Characterization of plasmids carrying CMY-2 from expanded-spectrum cephalosporin-resistant Salmonella strains isolated in the United States between 1996 and 1998.

Laboratory of Bacteriology and Mycology, Istituto Superiore di Sanità, 00161 Rome, Italy.
Antimicrobial Agents and Chemotherapy (Impact Factor: 4.45). 06/2002; 46(5):1269-72. DOI: 10.1128/AAC.46.5.1269-1272.2002
Source: PubMed

ABSTRACT Sequencing of DNA from 15 expanded-spectrum cephalosporin (e.g., ceftriaxone)-resistant Salmonella isolates obtained in the United States revealed that resistance to ceftriaxone in all isolates was mediated by cmy-2. Hybridization patterns revealed three plasmid structures containing cmy-2 in these 15 isolates. These data suggest that the spread of cmy-2 among Salmonella strains is occurring through mobilization of the cmy-2 gene into different plasmid backbones and consequent horizontal transfer by conjugation.

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