Biology:3-methylquercetin 7-O-methyltransferase

From HandWiki
Short description: Class of enzymes
3-methylquercitin 7-O-methyltransferase
Identifiers
EC number2.1.1.82
CAS number96477-62-2
Databases
IntEnzIntEnz view
BRENDABRENDA entry
ExPASyNiceZyme view
KEGGKEGG entry
MetaCycmetabolic pathway
PRIAMprofile
PDB structuresRCSB PDB PDBe PDBsum
Gene OntologyAmiGO / QuickGO

In enzymology, a 3-methylquercetin 7-O-methyltransferase (EC 2.1.1.82) is an enzyme that catalyzes the chemical reaction

S-adenosyl-L-methionine + 5,7,3',4'-tetrahydroxy-3-methoxyflavone [math]\displaystyle{ \rightleftharpoons }[/math] S-adenosyl-L-homocysteine + 5,3',4'-trihydroxy-3,7-dimethoxyflavone

Thus, the two substrates of this enzyme are S-adenosyl methionine and 5,7,3',4'-tetrahydroxy-3-methoxyflavone (isorhamnetin), whereas its two products are S-adenosylhomocysteine and 5,3',4'-trihydroxy-3,7-dimethoxyflavone (rhamnazin).

This enzyme belongs to the family of transferases, specifically those transferring one-carbon group methyltransferases. The systematic name of this enzyme class is S-adenosyl-L-methionine:5,7,3',4'-tetrahydroxy-3-methoxyflavone 7-O-methyltransferase. Other names in common use include flavonol 7-O-methyltransferase, flavonol 7-methyltransferase, 7-OMT, S-adenosyl-L-methionine:3',4',5,7-tetrahydroxy-3-methoxyflavone, 7-O-methyltransferase, and 3-methylquercitin 7-O-methyltransferase [mis-spelt].

The enzyme can be found in Chrysosplenium americanum (American Golden Saxifrage).

References

  • "Enzymatic synthesis of polymethylated flavonols in Chrysosplenium americanum. I. Partial purification and some properties of S-adenosyl-L-methionine:flavonol 3-, 6-, 7-, and 4'-O-methyltransferases". Arch. Biochem. Biophys. 238 (2): 596–605. 1985. doi:10.1016/0003-9861(85)90205-X. PMID 3994393.