|Superclasses:||Reactions Classified By Conversion Type → Simple Reactions → Chemical Reactions|
|Reactions Classified By Substrate → Small-Molecule Reactions|
EC Number: 188.8.131.52
Enzymes and Genes:
|Glycyrrhiza echinata:||2,7,4'-trihydroxyisoflavanone-4'-O-methyltransferase: HI4'OMT|
|Lotus japonicus:||2,7,4'-trihydroxyisoflavanone-4'-O-methyltransferase: HI4'OMT|
In Pathway: formononetin biosynthesis
The direction shown, i.e. which substrates are on the left and right sides, is in accordance with the direction in which it was curated.
Most BioCyc compounds have been protonated to a reference pH value of 7.3. Please see the PGDB Concepts Guide for more information.
Mass balance status: Balanced.
Enzyme Commission Primary Name: 2,7,4′-trihydroxyisoflavanone 4′-O-methyltransferase
Enzyme Commission Synonyms: SAM:2,7,4'-trihydroxyisoflavanone 4'-O-methyltransferase, HI4'OMT, HMM1, MtIOMT5, S-adenosyl-L-methionine:2,7,4'-trihydroxyisoflavanone 4'-O-methyltransferase
Standard Gibbs Free Energy (ΔrG'° in kcal/mol): -4.360016 [Latendresse13]
Enzyme Commission Summary:
Specifically methylates 2,4',7-trihydroxyisoflavanone on the 4'-position. No activity with isoflavones [Deavours06]. The enzyme is involved in formononetin biosynthesis in legumes [Akashi03]. The protein from pea ( Pisum sativum) also methylates (+)-6a-hydroxymaackiain at the 3-position (cf. EC 184.108.40.2060, (+)-6a-hydroxymaackiain 3-O-methyltransferase) [Akashi06].
Akashi03: Akashi T, Sawada Y, Shimada N, Sakurai N, Aoki T, Ayabe S (2003). "cDNA cloning and biochemical characterization of S-adenosyl-L-methionine: 2,7,4'-trihydroxyisoflavanone 4'-O-methyltransferase, a critical enzyme of the legume isoflavonoid phytoalexin pathway." Plant Cell Physiol 44(2);103-12. PMID: 12610212
Akashi06: Akashi T, VanEtten HD, Sawada Y, Wasmann CC, Uchiyama H, Ayabe S (2006). "Catalytic specificity of pea O-methyltransferases suggests gene duplication for (+)-pisatin biosynthesis." Phytochemistry 67(23);2525-30. PMID: 17067644
Deavours06: Deavours BE, Liu CJ, Naoumkina MA, Tang Y, Farag MA, Sumner LW, Noel JP, Dixon RA (2006). "Functional analysis of members of the isoflavone and isoflavanone O-methyltransferase enzyme families from the model legume Medicago truncatula." Plant Mol Biol 62(4-5);715-33. PMID: 17001495
Liu06a: Liu CJ, Deavours BE, Richard SB, Ferrer JL, Blount JW, Huhman D, Dixon RA, Noel JP (2006). "Structural basis for dual functionality of isoflavonoid O-methyltransferases in the evolution of plant defense responses." Plant Cell 18(12);3656-69. PMID: 17172354
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