Isoflavone 7-O-methyltransferase

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In enzymology, an isoflavone 7-O-methyltransferase (EC 2.1.1.150) is an enzyme that catalyzes the chemical reaction

S-adenosyl-L-methionine + a 7-hydroxyisoflavone $\rightleftharpoons$ S-adenosyl-L-homocysteine + a 7-methoxyisoflavone

Thus, the two substrates of this enzyme are S-adenosyl methionine and 7-hydroxyisoflavone, whereas its two products are S-adenosylhomocysteine and 7-methoxyisoflavone.

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:hydroxyisoflavone 7-O-methyltransferase. This enzyme participates in isoflavonoid biosynthesis.

[edit] References

IUBMB entry for 2.1.1.150
BRENDA references for 2.1.1.150 (Recommended.)
PubMed references for 2.1.1.150
PubMed Central references for 2.1.1.150
Google Scholar references for 2.1.1.150
Edwards R and Dixon RA (1991). "Isoflavone O-methyltransferase activities in elicitor-treated cell suspension cultures of Medicago sativa". Phytochemistry 30: 2597–2606. doi:10.1016/0031-9422(91)85107-B.
He XZ, Dixon RA (2000). "Genetic manipulation of isoflavone 7-O-methyltransferase enhances biosynthesis of 4'-O-methylated isoflavonoid phytoalexins and disease resistance in alfalfa". Plant. Cell. 12: 1689–702. doi:10.1105/tpc.12.9.1689. PMID 11006341.
He XZ, Dixon RA (1996). "Affinity chromatography, substrate/product specificity, and amino acid sequence analysis of an isoflavone O-methyltransferase from alfalfa (Medicago sativa L.)". Arch. Biochem. Biophys. 336: 121–9. doi:10.1006/abbi.1996.0539. PMID 8951042.
He XZ, Reddy JT, Dixon RA (1998). "Stress responses in alfalfa (Medicago sativa L). XXII. cDNA cloning and characterization of an elicitor-inducible isoflavone 7-O-methyltransferase". Plant. Mol. Biol. 36: 43–54. doi:10.1023/A:1005938121453. PMID 9484461.
Liu CJ, Dixon RA (2001). "Elicitor-induced association of isoflavone O-methyltransferase with endomembranes prevents the formation and 7-O-methylation of daidzein during isoflavonoid phytoalexin biosynthesis". Plant. Cell. 13: 2643–58. doi:10.1105/tpc.13.12.2643. PMID 11752378.
Zubieta C, He XZ, Dixon RA, Noel JP (2001). "Structures of two natural product methyltransferases reveal the basis for substrate specificity in plant O-methyltransferases". Nat. Struct. Biol. 8: 271–9. doi:10.1038/85029. PMID 11224575.
Christensen AB, Gregersen PL, Olsen CE, Collinge DB (1998). "A flavonoid 7-O-methyltransferase is expressed in barley leaves in response to pathogen attack". Plant. Mol. Biol. 36: 219–27. doi:10.1023/A:1005985609313. PMID 9484434.