title: Emergence of resistance in gram-negative bacteria: a risk of broad-spectrum beta-lactam use.
abstract: A number of new beta-lactam antibiotics have been developed to overcome bacterial resistance to older agents. Such resistance usually is caused by plasmid-mediated, constituently produced beta-lactamases. Second- and third-generation cephalosporins, ureidopenicillins, acylamino penicillins, and monobactams generally are resistant to hydrolysis by these enzymes. However, inducible beta-lactamases may confer resistance to these antibiotics. This induction may occur spontaneously or in response to cefoxitin or other beta-lactam agents. The mechanisms by which inducible enzymes produce this resistance are reviewed and implications for the prophylactic and therapeutic use of newer beta-lactams are considered.
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000037:antagonists & inhibitors / Q000378:metabolism / Q000494:pharmacology* / Q000627:therapeutic use; D001426:Bacterial Proteins; D002352:Carrier Proteins / Q000378:metabolism; D004352:Drug Resistance, Microbial; D004790:Enzyme Induction; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D006602:Hexosyltransferases; D006801:Humans; D006868:Hydrolysis; D051379:Mice; D002267:Muramoylpentapeptide Carboxypeptidase / Q000378:metabolism; D046915:Penicillin-Binding Proteins; D010458:Peptidyl Transferases; D012306:Risk; D001618:beta-Lactamases / Q000096:biosynthesis; D047090:beta-Lactams
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D002352:Carrier Proteins; D046915:Penicillin-Binding Proteins; D047090:beta-Lactams; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D002267:Muramoylpentapeptide Carboxypeptidase; D001618:beta-Lactamases