4EJL:
reference: Small Molecule Regulation of Protein Conformation by Binding in the Flap of HIV Protease., Tiefenbrunn T, Forli S, Baksh MM, Chang MW, Happer M, Lin YC, Perryman AL, Rhee JK, Torbett BE, Olson AJ, Elder JH, Finn MG, Stout CD, ACS Chem Biol. 2013 Mar 29. PMID: 23540839

This OCA Structure page
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