Journal Article

Comparison of multidrug resistance gene regions between two geographically unrelated <i>Salmonella</i> serotypes

M. Daly, L. Villa, C. Pezzella, S. Fanning and A. Carattoli

in Journal of Antimicrobial Chemotherapy

Published on behalf of British Society for Antimicrobial Chemotherapy

Volume 55, issue 4, pages 558-561
Published in print April 2005 | ISSN: 0305-7453
Published online April 2005 | e-ISSN: 1460-2091 | DOI: http://dx.doi.org/10.1093/jac/dki015
Comparison of multidrug resistance gene regions between two geographically unrelated Salmonella serotypes

Show Summary Details

Preview

Objectives: The aim of this study was to identify chromosomally integrated genes conferring multidrug resistance to a Salmonella enterica (S.) serotype Typhimurium isolate, phage type DT193, isolated in Ireland and to compare them with resistance genes conferring plasmid-mediated multidrug resistance to a S. Enteritidis isolate from Italy.

Methods: A complete DNA sequence of the regions containing the resistance genes was obtained from the chromosome of the S. Typhimurium DT193 isolate and from the IncI plasmid of the S. Enteritidis isolate. The plasmid was also characterized by conjugation and incompatibility grouping.

Results: Two 10 kb multidrug resistance non-Salmonella Genomic Island 1 type clusters were independently identified in the S. Enteritidis plasmid and in the chromosome of the S. Typhimurium isolate. Detailed characterization identified an IP-type 2 integron containing a dfrA1-aadA1 gene cassette and other common resistance determinants derived from the RSF1010 plasmid.

Conclusions: These multidrug resistance regions originate following chromosomal integration of key resistance markers encountered on plasmids circulating in other Salmonella serotypes. This mechanism of marker acquisition may have future implications for the evolution of similar structures in previously susceptible serotypes, leading to an increased public health risk.

Keywords: antimicrobial resistance; resistance genes; Salmonella spp; integrons; plasmids

Journal Article.  1999 words.  Illustrated.

Subjects: Medical Oncology ; Critical Care

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.