzyme site, GTCGAC

Downstream primer PBBR P1:5'-TTAGGT GTCGACSEQ ID NO:11 in the TCTGTGATGGCTTCCATGTCGGCAG-3'(sequence table), contain SalThe I restriction enzyme site, GTCGAC);

Increasing with above-mentioned up and down primer comprises its replication site and kalamycin resistance gene among the plasmid pBBR122 in interior fragment, and the parameter of PCR amplification is: 95 ℃, 2 min, 1 circulation; 94 ℃, 30s, 55 ℃, 30s, 72 ℃, 3 min, 25 circulations; 72 ℃, 1 circulation of 10 min, the about 3.2 kb amplified productions of purifying are used SalBehind the I enzymolysis, add ligase enzyme and connect certainly, self connect product transformed into escherichia coli JM109 bacterial strain, and obtain plasmid pRP (SEQ ID NO:12 in the sequence table) with the kantlex screening by it.In e. coli jm109/pRP, extract plasmid pRP, use SalConnect into pQE80L behind the I enzymolysis, pQEpmHas's XhoBehind the I site, obtain plasmid pBQ and pBQpmHas. respectively and will from pT-T5kfiD, use SacI and XhoThe T5:kfiD that the I double digestion obtains connects into carrier pBQpmHas's SacI and SalThe I site, or will SalThe pRP fragment of I enzymolysis connects into carrier pQHK's XhoI site and obtain in Gram-negative bacteria, can express PmHasWith KfiD sees Fig. 2 with synthetic hyaluronic expression vector pHK().

Wherein: commercial carrier pGEM-T-Vector is the product of buying from Promega company, the website www.promega.com.cn of the said firm, and Promega company provides the sequence of carrier pGEM-T-Vector.Gram-negative bacteria host wide spectrum plasmid pBBR122 buys from German MoBiTec company, and the dna sequence dna of this Gram-negative bacteria host wide spectrum plasmid pBBR122 is Y14439 in the number of obtaining of the GenBank of NCBI.

(5) efficiently produce hyaluronic engineering colon bacillus pHK/JM109(CGMCC NO:3926) acquisition and evaluation

PHK changes in the e. coli jm109 with this recombinant vectors, promptly obtain the hyaluronic engineering colon bacillus pHK/JM109(CGMCC of described efficient product NO:3926), the evaluation of this bacterial strain and checking, the employing following steps are carried out: rule on the LB flat board that contains 50ug/ml kantlex and 100ug/ml acillin, 37 ℃ grow the single bacterium colony of pHK/JM109, and this list colony inoculation is in the LB of identical antibiotic concentration, 37 ℃, 250rpm shaking table incubated overnight obtains kind of a daughter bacteria.To plant daughter bacteria with 100 times of dilutions (V/V), 37 ℃ when being cultured to OD600 and reaching 0.4-0.5, in nutrient solution, add final concentration and reach the IPTG of 1mM and culture temperature is reduced to 30 ℃, cultivate 6 hours to induce the expression of pmHas and kfiD among the pHK.The bacterial cell of having expressed pmHas and kfiD gene among the pHK is used for through the centrifugal collection of 5000rpm 10 min PmHasWith KfiThe Protein Detection of D, enzyme assay and hyaluronic synthetic.Warp PmHasWith KfiThe D enzymic activity detects (method as mentioned above) and confirms among the pHK PmHasWith KfiThe D gene all can be in intestinal bacteria activity expression (table 1, table 2 and Fig. 3).

Above-described coli strain pHK/JM109 is the efficient hyaluronic acid engineering colon bacillus that produces, and its host strain JM109 is commercially available prod commonly used, can from biological chemistry, molecular biology company (as, Sigma, Promega, worker etc. is given birth in Shanghai) buy and obtain.

Pasteurella multocida ( Pasteurella multocida ubsp. Multocida) strains A TCC 15742 is commercial bacterial strain, is that the preserving number of buying from American type culture collection (being called for short ATCC) is 15742;

The design of primers of amplification is with reference to De Angelis PL etc., 1998 (DeAngelis, P.L et al, Identification and Molecular Cloning of a Unique Hyaluronan Synthase from Pasteurella multocida.J.Biol, Chem. 273,8454 – 8458) Bao Dao sequence designs, and this sequence website sequence number of (NCBI) in the American National bioinformation is AF036004.

