CN103667334B - Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA and preparation method and application - Google Patents
Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA and preparation method and application Download PDFInfo
- Publication number
- CN103667334B CN103667334B CN201310542901.9A CN201310542901A CN103667334B CN 103667334 B CN103667334 B CN 103667334B CN 201310542901 A CN201310542901 A CN 201310542901A CN 103667334 B CN103667334 B CN 103667334B
- Authority
- CN
- China
- Prior art keywords
- znua
- bacterial strain
- brucella melitensis
- recombinant bacterial
- preparation
- 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.)
- Active
Links
Landscapes
- Micro-Organisms Or Cultivation Processes Thereof (AREA)
- Medicines Containing Antibodies Or Antigens For Use As Internal Diagnostic Agents (AREA)
Abstract
The present invention discloses a strain Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA and preparation method and application.The present invention is with Brucella melitensis M5 genome for template, and PCR obtains the upstream and downstream homology arm of znuA gene, and connects, and obtains fragment Δ znuA; Fragment Δ znuA is cloned on carrier pRE112, obtains recombinant plasmid pRE-Δ znuA; Imported by this plasmid in Brucella melitensis M5-Δ bp26 cell, respectively by paraxin and the screening of sucrose Selective agar medium, obtaining homologous recombination double exchange, is recombinant bacterial strain M5-Δ bp26-Δ znuA.This bacterial strain is M5 parent strain comparatively, and growth characteristics are consistent, and inheritance stability makes its not easily reversion, and virulence is little and immune effect keeps good, and detects natural infection or artificial immunization because bp26 genetically deficient mark can be applicable to distinguish.Therefore, this bacterial strain can be used as the better marker vaccine of a kind of effect and is applied to clinical.
Description
Technical field
The invention belongs to recombinant bacteria vaccines arts, particularly strain Brucella melitensis (Brucellamelitensis) recombinant bacterial strain M5-Δ bp26-Δ znuA and preparation method and application.This bacterial strain on the basis that sheep type No. 5 less-virulent strains (M5) lack its bp26 gene, lacks znuA gene obtain.
Background technology
Brucellosis is the Arbo infectious disease being feature with miscarriage and heating caused by brucella, and due to the entozoic feature of Bacillus brucellae born of the same parents, this disease of prevention and control is put prevention first with attenuated vaccine immunity always.Attenuated strain at present for gibraltar fever prevention and control mainly contains external ox type No. 19 (S19) less-virulent strains and sheep type ReV.1 less-virulent strain, sheep type No. 5 (M5) less-virulent strains of domestic development and pig type No. 2 (S2) less-virulent strains.The attenuated vaccine strain of these classics serves vital role in the spreading and spread of prevention and corntrol gibraltar fever.Though Attenuate vaccine low cost, the immunoprotection time length is long, and immunoprotection efficiency is high, and same existing defects, causing people dare not, be reluctant can not to its widespread use.Its major cause one is that Attenuate vaccine cannot distinguish natural infection and artificial immunization after inoculation, widespread use by this sick epidemiology survey, detect epidemic disease source and Disease epizootic and treatment produces very large obstacle; Two is that Attenuate vaccine toxicity is relatively large, and atavism is serious, can damage, even fall ill to man and animal body.So development one can distinguish natural infection or artificial immunization clinically, immune protection performance is good, and the brucellosis attenuated vaccine that virulence is weak, safety performance is high has important practice significance.
In addition, brucellar existence and breed the multiple transition metal ion that must depend among environment or host.Especially zine ion is the necessary metal ion of brucella structure, is the cofactor of catalyzed reaction in thalline, and therefore, the zinc obtaining suitable degree is concerning extremely important bacterium.But because zinc ion content free in host is considerably less, the metabolism of bacterium self is ensured in order to absorb enough zinc, and breed in a large number in host, various bacterium as brucella evolve out several types albumen participate in picked-up and transhipment zine ion, the albumen maneuvering system of these transhipment zine ions is named as ZnuABC, this system comprises znuA, znuB, the multiple protein of znuC genes encoding, wherein ZnuA is a kind of periplasmic-solute binding proteins, still less to the study mechanism of this gene at present, only infer that this ZnuA albumen is relevant to Bacillus brucellae virulence factor.Secondly, BP26 albumen is that one has strong immunogenic periplasm protein, and be almost present in all Bacillus brucellae bacterial strains, this albumen has good immunocompetence, the specific antibody for this antigen can be detected after natural infection or artificial immunization in serum, be therefore commonly used to the target protein as serologic test.
Virulence can be lowered for obtaining a strain, improve security, the efficient immunogenicity of vaccine can be maintained again, and the brucellosis attenuated vaccine distinguishing checkout and diagnosis can be carried out in clinical application, the gene of expressing BP26 and ZnuA albumen knocks out by respectively, to obtain strain Brucella melitensis (Brucellamelitensis) recombinant bacterial strain M5-Δ bp26-Δ znuA and preparation method and application, lay the foundation for preparing safer effective novel gene engineered vaccine, for the synergy studying Bacillus brucellae outer membrane protein BP26 and metal-ions transportation albumen ZnuABC further provides reference.
Summary of the invention
In order to overcome the shortcoming of above-mentioned existing vaccine with not enough, primary and foremost purpose of the present invention is the preparation method providing a strain Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA.
Another object of the present invention is to provide the Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ obtained by above-mentioned preparation method znuA.
Still a further object of the present invention is to provide above-mentioned Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA for the preparation of the application prevented and/or treated in the vaccine of brucellosis.
