1AYE:
reference: The three-dimensional structure of human procarboxypeptidase A2. Deciphering the basis of the inhibition, activation and intrinsic activity of the zymogen., Garcia-Saez I, Reverter D, Vendrell J, Aviles FX, Coll M, EMBO J 1997 Dec 1;16(23):6906-13. PMID: 9384570

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).