New beta-lactamases: a paradigm for the rapid response of bacterial evolution in the clinical setting.
Production of beta-lactamases is one of the most common mechanisms of bacterial resistance to beta-lactam antibiotics. In the clinical setting, the introduction of new classes of beta-lactams has invariably been followed by the emergence of new beta-lactamases capable of degrading them, as a paradigmatic example of rapid bacterial evolution under a rapidly changing selective environment. The scope of this article is to provide an overview on the recent evolution of beta-lactamase-mediated resistance among bacterial pathogens. Focus is on the mechanisms of evolution and dissemination of enzymes of greater clinical impact, including the extended-spectrum beta-lactamases, the AmpC-type beta-lactamases and the carbapenemases, which are currently responsible for emerging resistance to the most recent and powerful beta-lactams (the expanded-spectrum cephalosporins and the carbapenems) among major Gram-negative pathogens such as Enterobacteriaceae, Pseudomonas aeruginosa and Acinetobacter.
Rossolini
Gian Maria
GM
University of Siena, Department of Molecular Biology, Section of Microbiology, Policlinico Santa Maria alle Scotte, Siena, Italy. rossolini@unisi.it
Docquier
Jean-Denis
JD
D001419:Bacteria / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D015780:Carbapenems / Q000494:pharmacology; D002511:Cephalosporins / Q000494:pharmacology; D019143:Evolution, Molecular; D009154:Mutation; D018440:beta-Lactam Resistance / Q000235:genetics*; D001618:beta-Lactamases / Q000235:genetics* / Q000378:metabolism
D001426:Bacterial Proteins; D015780:Carbapenems; D002511:Cephalosporins; C048795:AmpC beta-lactamases; D001618:beta-Lactamases