Object of the present invention is realized by following proposal:
The preparation method of one strain Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA, comprises the following steps:
(1) structure of Suicide homologous recombination plasmid
1. be that template carries out PCR with Brucella melitensis (Brucellamelitensis) M5 genomic dna, when the primer of use is for P1 and P2, obtain the upstream homology arm of znuA gene; When the primer used is for P3 and P4, obtain the downstream homology arm of znuA gene;
P1:5 '-GAT
gGTACCcGTCCTCGTTTGCTTGTGC-3 ' (horizontal line part is KpnI restriction enzyme site);
P2:5′-TCGCTGAAAGACTGCCTGT-3′;
P3:5′-GCAGTCTTTCAGCGAAGCCAGAAAGGCAGAAGC-3′;
P4:5 '-AGA
gAGCTCcAATGTCCCCTTGGTCCC-3 ' (horizontal line part is Sac1 restriction enzyme site);
2. utilize the method for OverlapPCR, with step, 1. the upstream homology arm of the znuA gene of middle preparation and the downstream homology arm of znuA gene are for template, P1 and P4 is primer pair, obtains the object fragment Δ znuA for homologous recombination;
3. double digestion is carried out, purifying to suicide plasmid carrier pRE112 with for the object fragment Δ znuA of homologous recombination respectively with KpnI and SacI; The fragment Δ znuA that purifying reclaims is connected with carrier segments pRE112, obtains Suicide homologous recombination plasmid pRE-Δ znuA;
(2) structure of Brucella melitensis recombinant bacterial strain and screening
1. Suicide homologous recombination plasmid pRE-Δ znuA is imported in the competent cell of Brucella melitensis M5-Δ bp26; Then coat on Triptic soya yeast extract agar substratum (TSA-YE) flat board containing paraxin, under the selective pressure of paraxin, obtain homologous recombination list recon; PCR is identified correct homologous recombination list recon is cultivated in Triptic soya yeast extract broth culture (TSB-YE), lax plasmid resistance;
2. then the homologous recombination list recon after lax plasmid resistance is coated on TSA-YE-Sucrose Selective agar medium and cultivate, utilize the susceptibility of sacB gene pairs sucrose in Suicide homologous recombination plasmid pRE-Δ znuA, suicide plasmid is eliminated, primer P1 and P4 is utilized to carry out PCR screening to the bacterium colony that TSA-YE-Sucrose Selective agar medium grows, obtain homologous recombination double exchange, namely obtain Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA;
Step (1) 1. described in the condition optimization of PCR be 94 DEG C of 2min denaturations; 98 DEG C of 10s, 56 DEG C of 30s, 68 DEG C of 1.5min, 30 circulations; 68 DEG C of 5 ~ 10min extend eventually;
Step (1) 2. described in the condition optimization of OverlapPCR be 94 DEG C of 2min denaturations; 98 DEG C of 10s, 56 DEG C of 30s, 68 DEG C of 3min, 30 circulations; 68 DEG C of 5 ~ 10min extend eventually;
Step (2) 1. described in the mode of importing import preferably by electric transform mode;
The condition optimization that described electricity transforms is 1mm pole cup, 1.8kv, 400 Ω;
Step (2) 1. described in the final concentration of paraxin in described Triptic soya yeast extract agar substratum be preferably 5 μ g/mL;
Step (2) 1. described in the condition optimization of cultivation be 37 DEG C, 18h cultivated by 200r/min shaking table;
Step (2) 1. described in PCR be accredited as and identified by primer P1 and P4;
Step (2) 1. described in PCR qualification condition optimization as follows: 94 DEG C of 2min denaturations; 98 DEG C of 10s, 56 DEG C of 30s, 68 DEG C of 3min, 30 circulations; 68 DEG C of 5 ~ 10min;
Step (2) 2. described in TSA-YE-Sucrose Selective agar medium composed as follows: Triptic soya yeast extract agar substratum (TSA-YE)+final concentration is the sucrose of mass volume ratio (g/mL) 7%;
Described TSA-YE-Sucrose Selective agar medium prepares preferably by following steps: by after Triptic soya yeast extract agar substratum (TSA-YE) sterilizing for preparing, the sucrose that concentration degerming is after filtration mass volume ratio (g/mL) 50% is added when being cooled to 60 ~ 70 DEG C, the final concentration of sucrose is made to be mass volume ratio (g/mL) 7%, be distributed into after mixing in sterilizing plate, solidify rear 4 DEG C of preservations.
Step (2) 2. described in the condition optimization of cultivation be 37 DEG C and cultivate 48 ~ 96h;
One strain Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA, is obtained by above-mentioned preparation method.
Above-mentioned Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA is for the preparation of the application prevented and/or treated in the vaccine of brucellosis.
The present invention, relative to prior art, has following advantage and beneficial effect:
(1) Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA provided by the invention can be used for clinical as a kind of marker vaccine strain due to the disappearance of bp26 gene, thus effective distinguishes natural infection and artificial immunization.Disappearance due to znuA gene makes this strain comparatively parent plant M5 virulence reduction, security improves; Inheritance stability is reversion not easily; Meanwhile, good immunogenicity can also be kept.
(2) Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA provided by the invention this couple of deletion of vaccine strain more single gene-deleted strain M5-Δ bp26 and M5-Δ znuA also all has obvious virulence attenuation of, security high, keeps good immunogenic advantage.
(3) experiment proves that Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA provided by the invention has good genetic stability, its growth characteristics and immune protective effect no significant difference compared with Brucella melitensis M5.
(4) Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA provided by the invention lays the foundation, for the synergy studying Bacillus brucellae outer membrane protein BP26 and metal-ions transportation albumen ZnuA further provides reference for preparing safer effective novel gene engineered vaccine.
