Membrane-bound metalloprotease which catalyzes the removal of a penultimate prolyl residue from the N-termini of peptides, such as Arg-Pro-Pro. May play a role in the metabolism of the vasodilator bradykinin. Release of any N-terminal amino acid, including proline, that is linked to proline, even from a dipeptide or tripeptide. Homotrimer. Strongly expressed in small intestine, heart and lung. Also detected in testis, skeletal muscle, spleen, liver, kidney, brain, uterus, eye, lymph node, thymus, stomach, prostate and bone marrow. Expressed in embryos from 7 days onwards, with highest expression at 15 days. N-glycosylated. Belongs to the peptidase M24B family.