Commercial carrier pQE80L is from German Qiagen company (www.qiagen.com, order phone: 800-426-8157) buy, and this www.qiagen.com has announced the sequence of carrier pQE80L.

Sequence table

SEQUENCE LISTING

＜110〉Yunnan Province's microbial fermentation engineering research centre company limited

＜120〉efficiently produce the hyaluronic acid engineering colon bacillus

<130> /

<160> 12

<170> PatentIn version 3.3

<210> 1

<211> 2919

<212> DNA

<213> Pasteurella multocida subsp. Multocida(ATCC15742)

<400> 1

atgaatacat tatcacaagc aataaaagca tataacagca atgactatca attagcactc 60

aaattatttg aaaagtcggc ggaaatctat ggacggaaaa ttgttgaatt tcaaattacc 120

aaatgcaaag aaaaactctc agcacatcct tctgttaatt cagcacatct ttctgtaaat 180

aaagaagaaa aagtcaatgt ttgcgatagt ccgttagata ttgcaacaca actgttactt 240

tccaacgtaa aaaaattagt actttctgac tcggaaaaaa acacgttaaa aaataaatgg 300

aaattgctca ctgagaagaa atctgaaaat gcggaggtaa gagcggtcgc ccttgtacca 360

aaagattttc ccaaagatct ggttttagcg cctttacctg atcatgttaa tgattttaca 420

tggtacaaaa agcgaaagaa aagacttggc ataaaacctg aacatcaaca tgttggtctt 480

tctattatcg ttacaacatt caatcgacca gcaattttat cgattacatt agcctgttta 540

gtaaaccaaa aaacacatta cccgtttgaa gttatcgtga cagatgatgg tagtcaggaa 600

gatctatcac cgatcattcg ccaatatgaa aataaattgg atattcgcta cgtcagacaa 660

aaagataacg gttttcaagc cagtgccgct cggaatatgg gattacgctt agcaaaatat 720

gactttattg gcttactcga ctgtgatatg gcgccaaatc cattatgggt tcattcttat 780

gttgcagagc tattagaaga tgatgattta acaatcattg gtccaagaaa atacatcgat 840

acacaacata ttgacccaaa agacttctta aataacgcga gtttgcttga atcattacca 900

gaagtgaaaa ccaataatag tgttgccgca aaaggggaag gaacagtttc tctggattgg 960

cgcttagaac aattcgaaaa aacagaaaat ctccgcttat ccgattcgcc tttccgtttt 1020

tttgcggcgg gtaatgttgc tttcgctaaa aaatggctaa ataaatccgg tttctttgat 1080

gaggaattta atcactgggg tggagaagat gtggaatttg gatatcgctt attccgttac 1140

ggtagtttct ttaaaactat tgatggcatt atggcctacc atcaagagcc accaggtaaa 1200

gaaaatgaaa ccgatcgtga agcgggaaaa aatattacgc tcgatattat gagagaaaag 1260

gtcccttata tctatagaaa acttttacca atagaagatt cgcatatcaa tagagtacct 1320

ttagtttcaa tttatatccc agcttataac tgtgcaaact atattcaacg ttgcgtagat 1380

agtgcactga atcagactgt tgttgatctc gaggtttgta tttgtaacga tggttcaaca 1440

gataatacct tagaagtgat caataagctt tatggtaata atcctagggt acgcatcatg 1500

tctaaaccaa atggcggaat agcctcagca tcaaatgcag ccgtttcttt tgctaaaggt 1560

tattacattg ggcagttaga ttcagatgat tatcttgagc ctgatgcagt tgaactgtgt 1620

ttaaaagaat ttttaaaaga taaaacgcta gcttgtgttt ataccactaa tagaaacgtc 1680

aatccggatg gtagcttaat cgctaatggt tacaattggc cagaattttc acgagaaaaa 1740

ctcacaacgg ctatgattgc tcaccacttt agaatgttca cgattagagc ttggcattta 1800

actgatggat tcaatgaaaa aattgaaaat gccgtagact atgacatgtt cctcaaactc 1860

agtgaagttg gaaaatttaa acatcttaat aaaatctgct ataaccgtgt attacatggt 1920

gataacacat caattaagaa acttggcatt caaaagaaaa accattttgt tgtagtcaat 1980

cagtcattaa atagacaagg cataacttat tataattatg acgaatttga tgatttagat 2040

gaaagtagaa agtatatttt caataaaacc gctgaatatc aagaagagat tgatatctta 2100

aaagatatta aaatcatcca gaataaagat gccaaaatcg cagtcagtat tttttatccc 2160

aatacattaa acggcttagt gaaaaaacta aacaatatta ttgaatataa taaaaatata 2220

ttcgttattg ttctacatgt tgataagaat catcttacac cagatatcaa aaaagaaata 2280

ctagccttct atcataaaca tcaagtgaat attttactaa ataatgatat ctcatattac 2340

acgagtaata gattaataaa aactgaggcg catttaagta atattaataa attaagtcag 2400

ttaaatctaa attgtgaata catcattttt gataatcatg acagcctatt cgttaaaaat 2460

gacagctatg cttatatgaa aaaatatgat gtcggcatga atttctcagc attaacacat 2520

gattggatcg agaaaatcaa tgcgcatcca ccatttaaaa agctcattaa aacttatttt 2580

aatgacaatg acttaaaaag tatgaatgtg aaaggggcat cacaaggtat gtttatgacg 2640

tatgcgctag cgcatgagct tctgacgatt attaaagaag tcatcacatc ttgccagtca 2700

attgatagtg tgccagaata taacactgag gatatttggt tccaatttgc acttttaatc 2760

ttagaaaaga aaaccggcca tgtatttaat aaaacatcga ccctgactta tatgccttgg 2820

gaacgaaaat tacaatggac aaatgaacaa attgaaagtg caaaaagagg agaaaatata 2880

cctgttaaca agttcattat taatagtata actctataa 2919

<210> 2

<211> 1179

<212> DNA

<213> Escherichia coli K5(ATCC23500)

