title: Molecular cloning and characterization of Stevia rebaudiana UDP-glucosyltransferase.
abstract: We report here the cloning and characterization of a UDP-glucose flavonoid glucosyltransferase (srUFGT) in Stevia rebaudiana. The isolated cDNA was 1419 bp in length encoding 473 deduced amino acids with a predicted molecular mass of 53.2 kDa. The products of in vitro translation from an expression vector had anthocyanidins and steviol glucosyltransferase activity. Comparison of the activity of the recombinant UDP-glucosyltransferase toward a range of acceptor substrates suggests that it may participate in the synthesis of steviol glycosides. The results support the hypothesis that the flavonoid glucosyltransferases, which have a broad substrate specificity, may be not only involved in flavonoid glucosylation but also play a role in producing the water-soluble steviol-glycosides in S. rebaudiana.
authors.affiliation: College of Life Science, Xiamen University, Xiamen 361005.
authors.forename: Ling Bo
authors.initials: LB
authors.lastname: Ma
authors.forename: Da Bing
authors.initials: DB
authors.lastname: Zhang
authors.forename: Liang
authors.initials: L
authors.lastname: Chen
authors.forename: Mu Chuan
authors.initials: MC
authors.lastname: Chen
mesh_terms: D000595:Amino Acid Sequence; D000872:Anthocyanins / Q000378:metabolism; D003001:Cloning, Molecular; D004224:Diterpenes / Q000378:metabolism; D045786:Diterpenes, Kaurane; D017343:Genes, Plant; D005964:Glucosyltransferases / Q000737:chemistry / Q000235:genetics* / Q000502:physiology*; D008969:Molecular Sequence Data; D036625:Stevia / Q000201:enzymology* / Q000235:genetics; D013379:Substrate Specificity
chemical_list: D000872:Anthocyanins; D004224:Diterpenes; D045786:Diterpenes, Kaurane; C012042:steviol; D005964:Glucosyltransferases; C492332:UDP-glucose flavonoid glucosyltransferase, Stevia rebaudiana