Molecular basis of the biosynthesis of pharmacologically active alkaloids from Carolina Jasmine

由于植物能够产生高度多样化且与医学相关的次生代谢物，因此人类已经使用植物数千年了。然而，这种天然产品的工业生产往往非常费力，需要广阔的种植面积，而且生产条件不稳定。这种困境也阻碍了从卡罗莱纳茉莉花（Gelsemium sempervirens）中提取的一组天然产物的使用，这些产物被系统地命名为吲哚生物碱。这些化合物具有抗肿瘤、抗炎、镇痛和抗焦虑活性，但它们在植物中的低产量严重限制了它们的应用。此外，它们复杂的结构阻碍了高效的合成路线。一种有希望的替代方法是通过微生物生物技术生产这些化合物，然而，这需要对这些化合物的潜在生物合成途径有透彻的了解。因此，本研究项目的目的是阐明导致草中氧吲哚生物碱的生物合成步骤。这些信息随后可以转化为微生物生物技术系统，旨在增加这些独特化合物的产量。首先，生物合成基因将根据植物基因组和转录组的序列数据进行鉴定。然后，相关基因产物将在植物中利用病毒诱导的基因沉默和微生物模式生物的生产来表征，这将进一步深入了解不寻常转化的机制。此外，将评估相关基因和酶的定位，例如通过杂交技术或使用荧光显微镜，以更好地了解生物合成途径的空间组织。这些方法近年来已在各种植物中建立起来，从而首次能用现代方法研究Gelsemium生物碱的生物合成。综上所述，这些研究不仅对更好地了解黄绿草中氧吲哚生物合成途径的功能和组织结构具有重要意义，而且为今后利用这些生物碱的药理潜力进行生物技术应用奠定了基础。

Plants have been used by mankind for thousands of years due to their ability to produce highly varied and medicinally relevant secondary metabolites. However, the industrial production of such natural products is often highly laborious, requires vast cultivation areas and suffers from fluctuating production conditions. This dilemma has also hampered the use of a group of natural products from Carolina Jasmine (Gelsemium sempervirens), which are systematically named oxindole alkaloids. These compounds exhibit antitumoral, anti-inflammatory, analgesic and anxiolytic activities, but their low production rates in the plant severely limit their application. Additionally, their complex structures prevent efficient synthetic routes. A promising alternative would be the biotechnological production of these compounds by microorganisms, however, this requires a thorough understanding of the underlying biosynthetic pathway of these compounds. Accordingly, the aim of this research project is the elucidation of the biosynthetic steps leading to the oxindole alkaloids in G. sempervirens. This information can then be later translated to microbial biotechnology systems aimed at the increased production of these unique compounds. To begin with, biosynthetic genes will be identified based on sequence data of the plant genome and transcriptome. Relevant gene products will then be characterized in the plant using virus-induced gene silencing and by production in microbial model organisms, which will give further mechanistic insights of unusual transformations. Additionally, the localization of involved genes and enzymes will be assessed, for example by hybridization techniques or using fluorescence microscopy, to provide a better understanding of the spatial organization of the biosynthetic pathway. All of these methods have been established in various plants in recent years, so that the biosynthesis of the Gelsemium alkaloids can now be studied for the first time with modern methodology. In conclusion, these studies are not only important for a better understanding of the function and organization of the oxindole biosynthetic pathway in G. sempervirens, but also as a basis for future biotechnological applications to harness the pharmacological potential of these alkaloids.