Accompanying drawing explanation
Fig. 1 is the agarose gel electrophoresis figure of the gene fragment Δ znuA that the upstream and downstream homology arm gene fragment of znuA gene and upstream and downstream homology arm gene fragment OverlapPCR thereof obtain, wherein: swimming lane M is DNA molecular quality standard, swimming lane 1 is the upstream homology arm gene fragment of znuA, swimming lane 2 is the downstream homology arm gene fragment of znuA, and swimming lane 3 is that the upstream and downstream homology arm gene fragment of znuA gene is connected the gene fragment Δ znuA obtained.
Fig. 2 is the agarose gel electrophoresis figure of pRE-Δ znuA digestion verification result, wherein: swimming lane M is DNA molecular quality standard, swimming lane 1 is the pRE-Δ znuA plasmid cut without enzyme, and swimming lane 2 is the fragment obtained after using KpnI and SacI double digestion pRE-Δ znuA plasmid.
Fig. 3 is the agarose gel electrophoresis figure of Brucella melitensis gene-deleted strain M5-Δ bp26-Δ znuA homologous recombination list recon screening, wherein: swimming lane M is DNA molecular quality standard, swimming lane 1 is pRE-Δ znuA positive control, swimming lane 2 is M5 positive control, and swimming lane 3 ~ 8 is M5-Δ bp26-Δ znuA strain homologous recombination list recon; Swimming lane 9 is blank.
Fig. 4 is the agarose gel electrophoresis figure of Brucella melitensis gene-deleted strain M5-Δ bp26-Δ znuA homologous recombination double exchange screening, wherein: swimming lane M is DNA molecular quality standard, swimming lane 1 is pRE-Δ znuA positive control, swimming lane 2 is M5 positive control, swimming lane 3 ~ 20 is homologous recombination double exchange, and swimming lane 21 is blank.
Fig. 5 is the result figure of Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA genetic stability, wherein: swimming lane M is DNA molecular quality standard, swimming lane 1 is pRE-Δ znuA positive control, swimming lane 2 is M5 positive control, swimming lane 3 ~ 12 is respectively M5-Δ bp26-Δ znuA the 2nd, 4,6,8,10,12,14,16,18,20 generation bacterium colony, and swimming lane 13 is blank.
Fig. 6 is the measurement result figure of Brucella melitensis parent plant M5 and recombinant bacterial strain M5-Δ bp26-Δ znuA growth curve.
Fig. 7 is the result figure affected mouse spleen weight after Brucella melitensis parent plant M5, recombinant bacterial strain M5-Δ bp26, M5-Δ znuA and M5-Δ bp26-Δ znuA distinguish immune mouse.
Fig. 8 is the result figure detected mouse spleen bacterium quantity after Brucella melitensis parent plant M5, recombinant bacterial strain M5-Δ bp26, M5-Δ znuA and M5-Δ bp26-Δ znuA distinguish immune mouse.
Fig. 9 is the ELISA detected result figure of mice serum specific antibody after Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA immune mouse.
Figure 10 is the indirect ELISA detected result figure of Brucella melitensis parent plant M5, recombinant bacterial strain M5-Δ bp26, M5-Δ znuA and M5-Δ bp26-Δ znuA immune mouse mice serum specific antibody after 6 weeks.
Embodiment
Below in conjunction with embodiment and accompanying drawing, the present invention is described in further detail, but embodiments of the present invention are not limited thereto.
Material involved in embodiment:
1. KODFXDNAPolymerase high-fidelity enzyme is purchased from TOYOBO company; Restriction enzyme KpnI, SacI, T4DNA ligase enzyme, DNAMarker etc. are purchased from TaKaRa company; Glue reclaims test kit, mini-scale plasmid extraction test kit is Omega Products; It is QIAGEN Products that QIAampDNA extracts test kit; Pancreas peptone soybean broth (TSB), agar powder are purchased from Huankai Microbes Tech Co., Ltd., Guangdong; Yeast extract (YeastExtract is called for short YE) is purchased from OXOID company.
Triptic soya yeast extract broth culture (TSB-YE) prepares as follows: pancreas peptone soybean broth (TSB) 30g, YE2g, be dissolved in 1000mL tri-distilled water, heated and stirred is even, 121 DEG C of autoclaving 15min, and cooling is placed on 4 DEG C of preservations.
Triptic soya yeast extract agar substratum (TSA-YE) prepares as follows: pancreas peptone soybean broth (TSB) 30g, YE2g, be dissolved in 1000mL tri-distilled water, adding agar powder to final concentration is 1.5%(w/v), after heated and stirred is even, 121 DEG C of autoclaving 15min, to be cooledly to be distributed in sterilizing plate to about 60 DEG C, to solidify rear 4 DEG C of preservations.
Triptic soya yeast extract agar substratum (TSA-YE) containing paraxin prepares as follows: by after Triptic soya yeast extract agar substratum (TSA-YE) sterilizing for preparing, paraxin (final concentration is 5 μ g/mL) is added when being cooled to 40 ~ 50 DEG C, be distributed into after mixing in sterilizing plate, solidify rear 4 DEG C of preservations.
TSA-YE-Sucrose Selective agar medium prepares as follows: by after Triptic soya yeast extract agar substratum (TSA-YE) sterilizing for preparing, the sucrose that concentration degerming is after filtration mass volume ratio (g/mL) 50% is added when being cooled to 60 ~ 70 DEG C, the final concentration of sucrose is made to be mass volume ratio (g/mL) 7%, be distributed into after mixing in sterilizing plate, solidify rear 4 DEG C of preservations.
2. Brucella melitensis (Brucellamelitensis) M5 strain is purchased from Xinjiang Tiankang Raise Livestock Biotechnology Co., Ltd.
