Cloning, Expression, Purification, and Characterization of an Organophosphate-Degrading Enzyme in Escherichia Coli

2012 ◽  
Vol 610-613 ◽  
pp. 203-209 ◽  
Author(s):  
Jin Bin Wang ◽  
Da Chao Chen ◽  
Dong Xiao Hu ◽  
Xue Feng Su ◽  
Xue Ming Tang
Keyword(s):  
Escherichia Coli ◽  
Organic Phosphorus ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Cloning And Expression ◽  
E Coli ◽  
Maximum Reaction ◽  
Sds Page ◽  
Protein Expression And Purification ◽  
Optimal Value

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.

scholarly journals Expression in Escherichia coli of the human fibrinogen B beta chain and its cleavage by thrombin

Blood ◽  
1989 ◽  
Vol 73 (5) ◽  
pp. 1202-1206 ◽  
Author(s):  
MG Bolyard ◽  
ST Lord
Keyword(s):  
Escherichia Coli ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Cross Reactivity ◽  
Dependent Manner ◽  
Beta Chain ◽  
Gamma Chain ◽  
Human Fibrinogen ◽  
E Coli ◽  
Sds Page

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.

scholarly journals Expression in Escherichia coli of the human fibrinogen B beta chain and its cleavage by thrombin

Blood ◽  
1989 ◽  
Vol 73 (5) ◽  
pp. 1202-1206
Author(s):  
MG Bolyard ◽  
ST Lord
Keyword(s):  
Escherichia Coli ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Cross Reactivity ◽  
Dependent Manner ◽  
Beta Chain ◽  
Gamma Chain ◽  
Human Fibrinogen ◽  
E Coli ◽  
Sds Page

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.

Structure of the O-chain polysaccharide of the phenol-phase soluble lipopolysaccharide of Escherichia coli 0:157:H7

1986 ◽  
Vol 64 (1) ◽  
pp. 21-28 ◽  
Author(s):  
Malcolm B. Perry ◽  
Leann MacLean ◽  
Douglas W. Griffith
Keyword(s):  
Escherichia Coli ◽  
Brucella Abortus ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Extraction Procedure ◽  
Periodate Oxidation ◽  
Cross Reactivity ◽  
E Coli ◽  
Structure Formula ◽  
Phenol Water

The phenol-phase soluble lipopolysaccharide isolated from Escherichia coli 0:157 by the hot phenol–water extraction procedure was shown by sodium dodecyl sulfate–polyacrylamide gel electrophoresis, periodate oxidation, methylation, and 13C and 1H nuclear magnetic resonance studies to be an unbranched linear polysaccharide with a tetrasaccharide repeating unit having the structure:[Formula: see text]The serological cross-reactivity of E. coli 0:157 with Brucella abortus, Yersinia enterocolitica (serotype 0:9), group N Salmonella, and some other E. coli species can be related immunochemically to the presence of 1,2-glycosylated N-acylated 4-amino-4,6-dideoxy-α-D-mannopyranosyl residues in the O-chains of their respective lipopolysaccharides.

scholarly journals Acetate and Formate Stress: Opposite Responses in the Proteome of Escherichia coli

2001 ◽  
Vol 183 (21) ◽  
pp. 6466-6477 ◽  
Author(s):  
Christopher Kirkpatrick ◽  
Lisa M. Maurer ◽  
Nikki E. Oyelakin ◽  
Yuliya N. Yoncheva ◽  
Russell Maurer ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Opposite Effect ◽  
Stress Proteins ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Acid Resistance ◽  
Luria Broth ◽  
Acetyl Coa ◽  
Fermentation Products ◽  
E Coli

ABSTRACT Acetate and formate are major fermentation products ofEscherichia coli. Below pH 7, the balance shifts to lactate; an oversupply of acetate or formate retards growth. E. coli W3110 was grown with aeration in potassium-modified Luria broth buffered at pH 6.7 in the presence or absence of added acetate or formate, and the protein profiles were compared by two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Acetate increased the steady-state expression levels of 37 proteins, including periplasmic transporters for amino acids and peptides (ArtI, FliY, OppA, and ProX), metabolic enzymes (YfiD and GatY), the RpoS growth phase regulon, and the autoinducer synthesis protein LuxS. Acetate repressed 17 proteins, among them phosphotransferase (Pta). An ackA-pta deletion, which nearly eliminates interconversion between acetate and acetyl-coenzyme A (acetyl-CoA), led to elevated basal levels of 16 of the acetate-inducible proteins, including the RpoS regulon. Consistent with RpoS activation, the ackA-pta strain also showed constitutive extreme-acid resistance. Formate, however, repressed 10 of the acetate-inducible proteins, including the RpoS regulon. Ten of the proteins with elevated basal levels in the ackA-ptastrain were repressed by growth of the mutant with formate; thus, the formate response took precedence over the loss of theackA-pta pathway. The similar effects of exogenous acetate and the ackA-pta deletion, and the opposite effect of formate, could have several causes; one possibility is that the excess buildup of acetyl-CoA upregulates stress proteins but excess formate depletes acetyl-CoA and downregulates these proteins.

