title: beta-Lactamases of increasing clinical importance.
abstract: Resistance to b-lactam-containing antimicrobial agents continues to increase, frequently due to the presence of b-lactamases in Gram-negative bacteria. Over the past twenty-five years broad-spectrum enzymes such as TEM- and SHV-variants and the metallo-b-lactamases have become more prolific. As a result of the ability of plasmids to continue to acquire additional resistance determinants, many of the b-lactamase-producing Gram-negative pathogens have become multi-drug resistant. In combination with decreased permeability, the organisms can become virtually untreatable with current therapies. The major groups of b-lactamases that pose the most serious therapeutic problems include the extended-spectrum b-lactamases, the plasmid-mediated cephalosporinases, the inhibitor-resistant TEM- or SHV-derived b-lactamases and the carbapenem-hydrolyzing b-lactamases. Those enzymes that can be transferred on mobile elements are the most serious of the newer b-lactamases, and include enzymes in each of the four groups outlined above.
authors.affiliation: The R. W. Johnson Pharmaceutical Research Institute, Raritan, NJ 08869, USA. kbush@prius.jnj.com
authors.forename: K
authors.initials: K
authors.lastname: Bush
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use; D018432:Drug Resistance, Multiple / Q000502:physiology*; D006090:Gram-Negative Bacteria / Q000187:drug effects / Q000201:enzymology; D006801:Humans; D018440:beta-Lactam Resistance / Q000502:physiology*; D065093:beta-Lactamase Inhibitors; D001618:beta-Lactamases / Q000145:classification / Q000378:metabolism*; D047090:beta-Lactams
chemical_list: D000900:Anti-Bacterial Agents; D065093:beta-Lactamase Inhibitors; D047090:beta-Lactams; D001618:beta-Lactamases