3. following biomaterial is all open in document " structure of brucella bp26 gene-deleted strain; Chinese veterinary science; 2011; 41(03): 280-286 ": Brucella melitensis gene-deleted strain M5-Δ bp26, bacillus coli DH 5 alpha λ pir(genotype are supE44 Δ lacU169 (φ 80lacZ Δ M15) hsdR17recA1endA1gyrA96thi-relA1 λ pi) and pRE112 suicide plasmid (cat, sacB, oriT
rP4, oriV
r6K, MCS).
4. following methods is all open in patent application " Brucella abortus recombinant bacterial strain S19-Δ bp26-BL and preparation method thereof and application, 201310153715.6 ": the preparation method of BL fusion rotein.
Embodiment 1
(1) structure of Suicide homologous recombination plasmid
1. the extraction of brucella genomic dna: illustrate according to QIAampDNA extraction agent box and extract Brucella melitensis M5 pnca gene group DNA.
2. the Design and synthesis of primer: with reference to the gene order of Brucella melitensis (CP001489.1) in Genbank, experimental Demand Design primer, as shown in table 1.Wherein primer P1 and P2 is for the upstream homology arm of the znuA gene that increases, primer P3 and P4 for the downstream homology arm of the znuA gene that increases, and introduces the restriction enzyme site of KpnI and SacI respectively at the 5 ' end of primer P1 and P4.Above-mentioned primer synthesizes by Shanghai Li Fei Bioisystech Co., Ltd.
Table 1 is for the PCR primer sequence of the different genes fragment that increases
Primer | Sequence 5 ' → 3 ' |
P1 | 5′-GATGGTACCCGTCCTCGTTTGCTTGTGC-3′ |
P2 | 5′-TCGCTGAAAGACTGCCTGT-3′ |
P3 | 5′-GCAGTCTTTCAGCGAAGCCAGAAAGGCAGAAGC-3′ |
P4 | 5′-AGAGAGCTCCAATGTCCCCTTGGTCCC-3′ |
3. the pcr amplification of different genes fragment: with the genomic dna of Brucella melitensis M5 strain for template, the upstream and downstream homology arm fragment of the znuA gene that increases respectively with corresponding primer (P1/P2, P3/P4); Utilize the method for OverlapPCR, with the upstream and downstream homology arm of znuA gene for template, increase with primer P1 and P4, obtain the fragment Δ znuA of the disappearance znuA gene that arm before and after is connected.The PCR reaction system of the upstream and downstream homology arm of amplification znuA gene is: 2 × LBuffer12.5 μ L, dNTPs5 μ L, P1(P3) and P2(P4) each 1 μ L, KOD-FX enzyme 0.5 μ L, DNA profiling 1.0 μ L, adds ddH
2o makes cumulative volume reach 25 μ L; Response procedures is: 94 DEG C of 2min; 98 DEG C of 10s, 56 DEG C of 30s, 68 DEG C of 1.5min, 30 circulations, 68 DEG C of 5 ~ 10min.The OverlapPCR reaction system of amplification Δ znuA fragment is each 1.0 μ L of 2 × LBuffer12.5 μ L, dNTPs5 μ L, P1 and P4, and KOD-FX enzyme 1.5 μ L, znuA upstream region of gene homology arm 1.0 μ L and znuA downstream of gene homology arm 1.0 μ L, add ddH
2o makes cumulative volume reach 25 μ L: response procedures is: 94 DEG C of 2min; 98 DEG C of 10s, 56 DEG C of 30s, 68 DEG C of 3min, 30 circulations, 68 DEG C of 5 ~ 10min.
Detected by the agarose gel electrophoresis of mass volume ratio (g/mL) 1%, result as shown in Figure 1, the size of the upstream homology arm of znuA gene is 1149bp, the size of the downstream homology arm of znuA gene is 1098bp, the be connected size of the gene fragment Δ znuA obtained of the upstream and downstream homology arm gene fragment of znuA gene is 2247bp, conforms to theoretical value.
4. the structure of Suicide homologous recombination plasmid: respectively double digestion is carried out to suicide plasmid carrier pRE112 and Δ znuA with KpnI and SacI, wherein, plasmid pRE112 double digestion reaction system is: 10 × LBuffer2.0 μ L, the each 2.0 μ L of KpnI and SacI, pRE112(concentration≤1 μ g/ μ L) 2.0 μ L, add ddH
2o makes cumulative volume reach 20 μ L; DNA fragmentation Δ znuA double digestion reaction system is: 10 × LBuffer2.0 μ L, KpnI and SacI each 2.0 μ L, Δ znuA6.0 μ L, adds ddH
2o makes cumulative volume reach 20 μ L.Fragment Δ znuA enzyme being cut the recovery of rear purifying is connected with carrier segments pRE112 T4DNA ligase enzyme (reaction system and the operation of reaction conditions by specification), and connection product conversion is entered bacillus coli DH 5 alpha λ pir, primer P1 and P4 is used through PCR() identify that correct positive colony carries out plasmid extraction, KpnI and SacI double digestion is verified, result as shown in Figure 2, the fragment that enzyme cuts rear acquisition is identical with object clip size, carry out gene sequencing, the sequence of the sequence obtained and Δ znuA is completely the same, shows to obtain Suicide homologous recombination plasmid pRE-Δ znuA.
(2) structure of Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA and screening
1. the preparation of Brucella melitensis gene-deleted strain M5-Δ bp26 competent cell: single bacterium colony of inoculation M5-Δ bp26 strain, in 100mLTSB-YE substratum, 37 DEG C, 200r/min shaking table is cultivated, is cultured to OD600 and is about 0.6, cooled on ice 30min.The centrifugal 10min of 4000r/min, discards substratum, washs 3 times with the aqueous glycerin solution of volume percent 10%.Finally the thalline of acquisition is resuspended in the aqueous glycerin solution of 2.5mL volume percent 10%, namely obtains Brucella melitensis M5-Δ bp26 competent cell.Be sub-packed in the Eppendorf tube of precooling by 100 μ L/ pipes, put-80 DEG C of Refrigerator stores for subsequent use.
