2XYG:
reference: In silico identification and crystal structure validation of caspase-3 inhibitors without a P1 aspartic acid moiety., Ganesan R, Jelakovic S, Mittl PR, Caflisch A, Grutter MG, Acta Crystallogr Sect F Struct Biol Cryst Commun. 2011 Aug 1;67(Pt, 8):842-50. Epub 2011 Jul 13. PMID: 21821879

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