OXA-235, a novel class D β-lactamase involved in resistance to carbapenems in Acinetobacter baumannii.

ABSTRACT: We investigated the mechanism of carbapenem resistance in 10 Acinetobacter baumannii strains isolated from the United States and Mexico between 2005 and 2009. The detection of known metallo-β-lactamase or carbapenem-hydrolyzing oxacillinase (OXA) genes by PCR was negative. The presence of plasmid-encoded carbapenem resistance genes was investigated by transformation of A. baumannii ATCC 17978. Shotgun cloning experiments and sequencing were performed, followed by the expression of a novel β-lactamase in A. baumannii. Three novel OXA enzymes were identified, OXA-235 in 8 isolates and the amino acid variants OXA-236 (Glu173-Val) and OXA-237 (Asp208-Gly) in 1 isolate each. The deduced amino acid sequences shared 85% identity with OXA-134, 54% to 57% identities with the acquired OXA-23, OXA-24

SUBMITTER: Higgins PG 

PROVIDER: S-EPMC3632948 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature