Linkage of heat-stable enterotoxin activity and ampicillin resistance in a plasmid isolated from an Escherichia coli strain of human origin

1980 ◽  
Vol 30 (2) ◽  
pp. 617-620
Author(s):  
H Stieglitz ◽  
R Fonseca ◽  
J Olarte ◽  
Y M Kupersztoch-Portnoy
Keyword(s):  
Escherichia Coli ◽  
Genetic Analysis ◽  
Restriction Endonuclease ◽  
Coli Strain ◽  
Human Origin ◽  
Ampicillin Resistance ◽  
Heat Stable ◽  
Ecori Restriction

In an Escherichia coli strain of human origin, ampicillin resistance and heat-stable enterotoxin activity were shown by EcoRI restriction endonuclease and genetic analysis to be in an 80-megadalton plasmid.

scholarly journals Plasmid Coding for Drug Resistance and Production of Heat-Labile and Heat-Stable Toxins Harbored by an Escherichia coli Strain of Human Origin

1983 ◽  
Vol 39 (2) ◽  
pp. 970-973 ◽  
Author(s):  
M. Lourdes M. Silva ◽  
Isabel C. A. Scaletsky ◽  
M. Henriqueta L. Reis ◽  
M. Heloiza T. Affonso ◽  
Luiz R. Trabulsi
Keyword(s):  
Escherichia Coli ◽  
Drug Resistance ◽  
Coli Strain ◽  
Human Origin ◽  
Heat Stable ◽  
Heat Labile

scholarly journals Transposition of ampicillin resistance to an enterotoxin plasmid in an Escherichia coli strain of human origin.

1979 ◽  
Vol 139 (2) ◽  
pp. 346-355 ◽  
Author(s):  
M M McConnell ◽  
G A Willshaw ◽  
H R Smith ◽  
S M Scotland ◽  
B Rowe
Keyword(s):  
Escherichia Coli ◽  
Coli Strain ◽  
Human Origin ◽  
Ampicillin Resistance

Purification by Affinity Chromatography of Glutathione Reductase (EC 1.6.4.2) from Escherichia coli and Characterization of such Enzyme

1984 ◽  
Vol 39 (9-10) ◽  
pp. 908-915 ◽  
Author(s):  
Anna M. Mata ◽  
M. Carmen ◽  
Juan López-Barea
Keyword(s):  
Escherichia Coli ◽  
Affinity Chromatography ◽  
Glutathione Reductase ◽  
Specific Activity ◽  
Total Yield ◽  
Coli Strain ◽  
Affinity Column ◽  
Heat Stable ◽  
Activity Loss ◽  
Fast Procedure

Abstract The glutathione reductase from Escherichia coli strain S33 was purified to homogeneity by a simple and fast procedure consisting of two affinity chromatography steps. After 40-80% ammonium sulfate fractionation, the enzyme was adsorbed to an N6-2′.5′-ADP-Sepharose affinity column from which it was specifically eluted by a 0 - 10 mᴍ NADP+ linear gradient. The enzyme was finally purified to homogeneity after a second affinity chromatography step in a C8-ATPR-Sepharose column, from which it was eluted by means of the same NADP+ gradient. Starting from 182 g of E. coli cells. 6.9 mg of pure enzyme was obtained after a 2632-fold purifi­cation, with a total yield of 63%. The pure enzyme showed a specific activity of 361 U/mg, and its absorption spectrum was characteristic of a flavoprotein. with an A272A450 of 7.84. The enzyme was a dimer with a molecular weight 109 000 and 40 Å hydrodynamic radius. The optimum pH were 7.5 and 4.5 with NADPH and NADH. respectively, as reductants. Apparent K′m values of 16, 377, and 66 μᴍ were determined at pH 7.5 for NADPH, NADH, and GSSG, respectively. Upon storage the enzyme was stable at pH values ranging from 7.5 to 9.5, being additionally stabilized by FAD. NADP+, dithiothreitol, or glycerol. The pure enzyme was quite heat stable, denaturing signifi­cantly only after 10 min at 70 0C. A marked activity loss was observed however, even at 0 °C, in the presence of 20 μᴍ NADPH. The enzyme was inactivated by low concentrations of para- hydroximercuribenzoate: the sensitivity towards such mercurial was greatly enhanced after reduction of the enzyme by NADPH.

scholarly journals Prevalence of a Gene Encoding Adhesin Involved in Diffuse Adherence among Escherichia Coli Isolates in Pigs with Postweaning Diarrhea or Edema Disease

2003 ◽  
Vol 15 (4) ◽  
pp. 378-381 ◽  
Author(s):  
Seung-Kwon Ha ◽  
Changsun Choi ◽  
Chanhee Chae
Keyword(s):  
Escherichia Coli ◽  
Shiga Toxin ◽  
Coli Strain ◽  
Isolation Rate ◽  
Gene Encoding ◽  
Edema Disease ◽  
E Coli ◽  
Heat Stable ◽  
Fimbrial Adhesins ◽  
Postweaning Diarrhea

A total of 604 Escherichia coli strains isolated from weaned pigs with diarrhea or edema disease on 653 swine farms were screened for the presence of the adhesin involved in diffuse adherence (AIDA) gene by polymerase chain reaction (PCR). Escherichia coli isolates that carried AIDA genes were also tested by PCR for the detection of 5 fimbriae (F4, F5, F6, F18, and F41), 3 heat-stable (STa, STb, and EAST1) and 1 heat-labile (LT) enterotoxin, and Shiga toxin 2e (Stx2e) genes. Forty-five (7.5%) of the 604 E. coli isolates carried the gene for AIDA. Of these 45 isolates, 5 (11.1%) carried EAST1 genes only, 1 (2.2%) carried genes for at least one of the fimbrial adhesins, 12 (26.7%) carried genes for at least one of the toxins, and 27 (60%) carried genes for at least one of the fimbrial adhesins and toxins. Fifty-one percent of strains that carried AIDA genes carried Stx2e genes, and 40% of strains that carried AIDA genes carried F18ab. The isolation rate of enterotoxigenic E. coli strain carrying genes for AIDA was 87%, and the isolation rate of Shiga toxin-producing E. coli strain carrying genes for AIDA was 49%. AIDA may represent an important virulence determinant in pigs with postweaning diarrhea or edema disease.

Sign in / Sign up

Export Citation Format

Share Document