2. transformed by electricity, Bio-rad electric shock cup 1mm, 1.8kv, recombination suicide vector pRE-Δ znuA imports in Brucella melitensis gene-deleted strain M5-Δ bp26 competent cell by 400 Ω, bacterium liquid after being turned by electricity is coated on the TSA-YE flat board containing paraxin (5 μ g/mL), cultivate more than 48h for 37 DEG C, under the selective pressure of paraxin, obtain pRE-Δ znuA and be integrated into homologous recombination list recon on Brucella melitensis gene-deleted strain M5-Δ bp26 genome.Utilize primer P1 and P4 to carry out PCR screening to bacterium colony, PCR response procedures is: 94 DEG C of 2min denaturations; 98 DEG C of 10s, 56 DEG C of 30s, 68 DEG C of 4min, 30 circulations; 68 DEG C of 5 ~ 10min.PCR qualification result as shown in Figure 3, has band at 3180bp and 2247bp place respectively, proves to obtain homologous recombination list recon.
3. bacterium colony PCR is identified correct homologous recombination list recon in TSB-YE, 37 DEG C, 18h cultivated by 200r/min shaking table, after lax plasmid resistance, suitable dilution spread is on TSA-YE-Sucrose Selective agar medium, cultivate more than 48h for 37 DEG C, utilize the susceptibility of sacB gene pairs sucrose in plasmid pRE-Δ znuA, obtain homologous recombination double exchange.Utilize primer P1 and P4 to carry out PCR screening to bacterium colony, PCR response procedures is: 94 DEG C of 2min denaturations; 98 DEG C of 10s, 56 DEG C of 30s, 68 DEG C of 4min, 30 circulations; 68 DEG C of 5 ~ 10min.There are two kinds of situations: one is that pRE-Δ znuA is again from karyomit(e) disappearance (reverse mutation) at homologous recombination double exchange of TSA-YE-Sucrose grow on plates; Two is that Δ znuA gene integration is to genome, and lose in parent znuA gene swapping to carrier, PCR qualification result is done as shown in Figure 4 to homologous recombination double exchange, band is 2247bp(and swimming lane 4,5,7,12) homologous recombination double exchange son be the Brucella melitensis recombinant bacterial strain that will screen, by its called after Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA.
(3) the genetic stability checking of Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA
Obtained M5-Δ bp26-Δ znuA was reached for 20 generations continuously on TSA-YE flat board, with primer P1, P4, pcr amplification is carried out to the bacterium colony on TSA-YE flat board, in every two generations, carry out a bacterium colony PCR and order-checking qualification, the genetic stability of checking recombinant bacterium, result as shown in Figure 5, all increase and obtain the band of 2247bp, show that M5-Δ bp26-Δ znuA has good genetic stability.
(4) growth curve of Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA measures
Parent plant M5 and recombinant bacterial strain M5-Δ bp26-Δ znuA is lined on TSA-YE flat board respectively, after growing single bacterium colony, by single colony inoculation in fresh TSB-YE nutrient solution, 37 DEG C, 220r/min shakes bacterium and is about 20h, logarithmic phase is reached to bacterium, collect thalline, bacterial concentration is adjusted to same numerical value (OD600=0.6), be inoculated in 200mLTSB-YE nutrient solution according to the ratio of volume ratio 1:100, 37 DEG C, 200r/min cultivates, a certain amount of bacterium liquid is taken out every 4h, measure OD value and do 10 times of serial dilutions, be applied in the training of TSA-YE flat board, each extent of dilution 3 flat boards.After bacterium colony grows, count and add up, drawing growth curve as shown in Figure 6, through the growth characteristics of statistical analysis two kinds of bacterial strains there are no significant difference.
(5) Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA virulence determination test
1. the preparation of Brucella melitensis recombinant bacterial strain M5-Δ znuA: be that Suicide homologous recombination plasmid pRE-Δ znuA step (1) obtained is transformed into Brucella melitensis M5 strain, the preparation of Brucella melitensis M5 strain competent cell and Suicide homologous recombination plasmid pRE-Δ znuA is transformed into Brucella melitensis M5 strain, the preparation method of the single, double recon of homologous recombination operates by step (2).
2. by the female BAl BIc in 60 5 ~ 6 week ages/c mouse (Guangdong Medical Lab Animal Center), 5 groups are divided into by often organizing 12.By 1 × 10
8dosage of inoculation intraperitoneal inoculation M5, M5-Δ znuA, M5-Δ bp26 and M5-Δ bp26-Δ znuA respectively of CFU/ mouse, simultaneously using the PBS solution of 10mM, pH7.4 as blank group.BALB/c mouse neck is broken execution in after inoculation the 2nd, 4,6,8 week, often organize 3, eyeball venous blood collection, centrifuging and taking serum.Aseptic spleen of getting is weighed and by spleen homogenate, is made 10 times of serial dilutions after homogenate, and get 100 μ L and be coated with TSA-YE flat board, 37 DEG C of cultivations, laggard row data statistic analysis appears in bacterium colony.
