Exopeptidase that catalyzes the removal of dipeptide units (NH2-P2-P1- or -P1'-P2'-COOH) from the free amino or carboxy termini. Prefers substrates composed of bulky, hydrophobic amino acids at P1 and P1' positions. Has endopeptidase activity on N-terminally blocked peptide derivatives which contain aromatic amino acid residue at the P1 position. Exopeptidase activity is much higher than its endopeptidase activity. Strongly inhibited by the serine protease inhibitor diisopropyl fluorophosphate (DFP), chymostatin, leupeptin, 0.5 mM ZnCl(2), 10 mM o-phenanthlorine and N-tosyl-L-phenyl-alanyl chloromethyl ketone (TPCK), but not by N-tosyl-L-lysyl chloromethyl ketone (TLCK). Activity is not affected significantly by iodoacetate (IAA), L-trans-epoxysuccinyl-leucylamido(4-guanido)butane (E64), pepstatin A and phenylmethanesulfonyl fluoride (PMSF). Activity is stimulated by addition of 0.5 mM CaCl(2), 10 mM EDTA and N-ethylmaleimide (NEM). Optimum pH is 8.5 to 9.0 for the hydrolysis of Gly-Phe-pNA. Optimum temperature is between 35 and 40 degrees Celsius for the hydrolysis of Gly-Phe-pNA. Stable at a temperature below 20 degrees Celsius for 30 minutes. Monomer. Belongs to the peptidase S9C family.