Expanding the diversity of plant monoterpenoid indole alkaloids employing human cytochrome P450 3A4.

Human drug-metabolizing cytochrome P450 monooxygenases (CYPs) feature enormous substrate promiscuity, making them promising tools for the expansion of natural product diversity. Here, we utilized 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.) Benth. ex Kurz. However, to a much larger extent, the investigated conversion yielded vinorine (19 R , 20 R) -epoxide, a new metabolite containing an epoxide functional group that is rare for indole alkaloids. The described work represents a successful example of combinatorial biosynthesis towards an increase in biodiversity of natural metabolites. Besides, characterisation of the products of in vitro and in planta transformation of potential pharmaceuticals with human CYPs might be indicative of the way of their conversion in the human organism