1Q6L:
reference: Structural evidence for a 1,2-enediolate intermediate in the reaction catalyzed by 3-keto-L-gulonate 6-phosphate decarboxylase, a member of the orotidine 5'-monophosphate decarboxylase suprafamily., Wise EL, Yew WS, Gerlt JA, Rayment I, Biochemistry 2003 Oct 28;42(42):12133-42. PMID: 14567674

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