Cleaves and degrades bioactive peptides, including angiotensin, Leu-enkephalin and Met-enkephalin (By similarity). Also cleaves Arg-Arg-beta-naphthylamide. Release of an N-terminal dipeptide from a peptide comprising four or more residues, with broad specificity. Also acts on dipeptidyl 2-naphthylamides. Binds 1 zinc ion per subunit. Inhibited by spinorphin, an opioid peptide derived from hemoglobin. Optimum pH is 9.0. Belongs to the peptidase M49 family.