Biochemical and genetic basis of indole alkaloid formation in the basidiomycete Psilocybe cyanescens

担子菌裸盖菌中吲哚生物碱形成的生化和遗传基础

• 批准号: 318716222
• 负责人: Professor Dr. Dirk Hoffmeister
• 金额: --
• 依托单位: Lehrstuhl für Pharmazeutische Mikrobiologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2016
• 资助国家: 德国
• 起止时间: 2015-12-31 至 2019-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/318716222?language=en
• 关键词: Biochemical; genetic; basis; indole; alkaloid

Filamentous fungi have been recognized as prolific producers of bioactive natural products, among them compounds of great pharmaceutical and commercial value. Prior efforts primarily emphasized research i) on ascomycete products and ii) on such molecules whose backbone is assembled by multimodular enzymes (polyketide synthases, non-ribosomal peptide synthetases), terpene cyclases, or that are made ribosomally. Basidiomycete molecules, and in particular those that do not require the above enzymatic activities, remained very little investigated. Therefore, a bias exists in our understanding of the biosynthetic chemistry behind fungal bioactive small molecule assembly. The proposed research addresses this bias and focuses on one of the rarely explored metabolic pathways that are not based on the above standard biosynthesis enzymes. The objective of this project is to elucidate the indole alkaloid metabolism in the mushroom Psilocybe cyanescens at the enzymatic and genetic level. Species of the genus Psilocybe are colloquially referred to as so-called magic mushrooms as their major metabolites (psilocin and indirectly psilocybin as prodrug) possess psychotropic bioactivity. However, these compounds re-attracted pharmaceutical attention and, thus, are again object of clinical studies. The proposed work serves to understand unusual natural product chemistry, in particular indole hydroxylation at position 4 and phosphoester formation. Psilocybin uniquely combines these structural features. Other bioactive products, including spider venoms, bacterial compounds toxic to plants, and plant metabolites, show these features as well, but individually. Beyond the understanding of psilocybin biosynthesis, this work is therefore expected to have pilot character for natural product research in general. Further, the project lays the foundation for future research on fungal physiology and for forensic applications. Regarding the methodology, its workflow relies on two parallel - yet mutually complementing - lines of research that include i) a biochemical approach to purify native enzymes from the fungus, and ii) on heterologous expression of candidate genes, followed by characterization of the enzymatic activities.

丝状真菌被认为是生物活性天然产物的多产生产者，其中的化合物具有巨大的药用和商业价值。先前的工作主要侧重于i）子囊菌产品和ii）此类分子的研究，这些分子的主链由多模块酶（聚酮合酶、非核糖体肽合成酶）、萜烯环化酶组装而成，或由核糖体制成。担子菌分子，特别是那些不需要上述酶活性的分子，仍然很少被研究。因此，我们对真菌生物活性小分子组装背后的生物合成化学的理解存在偏差。拟议的研究解决了这种偏见，并重点关注一种很少探索的不基于上述标准生物合成酶的代谢途径。该项目的目的是在酶和遗传水平上阐明蘑菇 Psilocybe cynescens 中的吲哚生物碱代谢。裸盖菇属的物种通俗地称为所谓的迷幻蘑菇，因为它们的主要代谢物（裸盖菇素和间接裸盖菇素作为前药）具有治疗精神的生物活性。然而，这些化合物重新引起了药学界的关注，因此再次成为临床研究的对象。拟议的工作旨在了解不寻常的天然产物化学，特别是 4 位吲哚羟基化和磷酸酯的形成。裸盖菇素独特地结合了这些结构特征。其他生物活性产品，包括蜘蛛毒液、对植物有毒的细菌化合物和植物代谢物，也显示出这些特征，但都是单独的。除了对裸盖菇素生物合成的理解之外，这项工作预计对一般天然产物研究具有先导性。此外，该项目为未来真菌生理学和法医学应用的研究奠定了基础。就方法论而言，其工作流程依赖于两条平行但又相互补充的研究路线，其中包括 i) 从真菌中纯化天然酶的生化方法，以及 ii) 候选基因的异源表达，然后对酶活性进行表征。