Increased mutation frequencies in Escherichia coli isolates harboring extended-spectrum beta-lactamases.
Hypermutable (mutation frequency [f], > or = 4 x 10(-8)) Escherichia coli strains were more frequently found (43%) in a collection of 89 extended-spectrum beta-lactamase (ESBL)-producing isolates from different patients (77 pulsed-field gel electrophoresis clones, 12 ESBL types) than in non-ESBL E. coli (26%) strains (P = 0.03). Among urinary tract isolates, the frequency of hypermutation was 40% in ESBL versus 26% in non-ESBL isolates (P = 0.03).
Baquero
María-Rosario
MR
Department of Microbiology, Ramón y Cajal University Hospital, Madrid, Spain.
Galán
Juan Carlos
JC
del Carmen Turrientes
María
M
Cantón
Rafael
R
Coque
Teresa M
TM
Martínez
José Luis
JL
Baquero
Fernando
F
D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics*; D006801:Humans; D009154:Mutation; D001618:beta-Lactamases / Q000032:analysis*
D001618:beta-Lactamases