These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Functional Characterization of a New Tea (Camellia sinensis) Flavonoid Glycosyltransferase.
    Author: Zhao X, Wang P, Li M, Wang Y, Jiang X, Cui L, Qian Y, Zhuang J, Gao L, Xia T.
    Journal: J Agric Food Chem; 2017 Mar 15; 65(10):2074-2083. PubMed ID: 28220704.
    Abstract:
    Tea (Camellia sinensis) is an important commercial crop, in which the high content of flavonoids provides health benefits. A flavonoid glycosyltransferase (CsUGT73A20), belonging to cluster IIIa, was isolated from tea plant. The recombinant CsUGT73A20 in Escherichia coli exhibited a broad substrate tolerance toward multiple flavonoids. Among them, kaempferol was the optimal substrate compared to quercetin, myricetin, naringenin, apigenin, and kaempferide. However, no product was detected when UDP-galactose was used as the sugar donor. The reaction assay indicated that rCsUGT73A20 performed multisite glycosidation toward flavonol compounds, mainly forming 3-O-glucoside and 7-O-glucoside in vitro. The biochemical characterization analysis of CsUGT73A20 showed more K7G product accumulated at pH 8.0, but K3G was the main product at pH 9.0. Kinetic analysis demonstrated that high pH repressed the glycosylation reaction at the 7-OH site in vitro. Besides, the content of five flavonol-glucosides was increased in CsUGT73A20-overexpressing tobaccos (Nicotiana tabacum).
    [Abstract] [Full Text] [Related] [New Search]