title: Integron-located oxa-32 gene cassette encoding an extended-spectrum variant of OXA-2 beta-lactamase from Pseudomonas aeruginosa.
abstract: 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.
authors.affiliation: Service de Bactériologie-Virologie, Hôpital de Bicêtre, Assistance Publique/Hôpitaux de Paris, Faculté de Médecine Paris-Sud, 94275 Le Kremlin-Bicêtre, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Poirel
authors.forename: Patrick
authors.initials: P
authors.lastname: Gerome
authors.forename: Christophe
authors.initials: C
authors.lastname: De Champs
authors.forename: Jean
authors.initials: J
authors.lastname: Stephanazzi
authors.forename: Thierry
authors.initials: T
authors.lastname: Naas
authors.forename: Patrice
authors.initials: P
authors.lastname: Nordmann
mesh_terms: 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*
chemical_list: D002511:Cephalosporins; D002442:Ceftazidime; D000123:Acetyltransferases; C056532:aminoglycoside N(6')-acetyltransferase; C039404:beta-lactamase OXA-2; D001618:beta-Lactamases; D002439:Cefotaxime