2AZN:
reference: Biosynthesis of riboflavin: structure and properties of 2,5-diamino-6-ribosylamino-4(3H)-pyrimidinone 5'-phosphate reductase of Methanocaldococcus jannaschii., Chatwell L, Krojer T, Fidler A, Romisch W, Eisenreich W, Bacher A, Huber R, Fischer M, J Mol Biol. 2006 Jun 23;359(5):1334-51. Epub 2006 May 6. PMID: 16730025

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