2CND:
reference: Structural studies on corn nitrate reductase: refined structure of the cytochrome b reductase fragment at 2.5 A, its ADP complex and an active-site mutant and modeling of the cytochrome b domain., Lu G, Lindqvist Y, Schneider G, Dwivedi U, Campbell W, J Mol Biol 1995 May 19;248(5):931-48. PMID: 7760334

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