Journal Article

High diversity of plasmids harbouring blaCMY-2 among clinical Escherichia coli isolates from humans and companion animals in the upper Midwestern USA

Valeria Bortolaia, Katrine H. Hansen, Christine A. Nielsen, Thomas R. Fritsche and Luca Guardabassi

in Journal of Antimicrobial Chemotherapy

Volume 69, issue 6, pages 1492-1496
Published in print June 2014 | ISSN: 0305-7453
Published online February 2014 | e-ISSN: 1460-2091 | DOI: https://dx.doi.org/10.1093/jac/dku011
High diversity of plasmids harbouring blaCMY-2 among clinical Escherichia coli isolates from humans and companion animals in the upper Midwestern USA

More Like This

Show all results sharing these subjects:

  • Medical Oncology
  • Critical Care

GO

Show Summary Details

Preview

Objectives

To determine the population structure and genetic relatedness of plasmids encoding CMY-2 β-lactamase in clinical Escherichia coli from humans and companion animals within a defined geographical area.

Methods

In total, 42 human and 73 companion animal isolates displaying an AmpC phenotype were isolated at a regional diagnostic reference laboratory in the upper Midwestern USA during 2009–11. Following PCR screening for transferable AmpC genes and plasmid transformation, blaCMY-2-positive plasmids were characterized by S1 nuclease PFGE, PCR-based replicon typing, antimicrobial susceptibility testing of transformants, conjugation experiments, plasmid multilocus sequence typing and restriction fragment length polymorphism.

Results

blaCMY-2 occurred in 6 (14%), 56 (86%) and 6 (75%) isolates from humans, dogs and cats, respectively. Usually plasmids carrying blaCMY-2 were conjugative (78%) and did not contain additional resistance genes (82%). The replicon types were IncI1 (52%), IncA/C (13%), IncFII (10%), IncI2 (5%), IncL/M (3%), IncB/O (2%) or non-typeable (15%). Related IncI1/ST12 plasmids were detected in one human and five canine isolates, while the remaining plasmids did not show similarity across host species. A novel epidemiological linkage of blaCMY-2 with IncL/M plasmids and a new CMY gene variant (blaCMY-108) were found in human isolates.

Conclusions

This study is one of the first One Health attempts to compare plasmids encoding CMY-2 β-lactamase among clinical isolates from humans and companion animals in the same region. The results indicate an unforeseen heterogeneity of plasmid backgrounds and suggest limited exchange between the two populations, in which blaCMY-2 occurred at very different frequencies and was harboured by distinct plasmid types.

Keywords: AmpC; antimicrobial resistance; dogs; cats

Journal Article.  2551 words. 

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. subscribe or login to access all content.