1ETS:
reference: Refined 2.3 A X-ray crystal structure of bovine thrombin complexes formed with the benzamidine and arginine-based thrombin inhibitors NAPAP, 4-TAPAP and MQPA. A starting point for improving antithrombotics., Brandstetter H, Turk D, Hoeffken HW, Grosse D, Sturzebecher J, Martin PD, Edwards BF, Bode W, J Mol Biol 1992 Aug 20;226(4):1085-99. PMID: 1518046

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