Fusion Expression on the Esat-6 and cfp-10 Genes of Mycobacterium bovis in Escherichia coli

2013 ◽  
Vol 421 ◽  
pp. 354-358
Author(s):  
Jia Ming Lin ◽  
Chun Fang Wang ◽  
Jia Ning Guan ◽  
Hong Xia Ma ◽  
Shuang Hou ◽  
...  

Based on the (Gly4Ser)3 linker, theesat-6andcfp-10gene were fused for raising the antigenicity of single antigen. The DNA fragments ofesat-6andcfp-10were fused by splicing by overlapping extension (SOE) polymerase chain reaction (PCR),and the fusion gene esat-6-cfp-10 were cloned into pMD18-T vector, and then we got the recombinant plasmid pMD-esat-6-cfp-10. pMD-esat-6-cfp-10 and pET28a (+) were digested byBamHI andEcoRI double enzymes. The purified mpb esat-6-cfp-10 fusion gene was subcloned into the expression vector pET28a (+),and the prokaryotic expression vector pET-esat-6-cfp-10 was constructed. Plasmid containing pET-esat-6-cfp-10 was transformed into competenceEscherichia coliBL21(DE3).The bacterium was induced by isopropyl-β-D-thiogalactopyranoside (IPTG) and analyzed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE),approximately 25 kDa exogenous protein was observed on the SDS-PAGE. The protein was analyzed by using Western-blotting. The results indicated that the protein was of antigenic activity ofMycobacterium bovis. These results could serve as a basis for further studies on the usefulness of the fusion gene and its expression product in the development of DNA vaccine; living carrier vaccine; subunit vaccine and diagnostic reagents against bovine tuberculosis.

2014 ◽  
Vol 997 ◽  
pp. 210-214
Author(s):  
Yun Hang Gao ◽  
Yan Liu ◽  
Ying Nan Zhang ◽  
Yan Yu ◽  
Chun Lei Liu ◽  
...  

For raising the antigenicity ofMycobacterium bovissingle antigen, fusion protein of two genes was acquired. The DNA fragments ofmpb83andmpb70were fused by splicing by overlapping extension (SOE) polymerase chain reaction (PCR), and the fusion gene mpb83-mpb70 were cloned into pMD18-T vector, then we got the recombinant plasmid pMD-83-70. pMD-83-70 and pET28a (+) were digested byBamH I andEcoR I double enzymes. The purified pMD-83-70 fusion gene was subcloned into the expression vector pET28a (+), and the prokaryotic expression vector pET-83-70 was constructed. Plasmid containing pET-83-70 was transformed into competenceEscherichia coliBL21 (DE3). The bacterium was induced by isopropyl-β-D-thiogalactoside (IPTG) and the lysates were loaded directly onto sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), approximately 41 kDa exogenous protein was observed on the SDS-PAGE. The protein was analyzed by using Western blotting, the results indicated that the protein was of antigenic activity ofM.bovis. These results could serve as a basis for further studies on the usefulness of the fusion gene and its expression product in the development of subunit vaccine and DNA vaccine against bovine tuberculosis.


2013 ◽  
Vol 791-793 ◽  
pp. 212-215
Author(s):  
Jia Ning Guan ◽  
Chun Fang Wang ◽  
Jia Ming Lin ◽  
Hong Xia Ma ◽  
Shuang Hou ◽  
...  

Based on the (Gly4Ser)3 linker, thempb83andmpb63gene were fused for raising the antigenicity of single antigen. The DNA fragments ofmpb83andmpb63were fused by splicing by overlapping extension (SOE) polymerase chain reaction (PCR) ,and the fusion gene mpb83-63 were cloned into pMD18-T vector, and then we got the recombinant plasmid pMD-83-63. pMD-83-63 and pET28a (+) were digested byBamH I andEcoR I double enzymes. The purified mpb83-63 fusion gene was subcloned into the expression vector pET28a (+),and the prokaryotic expression vector pET-83-63 was constructed. Plasmid containing pET-83-63 was transformed into competence Escherichia coli BL21(DE3).The bacterium was induced by isopropyl-β-D-thioga-lactopyranoside (IPTG) and analyzed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE),approximately 38 kDa exogenous protein was observed on the SDS-PAGE. The protein was analyzed by using Western-blotting. The results indicated that the protein was of antigenic activity ofMycobacterium bovis. These results could serve as a basis for further studies on the usefulness of the fusion gene and its expression product in the development of DNA vaccine; living carrier vaccine; subunit vaccine and diagnostic reagents against bovine tuberculosis.


2014 ◽  
Vol 884-885 ◽  
pp. 498-502
Author(s):  
Xin Liu ◽  
Chun Fang Wang ◽  
Hong Xia Ma ◽  
Yun Hang Gao ◽  
Jia Ning Guan ◽  
...  

