Reaction of Dipeptidylpeptidase IV with Substrate-Analogous Azapeptides

Abstract

The reaction of dipeptidyl peptidase IV (EC 3.4.14.5.) with azapeptide substrates containing azaalanine or azaproline in the P₁-position was investigaled. Accumulation of a fairly stable acyl-enzyme could be shown for ester substrates. Ala-AzaPro-pNA is a very poor substrate of DP IV and does not accumulate an acyl-enzyme. DP IV does not react with active-site titrants for trypsin-like serine proteases.