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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.

SUBMITTER: Poirel L

PROVIDER: S-EPMC127075 | biostudies-literature | 2002 Feb

REPOSITORIES: biostudies-literature

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Integron-located oxa-32 gene cassette encoding an extended-spectrum variant of OXA-2 beta-lactamase from Pseudomonas aeruginosa.

Poirel Laurent L Gerome Patrick P De Champs Christophe C Stephanazzi Jean J Naas Thierry T Nordmann Patrice P

Antimicrobial agents and chemotherapy 20020201 2

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. ...[more]

PMID: 11796380

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OXA-28, an extended-spectrum variant of OXA-10 beta-lactamase from Pseudomonas aeruginosa and its plasmid- and integron-located gene.

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