Aminopeptidases in webbing clothes moth larvae. Properties and specificities of the enzymes of intermediate electrophoretic mobility.

The major group of aminopeptidases (EC 3.4.11.-) of intermediate electrophoretic mobility, from Tineola bisselliella larvae, hav been fractionated into six bands by preparative polyacrylamide gel electrophoresis and the properties of these fractions investigated. They resemble each other in their pH optima of 8.2, their molecular weight of 240 000, their responses to various active site inhibitors and metal cations, and their specificities towards seventeen L-amino-acyl-beta-naphthylamide substrates. The derivatives of methionine, leucine, alanine, lysine, arginine and glutamic acid were those most rapidly hydrolysed. They appear to be true aminopeptidases hydrolysing amino acid amides, dipeptides and oligopeptides from the N-terminal end.