<400> 2

atgttcggaa cactaaaaat aactgtttca ggcgctggtt acgttgggct ttcaaatgga 60

attctaatgg ctcaaaatca tgaagtggtt gcatttgata cccatcaaaa aaaagttgac 120

ttacttaatg ataaactctc tcctatagag gataaggaaa ttgaaaatta tctttcaact 180

aaaatactta attttcgcgc aactactaac aaatatgaag cctataaaaa tgccaattac 240

gttattattg ctacaccaac gaattatgac ccaggttcaa attactttga tacatcaagc 300

gttgaagctg tcattcgtga cgtaacggaa atcaacccaa acgcaattat ggtggttaaa 360

tctacggtcc cagtaggttt cacaaaaaca attaaagaac atttaggtat taataatatt 420

atcttctctc cagaattttt acgagaagga agagccctat acgataatct ccatccatct 480

cgcattatta tcggtgaatg ttctgaacgg gcagaacgtt tggcagtgtt atttcaggaa 540

ggagcgatta aacaaaatat acccgtttta tttacagatt ctacggaagc ggaagcgatt 600

aagttatttt caaatactta tttggctatg cgagttgcat tttttaatga attggatagt 660

tacgcagaaa gttttggtct gaatacgcgt cagattattg acggtgtttg tttggatccg 720

cgcattggta attactacaa taatccttct tttggttatg gtggctactg tttgccaaaa 780

gataccaagc aattattagc caactatcag tctgttccga ataaacttat atctgcaatt 840

gttgatgcta accgtacacg taaggacttt atcactaatg ttattttgaa acatagacca 900

caagttgtgg gggtttatcg tttgattatg aaaagtggtt cagataattt tagagattct 960

tctattcttg gtattataaa gcgtatcaag aaaaaaggcg tgaaagtaat tatttatgag 1020

ccgcttattt ctggagatac attctttaac tcacctttgg aacgggagct ggcgatcttt 1080

aaagggaaag ctgatattat tatcactaac cgaatgtcag aggagttgaa cgatgtggtc 1140

gacaaagtct atagtcgcga tttgtttaaa tgtgactaa 1179

<210> 3

<211> 31

<212> DNA

＜213〉artificial-synthetic DNA

<400> 3

taggatccat gaacacatta tcacaagcaa t 31

<210> 4

<211> 32

<212> DNA

＜213〉artificial-synthetic DNA

<400> 4

tagagctctt atagagttat actattaata at 32

<210> 5

<211> 34

<212> DNA

＜213〉artificial-synthetic DNA

<400> 5

tggagatcta tgttcggaac actaaaaata actg 34

<210> 6

<211> 34

<212> DNA

＜213〉artificial-synthetic DNA

<400> 6

ttctcgagtt agtcacattt aaacaaatcg cgac 34

<210> 7

<211> 29

<212> DNA

＜213〉artificial-synthetic DNA

<400> 7

tagagctccc tttcgtcttc acgtcgaga 29

<210> 8

<211> 30

<212> DNA

＜213〉artificial-synthetic DNA

<400> 8

tactcgagtt ctgaggtcat tactggatct 30

<210> 9

<211> 1423

<212> DNA

＜213〉engineering makes up fragment

<400> 9

tagagctccc tttcgtcttc acgtcgagaa atcataaaaa atttatttgc tttgtgagcg 60

gataacaatt ataatagatt caattgtgag cggataacaa tttcacacag aattcattaa 120

agaggagaaa ttaactatga gaggatcgca tcaccatcac catcacggat ctatgttcgg 180

aacactaaaa ataactgttt caggcgctgg ttacgttggg ctttcaaatg gaattctaat 240

ggctcaaaat catgaagtgg ttgcatttga tacccatcaa aaaaaagttg acttacttaa 300

