Catalytic promiscuity of O-methyltransferases from Corydalis yanhusuo leading to the structural diversity of benzylisoquinoline alkaloids
Artikel i vetenskaplig tidskrift, 2022

O-methyltransferases play essential roles in producing structural diversity and improving the biological properties of benzylisoquinoline alkaloids (BIAs) in plants. In this study, Corydalis yanhusuo, a plant used in traditional Chinese medicine due to the analgesic effects of its BIA-active compounds, was employed to analyze the catalytic characteristics of O-methyltransferases in the formation of BIA diversity. Seven genes encoding O-methyltransferases were cloned, and functionally characterized using seven potential BIA substrates. Specifically, an O-methyltransferase (CyOMT2) with highly efficient catalytic activity of both 4′- and 6-O-methylations of 1-BIAs was found. CyOMT6 was found to perform two sequential methylations at both 9- and 2-positions of the essential intermediate of tetrahydroprotoberberines, (S)-scoulerine. Two O-methyltransferases (CyOMT5 and CyOMT7) with wide substrate promiscuity were found, with the 2-position of tetrahydroprotoberberines as the preferential catalytic site for CyOMT5 (named scoulerine 2-O-methyltransferase) and the 6-position of 1-BIAs as the preferential site for CyOMT7. In addition, results of integrated phylogenetic molecular docking analysis and site-directed mutation suggested that residues at sites 172, 306, 313, and 314 in CyOMT5 are important for enzyme promiscuity related to O-methylations at the 6- and 7-positions of isoquinoline. Cys at site 253 in CyOMT2 was proved to promote the methylation activity of the 6-position and to expand substrate scopes. This work provides insight into O-methyltransferases in producing BIA diversity in C. yanhusuo and genetic elements for producing BIAs by metabolic engineering and synthetic biology.

Författare

Junling Bu

China Academy of Chinese Medical Sciences

Xiuhua Zhang

China Academy of Chinese Medical Sciences

Qishuang Li

China Academy of Chinese Medical Sciences

Ying Ma

China Academy of Chinese Medical Sciences

Zhimin Hu

China Academy of Chinese Medical Sciences

Jian Yang

China Academy of Chinese Medical Sciences

Xiuyu Liu

Henan University of Chinese Medicine

Ruishan Wang

China Academy of Chinese Medical Sciences

Xiang Jiao

Chalmers, Biologi och bioteknik, Systembiologi

Tong Chen

China Academy of Chinese Medical Sciences

Changjiangsheng Lai

China Academy of Chinese Medical Sciences

Guanghong Cui

China Academy of Chinese Medical Sciences

Jinfu Tang

China Academy of Chinese Medical Sciences

Yu Kong

Shanghai Chenshan Botanical Garden

Lei Yang

Research Center of TCM Information Engineering

Sheng Lin

Research Center of TCM Information Engineering

Yun Chen

Chalmers, Biologi och bioteknik, Systembiologi

Juan Guo

China Academy of Chinese Medical Sciences

Luqi Huang

China Academy of Chinese Medical Sciences

Horticulture Research

26626810 (ISSN) 20527276 (eISSN)

Vol. 9 uhac152

Ämneskategorier

Biokemi och molekylärbiologi

Biokatalys och enzymteknik

Organisk kemi

DOI

10.1093/hr/uhac152

Mer information

Senast uppdaterat

2023-01-09