1UVT:
reference: Enzyme flexibility, solvent and 'weak' interactions characterize thrombin-ligand interactions: implications for drug design., Engh RA, Brandstetter H, Sucher G, Eichinger A, Baumann U, Bode W, Huber R, Poll T, Rudolph R, von der Saal W, Structure 1996 Nov 15;4(11):1353-62. PMID: 8939759

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