Ep7GT, a glycosyltransferase with sugar donor flexibility from Epimedium pseudowushanense, catalyzes the 7-O-glycosylation of baohuoside

Abstract

A novel glycosyltransferase from Epimedium pseudowushanense, Ep7GT, regiospecifically catalyzes the 7-O-glucosylation of baohuoside to form icariin and shows sugar donor/acceptor promiscuity to yield different flavonoid glycosides.

Exploring the Catalytic Flexibility and Reversibility of Plant Glycosyltransferase HtUGT72AS1 for Glycodiversification of Phenolic Compounds

“…Thus, HtUGT72AS1 appears to be naturally selective for the structure of flavonols. High conversions (>80%) were also observed when genistein (10), phloretin (12), and xanthone (14) were used as substrates. In addition to flavonoids, HtUGT72AS1 was capable of glucosylating other types of natural and unnatural compounds to generating O-, N-, and Sglycosides, including xanthene (15), benzophenone (16), anthraquinones (17)(18)(19), lignans (20,21), coumarin (22), curcumin (23), stilbene (24), alkaloids (25−27), naphthalene (28), simple aromatics (29−39), and benzofurazan (40).…”

A Novel 3-O-rhamnoside: 2″-O-xylosyltransferase Responsible for Terminal Modification of Prenylflavonol Glycosides in Epimedium pubescens Maxim.

“…The most abundant compounds are icariin, epimedin A, epimedin B, and epimedin C. In particular, they all have a different disaccharide O-linked at 3-OH and a glucose moiety at 7-OH (Figure 1b). The rhamnosyltransferase and glucosyltransferase genes responsible for the 3-O-rhamnosylation and 7-O-glucosylation of prenylflavonols have been identified in the genus Epimedium [6][7][8][9], but the glycosyltransferases remain unknown for the synthesis of disaccharides at 3-OH.…”

“…The new approaches of synthetic biology may provide an alternative way to produce prenylated flavonol glycosides for medicinal use, which is largely dependent on the elucidation of the biosynthetic pathway of these compounds. To date, a few glycosyltransferase genes have been identified and cloned from the genus Epimedium and were proven to only transfer a sugar moiety to either the 3-OH or 7-OH position of prenylated flavonols to form prenylated flavonol glycosides [6][7][8][9][10][11]. Based on the previous studies in the genus Epimedium [6][7][8][9], we assumed the detailed scheme of prenylflavonoid glycoside biosynthesis (Figure 1b).…”

“…To date, a few glycosyltransferase genes have been identified and cloned from the genus Epimedium and were proven to only transfer a sugar moiety to either the 3-OH or 7-OH position of prenylated flavonols to form prenylated flavonol glycosides [6][7][8][9][10][11]. Based on the previous studies in the genus Epimedium [6][7][8][9], we assumed the detailed scheme of prenylflavonoid glycoside biosynthesis (Figure 1b). Although a few glycosyltransferase (GT) genes were reported in different species of the Epimedium genus, the critical GT genes that are responsible for transferring an additional sugar moiety to the rhamnose moiety at 3-OH of icariin to form epimedin A, epimedin B, or epimedin C remain to be determined [7,8].…”

Genome-wide analysis of UGT gene family identified key gene for the biosynthesis of bioactive flavonol glycosides in Epimedium pubescens Maxim.

“…Glycosylation directly or indirectly affects the medicinal activity by optimizing the properties of pharmaceutical compounds [ 5 ]. To date, a few UGTs have been proven to be involved in the biosynthesis of icariin, one of the most important active ingredients of flavonol glycosides in Epimedium [ [16] , [17] , [18] , [19] ]. However, the function of hundreds of UGT gene members remains unclear.…”