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The dUTPase, known as dUTP diphophohydrolase, hydrolyzes the deoxyuridine triphosphate (dUTP) to deoxyuridine monophosphate (dUMP). The reaction is as follows:

$dUTP+H_{2}O\underset{dATPase}{→}dUMP+P{P}_i$

Thymidylate synthase is an enzyme that transfers a methyl group to the deoxyuridine monophosphate (dUMP), converting it into deoxythymidine monophosphate (dTMP). It involves the removal of methyl from $N^5,N^{10}-Methylenetetrahydrofolate$to produce dihydrofolate (DHF). The reaction is as follows:

$dUMP+N^5,N^{10}-Methylenetetrahydrofolate\underset{thymidylatesynthase}{→}dTMP+Dihydrofolate$

The dihydrofolatereductase catalyzes the formation of tetrahydrofolate (THF) from the dihydrofolate (DHF) by reducing NADPH +$H^{+}$ to$NAD{P}^{+}$ . The reaction is as follows:

$DHF+NADH+H^{+}\underset{Dihydrofolatereductase}{→}THF+NAD{P}^{+}$

The THF is converted to $N^5,N^{10}-Methylenetetrahydrofolate$by serine hydroxymethyl-transferase so that it can be used in dMP synthesis.