5IOS:
reference: Deprotonations in the Reaction of Flavin-Dependent Thymidylate Synthase., Stull FW, Bernard SM, Sapra A, Smith JL, Zuiderweg ER, Palfey BA, Biochemistry. 2016 Jun 14;55(23):3261-9. doi: 10.1021/acs.biochem.6b00510. Epub, 2016 Jun 2. PMID: 27214228

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