Functional Characterization of a New Tea (Camellia sinensis) Flavonoid Glycosyltransferase

被引：51

作者：

Zhao, Xianqian ^{[1
,2
]}

Wang, Peiqiang ^{[1
]}

Li, Mingzhuo ^{[1
]}

Wang, Yeru ^{[2
]}

Jiang, Xiaolan ^{[1
]}

Cui, Lilan ^{[1
]}

Qian, Yumei ^{[1
]}

Zhuang, Juhua ^{[1
]}

Gao, Liping ^{[2
]}

Xia, Tao ^{[1
]}

机构：

[1] Anhui Agr Univ, State Key Lab Tea Plant Biol & Utilizat, Hefei 230036, Anhui, Peoples R China

[2] Anhui Agr Univ, Sch Life Sci, 130 West Changjiang Rd, Hefei 230036, Anhui, Peoples R China

来源：

JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY | 2017年 / 65卷 / 10期

关键词：

flavonoids glycosyltransferase; multisite glycosidation; Camellia sinensis; GREEN TEA; BIOCHEMICAL-CHARACTERIZATION; PLANT GLYCOSYLTRANSFERASES; REGIOSELECTIVE SYNTHESIS; RECOMBINANT EXPRESSION; ARABIDOPSIS-THALIANA; ESCHERICHIA-COLI; GLUCOSYLTRANSFERASES; CLONING; IDENTIFICATION;

D O I：

10.1021/acs.jafc.6b05619

中图分类号：

S [农业科学];

学科分类号：

09 ;

摘要：

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 ilia, 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).

引用

页码：2074 / 2083

页数：10