Based on splicing by overlapping extension (SOE) polymerase chain reaction (PCR) ,theag85aandmpb70were amplified and the fusion gene ag85a-mpb70 were cloned into pMD18-T vector, and then we got the recombinant plasmid pMD-85a-70. pMD-85a-70 and pET28a (+) were digested byBamHI andEcoRI double enzymes. The purified ag85a-mpb70 fusion gene was subcloned into the expression vector pET28a (+),and the prokaryotic expression vector pET-85a-70 was constructed. Plasmid containing pET-85a-70 was transformed into competenceEscherichia coliBL21(DE3).The bacterium was induced by isopropyl-β-D-thiogalactopyranoside (IPTG) and analyzed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), approximately 49 kDa fusion protein was observed on the SDS-PAGE. The protein was analyzed by using Western-blotting. The results indicated that Ag85A-MPB70 was of antigenic activity ofMycobacterium bovis. These results could serve as a basis for further studies on the usefulness of the fusion gene and its expression product in the development of novel vaccine against bovine tuberculosis.


2013 ◽  
Vol 319 ◽  
pp. 140-145
Author(s):  
Yun Hang Gao ◽  
Chun Fang Wang ◽  
Xiu Yun Jiang ◽  
Hong Xia Ma ◽  
Da Ming Gao ◽  
...  

The DNA fragments of mpb51 and mpb63 were fused by splicing by overlapping extension(SOE) polymerase chain reaction(PCR),and the fusion gene mpb51-63 were cloned into pMD18-T vector, and then we got the recombinant plasmid pMD-51-63. pMD-51-63 and pET28a(+) were digested by BamHI and EcoRI double enzymes. The purified mpb51-63 fusion gene was subcloned into the expression vector pET28a(+),and the prokaryotic expression vector pET-51-63 was constructed. Plasmid containing pET-51-63 was transformed into competence Escherichia coli BL21(DE3).The bacterium was induced by isopropyl-β-D-thiogalactopyranoside(IPTG)and its lysates were loaded directly onto sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE),approximately 43ku exogenous protein was observed on the SDS-PAGE. The protein was analyzed by using Western-blotting. The results indicated that the protein was of antigenic activity of Mycobacterium bovis. These results could serve as a basis for further studies on the usefulness of the fusion gene and its expression product in the development of subunit vaccine, DNA vaccine and diagnostic reagents against bovine tuberculosis.


Blood ◽  
1989 ◽  
Vol 73 (5) ◽  
pp. 1202-1206 ◽  
Author(s):  
MG Bolyard ◽  
ST Lord

Abstract The human fibrinogen B beta chain was expressed in Escherichia coli to study the functions of fibrinogen associated with this subunit. Recombinant B beta chains were expressed at 100 ng/mL in an IPTG- dependent manner. A first cistron sequence, inserted into the expression vector 5′ to the B beta chain cDNA, was required to express the protein. Recombinant B beta chains were expressed within five minutes after induction with IPTG and were soluble in physiologic buffers. The recombinant B beta chains migrated on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) at a rate identical to B beta chains from fibrinogen treated with N-glycanase. Recombinant B beta chains were cleaved by thrombin, as demonstrated by the loss of cross-reactivity with a monoclonal antibody (MoAb) specific for the undigested B beta 1–42 fragment. The levels of expression of the B beta chain were much lower than those reported previously for the gamma chain of fibrinogen expressed in a similar vector in E coli. However, these levels are sufficient to allow further characterization of this fibrinogen subunit.


1999 ◽  
Vol 45 (1) ◽  
pp. 23-30
Author(s):  
Somchai Santiwatanakul ◽  
Noel R Krieg

Autolytic activity in the soluble and sediment fractions of sonicates of the spiral and the coccoid form of Campylobacter upsaliensis could not be demonstrated by native (nondenaturing) polyacrylamide gel electrophoresis (PAGE). Autolysins were detected, however, by using denaturing sodium dodecyl sulfate (SDS) - PAGE gels containing either purified Escherichia coli peptidoglycan or whole cells of Micrococcus luteus (Micrococcus lysodeikticus) as the turbid substrate, with subsequent renaturation by treatment with Triton X-100 buffer. In renaturing gels that contained Escherichia coli peptidoglycan, 14 putative autolytic bands ranging from 200 to 12 kDa were detected. In similar gels containing whole cells of M. luteus, only a single band appeared with a molecular mass of 34 kDa. This band corresponded to one of the bands present in the gels containing Escherichia coli peptidoglycan. This common autolysin was isolated by adsorbing it from Campylobacter upsaliensis soluble fractions onto M. luteus cells and then subjecting these cells to renaturing SDS-PAGE in gels containing Escherichia coli peptidoglycan. The 34-kDa autolysin differed from a single 51-kDa autolysin unique to the M. luteus cells, and when isolated from an SDS-PAGE gel, was pure when tested by isoelectric focusing. The N-terminal amino acid sequence analysis showed the first 15 amino acids of the 34-kDa autolysin to have 67% identity to a part of antigenic protein PEB4 of Campylobacter jejuni. The purified autolysin was used to immunize rabbits and the antibodies produced precipitated autolytic activity from cell lysates. The specificity of the antibodies was shown by Western blotting: only a single specific band occurred, with a molecular mass of 34 kDa, and thus it seems unlikely that the 34-kDa autolysin was derived from any of the other autolysins that were detected.Key words: autolysin, Campylobacter upsaliensis, zymogram, murein hydrolase.


