Publications by authors named "Jascha Volk"

Human drug-metabolizing cytochrome P450 monooxygenases (CYPs) have enormous substrate promiscuity; this makes them promising tools for the expansion of natural product diversity. Here, we used CYP3A4 for the targeted diversification of a plant biosynthetic route leading to monoterpenoid indole alkaloids. In silico, in vitro and in planta studies proved that CYP3A4 was able to convert the indole alkaloid vinorine into vomilenine, the former being one of the central intermediates in the ajmaline pathway in the medicinal plant Rauvolfia serpentina (L.

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Two newly identified phytohormone cleaving esterases from Olea europaea are responsible for the glucosidase-initiated activation of the specialized metabolites ligstroside and oleuropein. Biosynthetic routes leading to the formation of plant natural products are tightly orchestrated enzymatic sequences usually involving numerous specialized catalysts. After their accumulation in plant cells and tissues, otherwise non-reactive compounds can be enzymatically activated, e.

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Objective: Through heterologous expression of the tetrahydrocannabinolic acid synthase (THCAS) coding sequence from Cannabis sativa L. in Nicotiana benthamiana, we evaluated a transient plant-based expression system for the production of enzymes involved in cannabinoid biosynthesis.

Results: Thcas was modularized according to the GoldenBraid grammar and its expression tested upon alternative subcellular localization of the encoded catalyst with and without fusion to a fluorescent protein.

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Based on findings described herein, we contend that the reduction of vomilenine en route to antiarrhythmic ajmaline in planta might proceed via an alternative, novel sequence of biosynthetic steps. In the genus Rauvolfia, monoterpenoid indole alkaloids (MIAs) are formed via complex biosynthetic sequences. Despite the wealth of information about the biochemistry and molecular genetics underlying these processes, many reaction steps involving oxygenases and oxidoreductases are still elusive.

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