title: 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.
authors.affiliation: Service de Bactériologie-Virologie, Hôpital de Bicêtre, 78 rue du Général Leclerc, 94275 Le Kremlin-Bicêtre Cedex, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Poirel
authors.forename: Sophie
authors.initials: S
authors.lastname: Marqué
authors.forename: Claire
authors.initials: C
authors.lastname: Héritier
authors.forename: Christine
authors.initials: C
authors.lastname: Segonds
authors.forename: Gérard
authors.initials: G
authors.lastname: Chabanon
authors.forename: Patrice
authors.initials: P
authors.lastname: Nordmann
mesh_terms: D040981:Acinetobacter baumannii / Q000187:drug effects* / Q000201:enzymology; D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001483:Base Sequence; D015780:Carbapenems / Q000494:pharmacology*; D006801:Humans; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D017422:Sequence Analysis, DNA; D018440:beta-Lactam Resistance; D001618:beta-Lactamases / Q000737:chemistry / Q000145:classification / Q000235:genetics / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems; D001618:beta-Lactamases; C108449:oxacillinase