2XDQ:
reference: Crystal structure of the nitrogenase-like dark operative protochlorophyllide oxidoreductase catalytic complex (ChlN/ChlB)2., Brocker MJ, Schomburg S, Heinz DW, Jahn D, Schubert WD, Moser J, J Biol Chem. 2010 Aug 27;285(35):27336-45. Epub 2010 Jun 17. PMID: 20558746

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