Compounds > 2-7-4--trihydroxyisoflavanone

2-7-4--trihydroxyisoflavanone and daidzein

2-7-4--trihydroxyisoflavanone has been researched along with daidzein* in 2 studies

Other Studies

2 other study(ies) available for 2-7-4--trihydroxyisoflavanone and daidzein

Article	Year
Elicitor-induced association of isoflavone O-methyltransferase with endomembranes prevents the formation and 7-O-methylation of daidzein during isoflavonoid phytoalexin biosynthesis. The Plant cell, 2001, Volume: 13, Issue:12 The bioactive isoflavonoids of the Leguminosae often are methylated on the 4'-position of their B-rings. Paradoxically, reverse genetic evidence implicates alfalfa isoflavone O-methyltransferase (IOMT) in the biosynthesis of 4'-O-methylated isoflavonoids such as the phytoalexin medicarpin in vivo, whereas biochemical studies indicate that IOMT has strict specificity for methylation of the A-ring 7-hydroxyl of daidzein, the presumed substrate for O-methylation, in vitro. Radiolabeling and isotope dilution studies now confirm that daidzein is not an intermediate in isoflavonoid phytoalexin biosynthesis in alfalfa. Furthermore, protein gel blot analysis and confocal microscopy of a transiently expressed IOMT-green fluorescent protein fusion in alfalfa leaves show that the operationally soluble IOMT localizes to endomembranes after elicitation of the isoflavonoid pathway. We propose that IOMT colocalizes with the endoplasmic reticulum-associated isoflavone synthase cytochrome P450 to ensure rapid B-ring methylation of the unstable 2,4',7-trihydroxyisoflavanone product of isoflavone synthase, thereby preventing its dehydration to daidzein and subsequent A-ring methylation by free IOMT. In this way, metabolic channeling at the entry point into isoflavonoid phytoalexin biosynthesis protects an unstable intermediate from an unproductive metabolic conversion. Topics: Benzopyrans; Cells, Cultured; Endoplasmic Reticulum; Flavanones; Flavonoids; Ion Channels; Isoflavones; Isotope Labeling; Medicago sativa; Methylation; Methyltransferases; Microsomes; Oxygenases; Phytoalexins; Plant Extracts; Plant Leaves; Plants, Genetically Modified; Pterocarpans; Sesquiterpenes; Terpenes	2001
New scheme of the biosynthesis of formononetin involving 2,7,4'-trihydroxyisoflavanone but not daidzein as the methyl acceptor. Bioscience, biotechnology, and biochemistry, 2000, Volume: 64, Issue:10 Glycyrrhiza echinata cell-free extract produced isoformononetin by the 7-O-transmethylation of daidzein from S-adenosyl-L-methionine (SAM). When the yeast microsome expressing 2-hydroxyisoflavanone synthase was mixed with the cell-free extract and incubated with liquiritigenin and SAM, formononetin emerged. Furthermore, the cell-free extract yielded formononetin on incubation with 2,7,4'-trihydroxyisoflavanone and SAM. We propose a novel pathway of formononetin biosynthesis involving 2,7,4'-trihydroxyisoflavanone as the methyl acceptor. Topics: Cell-Free System; Chromatography, High Pressure Liquid; Isoflavones	2000

Article

Year

Elicitor-induced association of isoflavone O-methyltransferase with endomembranes prevents the formation and 7-O-methylation of daidzein during isoflavonoid phytoalexin biosynthesis.

The Plant cell, 2001, Volume: 13, Issue:12

The bioactive isoflavonoids of the Leguminosae often are methylated on the 4'-position of their B-rings. Paradoxically, reverse genetic evidence implicates alfalfa isoflavone O-methyltransferase (IOMT) in the biosynthesis of 4'-O-methylated isoflavonoids such as the phytoalexin medicarpin in vivo, whereas biochemical studies indicate that IOMT has strict specificity for methylation of the A-ring 7-hydroxyl of daidzein, the presumed substrate for O-methylation, in vitro. Radiolabeling and isotope dilution studies now confirm that daidzein is not an intermediate in isoflavonoid phytoalexin biosynthesis in alfalfa. Furthermore, protein gel blot analysis and confocal microscopy of a transiently expressed IOMT-green fluorescent protein fusion in alfalfa leaves show that the operationally soluble IOMT localizes to endomembranes after elicitation of the isoflavonoid pathway. We propose that IOMT colocalizes with the endoplasmic reticulum-associated isoflavone synthase cytochrome P450 to ensure rapid B-ring methylation of the unstable 2,4',7-trihydroxyisoflavanone product of isoflavone synthase, thereby preventing its dehydration to daidzein and subsequent A-ring methylation by free IOMT. In this way, metabolic channeling at the entry point into isoflavonoid phytoalexin biosynthesis protects an unstable intermediate from an unproductive metabolic conversion.

Topics: Benzopyrans; Cells, Cultured; Endoplasmic Reticulum; Flavanones; Flavonoids; Ion Channels; Isoflavones; Isotope Labeling; Medicago sativa; Methylation; Methyltransferases; Microsomes; Oxygenases; Phytoalexins; Plant Extracts; Plant Leaves; Plants, Genetically Modified; Pterocarpans; Sesquiterpenes; Terpenes

2001

New scheme of the biosynthesis of formononetin involving 2,7,4'-trihydroxyisoflavanone but not daidzein as the methyl acceptor.

Bioscience, biotechnology, and biochemistry, 2000, Volume: 64, Issue:10

Glycyrrhiza echinata cell-free extract produced isoformononetin by the 7-O-transmethylation of daidzein from S-adenosyl-L-methionine (SAM). When the yeast microsome expressing 2-hydroxyisoflavanone synthase was mixed with the cell-free extract and incubated with liquiritigenin and SAM, formononetin emerged. Furthermore, the cell-free extract yielded formononetin on incubation with 2,7,4'-trihydroxyisoflavanone and SAM. We propose a novel pathway of formononetin biosynthesis involving 2,7,4'-trihydroxyisoflavanone as the methyl acceptor.

Topics: Cell-Free System; Chromatography, High Pressure Liquid; Isoflavones

2000