80952-71-2Relevant articles and documents
Glycoside Hydrolase Family 39 β-Xylosidases Exhibit β-1,2-Xylosidase Activity for Transformation of Notoginsenosides: A New EC Subsubclass
Zhang, Rui,Li, Na,Xu, Shujing,Han, Xiaowei,Li, Chunyan,Wei, Xin,Liu, Yu,Tu, Tao,Tang, Xianghua,Zhou, Junpei,Huang, Zunxi
, (2019/03/26)
β-1,2-Xylosidase activity has not been recorded as an EC subsubclass. In this study, phylogenetic analysis and multiple sequence alignments revealed that characterized β-xylosidases of glycoside hydrolase family (GH) 39 were classified into the same subgroup with conserved amino acid residue positions participating in substrate recognition. Protein-ligand docking revealed that seven of these positions were probably essential to bind xylose-glucose, which is linked by a β-1,2-glycosidic bond. Amino acid residues in five of the seven positions are invariant, while those in two of the seven positions are variable with low frequency. Both the wild-type β-xylosidase rJB13GH39 and its mutants with mutation at the two positions exhibited β-1,2-xylosidase activity, as they hydrolyzed o-nitrophenyl-β-d-xylopyranoside and transformed notoginsenosides R1 and R2 to ginsenosides Rg1 and Rh1, respectively. The results suggest that all of these characterized GH 39 β-xylosidases probably show β-1,2-xylosidase activity, which should be assigned an EC number with these β-xylosidases as representatives.
Use of a Promiscuous Glycosyltransferase from Bacillus subtilis 168 for the Enzymatic Synthesis of Novel Protopanaxatriol-Type Ginsenosides
Dai, Longhai,Li, Jiao,Yang, Jiangang,Zhu, Yueming,Men, Yan,Zeng, Yan,Cai, Yi,Dong, Caixia,Dai, Zhubo,Zhang, Xueli,Sun, Yuanxia
, p. 943 - 949 (2018/02/09)
Ginsenosides are the principal bioactive ingredients of Panax ginseng and possess diverse notable pharmacological activities. UDP-glycosyltransferase (UGT)-mediated glycosylation of the C6-OH and C20-OH of protopanaxatriol (PPT) is the prominent biological modification that contributes to the immense structural and functional diversity of PPT-type ginsenosides. In this study, the glycosylation of PPT and PPT-type ginsenosides was achieved using a promiscuous glycosyltransferase (Bs-YjiC) from Bacillus subtilis 168. PPT was selected as the probe for the in vitro glycodiversification of PPT-type ginsenosides using diverse UDP-sugars as sugar donors. Structural analysis of the newly biosynthesized products demonstrated that Bs-YjiC can transfer a glucosyl moiety to the free C3-OH, C6-OH, and C12-OH of PPT. Five PPT-type ginsenosides were biosynthesized, including ginsenoside Rh1 and four unnatural ginsenosides. The present study suggests flexible microbial UGTs play an important role in the enzymatic synthesis of novel ginsenosides.
Synthetic access toward the diverse ginsenosides
Yu, Jun,Sun, Jiansong,Niu, Yiming,Li, Rongyao,Liao, Jinxi,Zhang, Fuyi,Yu, Biao
, p. 3899 - 3905 (2013/09/23)
All the possible types of the protopanaxatriol and protopanaxadiol glycosides, the major active yet extremely heterogeneous principles of ginsengs, could be accessed by the present sequence of transformations, including global removal of the sugar residue
