8.A.32.1.4
Pro-gastricsin, PGC of 388 aas.  It shows a more restricted substrate specificity than pepsin A, but shows preferential cleavage at Tyr-|-Xaa bonds (Hassan et al. 2010).  It is a member of the aspartic protease family, including pepsin and chymosin (Richter et al. 1998). It is involved in production of pro-antimicrobial substances in seminal plasma. The crystal structure shows that it is quite similar to that of porcine pepsinogen. The tertiary structure of PGC is bilobal with a large active-site cleft between the lobes. Two aspartyl residues in the center of the cleft, namely Asp32 and Asp215, function as catalytic residues (Hassan et al. 2010).