title: Role of penicillin-binding proteins in the initiation of the AmpC beta-lactamase expression in Enterobacter cloacae.
abstract: Penicillin-binding proteins (PBPs) are involved in the regulation of beta-lactamase expression by determining the level of anhydromuramylpeptides in the periplasmatic space. It was hypothesized that one or more PBPs act as a sensor in the beta-lactamase induction pathway. We have performed induction studies with Escherichia coli mutants lacking one to four PBPs with DD-carboxypeptidase activity. Therefore, we conclude that a strong beta-lactamase inducer must inhibit all DD-carboxypeptidases as well as the essential PBPs 1a, 1b, and/or 2.
authors.affiliation: Pharmazeutische Mikrobiologie, University of Bonn, 53115 Bonn, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Pfeifle
authors.forename: E
authors.initials: E
authors.lastname: Janas
authors.forename: B
authors.initials: B
authors.lastname: Wiedemann
mesh_terms: D001426:Bacterial Proteins; D002268:Carboxypeptidases / Q000037:antagonists & inhibitors / Q000502:physiology; D002352:Carrier Proteins / Q000502:physiology*; D016972:Enterobacter cloacae / Q000187:drug effects / Q000201:enzymology*; D004790:Enzyme Induction; D006602:Hexosyltransferases; D008826:Microbial Sensitivity Tests; D002267:Muramoylpentapeptide Carboxypeptidase / Q000502:physiology*; D046915:Penicillin-Binding Proteins; D010458:Peptidyl Transferases; D001618:beta-Lactamases / Q000096:biosynthesis*
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D046915:Penicillin-Binding Proteins; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D002268:Carboxypeptidases; D002267:Muramoylpentapeptide Carboxypeptidase; C048795:AmpC beta-lactamases; D001618:beta-Lactamases