The anaerobic sn-glycerol-3-phosphate dehydrogenase: cloning and expression of the glpA gene of Escherichia coli and identification of the glpA products

1982 ◽  
Vol 60 (3) ◽  
pp. 224-231 ◽  
Author(s):  
Anthony Schryvers ◽  
Joel H. Weiner
Keyword(s):  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Phosphate Transport ◽  
Cloning And Expression ◽  
Relative Mass ◽  
Recombinant Plasmids ◽  
Sds Page ◽  
Glycerol 3 Phosphate Dehydrogenase ◽  
Definition Of ◽  
Different Strains

The expression of recombinant plasmids carrying the glpA gene (anaerobic glycerol-3-phosphate dehydrogenase) and the closely linked glpT gene (glycerol 3-phosphate transport) were studied under aerobic and anaerobic conditions. When the pattern of expression of enzymatic activity in different strains was compared with sodium dodecyl sulphate – polyacrylamide gel electrophoresis (SDS–PAGE) analysis from the same cells the glpA products were identified. Two polypeptides of 62 000 and 43 000 relative mass correlated with enzymatic activity.Five recombinant plasmids that contained one or both of the glpT or glpA genes were isolated and subjected to restriction endonuclease cleavage analysis. The regions of overlap from the inserts in these plasmids allowed definition of the regions of DNA containing the glpT and glpA genes. SDS–PAGE analysis revealed a partial product of the glpA locus from one plasmid, pLC42-17, which allowed more precise definition of the glpA locus on the physical DNA map and prediction of the direction of transcription.

Isolation and purification of a Campylobacter upsaliensis autolysin

1999 ◽  
Vol 45 (1) ◽  
pp. 23-30
Author(s):  
Somchai Santiwatanakul ◽  
Noel R Krieg
Keyword(s):  
Escherichia Coli ◽  
Molecular Mass ◽  
Micrococcus Luteus ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Isolation And Purification ◽  
Whole Cells ◽  
Sds Page ◽  
Autolytic Activity ◽  
Campylobacter Upsaliensis

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.

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 ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Mycobacterium Bovis ◽  
Expression Vector ◽  
Fusion Gene ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Antigenic Activity ◽  
Sds Page ◽  
Prokaryotic Expression Vector ◽  
Single Antigen

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.

scholarly journals Cloning and expression of two human p70 S6 kinase polypeptides differing only at their amino termini.

1991 ◽  
Vol 11 (11) ◽  
pp. 5541-5550 ◽  
Author(s):  
J R Grove ◽  
P Banerjee ◽  
A Balasubramanyam ◽  
P J Coffer ◽  
D J Price ◽  
...  
Keyword(s):  
Rat Liver ◽  
Kinase Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Cloning And Expression ◽  
S6 Kinase ◽  
P70 S6 Kinase ◽  
Cos Cells ◽  
Sds Page

Two classes of human cDNA encoding the insulin/mitogen-activated p70 S6 kinase have been isolated; the two classes differ only in the 5' region, such that the longer polypeptide (p70 S6 kinase alpha I; calculated Mr 58,946) consists of 525 amino acids, of which the last 502 residues are identical in sequence to the entire polypeptides encoded by the second cDNA (p70 S6 kinase alpha II; calculated Mr 56,153). Both p70 S6 kinase polypeptides predicted by these cDNAs are present in p70 S6 kinase purified from rat liver, and each is thus expressed in vivo. Moreover, both polypeptides are expressed from a single mRNA transcribed from the (longer) p70 S6 kinase alpha I cDNA through the utilization of different translational start sites. Although the two p70 S6 kinase polypeptides differ by only 23 amino acid residues, the slightly longer alpha I polypeptide exhibits anomalously slow mobility on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), migrating at an apparent Mr of 90,000 probably because of the presence of six consecutive Arg residues immediately following the initiator methionine. Transient expression of p70 alpha I and alpha II S6 kinase cDNA in COS cells results in a 2.5- to 4-fold increase in overall S6 kinase activity. Upon immunoblotting, the recombinant p70 polypeptides appear as a closely spaced ladder of four to five bands between 65 and 70 kDa (alpha II) and 85 and 90 kDa (alpha I). Transfection with the alpha II cDNA yields only the smaller set of bands, while transfection with the alpha I cDNA generates both sets of bands. Mutation of Met-24 in the alpha I cDNA to Leu or Thr suppresses synthesis of the alpha II polypeptides. Only the p70 alpha I and alpha II polypeptides of slowest mobility on SDS-PAGE comigrate with the 70- and 90-kDa proteins observed in purified rat liver S6 kinase. Moreover, it is the recombinant p70 polypeptides of slowest mobility that coelute with S6 kinase activity on anion-exchange chromatography. The slower mobility and higher enzymatic activity of these p70 proteins is due to Ser/Thr phosphorylation, inasmuch as treatment with phosphatase 2A inactivates kinase activity and increases the mobility of the bands on SDS-PAGE in an okadaic acid-sensitive manner. Thus, the recombinant p70 S6 kinase undergoes multiple phosphorylation and partial activation in COS cells. Acquisition of S6 protein kinase catalytic function, however, is apparently restricted to the most extensively phosphorylated recombinant polypeptides.

