Characterization of plasmids carrying CMY-2 from expanded-spectrum cephalosporin-resistant Salmonella strains isolated in the United States between 1996 and 1998.
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.
Carattoli
A
A
Laboratory of Bacteriology and Mycology, Istituto Superiore di Sanità, 00161 Rome, Italy.
Tosini
F
F
Giles
W P
WP
Rupp
M E
ME
Hinrichs
S H
SH
Angulo
F J
FJ
Barrett
T J
TJ
Fey
P D
PD
D002443:Ceftriaxone / Q000494:pharmacology; D018550:Cephalosporin Resistance / Q000235:genetics*; D002511:Cephalosporins / Q000494:pharmacology; D003227:Conjugation, Genetic; D024901:Drug Resistance, Multiple, Bacterial; D006801:Humans; D008826:Microbial Sensitivity Tests; D010957:Plasmids / Q000235:genetics*; D012475:Salmonella / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D012480:Salmonella Infections / Q000382:microbiology; D012486:Salmonella typhimurium / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D014481:United States; D001618:beta-Lactamases / Q000235:genetics*
D002511:Cephalosporins; D002443:Ceftriaxone; C103022:beta-lactamase CMY-2; D001618:beta-Lactamases