Open AccessOXA-163, an OXA-48-Related Class D β-Lactamase with Extended Activity Toward Expanded-Spectrum Cephalosporins
Author(s) -
Laurent Poirel,
Mariana Castanheira,
Amélie Carrër,
Carla Parada Rodriguez,
Ronald N. Jones,
Jorgelina Smayevsky,
Patrice Nordmann
Publication year - 2011
Publication title -
antimicrobial agents and chemotherapy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.07
H-Index - 259
eISSN - 1070-6283
pISSN - 0066-4804
DOI - 10.1128/aac.00022-11
Subject(s) - enterobacter cloacae , cefotaxime , cephalosporin , klebsiella pneumoniae , ceftazidime , biology , microbiology and biotechnology , plasmid , context (archaeology) , enterobacteriaceae , cefoxitin , carbapenem , genetics , beta lactamase , gene , antibiotics , bacteria , escherichia coli , pseudomonas aeruginosa , paleontology , staphylococcus aureus
Twobla OXA-48 -like-positive isolates (Klebsiella pneumoniae andEnterobacter cloacae ) were recovered in Argentina in 2008 as part of a large-scale survey focused on multidrug resistance inEnterobacteriaceae . In both cases, sequencing identified β-lactamase OXA-163, differing from OXA-48 by a single amino substitution and a 4-amino-acid deletion. OXA-163 hydrolyzed penicillins, ceftazidime, and cefotaxime, whereas OXA-48 did not. However, OXA-163 had a much lower ability to hydrolyze carbapenems than OXA-48, therefore barely being considered a carbapenemase. In both isolates, thebla OXA-163 gene was located on plasmids that differed in structure and size. However, a detailed genetic analysis revealed a similar genetic context in those isolates, with thebla OXA-163 gene being bracketed by novel transposase genes, making this genetic environment different from that reported for thebla OXA-48 gene. This study identified the first class D β-lactamase compromising both extended-spectrum cephalosporin and carbapenem activities.