Accumulation of acyl-enzyme in DD-peptidase-catalysed reactions with analogues of peptide substrates

Abstract

Thioester substrates can be used to study the hydrolysis and transfer reactions catalysed by, β-lactamases and DD-peptidases. With the latter enzymes, accumulation of the acyl-enzyme can be detected directly. The efficiency of various amines as acceptor substrates was in excellent agreement with previous results obtained with peptide substrates of the DD-peptidases. Thc results indicated the presence of a specific binding site for the acceptor substrates. Although most of the results agreed well with a simple partition model, more elaborate hypotheses will be needed to account for all the data presented.