3F6U: Crystal Structure Of Human Activated Protein C (Apc) Complex Ppack
reference: Thermodynamic linkage between the S1 site, the Na+ site, and the Ca2+ site in the protease domain of human activated protein C (APC). Sodium ion in the APC crystal structure is coordinated to four carbonyl groups from two separate loops., Schmidt AE, Padmanabhan K, Underwood MC, Bode W, Mather T, Bajaj SP, J Biol Chem. 2002 Aug 9;277(32):28987-95. Epub 2002 May 23. PMID: 12029084

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