4GSO:
reference: Crystal structure of Jararacussin-I: The highly negatively charged catalytic interface contributes to macromolecular selectivity in snake venom thrombin-like enzymes., Ullah A, Souza TC, Zanphorlin LM, Mariutti RB, Santana VS, Murakami MT, Arni RK, Protein Sci. 2012 Nov 8. doi: 10.1002/pro.2189. PMID: 23139169

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