3C9X:
reference: Statistical Coupling Analysis of Aspartic Proteinases Based on Crystal Structures of the Trichoderma reesei Enzyme and Its Complex with Pepstatin A., Nascimento AS, Krauchenco S, Golubev AM, Gustchina A, Wlodawer A, Polikarpov I, J Mol Biol. 2008 Jul 22. PMID: 18675276

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