3S69:
reference: Structure of saxthrombin, a thrombin-like enzyme from Gloydius saxatilis., Huang K, Zhao W, Gao Y, Wei W, Teng M, Niu L, Acta Crystallogr Sect F Struct Biol Cryst Commun. 2011 Aug 1;67(Pt 8):862-5. Epub, 2011 Jul 13. PMID: 21821882

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