Functional characterization of flavonoid glycosyltransferase AmGT90 in Astragalus membranaceus.
10.19540/j.cnki.cjcmm.20241215.103
- Author:
Guo-Qing PENG
1
;
Bing-Yan XU
2
;
Jian-Ping HUANG
2
;
Zhi-Yin YU
3
;
Sheng-Xiong HUANG
1
Author Information
1. School of Pharmacy, Chengdu University of Traditional Chinese Medicine Chengdu 611137, China Key Laboratory of Phytochemistry and Natural Medicines, Kunming Institute of Botany,Chinese Academy of Sciences Kunming 650201, China.
2. Key Laboratory of Phytochemistry and Natural Medicines, Kunming Institute of Botany,Chinese Academy of Sciences Kunming 650201, China.
3. Innovative Institute of Chinese Medicine and Pharmacy, Chengdu University of Traditional Chinese Medicine Chengdu 611137, China.
- Publication Type:Journal Article
- Keywords:
Astragalus membranaceus;
UGT74;
flavonoid;
functional characterization;
glycosyltransferase
- MeSH:
Glycosyltransferases/chemistry*;
Flavonoids/chemistry*;
Astragalus propinquus/classification*;
Phylogeny;
Glycosylation;
Plant Proteins/chemistry*;
Substrate Specificity;
Cloning, Molecular;
Amino Acid Sequence
- From:
China Journal of Chinese Materia Medica
2025;50(6):1534-1543
- CountryChina
- Language:Chinese
-
Abstract:
Astragalus membranaceus(A. membranaceus), a traditional tonic, contains flavonoids as one of its main bioactive components and key indicators for quality standard detection. These compounds predominantly exist in glycosylated forms after glycosylation modification within the plant. The catalytic products of flavonoid glycosyltransferases in A. membranaceus have been reported to be mostly monoglycosides, and only AmUGT28 catalyzes luteolin to form diglycosides. In this study, we cloned a glycosyltransferase gene, AmGT90, from A. membranaceus, with an ORF length of 1 335 bp, encoding 444 amino acids, and the protein had a relative molecular mass of 50.5 kDa. Phylogenetic tree analysis indicated that AmGT90 belongs to the UGT74 family. In vitro enzymatic reaction showed that AmGT90 had broad substrate specificity and could catalyze the glycosylation of various flavonoids, including isoflavones, flavones, flavanones, and chalcones. AmGT90 not only catalyzed the formation of monoglycosides but also diglycosides. In addition, the mechanism of AmGT90 catalyzing the formation of diglycosides from luteolin was preliminarily explored. The experimental results showed that AmGT90 may preferentially recognize C4'-OH of luteolin and then recognize C7-OH to form diglycosides. This study reported a glycosyltransferase from A. membranaceus capable of converting flavonoids into monoglycosides and diglycosides. This finding not only enhances our understanding of the biosynthetic pathways of flavonoid glycosides in A. membranaceus but also introduces a new component for glycoside production through synthetic biology.