tgataaactc tctcctatag aggataagga aattgaaaat tatctttcaa ctaaaatact 360

taattttcgc gcaactacta acaaatatga agcctataaa aatgccaatt acgttattat 420

tgctacacca acgaattatg acccaggttc aaattacttt gatacatcaa gcgttgaagc 480

tgtcattcgt gacgtaacgg aaatcaaccc aaacgcaatt atggtggtta aatctacggt 540

cccagtaggt ttcacaaaaa caattaaaga acatttaggt attaataata ttatcttctc 600

tccagaattt ttacgagaag gaagagccct atacgataat ctccatccat ctcgcattat 660

tatcggtgaa tgttctgaac gggcagaacg tttggcagtg ttatttcagg aaggagcgat 720

taaacaaaat atacccgttt tatttacaga ttctacggaa gcggaagcga ttaagttatt 780

ttcaaatact tatttggcta tgcgagttgc attttttaat gaattggata gttacgcaga 840

aagttttggt ctgaatacgc gtcagattat tgacggtgtt tgtttggatc cgcgcattgg 900

taattactac aataatcctt cttttggtta tggtggctac tgtttgccaa aagataccaa 960

gcaattatta gccaactatc agtctgttcc gaataaactt atatctgcaa ttgttgatgc 1020

taaccgtaca cgtaaggact ttatcactaa tgttattttg aaacatagac cacaagttgt 1080

gggggtttat cgtttgatta tgaaaagtgg ttcagataat tttagagatt cttctattct 1140

tggtattata aagcgtatca agaaaaaagg cgtgaaagta attatttatg agccgcttat 1200

ttctggagat acattcttta actcaccttt ggaacgggag ctggcgatct ttaaagggaa 1260

agctgatatt attatcacta accgaatgtc agaggagttg aacgatgtgg tcgacaaagt 1320

ctatagtcgc gatttgttta aatgtgacta actcgaccca agcttaatta gctgagcttg 1380

gactcctgtt gatagatcca gtaatgacct cagaactcga gta 1423

<210> 10

<211> 33

<212> DNA

＜213〉artificial-synthetic DNA

<400> 10

tggtgtcgac cttgccagcc cgtggatatg tgg 33

<210> 11

<211> 35

<212> DNA

＜213〉artificial-synthetic DNA

<400> 11

aggtgtcgac tctgtgatgg cttccatgtc ggcag 35

<210> 12

<211> 3266

<212> DNA

<213> pBBR122

<400> 12

gtcgaccttg ccagcccgtg gatatgtgga cgatggccgc gagcggccac cggctggctc 60

gcttcgctcg gcccgtggac aaccctgctg gacaagctga tggacaggct gcgcctgccc 120

acgagcttga ccacagggat tgcccaccgg ctacccagcc ttcgaccaca tacccaccgg 180

ctccaactgc gcggcctgcg gccttgcccc atcaattttt ttaattttct ctggggaaaa 240

gcctccggcc tgcggcctgc gcgcttcgct tgccggttgg acaccaagtg gaaggcgggt 300

caaggctcgc gcagcgaccg cgcagcggct tggccttgac gcgcctggaa cgacccaagc 360

ctatgcgagt gggggcagtc gaaggcgaag cccgcccgcc tgccccccga gacctgcagg 420

gggggggggg cgctgaggtc tgcctcgtga agaaggtgtt gctgactcat accaggcctg 480

aatcgcccca tcatccagcc agaaagtgag ggagccacgg ttgatgagag ctttgttgta 540

ggtggaccag ttggtgattt tgaacttttg ctttgccacg gaacggtctg cgttgtcggg 600

aagatgcgtg atctgatcct tcaactcagc aaaagttcga tttattcaac aaagccgccg 660

tcccgtcaag tcagcgtaat gctctgccag tgttacaacc aattaaccaa ttctgattag 720

aaaaactcat cgagcatcaa atgaaactgc aatttattca tatcaggatt atcaatacca 780

