| Type: | Family | Name: | Thymidylate synthase |
| Description: | Thymidylate synthase () [, ] catalyzes the reductive methylationof dUMP to dTMP with concomitant conversion of 5,10-methylenetetrahydrofolate to dihydrofolate:5,10-methylenetetrahydrofolate + dUMP = dihydrofolate + dTMP This provides the sole de novopathway for production of dTMP and is the only enzyme in folate metabolism in which the5,10-methylenetetrahydrofolate is oxidised during one-carbon transfer [].The enzyme is essential for regulating the balanced supply of the 4 DNA precursors in normal DNA replication: defects in the enzyme activityaffecting the regulation process cause various biological and genetic abnormalities, such as thymineless death []. The enzyme is an important target for certain chemotherapeutic drugs. Thymidylate synthase is an enzyme of about 30 to 35 Kd in most species except in protozoan and plants where it exists as a bifunctional enzyme that includesa dihydrofolate reductase domain [].A cysteine residue is involved in the catalytic mechanism (it covalently binds the 5,6-dihydro-dUMP intermediate). The sequence around the active site ofthis enzyme is conserved from phages to vertebrates. | Short Name: | Thymidylate_synthase |
