Affiliation:
1. Academician Workstation, Research Center for Differentiation and Development of TCM Basic Theory, Jiangxi University of Chinese Medicine, Nanchang 330004, China
2. State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs, National Resource Center for Chinese Materia Medica, Chinese Academy of Chinese Medical Sciences, Beijing 100700, China
Abstract
Safflower (Carthamus tinctorius L.) has been recognized for its medicinal value, but there have been limited studies on the glycosyltransferases involved in the biosynthesis of flavonoid glycosides from safflower. In this research, we identified two highly efficient flavonoid O-glycosyltransferases, CtOGT1 and CtOGT2, from safflower performing local BLAST alignment. By constructing a prokaryotic expression vector, we conducted in vitro enzymatic reactions and discovered that these enzymes were capable of catalyzing two-step O-glycosylation using substrates such as kaempferol, quercetin, and eriodictyol. Moreover, they exhibited efficient catalytic activity towards various compounds, including flavones (apigenin, scutellarein), dihydrochalcone (phloretin), isoflavones (genistein, daidzein), flavanones (naringenin, glycyrrhizin), and flavanonols (dihydrokaempferol), leading to the formation of O-glycosides. The broad substrate specificity of these enzymes is noteworthy. This study provides valuable insights into the biosynthetic pathways of flavonoid glycosides in safflower. The discovery of CtOGT1 and CtOGT2 enhances our understanding of the enzymatic processes involved in synthesizing flavonoid glycosides in safflower, contributing to the overall comprehension of secondary metabolite biosynthesis in this plant species.
Funder
China Academy of Chinese Medical Sciences
Fundamental Research Funds of the China Academy of Chinese Medical Sciences
Key project at central government level: The establishment of sustainable use for valuable Chinese medicine resources
Subject
Chemistry (miscellaneous),Analytical Chemistry,Organic Chemistry,Physical and Theoretical Chemistry,Molecular Medicine,Drug Discovery,Pharmaceutical Science