| 1. |
- Bu, Junling, et al.
(författare)
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Catalytic promiscuity of O-methyltransferases from Corydalis yanhusuo leading to the structural diversity of benzylisoquinoline alkaloids
- 2022
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Ingår i: Horticulture Research. - : Oxford University Press (OUP). - 2662-6810 .- 2052-7276. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- 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.
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| 2. |
- Coscieme, Luca, et al.
(författare)
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Multiple conceptualizations of nature are key to inclusivity and legitimacy in global environmental governance
- 2020
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Ingår i: Environmental Science and Policy. - : Elsevier BV. - 1462-9011 .- 1873-6416. ; 104, s. 36-42
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Tidskriftsartikel (refereegranskat)abstract
- Despite increasing scientific understanding of the global environmental crisis, we struggle to adopt the policies science suggests would be effective. One of the reasons for that is the lack of inclusive engagement and dialogue among a wide range of different actors. Furthermore, there is a lack of consideration of differences between languages, worldviews and cultures. In this paper, we propose that engagement across the science-policy interface can be strengthened by being mindful of the breadth and depth of the diverse human-nature relations found around the globe. By examining diverse conceptualizations of nature in more than 60 languages, we identify three clusters: inclusive conceptualizations where humans are viewed as an integral component of nature; non-inclusive conceptualizations where humans are separate from nature; and deifying conceptualizations where nature is understood and experienced within a spiritual dimension. Considering and respecting this rich repertoire of ways of describing, thinking about and relating to nature can help us communicate in ways that resonate across cultures and worldviews. This repertoire also provides a resource we can draw on when defining policies and sustainability scenarios for the future, offering opportunities for finding solutions to global environmental challenges.
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