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OXA-58, a novel class D {beta}-lactamase involved in resistance to carbapenems in Acinetobacter baumannii.

ABSTRACT: A carbapenem-resistant Acinetobacter baumannii strain was isolated in Toulouse, France, in 2003. Cloning and expression in Escherichia coli identified the carbapenem-hydrolyzing beta-lactamase OXA-58, which is weakly related (less than 50% amino acid identity) to other oxacillinases. It hydrolyzed penicillins, oxacillin, and imipenem but not expanded-spectrum cephalosporins. The bla(OXA-58) gene was located on a ca. 30-kb non-self-transferable plasmid. After electrotransformation in the A. baumannii CIP7010(T) reference strain, it conferred reduced susceptibility to carbapenems. The bla(OXA-58) gene was bracketed by two novel ISAba3-like insertion elements. This study describes a newly characterized beta-lactamase that may contribute to carbapenem resistance in A. baumannii.

SUBMITTER: Poirel L

PROVIDER: S-EPMC538857 | biostudies-literature | 2005 Jan

REPOSITORIES: biostudies-literature

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OXA-58, a novel class D {beta}-lactamase involved in resistance to carbapenems in Acinetobacter baumannii.

Poirel Laurent L Marqué Sophie S Héritier Claire C Segonds Christine C Chabanon Gérard G Nordmann Patrice P

Antimicrobial agents and chemotherapy 20050101 1

A carbapenem-resistant Acinetobacter baumannii strain was isolated in Toulouse, France, in 2003. Cloning and expression in Escherichia coli identified the carbapenem-hydrolyzing beta-lactamase OXA-58, which is weakly related (less than 50% amino acid identity) to other oxacillinases. It hydrolyzed penicillins, oxacillin, and imipenem but not expanded-spectrum cephalosporins. The bla(OXA-58) gene was located on a ca. 30-kb non-self-transferable plasmid. After electrotransformation in the A. bauma ...[more]

PMID: 15616297

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