tatttttgaa aaagccgttt ctgtaatgaa ggagaaaact caccgaggca gttccatagg 840

atggcaagat cctggtatcg gtctgcgatt ccgactcgtc caacatcaat acaacctatt 900

aatttcccct cgtcaaaaat aaggttatca agtgagaaat caccatgagt gacgactgaa 960

tccggtgaga atggcaaaag cttatgcatt tctttccaga cttgttcaac aggccagcca 1020

ttacgctcgt catcaaaatc actcgcatca accaaaccgt tattcattcg tgattgcgcc 1080

tgagcgagac gaaatacgcg atcgctgtta aaaggacaat tacaaacagg aatcgaatgc 1140

aaccggcgca ggaacactgc cagcgcatca acaatatttt cacctgaatc aggatattct 1200

tctaatacct ggaatgctgt tttcccgggg atcgcagtgg tgagtaacca tgcatcatca 1260

ggagtacgga taaaatgctt gatggtcgga agaggcataa attccgtcag ccagtttagt 1320

ctgaccatct catctgtaac atcattggca acgctacctt tgccatgttt cagaaacaac 1380

tctggcgcat cgggcttccc atacaatcga tagattgtcg cacctgattg cccgacatta 1440

tcgcgagccc atttataccc atataaatca gcatccatgt tggaatttaa tcgcggcctc 1500

gagcaagacg tttcccgttg aatatggctc ataacacccc ttgtattact gtttatgtaa 1560

gcagacagtt ttattgttca tgatgatata tttttatctt gtgcaatgta acatcagaga 1620

ttttgagaca caacgtggct ttcccccccc cccctgcagg tcccgagcct cacggcggcg 1680

agtgcggggg ttccaagggg gcagcgccac cttgggcaag gccgaaggcc gcgcagtcga 1740

tcaacaagcc ccggaggggc cactttttgc cggaggggga gccgcgccga aggcgtgggg 1800

gaaccccgca ggggtgccct tctttgggca ccaaagaact agatataggg cgaaatgcga 1860

aagacttaaa aatcaacaac ttaaaaaagg ggggtacgca acagctcatt gcggcacccc 1920

ccgcaatagc tcattgcgta ggttaaagaa aatctgtaat tgactgccac ttttacgcaa 1980

cgcataattg ttgtcgcgct gccgaaaagt tgcagctgat tgcgcatggt gccgcaaccg 2040

tgcggcaccc taccgcatgg agataagcat ggccacgcag tccagagaaa tcggcattca 2100

agccaagaac aagcccggtc actgggtgca aacggaacgc aaagcgcatg aggcgtgggc 2160

cgggcttatt gcgaggaaac ccacggcggc aatgctgctg catcacctcg tggcgcagat 2220

gggccaccag aacgccgtgg tggtcagcca gaagacactt tccaagctca tcggacgttc 2280

tttgcggacg gtccaatacg cagtcaagga cttggtggcc gagcgctgga tctccgtcgt 2340

gaagctcaac ggccccggca ccgtgtcggc ctacgtggtc aatgaccgcg tggcgtgggg 2400

ccagccccgc gaccagttgc gcctgtcggt gttcagtgcc gccgtggtgg ttgatcacga 2460

cgaccaggac gaatcgctgt tggggcatgg cgacctgcgc cgcatcccga ccctgtatcc 2520

gggcgagcag caactaccga ccggccccgg cgaggagccg cccagccagc ccggcattcc 2580

gggcatggaa ccagacctgc cagccttgac cgaaacggag gaatgggaac ggcgcgggca 2640

gcagcgcctg ccgatgcccg atgagccgtg ttttctggac gatggcgagc cgttggagcc 2700

gccgacacgg gtcacgctgc cgcgccggta gcacttgggt tgcgcagcaa cccgtaagtg 2760

cgctgttcca gactatcggc tgtagccgcc tcgccgccct ataccttgtc tgcctccccg 2820

cgttgcgtcg cggtgcatgg agccgggcca cctcgacctg aatggaagcc ggcggcacct 2880