The result display of Fig. 7, change from spleen weight, at immune mouse after 2 weeks, spleen swelling degree caused by M5-Δ bp26-Δ znuA and inflammatory reaction intensity are all obviously weaker than parent plant M5, the two has significant difference, equally also obviously be weaker than two single gene-deleted strain M5-Δ znuA and M5-Δ bp26, significant difference; Simultaneously, as shown in Figure 8, from spleen bacterium number change data, immune mouse is after 2 weeks, M5-Δ bp26-Δ znuA bacterial strain bacterium quantity of (in spleen) in Mice Body is few compared with parent plant M5 and single gene-deleted strain M5-Δ znuA, M5-Δ bp26, there is significant difference, and in ensuing duration of immunity, maintain lower bacterium numbers of states always; 4,6,8 weeks after immunity, M5-Δ bp26-Δ znuA bacterial strain presents to reduce gradually and is excluded and cleans out external process in mouse spleen, and the speed that in this process, M5-Δ bp26-Δ znuA bacterial strain is excluded is still faster than parent plant M5 and two single gene-deleted strain M5-Δ znuA and M5-Δ bp26, there is significant difference, the 8th week time, finally can be observed mouse body two disappearance M5-Δ bp26-Δ znuA bacterial strain is removed totally substantially.Above result shows that M5-Δ bp26-Δ znuA has compared with parent plant M5 and single gene-deleted strain M5-Δ znuA, M5-Δ bp26 and causes the advantage that body inflammatory reacts more weak, virulence is less, security is better.
(6) Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA specific antibody level detection experiment
By the female BAl BIc in 60 5 ~ 6 week ages/c mouse (Guangdong Medical Lab Animal Center), be divided into 5 groups by often organizing 12.By 5 × 10
5dosage of inoculation intraperitoneal inoculation M5, M5-Δ znuA, M5-Δ bp26 and M5-Δ bp26-Δ znuA respectively of CFU/mice, simultaneously using the PBS solution of 10mM, pH7.4 as blank group.BALB/c mouse neck was broken execution in after inoculation the 2nd, 4,6,8 week, often organize 3, eyeball venous blood collection, centrifuging and taking serum is as sample to be checked, the BL fusion rotein prepared with this laboratory is as antigen coated elisa plate, detect the level of the specific antibody of anti-BL in serum, and carry out statistical analysis, step is as follows:
1. the preparation of BL fusion rotein: 1. prepare by patent application 201310153715.6 embodiment 1 step (6), specific as follows: respectively double digestion to be carried out to pET32a expression vector and the correct Δ bp26-BL of gene sequencing with KpnI and SacI, the reaction system of double digestion is: 10 × LBuffer2.0 μ L, the each 2.0 μ L of KpnI and SacI, pET32a(concentration≤1 μ g/ μ L) 2.0 μ L, Δ bp26-BL6.0 μ L, adds ddH
2o makes cumulative volume reach 20 μ L.The fragment Δ bp26-BL reclaimed by purifying is connected with carrier segments pET32a T4DNA ligase enzyme (reaction system and the operation of reaction conditions by specification), and connection product conversion is entered to express in bacterium e. coli bl21 (DE3) (purchased from Novagen company, production code member: 69449-3).The mono-colony inoculation of picking BL-pET-Δ bp26-BL in containing in the LB liquid nutrient medium of penbritin (final concentration is 100 μ g/mL), 37 DEG C, after 200r/min incubated overnight.Get above-mentioned cultivation bacterium by volume 1:50 ratio be inoculated in fresh in the LB nutrient solution of penbritin (final concentration is 100 μ g/mL), 37 DEG C, 200r/min cultivates 3h, adding IPTG(final concentration is 1.5mmol/L) induction time 4h, collection thalline.After ultrasonication, through HisTrapFF purification of recombinant proteins, obtain the BL fusion rotein that purifying is good.
2. BL-iELISA method detects M5-Δ bp26-Δ znuA specific antibody level: using the BL fusion rotein after purifying as envelope antigen, with coating buffer (pH=9.60.05mol/L carbonate buffer solution: Na
2cO
31.59g, NaHCO
32.93g adding distil water is to 1L) be diluted to 100 μ g/mL, every hole adds 100 μ L, and 4 DEG C are spent the night, with lavation buffer solution PBST(at pH=7.4,0.15M phosphate buffered saline buffer adds Tween-20, and the final concentration of Tween-20 is volume percent 0.05%, specifically composed as follows: KH
2pO
40.2g, Na
2hPO
412H
2o2.9g, NaCl8g, KCl0.2g, Tween-200.5mL, distilled water is settled to 1L) washing 3 times, each 3min, pats dry; Every hole adds the skim-milk 200 μ L of mass volume ratio (g/mL) 1%, 37 DEG C of closed 3h, and washing methods is the same; Respectively with M5, M5-Δ bp26-Δ znuA, M5-Δ bp26 of above-mentioned collection and the serum of M5-Δ znuA bacterial strain immune mouse after 2,4,6,8 weeks as serum to be checked (P value), 2 ~ 8 weeks serum of PBS immune mouse are as blank (N value), 20 μ L/ holes add enzyme plate and erect row first hole, again by the first perpendicular row μ L/ hole, hole 180, all the other 100 μ L/ holes add two anti-diluents, carry out transverse direction 10 times of doubling dilutions, 37 DEG C of effect 1h, washing methods is the same; Every hole adds the sheep anti mouse HRP-IgG(1:5000 of horseradish peroxidase-labeled) 100 μ L, 37 DEG C of effects 1h, PBST wash 5 times, and each 3min, pats dry; Every hole adds the substrate nitrite ion TMB(substrate buffer solution of 100 μ L: Na
2hPO
414.6g, citric acid 9.33g, 0.75%H
2o
26.4mL, pH=5.4, distilled water is settled to 1L; TMB uses liquid: TMB200g, dehydrated alcohol 100mL; Get substrate buffer solution 950 μ L and TMB during use and use liquid 50 μ L mixing, be nitrite ion), 37 DEG C of darkroom effect 10min, then add stop buffer (2mol/L sulfuric acid) 50 μ L termination reaction, in 2min, measure OD450nm value with enzyme mark detector.
