Releases C-terminal Arg and Lys from polypeptides. Binds 2 Zn(2+) ions per subunit. Optimum pH is 6.0-6.5. Highly expressed in placenta, pancreas and hepatoma cells. Lower levels found in skeletal muscle, heart and colon carcinoma and melanoma cell lines. There are 3 carboxypeptidase-like domains. Only the first two domains seem to have kept a catalytic activity. Belongs to the peptidase M14 family.