5-formyltetrahydrofolate cyclo-ligase

In enzymology, a 5-formyltetrahydrofolate cyclo-ligase (EC 6.3.3.2) is an enzyme that catalyzes the chemical reaction

ATP + 5-formyltetrahydrofolate (folinic acid) ${\displaystyle \rightleftharpoons }$ ADP + phosphate + 5,10-methenyltetrahydrofolate

Thus, the two substrates of this enzyme are ATP and 5-formyltetrahydrofolate, whereas its 3 products are ADP, phosphate, and 5,10-methenyltetrahydrofolate.

This enzyme belongs to the family of ligases, specifically the cyclo-ligases, which form carbon-nitrogen bonds. The systematic name of this enzyme class is 5-formyltetrahydrofolate cyclo-ligase (ADP-forming). Other names in common use include 5,10-methenyltetrahydrofolate synthetase (MTHFS), formyltetrahydrofolic cyclodehydrase, and 5-formyltetrahydrofolate cyclodehydrase. This enzyme participates in one carbon pool by folate.