Preferential cleavage at the carboxyl of hydrophobic amino acids, but fails to cleave 15-Leu-|-Tyr-16, 16-Tyr-|-Leu-17 and 24-Phe-|-Phe-25 of insulin B chain. Activates trypsinogen, and degrades keratin. Monomer. O-glycosylated. Expressed both in W (white) and in O (opaque) cells of strain WO-1. Belongs to the peptidase A1 family.