May be involved in the proteolytic inactivation of enkephalins and neurotensin in some brain areas. May convert inactive angiotensin I into the biologically active angiotensin II. Releases a C-terminal amino acid, with preference for large hydrophobic C-terminal amino acids and shows only very weak activity toward small amino acids and histidine. Binds 1 zinc ion per subunit. In brain, highly expressed in the olfactory bulb with lower levels in other regions including cerebral cortex, hippocampus, hypothalamus, striatum and medulla. Within the olfactory bulb, highest levels occur in the mitral and granular layers with lower levels in the internal and external plexiform layers. Moderate levels are found in the epididymis with low levels in colon and spleen. Not detected in adrenal, liver, lung, ovary or testis. At embryonic day 14.5, enriched in eye, ear, osteoblasts, stomach, skin, dorsal root ganglia and throughout the CNS. Belongs to the peptidase M14 family.