1R8O:
reference: Three-dimensional structure of an unusual Kunitz (STI) type trypsin inhibitor from Copaifera langsdorffii., Krauchenco S, Nagem RA, da Silva JA, Marangoni S, Polikarpov I, Biochimie 2004 Mar;86(3):167-72. PMID: 15134830

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