First report of CTX-M-9 in a clinical isolate of Enterobacter cloacae in a Tunisian hospital.
β-lactamases are one of several mechanisms of bacterial resistance to β-lactam antibiotics. The aim of this study was to analyze the resistance to extended-spectrum cephalosporins of a multidrug-resistant isolate of Enterobacter cloacae, BF5011. This strain was isolated from a stool culture, during the nosocomials infections occurring in the intensive care unit of the Military Hospital of Tunis in 2005. Analysis of E. cloacae BF5011 by double-disk synergy test yielded a positive result suggesting the production of extended-spectrum-β-lactamases. Cell sonicate of this isolate is very active against cefotaxime and showed a specific activity (AS) of 7,54 U/mg for the same antibiotic. This activity was inhibited by the sulbactam and the clavulanic acid. By polymerase chain reaction and sequencing, the isolate was found to produce extended-spectrum-β-lactamase, CTX-M-9. The bla(CTX-M-9) gene was transferred from E. cloacae by conjugation. Isoelectric focusing method revealed one band with a pI of about 8. This is the first report of CTX-M-9 in Tunisia.
Bourouis
A
A
Laboratoire de Biochimie & Technobiologie, Faculté des Sciences de Tunis, Université Elmanar II, Tunis, Tunisia. boursaamel@yahoo.fr
Dubois
V
V
Coulange
L
L
André
C
C
Bejhadj
C
C
Ben Moussa
M
M
Quentin
C
C
Belhadj
O
O
D000900:Anti-Bacterial Agents / Q000378:metabolism; D002439:Cefotaxime / Q000378:metabolism; D024881:Drug Resistance, Bacterial / Q000235:genetics; D018432:Drug Resistance, Multiple / Q000235:genetics; D016972:Enterobacter cloacae / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D005243:Feces / Q000382:microbiology; D006801:Humans; D008826:Microbial Sensitivity Tests; D018440:beta-Lactam Resistance / Q000235:genetics; D001618:beta-Lactamases / Q000737:chemistry / Q000378:metabolism*
D000900:Anti-Bacterial Agents; D001618:beta-Lactamases; D002439:Cefotaxime