Fig. 1

Biosynthetic pathway of 5-MTHF in E. coli. DHF, dihydrofolate. THF, tetrahydrofolate. CH₂-THF, 5,10-methylenetetrahydrofolate. 5-MTHF, 5-methyltetrahydrofolate. DHFR, dihydrofolate reductase. GlyA, serine hydroxymethyltransferase. GCV, glycine cleavage system. MetF, 5,10-methylenetetrahydrofolate reductase