cgctaacgga ttcaccgttt ttatcaggct ctgggaggca gaataaatga tcatatcgtc 2940

aattattacc tccacgggga gagcctgagc aaactggcct caggcatttg agaagcacac 3000

ggtcacactg cttccggtag tcaataaacc ggtaaaccag caatagacat aagcggctat 3060

ttaacgaccc tgccctgaac cgacgaccgg gtcgaatttg ctttcgaatt tctgccattc 3120

atccgcttat tatacttatt caggcgtagc accaggcgtt taagggcacc aataactgcc 3180

ttaaaaaaat tacgccccgc cctgccactc atcgcagtac tgttgtaatt cattaagcat 3240

tctgccgaca tggaagccat cacaga 3266

Claims (2)

1. efficient hyaluronic acid engineering colon bacillus that produces, it is characterized in that its classification called after colon bacillus ( Escherichia coli), preserving number is CGMCC No.3926.

2. the preparation method of the described efficient product hyaluronic acid engineering colon bacillus of claim 1 is characterized in that carrying out according to the following steps:

(1) make up the expression vector pQEpmHas contain hyaluronan synthase gene, with the pcr amplification method clone be derived from Pasteurella multocida ( Pasteurella multocidaSubsp. Multocida) in hyaluronan synthase gene ( PAsteurella mUltocida hYaluronic aCid synthase PmHas), the design of its pcr amplification clone the primer is as follows:

Upstream primer pmHas P1 is 5'-TA GGATCC ATGSEQ ID No:3 in the AACACATTATCACAAGCAAT-3'(sequence table), contain BamH I site GGATCC and initiator codon ATG;

Downstream primer is PmHasP2 is 5'-TA GAGCTC TTASEQ ID No:4 in the TAGAGTTATACTATTAATAAT-3'(sequence table), contain SacI site GAGCTC and terminator codon TAA;

The masterplate of PCR is the genomic dna of Pasteurella multocida strains A TCC 15742, the amplified production warp BamH I and SacBehind the I double digestion, connect into the identical restriction enzyme site among the commercial carrier pQE80L, insert fragment after DNA order-checking conclusive evidence does not have sudden change, with obtaining carrier called after pQEpmHas, gene is PmHas(SEQ ID No:1 in the sequence table);

(2) make up the expression vector pQEkfiD contain the uridine diphosphoglucose dehydrogenase gene, with the pcr amplification method clone be derived from come from intestinal bacteria ( Escherichia coli, E.coli) GDPG dehydrogenase gene (K among the bacterial strain k5 ₅Capsule gene D, KfiD), the design of primers of amplification is as follows:

Upstream primer KfiD P1:5'-TGG AGATCT ATGSEQ ID No:5 in the TTCGGAACACTAAAAATAACT G-3'(sequence table), contain Bgl II site AGATCT and initiator codon ATG);

