6MV4:
reference: Sodium-site in serine protease domain of human coagulation factor IXa: evidence from the crystal structure and molecular dynamics simulations study., Vadivel K, Schreuder HA, Liesum A, Schmidt AE, Goldsmith G, Bajaj SP, J Thromb Haemost. 2019 Feb 6. doi: 10.1111/jth.14401. PMID: 30725510

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