1FFV:
reference: The effect of intracellular molybdenum in Hydrogenophaga pseudoflava on the crystallographic structure of the seleno-molybdo-iron-sulfur flavoenzyme carbon monoxide dehydrogenase., Hanzelmann P, Dobbek H, Gremer L, Huber R, Meyer O, J Mol Biol 2000 Sep 1;301(5):1221-35. PMID: 10966817

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