5,10-Methenyltetrahydrofolate (5,10-CH=THF) is a form of

tetrahydrofolate Tetrahydrofolic acid (THFA), or tetrahydrofolate, is a folic acid derivative. Metabolism Human synthesis Tetrahydrofolic acid is produced from dihydrofolic acid by dihydrofolate reductase. This reaction is inhibited by methotrexate. It is co ...

that is an intermediate in

metabolism Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cell ...

. 5,10-CH=THF is a

coenzyme A cofactor is a non-protein chemical compound or metallic ion that is required for an enzyme's role as a catalyst (a catalyst is a substance that increases the rate of a chemical reaction). Cofactors can be considered "helper molecules" that ass ...

that accepts and donates methenyl (CH=) groups. It is produced from

5,10-methylenetetrahydrofolate 5,10-Methylenetetrahydrofolate (N5,N10-Methylenetetrahydrofolate; 5,10-CH2-THF) is cofactor in several biochemical reactions. It exists in nature as the diastereoisomer R5,10-methylene-THF. As an intermediate in one-carbon metabolism, 5,10-CH2- ...

by either a NAD+ dependent methylenetetrahydrofolate dehydrogenase, or a NADP+ dependent dehydrogenase. It can also be produced as an intermediate in

histidine Histidine (symbol His or H) is an essential amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated –NH3+ form under biological conditions), a carboxylic acid group (which is in the de ...

catabolism, by

formiminotransferase cyclodeaminase Formimidoyltransferase cyclodeaminase or formiminotransferase cyclodeaminase (symbol FTCD in humans) is an enzyme that catalyzes the conversion of formiminoglutamate and tetrahydrofolate into formiminotetrahydrofolate and glutamate. Role in pa ...

, from 5-formiminotetrahydrofolate. 5,10-CH=THF is a substrate for

methenyltetrahydrofolate cyclohydrolase In enzymology, a methenyltetrahydrofolate cyclohydrolase () is an enzyme that catalyzes the chemical reaction :5,10-methenyltetrahydrofolate + H2O \rightleftharpoons 10-formyltetrahydrofolate Thus, the two substrates of this enzyme are 5,10-met ...

, which converts it into 10-formyltetrahydrofolate.

Interactive pathway map

References

{{DEFAULTSORT:Methenyltetrahydrofolate, 5,10- Folates Coenzymes