Venom protein that cleaves N-terminal acidic residues from peptides with high potency in presence of calcium (PubMed:20706583). It may have several roles in venom including alteration of blood pressure by cleaving circulating angiotensin-2, general degradation of host tissue, increase of permeability to other venom components, and/or processing of other toxins in the venom (By similarity). Release of N-terminal glutamate (and to a lesser extent aspartate) from a peptide. Binds 1 zinc ion per subunit. Substrate specificity is modulated by calcium which enhances the enzymatic activity for cleavage of acidic residues while reducing its activity with neutral and basic residues (PubMed:20706583). Hydrolytic activity is inhibited by the aminopeptidase inhibitor (Leu and acidic inhibitor) amastatin, but not by bestatin (aminopeptidase inhibitor Leu inhibitor), leupeptin, pepstatin A and PMSF (PubMed:20706583). Its hydrolytic activity is also strongly reduced by zinc ions, with a complete inhibition at 0.5 mM, and moderately inhibited by cobalt and cupper ions (PubMed:20706583). Homodimer; disulfide-linked. Found in the venom as transmembrane proteins in exosome-like vesicles. N-glycosylated. Glycosylation counts for an increased mass of about 32% of the protein mass (about 48 kDa). Belongs to the peptidase M1 family.