enzymology Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. A ...

, a methylenetetrahydromethanopterin dehydrogenase () is an

enzyme Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. A ...

that

catalyzes Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...

the

chemical reaction A chemical reaction is a process that leads to the IUPAC nomenclature for organic transformations, chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the pos ...

:5,10-methylenetetrahydromethanopterin + coenzyme F₄₂₀

\rightleftharpoons

5,10-methenyltetrahydromethanopterin + reduced coenzyme F₄₂₀ Thus, the two substrates of this enzyme are 5,10-methylenetetrahydromethanopterin and

coenzyme F420 Coenzyme F420 or 8-hydroxy-5-deazaflavin is a coenzyme (sometimes called a cofactor) involved in redox reactions in methanogens, in many Actinomycetota, and sporadically in other bacterial lineages. It is a flavin derivative. The coenzyme is a ...

, whereas its two products are 5,10-methenyltetrahydromethanopterin and reduced coenzyme F420. This enzyme belongs to the family of

oxidoreductase In biochemistry, an oxidoreductase is an enzyme that catalyzes the transfer of electrons from one molecule, the reductant, also called the electron donor, to another, the oxidant, also called the electron acceptor. This group of enzymes usually ut ...

s, specifically those acting on the CH-NH group of donors with other acceptors. The systematic name of this enzyme class is 5,10-methylenetetrahydromethanopterin:coenzyme-F420 oxidoreductase. Other names in common use include N5,N10-methylenetetrahydromethanopterin dehydrogenase, and 5,10-methylenetetrahydromethanopterin dehydrogenase. This enzyme participates in

folate biosynthesis Folate, also known as vitamin B9 and folacin, is one of the B vitamins. Manufactured folic acid, which is converted into folate by the body, is used as a dietary supplement and in food fortification as it is more stable during processing and ...

Structural studies

As of late 2007, 4 structures have been solved for this class of enzymes, with PDB accession codes , , , and .

References

* * EC 1.5.98 Enzymes of known structure {{1.5-enzyme-stub