4LP9:
reference: The structure of endothiapepsin complexed with a Phe-Tyr reduced-bond inhibitor at 1.35 A resolution., Guo J, Cooper JB, Wood SP, Acta Crystallogr F Struct Biol Commun. 2014 Jan;70(Pt 1):30-3. doi:, 10.1107/S2053230X13032974. Epub 2013 Dec 24. PMID: 24419612

This OCA Structure page
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