Genetic and biochemical characterization of a novel metallo-β-lactamase, TMB-1, from an Achromobacter xylosoxidans strain isolated in Tripoli, Libya.

Cardiff University, Cardiff, United Kingdom.
Antimicrobial Agents and Chemotherapy (Impact Factor: 4.57). 01/2012; 56(5):2241-5. DOI: 10.1128/AAC.05640-11
Source: PubMed

ABSTRACT An Achromobacter xylosoxidans strain from the Tripoli central hospital produced a unique metallo-β-lactamase, designated TMB-1, which is related to DIM-1 (62%) and GIM-1 (51%). bla(TMB-1) was embedded in a class 1 integron and located on the chromosome. The TMB-1 β-lactamase has lower k(cat) values than both DIM-1 and GIM-1 with cephalosporins and carbapenems. The K(m) values were more similar to those of GIM-1 than those of DIM-1, with the overall k(cat)/K(m) values being lower than those for GIM-1 and DIM-1.

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