02540nas a2200277   4500008004100000022001400041245011000055210006900165260007900234300001200313490000800325520151400333653001401847653001801861653002401879653002301903653005501926653002301981100001802004700002802022700002602050700002702076700000902103700002702112856012302139       2013                        eng d  a0273-228900aFunctional characterization of a flavonoid glycosyltransferase gene from withania somnifera (Ashwagandha)0 aFunctional characterization of a flavonoid glycosyltransferase g  a999 RIVERVIEW DRIVE SUITE 208, TOTOWA, NJ 07512 USAbHUMANA PRESS INCcJUN  a729-7410 v1703 a<p>Glycosylation of flavonoids is mediated by family 1 uridine diphosphate (UDP)-dependent glycosyltransferases (UGTs). Until date, there are few reports on functionally characterized flavonoid glycosyltransferases from Withania somnifera. In this study, we cloned the glycosyltransferase gene from W. somnifera (UGT73A16) showing 85-92 % homology with UGTs from other plants. UGT73A16 was expressed as a His(6)-tagged fusion protein in Escherichia coli. Several compounds, including flavonoids, were screened as potential substrates for UGT73A16. HPLC analysis and hypsochromic shift indicated that UGT73A16 transfers a glucose molecule to several different flavonoids. Based on kinetic parameters, UGT73A16 shows more catalytic efficiency towards naringenin. Here, we explored UGT73A16 of W. somnifera as whole cell catalyst in E. coli. We used flavonoids (genistein, apigenin, kaempferol, naringenin, biochanin A, and daidzein) as substrates for this study. More than 95 % of the glucoside products were released into the medium, facilitating their isolation. Glycosylation of substrates occurred on the 7- and 3-hydroxyl group of the aglycone. UGT73A16 also displayed regiospecific glucosyl transfer activity towards 3-hydroxy flavone compound, which is the backbone of all flavonols and also for a chemically synthesized compound, not found naturally. The present study generates essential knowledge and molecular as well as biochemical tools that allow the verification of UGT73A16 in glycosylation.</p>10aFlavonoid10aglycosylation10aGlycosyltransferase10aHypsochromic shift10aPlant secondary product glycosyltransferase (PSPG)10aWithania somnifera1 aSingh, Somesh1 aVishwakarma, Rishi., K.1 aKumar, R., J. Santosh1 aSonawane, Prashant, D.1 aRuby1 aKhan, Bashir, Mohammad  uhttps://library.ncl.res.in/content/functional-characterization-flavonoid-glycosyltransferase-gene-withania-somnifera-002294nas a2200253   4500008004100000022001400041245011800055210006900173260005700242300001400299490000700313520138200320653001301702653001501715653002401730653002301754100002601777700000901803700001801812700002701830700002401857700002701881856013201908       2013                        eng d  a0735-964000aFunctional characterization of a glucosyltransferase specific to flavonoid 7-O-glucosides from withania somnifera0 aFunctional characterization of a glucosyltransferase specific to  a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGERcOCT  a1100-11080 v313 a<p>Flavonoids are a large class of phenylpropanoid-derived secondary metabolites, which are usually glycosylated by UDP-glycosyltransferases with one or more sugar groups. Here, we report the cloning and biochemical characterization of a flavonoid glycosyltransferase gene from Withania somnifera (WsGT), which is an important medicinal plant used in Ayurvedic formulations. Using PCR primers, designed for a highly conserved region of previously reported glycosyltransferases, we were able to isolate the corresponding fragment of the WsGT gene. Rapid amplification of cDNA ends (RACE) was then employed to isolate full-length cDNA, which had an open reading frame of 1,371 bp that encode for 456 amino acids. Phylogenetic analysis indicated that WsGT was similar to that of family 1 GT-B glycosyltransferase. Biochemical analysis revealed that WsGT interacts with UDP-glucose and was capable of regiospecifically glycosylating flavonoid-7-ols, such as apigenin, naringenin, luteolin, diadzein and genistein. Expression profiling studies showed that WsGT was highly expressed in young and mature leaves of W. somnifera. Furthermore, exposure to salicylic acid enhanced the expression of WsGT in the leaves and heat shock treatment resulted in decreased expression of WsGT after an initial increase. This may suggest the role of WsGT in response to abiotic/biotic stresses.</p>10aDiadzein10aFlavonoids10aGlycosyltransferase10aWithania somnifera1 aKumar, R., J. Santosh1 aRuby1 aSingh, Somesh1 aSonawane, Prashant, D.1 aVishwakarma, R., K.1 aKhan, Bashir, Mohammad  uhttps://library.ncl.res.in/content/functional-characterization-glucosyltransferase-specific-flavonoid-7-o-glucosides-withania-0