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

几千年来，植物一直被人类利用，因为它们能够产生高度多样化和医学上相关的次生代谢物。然而，这种天然产物的工业化生产往往劳动强度高，需要广阔的种植面积，生产条件也不稳定。这一两难境地也阻碍了一组来自卡罗莱纳茉莉花的天然产物的使用，这些天然产物被系统地命名为氧化吲哚生物碱。这些化合物具有抗肿瘤、抗炎、镇痛和抗焦虑等活性，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有效的合成路线。一种有希望的替代方案是由微生物通过生物技术生产这些化合物，然而，这需要彻底了解这些化合物的潜在生物合成途径。因此，本研究项目的目的是阐明导致紫云英中氧化吲哚生物碱的生物合成步骤。这些信息随后可以被转化为微生物生物技术系统，目的是增加这些独特化合物的生产。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识别。然后，相关的基因产物将在植物中使用病毒诱导的基因沉默来表征，并通过在微生物模式生物中的生产来表征，这将给出对不寻常转变的进一步的机械洞察。此外，还将评估所涉及的基因和酶的定位，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。近年来，所有这些方法都已在各种植物中建立，因此现在可以首次用现代方法研究钩吻生物碱的生物合成。综上所述，这些研究不仅对于更好地理解氧化吲哚生物合成途径的功能和组织具有重要意义，而且也是未来生物技术应用的基础，以利用这些生物碱的药理潜力。

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.