6NUL:
reference: Control of oxidation-reduction potentials in flavodoxin from Clostridium beijerinckii: the role of conformation changes., Ludwig ML, Pattridge KA, Metzger AL, Dixon MM, Eren M, Feng Y, Swenson RP, Biochemistry 1997 Feb 11;36(6):1259-80. PMID: 9063874

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