Downstream primer KfiD P2:5'-TT CTCGAG TTASEQ ID No:6 in the GTCACATTTAAA CAAATCGCGAC-3'(sequence table), contain XhoI site CTCGAG and terminator codon TAA;

The masterplate of PCR is the genomic dna of intestinal bacteria bacterium k5 strains A TCC 23500, the also product of purifying that successfully increases, warp BglII and XhoBehind the I double digestion, connect into the commercial carrier pQE80L's of Qiagen company BamH I and SalI site, gained carrier after DNA sequencing analysis conclusive evidence is inserted fragment and is not had sudden change, the carrier called after pQEkfiD that obtains, corresponding gene called after KfiD gene (SEQ ID No:2 in the sequence table);

(3) make up co expression hyaluronan synthase gene and the recombinant vectors that contains the uridine diphosphoglucose dehydrogenase gene in the intestinal bacteria:

According to the DNA sequences Design PCR primer of the pQEkfiD carrier that builds, amplification T5 promoters driven KfiThe fragment T5:kfiD that D expresses, the primer sequence design is as follows:

Upstream primer T5kfiD P1:5'-TA GAGCTCCCTTTCGTCTTCAC _GSEQ ID No:7 in the TCGAGA-3'(sequence table), this primer contains SacThe I site, GAGCTC, wherein subscript G represents C in the original pQE80L carrier is sported G, to eliminate it XhoThe l site, CTCGAG;

Downstream primer T5kfiD P2:5'-TA CTCGAGSEQ ID No:8 in the TTCTGAGGTCATTACTGGATCT-3'(sequence table), this primer contains XhoI site, CTCGAG;

The masterplate of PCR pQEkfiD carrier, the T5:kfiD amplified production of purifying, at first connect into pGEM-T-Vector and transformed into escherichia coli JM109 bacterial strain, obtain intermediate carrier pT-T5KfiD, SEQ ID No:9 in the T5:kfiD(sequence table in this carrier) fragment, after sequencing analysis confirmed that nucleotide sequence does not have sudden change, this inserted pT-T5KfiD fragment warp SacI and XhoBehind the I double digestion, connect into expression vector pQEpmHas's SacI and SalI site and obtaining PmHasWith KfiThe recombinant vectors pQHK of D gene coexpression in intestinal bacteria;

(4) structure of expression vector pHK

Dna sequence dna (GenBank No. Y14439) design primer with the Gram-negative bacteria host wide spectrum plasmid pBBR122 of German MoBiTec company:

Upstream primer PBBR P1:5'-TTTGGT GTCGACSEQ ID NO:10 in the CTTGCCAGCCCGTGGATATGTGG-3'(sequence table); Contain SalThe I restriction enzyme site, GTCGAC;

Downstream primer PBBR P1:5'-TTAGGT GTCGACSEQ ID NO:11 in the TCTGTGATGGCTTCCATGTCGGCAG-3'(sequence table), contain SalThe I restriction enzyme site, GTCGAC;

With comprising its replication site and kalamycin resistance gene among the above-mentioned primer amplification plasmid pBBR122 in interior fragment, the parameter of PCR amplification is: 95 ℃, 2 min, 1 circulation; 94 ℃, 30s, 55 ℃, 30s, 72 ℃, 3 min, 25 circulations; 72 ℃, 1 circulation of 10 min, purifying 3.2 kb amplified productions are used SalBehind the I enzymolysis, add ligase enzyme and connect certainly, self connect product transformed into escherichia coli JM109 bacterial strain by it, and obtain plasmid pRP (SEQ ID NO:12 in the sequence table) with kantlex screening, extract plasmid pRP, behind the SalI enzymolysis, connect into above-mentioned can be in intestinal bacteria coexpression pmHas and KfiThe pQHK's of D gene XhoThe I site obtains coexpression in Gram-negative bacteria PmHasWith KfiD synthesizes hyaluronic expression vector pHK;

(5) this recombinant vectors pHK is changed over to the hyaluronic engineering colon bacillus pHK/JM109 of the described efficient product of acquisition CGMCC NO:3926 in the e. coli jm109.

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