Hydrolysis of alpha(s1)- and beta-casein-derived peptides with a broad specificity aminopeptidase and proline specific aminopeptidases from Lactococcus lactis subsp. cremoris AM2

Aminopeptidase hydrolysis of alpha(s1)- and beta-casein-derived synthetic p eptides containing non-consecutive and consecutive proline residues was cha racterised, Aminopeptidase P (Pep P) (EC 3.4.11.9) or post-proline dipeptid yl aminopeptidase (PPDA) (EC 3.4.14.5) along,vith lysine-paranitroanilide h ydrolase (KpNA-H) (EC 3.4.11.1) activities are required in the degradation of peptides containing non-consecutive proline residues. However, both Pep P and PPDA along with KpNA-H are required for hydrolysis of peptides contai ning consecutive proline residues. The results demonstrate the mechanism by which combinations of purified general and proline specific aminopeptidase s from Lactococcus lactis subsp, cremoris AM2 hydrolyse peptides containing proline residues. (C) 1999 Federation of European Biochemical Societies.