1CKU:
reference: Ab initio solution and refinement of two high-potential iron protein structures at atomic resolution., Parisini E, Capozzi F, Lubini P, Lamzin V, Luchinat C, Sheldrick GM, Acta Crystallogr D Biol Crystallogr 1999 Nov;55(11):1773-84. PMID: 10531472

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