Integron-located oxa-32 gene cassette encoding an extended-spectrum variant of OXA-2 beta-lactamase from Pseudomonas aeruginosa.
Pseudomonas aeruginosa clinical isolate CY-1, which was resistant to ceftazidime, harbored a conjugative ca. 250-kb plasmid that contained a class 1 integron with two gene cassettes encoding OXA-32, an OXA-2- type beta-lactamase, and the aminoglycoside acetyltransferase AAC(6')Ib(9). OXA-32 differed from OXA-2 by an Leu169Ile amino acid substitution (class D numbering). Site-directed mutagenesis established that Ile169 is responsible for resistance to ceftazidime but not to cefotaxime.
Poirel
Laurent
L
Service de Bactériologie-Virologie, Hôpital de Bicêtre, Assistance Publique/Hôpitaux de Paris, Faculté de Médecine Paris-Sud, 94275 Le Kremlin-Bicêtre, France.
Gerome
Patrick
P
De Champs
Christophe
C
Stephanazzi
Jean
J
Naas
Thierry
T
Nordmann
Patrice
P
D000123:Acetyltransferases / Q000378:metabolism; D000595:Amino Acid Sequence; D002439:Cefotaxime / Q000494:pharmacology; D002442:Ceftazidime / Q000494:pharmacology; D002511:Cephalosporins / Q000494:pharmacology; D024881:Drug Resistance, Bacterial / Q000502:physiology; D006801:Humans; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D001618:beta-Lactamases / Q000235:genetics*
D002511:Cephalosporins; D002442:Ceftazidime; D000123:Acetyltransferases; C056532:aminoglycoside N(6')-acetyltransferase; C039404:beta-lactamase OXA-2; D001618:beta-Lactamases; D002439:Cefotaxime