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Carbapenem-hydrolyzing GES-type extended-spectrum beta-lactamase in Acinetobacter baumannii.

ABSTRACT: Acinetobacter baumannii isolate AP was recovered from a bronchial lavage of a patient hospitalized in Paris, France. A. baumannii AP was resistant to all ?-lactams, including carbapenems, and produced the extended-spectrum ?-lactamase (ESBL) GES-14, which differs from GES-1 by two substitutions, Gly170Ser and Gly243Ala. Cloning of the bla(GES-14) gene followed by its expression in Escherichia coli showed that GES-14 compromised significantly the efficacy of all ?-lactams, including cephalosporins, aztreonam, and carbapenems. The carbapenemase activity of purified GES-14 was confirmed by kinetic studies. The bla(GES-14) gene was located into a class 1 integron structure and located onto a ca. 95-kb self-transferable plasmid. This study identified a very broad-spectrum ?-lactamase in A. baumannii.

SUBMITTER: Bonnin RA

PROVIDER: S-EPMC3019676 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature

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Carbapenem-hydrolyzing GES-type extended-spectrum beta-lactamase in Acinetobacter baumannii.

Bonnin Rémy A RA Nordmann Patrice P Potron Anaïs A Lecuyer Hervé H Zahar Jean-Ralph JR Poirel Laurent L

Antimicrobial agents and chemotherapy 20101018 1

Acinetobacter baumannii isolate AP was recovered from a bronchial lavage of a patient hospitalized in Paris, France. A. baumannii AP was resistant to all β-lactams, including carbapenems, and produced the extended-spectrum β-lactamase (ESBL) GES-14, which differs from GES-1 by two substitutions, Gly170Ser and Gly243Ala. Cloning of the bla(GES-14) gene followed by its expression in Escherichia coli showed that GES-14 compromised significantly the efficacy of all β-lactams, including cephalosporin ...[more]

PMID: 20956589

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