title: [Identification and classification of beta-lactamases in clinical isolates of bacteria].
abstract: Emergence of bacterial resistance has rendered ineffective a number of previously valuable antibiotic treatments and now threatens the effectiveness of others. beta-Lactam resistance is no longer predominantly a hospital-treated problem; it has now become an important issue in community medicine. More than 100-beta-lactamases have been identified and classified according to their structure, substrate specificity, and whether they are chromosomal or plasmid-mediated. beta-Lactamase production is rare among Gram-positive pathogens, important exceptions being Staphylococcus aureus and Enterococcus faecalis. By contrast, many Gram-negative pathogens are beta-lactamase-positive; inducible and/or hyper-productive strains are particularly challenging in the clinical setting. Surveillance programs have shown that, in general, beta-lactam resistance is on the increase, and that the plasmid-mediated beta-lactamase have developed rapidly over past decade such as ESBLs and carbapenemases.
authors.affiliation: Department of Microbiology, School of Medicine and Environmental Infection Diseases, Graduate School of Medical Science, Kitasato University.
authors.forename: Matsuhisa
authors.initials: M
authors.lastname: Inoue
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Nakano
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Hosaka
authors.forename: Naohiro
authors.initials: N
authors.lastname: Okitsu
authors.forename: Kenichi
authors.initials: K
authors.lastname: Kaneko
authors.forename: Yoko
authors.initials: Y
authors.lastname: Komatsu
authors.forename: Hidero
authors.initials: H
authors.lastname: Kitasato
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Okamoto
mesh_terms: D006090:Gram-Negative Bacteria / Q000201:enzymology / Q000302:isolation & purification; D006094:Gram-Positive Bacteria / Q000201:enzymology / Q000302:isolation & purification; D008826:Microbial Sensitivity Tests; D018440:beta-Lactam Resistance / Q000235:genetics; D001618:beta-Lactamases / Q000145:classification / Q000302:isolation & purification*
chemical_list: D001618:beta-Lactamases