2A1D:
reference: Structural basis for reduced staphylocoagulase-mediated bovine prothrombin activation., Friedrich R, Panizzi P, Kawabata S, Bode W, Bock PE, Fuentes-Prior P, J Biol Chem. 2006 Jan 13;281(2):1188-95. Epub 2005 Oct 17. PMID: 16230338

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