scholarly journals Cloning, Expression, and Characterization of Fimbrial Operon F9 from Enterohemorrhagic Escherichia coli O157:H7

2006 ◽  
Vol 74 (4) ◽  
pp. 2233-2244 ◽  
Author(s):  
Alison S. Low ◽  
Francis Dziva ◽  
Alfredo G. Torres ◽  
Jessenya L. Martinez ◽  
Tracy Rosser ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Epithelial Cells ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Enterohemorrhagic Escherichia Coli ◽  
Wild Type ◽  
Induced Expression ◽  
E Coli ◽  
Extracellular Matrix Components ◽  
K 12

ABSTRACT Recent transposon mutagenesis studies with two enterohemorrhagic Escherichia coli (EHEC) strains, a sero- type O26:H- strain and a serotype O157:H7 strain, led to identification of a putative fimbrial operon that promotes colonization of young calves (1 to 2 weeks old). The distribution of the gene encoding the major fimbrial subunit present in O-island 61 of EHEC O157:H7 in a characterized set of 78 diarrheagenic E. coli strains was determined, and this gene was found in 87.2% of the strains and is therefore not an EHEC-specific region. The cluster was amplified by long-range PCR and cloned into the inducible expression vector pBAD18. Induced expression in E. coli K-12 led to production of fimbriae, as demonstrated by transmission electron microscopy and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. The fimbriae were purified, and sera to the purified major subunit were raised and used to demonstrate expression from wild-type E. coli O157:H7 strains. Induced expression of the fimbriae, designated F9 fimbriae, was used to characterize binding to bovine epithelial cells, bovine gastrointestinal tissue explants, and extracellular matrix components. The fimbriae promoted increases in the levels of E. coli K-12 binding only to bovine epithelial cells. In contrast, induced expression of F9 fimbriae in E. coli O157:H7 significantly reduced adherence of the bacteria to bovine gastrointestinal explant tissue. This may have been due to physical hindrance of type III secretion-dependent attachment. The main F9 subunit gene was deleted in E. coli O157:H7, and the resulting mutant was compared with the wild-type strain for colonization in weaned cattle. While the shedding levels of the mutant were reduced, the animals were still colonized at the terminal rectum, indicating that the adhesin is not responsible for the rectal tropism observed but may contribute to colonization at other sites, as demonstrated previously with very young animals.

scholarly journals Media Optimization for Production of Recombinant Carrier Protein (CRM197) in Escherichia coli

2021 ◽  
Vol 13 (1) ◽  
pp. 283-297
Author(s):  
S. Shukla ◽  
D. Mishra
Keyword(s):  
Escherichia Coli ◽  
Large Scale ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Luria Bertani ◽  
Lag Phase ◽  
Carrier Protein ◽  
Scale Production ◽  
E Coli ◽  
Defined Media

Since the advent of vaccines, the mankind has benefited from the same and has been able to curb the mortality rate around the globe. Amongst different types of available vaccines, polysaccharide based vaccines are very widely used against various infectious diseases. The polysaccharide vaccines need to be conjugated with a carrier protein to make the vaccine more immunogenic. Recombinant Escherichia coli cells are the organism of choice for large scale production of a carrier protein because of its widely studied scientific aspects. In the present study, for proof of concept, the recombinant E. coli cells were cultured in Luria-Bertani media to check the expression of rCRM197. At 80L scale, it was observed that when recombinant E. coli cells were grown in a chemically defined media, it resulted in inconsistent growth and a long lag phase. When the defined media was supplemented with yeast extract, the lag phase of the culture was substantially reduced and the maximum growth of the culture was achieved. Protein expression was checked using SDS PAGE (Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis) and Western blot technique. The optimized media resulted in a robust fermentation process to achieve high cell density and maximum biomass for the production of recombinant protein.

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