2011 ◽  
Vol 301-303 ◽  
pp. 347-351
Author(s):  
Xiu Hong Zhao ◽  
Jie Zeng ◽  
Hai Yan Gao ◽  
Chang Biao Li ◽  
Chang Jiang Liu

Gene encoding β-glucosidase was amplified through PCR by using the genome DNA extracted from L .delbrueckii subsp. delbrueckii as a template. The gene encoding β-glucosidase was inserted into a prokaryotic expression vector pET-28a(+) and expressed in E.coli strain BL21(DE3). The gene encoding β-glucosidase was of 1380bp. The nucleotide sequence of the gene encoding β-glucosidase from L. delbrueckii subsp. delbrueckii showed as high as 97.9% homology comparing with that from L. delbrueckii subsp. bulgaricus indicating that the gene encoding β-glucosidase is highly conservative. The enzyme activity was about 34U/mg and the molecular weight of β-glucosidase is about 51 kDa analyzed by SDS-polyacrylamide gel electrophoresis.


2010 ◽  
Vol 192 (9) ◽  
pp. 2407-2413 ◽  
Author(s):  
Jacalyn M. Green ◽  
Ryan Hollandsworth ◽  
Lenore Pitstick ◽  
Eric L. Carter

ABSTRACT The abg locus of the Escherichia coli chromosome includes three genes encoding proteins (AbgA, AbgB, and AbgT) that enable uptake and utilization of the folate breakdown product, p-aminobenzoyl-glutamate (PABA-GLU). We report on the purification and characterization of the p-aminobenzoyl-glutamate hydrolase (PGH) holoenzyme encoded by abgA and abgB. One-step purification was accomplished using a plasmid carrying abgAB with a hexahistidine tag on the carboxyl terminus of AbgB and subsequent metal affinity chromatography (MAC). Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed two subunits (∼53-kDa and ∼47-kDa proteins) of the expected masses of AbgB and AbgA; N-terminal sequencing confirmed the subunit identification, and amino acid analysis yielded a 1:1 ratio of the subunits. Size exclusion chromatography coupled with light-scattering analysis of purified PGH revealed a predominant molecular mass of 206 kDa and a minor component of 400 to 500 kDa. Both peaks contained PGH activity, and SDS-PAGE revealed that fractions containing activity were composed of both AbgA and AbgB. MAC-purified PGH was highly stimulated by manganese chloride. Kinetic analysis of MAC-purified PGH revealed a Km value for PABA-GLU of 60 ± 0.08 μM and a specific activity of 63,300 ± 600 nmol min−1 mg−1. Folic acid and a variety of dipeptides served as poor substrates of PGH. This locus of the E. coli chromosome may encode a portion of a folate catabolism pathway.


2005 ◽  
Vol 37 (2) ◽  
pp. 147-151 ◽  
Author(s):  
Pei-Fu Chen ◽  
Hong-Ying Zhang ◽  
Geng-Feng Fu ◽  
Gen-Xing Xu ◽  
Ya-Yi Hou

Abstract Synthesized gene of human thymosin alpha 1 (Tα1) was inserted into pET-28a, pET-9c, pThioHis B, pGEX-2T or pBV222 and then inductively expressed in strains of Escherichia coli. Among the five expression systems, the BL21/pET-28a system provides the highest expression level of fusion protein in a soluble form, which is up to 70% of total expressed bacterial proteins as visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The resulting fusion protein purified through nickel affinity chromatography accounts for 2.53% of the wet bacterial pellet weight and reaches 94.5% purity by SDS-PAGE. These results indicate the potential of this expression system for high-throughput production of recombinant Tα1.


2012 ◽  
Vol 610-613 ◽  
pp. 203-209 ◽  
Author(s):  
Jin Bin Wang ◽  
Da Chao Chen ◽  
Dong Xiao Hu ◽  
Xue Feng Su ◽  
Xue Ming Tang

OpdA is one of organic phosphorus degradation enzyme gene from Agrobacterium radiobacter that may be the most promising targets for the digestion of digestion. In this study, we describe for the cloning and expression in Escherichia coli (E. coli) of plasmid pET28b-opdA, followed by purification by NTA-Ni2+ agarose affinity chromatography. Protein expression and purification were evaluated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE).The Results showed that the optimal value of inoculum OD600 before induction, inducing time, final IPTG concentration and inducing temperature respectively were 0.5,5h,1 mmol/L,37°C. We obtained the concentration of renatured protein was 18.312mg / L. The Km was 4.26μmol/L at 37 °C, and the maximum reaction velocity (Vmax) was 3.2669μmol/L • min.


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