3FST:
reference: Functional role for the conformationally mobile phenylalanine 223 in the reaction of methylenetetrahydrofolate reductase from Escherichia coli., Lee MN, Takawira D, Nikolova AP, Ballou DP, Furtado VC, Phung NL, Still BR, Thorstad MK, Tanner JJ, Trimmer EE, Biochemistry. 2009 Aug 18;48(32):7673-85. PMID: 19610625

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