As shown in Figure 9, recombinant bacterial strain M5-Δ bp26-Δ znuA experimental group small mouse specific antibody was immunity the 6th week, and serum-dilution is than reaching the highest during 1:80 for result.Meanwhile, as can be seen from Figure 10, the specific antibody amount produced compared with parent plant M5, single gene-deleted strain M5-Δ bp26 and M5-Δ znuA at immunity the 6th week couple of deletion mycopremna M5-Δ bp26-Δ znuA is the highest, in significant difference.Thus can infer, new generation vaccine strain M5-Δ bp26-Δ znuA, while reduction virulence, still can stimulate body to produce the antibody of high density, keep high-quality immune effect not subtract.
Above-described embodiment is the present invention's preferably embodiment; but embodiments of the present invention are not restricted to the described embodiments; change, the modification done under other any does not deviate from spirit of the present invention and principle, substitute, combine, simplify; all should be the substitute mode of equivalence, be included within protection scope of the present invention.
Claims (10)
1. the preparation method of a strain Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA, is characterized in that comprising the following steps:
(1) structure of Suicide homologous recombination plasmid
1. be that template carries out PCR with Brucella melitensis (Brucellamelitensis) M5 genomic dna, when the primer of use is for P1 and P2, obtain the upstream homology arm of znuA gene; When the primer used is for P3 and P4, obtain the downstream homology arm of znuA gene;
P1:5′-GATGGTACCCGTCCTCGTTTGCTTGTGC-3′;
P2:5′-TCGCTGAAAGACTGCCTGT-3′;
P3:5′-GCAGTCTTTCAGCGAAGCCAGAAAGGCAGAAGC-3′;
P4:5′-AGAGAGCTCCAATGTCCCCTTGGTCCC-3′;
2. utilize the method for OverlapPCR, with step, 1. the upstream homology arm of the znuA gene of middle preparation and the downstream homology arm of znuA gene are for template, P1 and P4 is primer pair, obtains the object fragment Δ znuA for homologous recombination;
3. double digestion is carried out, purifying to suicide plasmid carrier pRE112 with for the object fragment Δ znuA of homologous recombination respectively with KpnI and SacI; The fragment Δ znuA that purifying reclaims is connected with carrier segments pRE112, obtains Suicide homologous recombination plasmid pRE-Δ znuA;
(2) structure of Brucella melitensis recombinant bacterial strain and screening
1. Suicide homologous recombination plasmid pRE-Δ znuA is imported in the competent cell of Brucella melitensis M5-Δ bp26; Then coat on the TSA-YE flat board containing paraxin, under the selective pressure of paraxin, obtain homologous recombination list recon; PCR is identified correct homologous recombination list recon is cultivated in TSB-YE, lax plasmid resistance;
2. then the homologous recombination list recon after lax plasmid resistance is coated on TSA-YE-Sucrose Selective agar medium and cultivate, utilize the susceptibility of sacB gene pairs sucrose in Suicide homologous recombination plasmid pRE-Δ znuA, suicide plasmid is eliminated, primer P1 and P4 is utilized to carry out PCR screening to the bacterium colony that TSA-YE-Sucrose Selective agar medium grows, obtain homologous recombination double exchange, namely obtain Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA;
Described TSA-YE-Sucrose Selective agar medium composed as follows: Triptic soya yeast extract agar substratum+final concentration is the sucrose of mass volume ratio 7%.
2. the preparation method of Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA according to claim 1, is characterized in that: step (1) 1. described in the condition of PCR be 94 DEG C of 2min; 98 DEG C of 10s, 56 DEG C of 30s, 68 DEG C of 1.5min, 30 circulations; 68 DEG C of 5 ~ 10min extend eventually.
3. the preparation method of Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA according to claim 1, is characterized in that: step (1) 2. described in the condition of OverlapPCR be 94 DEG C of 2min denaturations; 98 DEG C of 10s, 56 DEG C of 30s, 68 DEG C of 3min, 30 circulations; 68 DEG C of 5 ~ 10min extend eventually.
4. the preparation method of Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA according to claim 1, is characterized in that: step (2) 1. described in the mode of importing for be imported by electric transform mode.
5. the preparation method of Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA according to claim 4, is characterized in that: the condition that described electricity transforms is 1mm pole cup, 1.8kv, 400 Ω.
6. the preparation method of Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA according to claim 1, is characterized in that: step (2) 1. described in the final concentration of paraxin in described TSA-YE substratum be 5 μ g/mL.
7. the preparation method of Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA according to claim 1, is characterized in that: step (2) 1. described in the condition of cultivation be 37 DEG C, 36 ~ 48h cultivated by 200r/min shaking table;
Step (2) 2. described in the condition of cultivation be 37 DEG C and cultivate 48 ~ 96h.
8. the preparation method of Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA according to claim 1, is characterized in that: step (2) 1. described in PCR be accredited as and identified by primer P1 and P4;
The condition of described PCR qualification is as follows: 94 DEG C of 2min denaturations; 98 DEG C of 10s, 56 DEG C of 30s, 68 DEG C of 3min, 30 circulations; 68 DEG C of 5 ~ 10min.
9. a strain Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA, be is characterized in that: obtained by the preparation method described in any one of claim 1 ~ 8.
10. Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA according to claim 9 is for the preparation of the application prevented and/or treated in the vaccine of brucellosis.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201310542901.9A CN103667334B (en) | 2013-11-05 | 2013-11-05 | Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA and preparation method and application |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201310542901.9A CN103667334B (en) | 2013-11-05 | 2013-11-05 | Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA and preparation method and application |
Publications (2)
Publication Number | Publication Date |
---|---|
CN103667334A CN103667334A (en) | 2014-03-26 |
CN103667334B true CN103667334B (en) | 2015-12-09 |
Family
ID=50306103
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201310542901.9A Active CN103667334B (en) | 2013-11-05 | 2013-11-05 | Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA and preparation method and application |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN103667334B (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103952428B (en) * | 2014-04-11 | 2016-08-17 | 中国人民解放军军事医学科学院军事兽医研究所 | The preparation method of brucella bacterium shell vaccine strain |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103289986A (en) * | 2013-04-27 | 2013-09-11 | 华南农业大学 | Cattle Brucella recombination strain S19-delta bp 26-BL and preparation method and application thereof |
EP2032687B1 (en) * | 2006-06-21 | 2013-09-11 | Universita' degli Studi di Roma " Tor Vergata" | Salmonella enterica strains of reduced pathogenicity, method for their preparation and uses thereof |
-
2013
- 2013-11-05 CN CN201310542901.9A patent/CN103667334B/en active Active
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2032687B1 (en) * | 2006-06-21 | 2013-09-11 | Universita' degli Studi di Roma " Tor Vergata" | Salmonella enterica strains of reduced pathogenicity, method for their preparation and uses thereof |
CN103289986A (en) * | 2013-04-27 | 2013-09-11 | 华南农业大学 | Cattle Brucella recombination strain S19-delta bp 26-BL and preparation method and application thereof |
Non-Patent Citations (4)
Title |
---|
Deletion of znuA Virulence Factor Attenuates Brucella abortus and Confers Protection against Wild-Type Challenge;Xinghong Yang,et al;《Infection and Immunity》;20060731;第74卷(第7期);摘要、第3874页右栏第2段 材料与方法、第3875右栏第1段 结果 * |
以克隆载体为***载体快速构建布鲁氏菌的无痕缺失突变株;王玉飞 等;《微生物学通报》;20070815;第34卷(第4期);摘要、第643页材料与方法 * |
布鲁氏菌bp26基因缺失株的构建;潘文 等;《中国兽医科学》;20110331;第41卷(第3期);摘要、第281页材料与方法 * |
羊种布鲁氏菌M5-90疫苗株bp26基因突变株的构建及其免疫原性研究;李臻;《中国优秀硕士学位论文全文数据库.农业科技辑》;20120515;摘要、前言、第16页第1.1材料与方法、表1-2 * |
Also Published As
Publication number | Publication date |
---|---|
CN103667334A (en) | 2014-03-26 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN103289986B (en) | Brucella abortus recombinant bacterial strain S19-Δ bp26-BL and preparation method thereof and application | |
CN116059333B (en) | Bovine origin A type Pasteurella multocida gene deletion strain and application thereof | |
CN104388368A (en) | Low-endotoxin escherichia coli prokaryotic expression engineering bacterial mutant strain and construction method | |
CN101092605A (en) | Mutant strain of Brucella bacterin with weak poison, constructing method, and application | |
CN107245459A (en) | One plant of haemophilus parasuis and its application | |
CN103952428A (en) | Preparation method for Brucella shell vaccine strain | |
CN101265457B (en) | Vaccine for differentiating porcine actinobacillus pleuropneumonia serum 7-type double-gene deletion mutant of vaccine immunity and virus infection animal and application thereof | |
CN109810933A (en) | 2 type Streptococcus suis apuA gene knockout mutant strains of one kind and its application | |
CN103667334B (en) | Brucella melitensis recombinant bacterial strain M5-Δ bp26-Δ znuA and preparation method and application | |
CN103421728B (en) | Recombinant bordetella bronchiseptica strain, vaccine and use | |
CN104789576B (en) | Yersinia pestis virulence regulator TyrR and its application | |
CN102776134B (en) | Streptococcus suis Serotype 2 (SS2 for short) double-gene deleted live vaccine and its application | |
CN104726387B (en) | A kind of actinobacillus pleuropneumoniae attenuated strain and its prevention pig pleuropneumonia product of preparation | |
CN101294144A (en) | Type II streptococcus suis sa1KR gene knockout mutant strain, preparation method and application thereof | |
CN102676421B (en) | Bordetella bronchiseptica gene deletion strain, vaccine prepared from Bordetella bronchiseptica gene deletion strain and application | |
CN103484397B (en) | The haemophilus parasuis engineered strain of the non-resistant labelling of a kind of hhdA gene delection and construction method thereof | |
CN104498417A (en) | Streptococcus suis chorismate-synthase gene deletion strain, and construction method and application thereof | |
CN102559733A (en) | Building method of lactococcus lactis genetic engineering bacterial strain loaded with clfA gene | |
CN106047783A (en) | Pseudomonas plecoglossicida ExoU gene knockout mutant strain and application thereof | |
CN109468255A (en) | Integrate probiotics clone strain, construction method and the application of single copy function F4 pili operon gene | |
CN103571867B (en) | Brucella melitensis recombinant bacterial strain M5-Δ znuA and preparation method and application | |
CN105316252A (en) | Five-gene-deleted streptococcus suis serotype 2 strain and application | |
CN104946615A (en) | Preparation and application of tilapia-derived Streptococcus agalactiae recombinant GPI (glycosyl phosphatidyl inositol) protein vaccine | |
CN103421731B (en) | A kind of haemophilus parasuis attenuation salmonella seedling | |
CN101962625A (en) | Salmonella choleraesuis gene deletion mutant without resistant marker and vaccine thereof |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
C10 | Entry into substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
C14 | Grant of patent or utility model | ||
GR01 | Patent grant |