title: Biosynthesis of natural and novel C-glycosylflavones utilising recombinant Oryza sativa C-glycosyltransferase (OsCGT) and Desmodium incanum root proteins.
abstract: The rice C-glycosyltransferase (OsCGT) is one of only a small number of characterised plant C-glycosyltransferases (CGT) known. The enzyme C-glucosylates a 2-hydroxyflavanone substrate with UDP-glucose as the sugar donor to produce C-glucosyl-2-hydroxyflavanones. We tested substrate specificity of the enzyme, using synthetic 2-hydroxyflavanones, and showed it has the potential to generate known natural CGFs that have been isolated from rice and also other plants. In addition, we synthesised novel, unnatural 2-hydroxyflavanone substrates to test the B-ring chemical space of substrate accepted by the OsCGT and demonstrated the OsCGT capacity as a synthetic reagent to generate significant quantities of known and novel CGFs. Many B-ring analogues are tolerated within a confined steric limit. Finally the OsCGT was used to generate novel mono-C-glucosyl-2-hydroxyflavanones as putative biosynthetic intermediates to examine the potential of Desmodium incanum biosynthetic CGTs to produce novel di-C-glycosylflavones, compounds implicated in the allelopathic biological activity of Desmodium against parasitic weeds from the Striga genus.
authors.affiliation: College of Science, Northwest A&F University, Yangling, Shaanxi 712100, China; Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK. Electronic address: bing.hao@hotmail.com.
authors.forename: B
authors.initials: B
authors.lastname: Hao
authors.affiliation: Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK. Electronic address: john.caulfield@rothamsted.ac.uk.
authors.forename: J C
authors.initials: JC
authors.lastname: Caulfield
authors.affiliation: Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK. Electronic address: mary.hamilton@rothamsted.ac.uk.
authors.forename: M L
authors.initials: ML
authors.lastname: Hamilton
authors.affiliation: Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK. Electronic address: john.pickett@rothamsted.ac.uk.
authors.forename: J A
authors.initials: JA
authors.lastname: Pickett
authors.affiliation: International Centre of Insect Physiology and Ecology, P.O. Box 30772, Nairobi, Kenya. Electronic address: cmidega@icipe.org.
authors.forename: C A O
authors.initials: CA
authors.lastname: Midega
authors.affiliation: International Centre of Insect Physiology and Ecology, P.O. Box 30772, Nairobi, Kenya. Electronic address: zkhan@icipe.org.
authors.forename: Z R
authors.initials: ZR
authors.lastname: Khan
authors.affiliation: College of Science, Northwest A&F University, Yangling, Shaanxi 712100, China. Electronic address: wangjunru@nwsuaf.edu.cn.
authors.forename: J
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK. Electronic address: tony.hooper@rothamsted.ac.uk.
authors.forename: A M
authors.initials: AM
authors.lastname: Hooper
mesh_terms: D047309:Flavones / Q000737:chemistry / Q000378:metabolism*; D006027:Glycosides / Q000737:chemistry / Q000378:metabolism*; D016695:Glycosyltransferases / Q000378:metabolism*; D015394:Molecular Structure; D012275:Oryza / Q000737:chemistry / Q000201:enzymology / Q000235:genetics; D018517:Plant Roots / Q000378:metabolism*
chemical_list: D047309:Flavones; D006027:Glycosides; D016695:Glycosyltransferases
keywords: 2-Hydroxyflavanone; Biotechnological synthesis; C-Glucosylflavone; C-Glycosyltransferase; Chemical space; Di-C-glycosylflavone; Oryza sativa; OsCGT; Poaceae; Substrate specificity