JVDI Advertisement
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Journal of Veterinary Diagnostic Investigation Vol. 20 Issue 3, 342-345
Copyright © 2008 by the American Association of Veterinary Laboratory Diagnosticians
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
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 Download to citation manager
Right arrow reprints & permissions
Google Scholar
Right arrow Articles by Jurado, S.
Right arrow Articles by Domínguez-Bernal, G.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Jurado, S.
Right arrow Articles by Domínguez-Bernal, G.

Brief Communication

Characterization of fluoroquinolone resistance in Escherichia coli strains from ruminants

Sonia Jurado, José A. Orden1, Pilar Horcajo, Ricardo De La Fuente, José A. Ruiz-Santa-Quiteria, Susana Martínez-Pulgarín and Gustavo Domínguez-Bernal

Correspondence: 1Corresponding Author: José A. Orden, Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain, e-mail: jaorden{at}vet.ucm.es

Thirty-seven fluoroquinolone-resistant Escherichia coli strains from ruminants (according to Clinical and Laboratory Standards Institute guidelines) were screened by molecular methods for mutations in the quinolone resistance-determining region (QRDR) of the gyrA and parC genes and for the presence of the qnrA gene. One of the strains studied was an enterohemorrhagic E. coli (EHEC) strain potentially pathogenic for humans. Three E. coli strains resistant to enrofloxacin (minimal inhibitory concentration [MIC] = 2 µg/ml) but not to ciprofloxacin (MIC = 1 µg/ml) presented single mutations in the gyrA and parC genes, while 34 strains resistant to both fluoroquinolones presented double and single mutations in gyrA and parC, respectively (31 strains), or double mutations in gyrA and parC (3 strains). The EHEC strain presented a double amino acid substitution in the GyrA protein (Ser-83->Leu and Asp-87->Gly) and a double amino acid substitution in the ParC protein (Gly-78->Cys and Ser-80->Arg), one of which has not been previously described. The present study shows that most of the mutations in the QRDR of the gyrA and parC genes of fluoroquinolone-resistant E. coli strains from ruminants are the same as those seen in E. coli strains from other animal species and humans and that there are no differences in mutation patterns in the QRDR of E. coli strains from healthy ruminants and those with diarrhea. No strains carried qnrA, which indicates that this gene does not play an important role in the selection of fluoroquinolone-resistant E. coli strains from ruminants.

Key Words: Escherichia coli • fluoroquinolone resistance • gyrA • parC • qnrA • ruminants






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2008 by the American Association of Veterinary Laboratory Diagnosticians, Inc.