Reaction participants Show >> << Hide
- Name help_outline a 7-O-hydroxy-flavonol Identifier CHEBI:52267 Charge 0 Formula C15H3O4R7 SMILEShelp_outline C1(=C(C(=C(C2=C1OC(=C(C2=O)O)C3=CC(=C(C(=C3*)*)*)*)*)*)O)* 2D coordinates Mol file for the small molecule Search links Involved in 1 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline UDP-α-D-glucose Identifier CHEBI:58885 (Beilstein: 3827329) help_outline Charge -2 Formula C15H22N2O17P2 InChIKeyhelp_outline HSCJRCZFDFQWRP-JZMIEXBBSA-L SMILEShelp_outline OC[C@H]1O[C@H](OP([O-])(=O)OP([O-])(=O)OC[C@H]2O[C@H]([C@H](O)[C@@H]2O)n2ccc(=O)[nH]c2=O)[C@H](O)[C@@H](O)[C@@H]1O 2D coordinates Mol file for the small molecule Search links Involved in 231 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline a flavonol 7-O-β-D-glucoside Identifier CHEBI:52144 Charge 0 Formula C21H13O9R7 SMILEShelp_outline C12=C(C(=C(C(=C2C(C(=C(O1)C3=CC(=C(C(=C3*)*)*)*)O)=O)*)*)O[C@H]4[C@@H]([C@H]([C@@H]([C@H](O4)CO)O)O)O)* 2D coordinates Mol file for the small molecule Search links Involved in 3 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline H+ Identifier CHEBI:15378 Charge 1 Formula H InChIKeyhelp_outline GPRLSGONYQIRFK-UHFFFAOYSA-N SMILEShelp_outline [H+] 2D coordinates Mol file for the small molecule Search links Involved in 9,431 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline UDP Identifier CHEBI:58223 Charge -3 Formula C9H11N2O12P2 InChIKeyhelp_outline XCCTYIAWTASOJW-XVFCMESISA-K SMILEShelp_outline O[C@@H]1[C@@H](COP([O-])(=O)OP([O-])([O-])=O)O[C@H]([C@@H]1O)n1ccc(=O)[nH]c1=O 2D coordinates Mol file for the small molecule Search links Involved in 576 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
Cross-references
| RHEA:23164 | RHEA:23165 | RHEA:23166 | RHEA:23167 | |
|---|---|---|---|---|
| Reaction direction help_outline | undefined | left-to-right | right-to-left | bidirectional |
| UniProtKB help_outline |
|
|||
| EC numbers help_outline | ||||
| Gene Ontology help_outline | ||||
| KEGG help_outline | ||||
| MetaCyc help_outline |
Publications
-
UDP-glucose: flavonol 7-O-glucosyltransferase activity in flower extracts of Chrysanthemum segetum.
Stich K., Halbwirth H., Wurst F., Forkmann G.
The yellow colour of Chrysanthemum segetum petals is due to the presence of the 7-O-glucosides of quercetin and particularly gossypetin (8-hydroxyquercetin). In petal extracts of C. segetum an enzyme was demonstrated which catalyzes the transfer of the glucosyl moiety of uridine 5'-diphosphoglucos ... >> More
The yellow colour of Chrysanthemum segetum petals is due to the presence of the 7-O-glucosides of quercetin and particularly gossypetin (8-hydroxyquercetin). In petal extracts of C. segetum an enzyme was demonstrated which catalyzes the transfer of the glucosyl moiety of uridine 5'-diphosphoglucose (UDPG) to the 7-hydroxyl group of flavonols with gossypetin and quercetin as the best substrates. Besides flavonols flavanones and flavones were found to be glucosylated in the 7-position. The pH-optimum of the reaction highly depended on the substrate used. With quercetin as substrate, maximal enzyme activity occurred at a pH of 8.25 and a temperature of 25 degrees C, but 7-O-glucosylation also proceeded at low temperatures. Studies on temperature stability revealed, that there was no influence on the glucosylation reaction up to 40 degrees C. Higher temperatures led to a loss of enzyme activity. Using gossypetin as a substrate a similar course of temperature stability was observed. Addition of Mg2+, Ca2+ and KCN slightly stimulated 7-O-glucosylation, whereas Co2+, Cu2+, Fe2+, Hg2+, p-hydroxymercuribenzoate and N-ethylmaleimide showed a strong inhibitory effect. Additional enzymatic studies were performed with the commercial strain "Stern des Orients" where gossypetin 7-O-glucoside is restricted to the inner parts of the petals. For enzyme extracts from both parts of the petals gossypetin was found to be the most attractive substrate. In comparison to quercetin (133.4 mu kat/kg protein) an about three times higher specific activity of the 7-O-glucosyltransferase(s) was determined with gossypetin (382.1 mu kat/kg protein) as substrate, indicating that hydroxylation of quercetin in 8-position to gossypetin precedes 7-O-glucosylation. << Less
Z Naturforsch C J Biosci 52:153-158(1997) [PubMed] [EuropePMC]
-
Bio-fermentation of modified flavonoids: an example of in vivo diversification of secondary metabolites.
Willits M.G., Giovanni M., Prata R.T.N., Kramer C.M., De Luca V., Steffens J.C., Graser G.
A bio-fermentation technique was used for the in vivo diversification of flavonoid structures based on expression in Escherichia coli of six O-methyltransferases (OMTs) from Mentha x piperita and one O-glucosyltransferase (GT) each from Arabidopsis thaliana and Allium cepa. Enzymes were shown to b ... >> More
A bio-fermentation technique was used for the in vivo diversification of flavonoid structures based on expression in Escherichia coli of six O-methyltransferases (OMTs) from Mentha x piperita and one O-glucosyltransferase (GT) each from Arabidopsis thaliana and Allium cepa. Enzymes were shown to be regio-specific in in vitro experiments and modified a broad range of flavonoid substrates at various positions. Using the flavonol quercetin as a model substrate, we show that the product spectrum produced with the in vivo approach is identical to that found in vitro. Additionally, using mixed cultures of E. coli expressing different classes of modifying genes (OMTs and GTs), the production of polymethylated flavonoid glucosides was observed. This report demonstrates the potential to increase the structural diversity of plant secondary metabolites using a multi-enzyme, bio-fermentation approach. << Less
Phytochemistry 65:31-41(2004) [PubMed] [EuropePMC]
This publication is cited by 23 other entries.