Multiple-antibiotic resistance mediated by structurally related IncL/M plasmids carrying an extended-spectrum beta-lactamase gene and a class 1 integron
L. Villa et al., Multiple-antibiotic resistance mediated by structurally related IncL/M plasmids carrying an extended-spectrum beta-lactamase gene and a class 1 integron, ANTIM AG CH, 44(10), 2000, pp. 2911-2914
A conjugative IncL/M plasmid (pSEM) conferring resistance to gentamicin, am
ikacin, kanamycin, sulfonamides, and expanded-spectrum cephalosporins was f
ound in pathogenic strains of Salmonella enterica serotype Typhimurium. Res
istance to aminoglycosides was encoded by a sul1-type class 1 integron (In-
t3). An extended-spectrum beta-lactamase gene, bla(SHV-5), was identified 3
.5 kb downstream of the integrase (intI1) gene of In-t3. Nucleotide sequenc
e analysis of the 5.3-kb bla(SHV-5)-In-t3 region of pSEM highlighted striki
ng similarities with IncL/M plasmids isolated from nosocomial gram-negative
pathogens, conferring resistance to expanded-spectrum cephalosporins and a
minoglycosides.