title: beta-Lactamase-catalyzed hydrolysis of acyclic depsipeptides and acyl transfer to specific amino acid acceptors.
abstract: beta-Lactamases from all three classes, A, B, and C, catalyze the hydrolysis of specific acyclic depsipeptide (PhCH2CONHCR1R2CO2CHR3CO2H) analogs of acyl-D-alanyl-D-alanine peptides. The depsipeptides investigated, which are chemically as reactive toward nucleophiles as penicillins, are in general poor substrates, although differences between the classes of beta-lactamases have been observed: the order of effectiveness seems to be C greater than B greater than A. Certain class A and C beta-lactamases also catalyze phenylacetylglycyl transfer between phenylacetylglycyl depsipeptides and specific amino acid acceptors, a type of reaction hitherto identified more closely with D-alanyl-D-alanine transpeptidases than with beta-lactamases. Preliminary indications of an acyl-enzyme intermediate in these reactions have been obtained. These results support the suggestion [Tipper, D.J. and Strominger, J.L. (1965) Proc. Natl. Acad. Sci. USA 54, 1133-1141] that beta-lactamases are evolutionary descendants of bacterial cell wall D-alanyl-D-alanine transpeptidases.
mesh_terms: D000215:Acylation; D001409:Bacillus cereus / Q000201:enzymology; D004754:Enterobacter / Q000201:enzymology; D004926:Escherichia coli / Q000201:enzymology; D006868:Hydrolysis; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D009842:Oligopeptides; D013211:Staphylococcus aureus / Q000201:enzymology; D013379:Substrate Specificity; D001618:beta-Lactamases / Q000378:metabolism*
chemical_list: D009842:Oligopeptides; D001618:beta-Lactamases