Isoflavone 7-O-methyltransferase
| Isoflavone 7-O-methyltransferase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC no. | 2.1.1.150 | ||||||||
| CAS no. | 136111-54-1 | ||||||||
| Databases | |||||||||
| BRENDA | enzyme data | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | enzyme entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| Rhea | reactions | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| |||||||||
Isoflavone 7-O-methyltransferase (EC 2.1.1.150) is an enzyme that catalyzes a general chemical reaction which converts 7-hydroxyisoflavones to their 7-methoxy derivatives.[1][2]
For example, genistein is converted to prunetin:
The methylation reaction requires the cofactor, S-adenosyl methionine (SAM), to provide the methyl group, leaving the byproduct S-adenosyl-L-homocysteine (SAH). The enzyme was characterised from alfalfa.[3][4] It is also capable of methylating daidzein and these reactions are often induced by attack by a pathogen, with the plant responding to an elicitor by biosynthesis of a phytoalexin.[5][6][7]
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.[8]
References
- ↑ Edwards R, Dixon RA (1991). "Isoflavone O-methyltransferase activities in elicitor-treated cell suspension cultures of Medicago sativa". Phytochemistry. 30 (8): 2597–2606. Bibcode:1991PChem..30.2597E. doi:10.1016/0031-9422(91)85107-B.
- ↑ 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 (1): 121–9. doi:10.1006/abbi.1996.0539. PMID 8951042.
- ↑ 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 (9): 1689–702. doi:10.1105/tpc.12.9.1689. PMC 149079. PMID 11006341.
- ↑ 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 (1): 43–54. doi:10.1023/A:1005938121453. PMID 9484461. S2CID 22861966.
- ↑ 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 (12): 2643–58. Bibcode:2001PlanC..13.2643L. doi:10.1105/tpc.010382. PMC 139479. 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 (3): 271–9. doi:10.1038/85029. PMID 11224575. S2CID 36170487.
- ↑ 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 (2): 219–27. doi:10.1023/A:1005985609313. PMID 9484434. S2CID 23711170.
- ↑ Enzyme 2.1.1.150 at KEGG Pathway Database.