1FXR:
reference: Crystal structure of the ferredoxin I from Desulfovibrio africanus at 2.3 A resolution., Sery A, Housset D, Serre L, Bonicel J, Hatchikian C, Frey M, Roth M, Biochemistry 1994 Dec 27;33(51):15408-17. PMID: 7803404

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