Skip Navigation



JAC Advance Access published online on April 7, 2006
Journal of Antimicrobial Chemotherapy, doi:10.1093/jac/dkl127
This Article
Right arrow FREE Full Text (PDF) Freely available
Right arrow All Versions of this Article:
57/6/1210    most recent
dkl127v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Guerra, B.
Right arrow Articles by Beutin, L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Guerra, B.
Right arrow Articles by Beutin, L.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author 2006. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oxfordjournals.org
Received December 1, 2005
Accepted March 16, 2006

Brief report

Phenotypic and genotypic characterization of antimicrobial resistance in Escherichia coli O111 isolates

Beatriz Guerra 1 *, Ernst Junker 1, Andreas Schroeter 1, Reiner Helmuth 1, Beatriz E. C. Guth 2, and Lothar Beutin 1

1 Federal Institute for Risk Assessment (BfR), Diedersdorfer Weg 1, D-12277 Berlin, Germany
2 Universidade Federal de São Paulo, Escola Paulista de Medicina, CEP 04023-062, São Paulo, Brazil

* To whom correspondence should be addressed.
Beatriz Guerra, E-mail: b.guerra{at}bfr.bund.de


  Abstract

Objectives: The aim of this study was to generate baseline data on the prevalence and molecular basis of antimicrobial resistance in Escherichia coli O111 isolates.

Methods: A total of 105 epidemiologically unrelated E. coli O111 isolates from humans and cattle (isolated between 1983 and 2003) were tested for susceptibility to 17 antimicrobial agents by broth microdilution. Resistant isolates were screened by molecular methods for resistance genes, class 1 and 2 integrons and mutations in the quinolone-resistance determining regions.

Results: Resistance was found in 76% of the isolates, with a prevalence of 72% for multiresistance. The most prevalent resistances were to streptomycin, sulfamethoxazole and tetracycline (72-68%), followed by spectinomycin, ampicillin and kanamycin/neomycin (39-25%). For each antimicrobial agent, the predominant resistance genes were ampicillin, blaTEM (94%); chloramphenicol, catA1 (100%); gentamicin, aac(3)-IV and aac(3)-II (50% each); kanamycin, aphA1 (100%); streptomycin, aadA1- like (66%); sulfamethoxazole, sul1 (59%); tetracycline, tet(A) (86%); and trimethoprim, dfrA1-like (83%). Class 1 integrons were found in 41% of the isolates. They carried aadA1, dfrA1-aadA1 and dfrA15-aadA1. A class 2 integron (dfrA1-sat1-aadA1) was found in one isolate. Only three isolates (3%) were resistant to nalidixic acid (reduced susceptibility to ciprofloxacin), with a single mutation in the gyrA gene.

Conclusions: E. coli O111 strains exhibit a wide repertoire of genetic elements to sustain antimicrobial pressure. Two specific antimicrobial resistance pheno/genotypes, [STR-SPT]-SUL-TET/aadA1-sul1-tet(A) and STR-SUL-TET-AMP-[KAN-NEO]/strA/B-sul2-tet(A)-blaTEM-aphA1, are predominant.

Keywords: STEC; molecular epidemiology; resistance genes; resistance determinants; integrons.
Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 Appl. Environ. Microbiol.Home page
D. Bibbal, V. Dupouy, M. F. Prere, P. L. Toutain, and A. Bousquet-Melou
Relatedness of Escherichia coli Strains with Different Susceptibility Phenotypes Isolated from Swine Feces during Ampicillin Treatment
Appl. Envir. Microbiol., May 15, 2009; 75(10): 2999 - 3006.
[Abstract] [Full Text] [PDF]

Home page
 Appl. Environ. Microbiol.Home page
K. Ziebell, M. Steele, Y. Zhang, A. Benson, E. N. Taboada, C. Laing, S. McEwen, B. Ciebin, R. Johnson, and V. Gannon
Genotypic Characterization and Prevalence of Virulence Factors among Canadian Escherichia coli O157:H7 Strains
Appl. Envir. Microbiol., July 15, 2008; 74(14): 4314 - 4323.
[Abstract] [Full Text] [PDF]

Home page
 J. Bacteriol.Home page
A. I. Nwaneshiudu, T. Mucci, D. J. Pickard, and I. N. Okeke
A Second Large Plasmid Encodes Conjugative Transfer and Antimicrobial Resistance in O119:H2 and Some Typical O111 Enteropathogenic Escherichia coli Strains
J. Bacteriol., August 15, 2007; 189(16): 6074 - 6079.
[Abstract] [Full Text] [PDF]

Home page
 J. Clin. Microbiol.Home page
L. Beutin and E. Strauch
Identification of Sequence Diversity in the Escherichia coli fliC Genes Encoding Flagellar Types H8 and H40 and Its Use in Typing of Shiga Toxin-Producing E. coli O8, O22, O111, O174, and O179 Strains
J. Clin. Microbiol., February 1, 2007; 45(2): 333 - 339.
[Abstract] [Full Text] [PDF]


Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.