1F2C:
reference: A target within the target: probing cruzain's P1' site to define structural determinants for the Chagas' disease protease., Brinen LS, Hansell E, Cheng J, Roush WR, McKerrow JH, Fletterick RJ, Structure Fold Des 2000 Aug 15;8(8):831-40. PMID: 10997902

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