1NBB:
reference: Concerted movement of side chains in the haem vicinity observed on ligand binding in cytochrome c' from rhodobacter capsulatus., Tahirov TH, Misaki S, Meyer TE, Cusanovich MA, Higuchi Y, Yasuoka N, Nat Struct Biol 1996 May;3(5):459-64. PMID: 8612077

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