Tremorgenic Mycotoxins: Structure Diversity and Biological Activity

Area of Science:

• Mycology
• Natural Product Chemistry
• Biochemistry

Background:

• Indole-diterpenes are unique fungal metabolites, with specific compounds like lolitrems and penitrem produced by distinct fungal genera (e.g., *Epichloë*, *Penicillium*, *Aspergillus*).
• These fungi often associate with pasture grasses, and their indole-diterpene products can induce toxicity in grazing livestock.
• The structural diversity of indole-diterpenes is significant, leading to varied biological activities even among related compounds.

Purpose of the Study:

• To review the structural variations and subgroups of indole-diterpenes.
• To document the unique biological activities associated with these compounds.
• To highlight the agricultural and pharmaceutical relevance of indole-diterpenes.

Main Methods:

• Literature review of indole-diterpene research.
• Analysis of structural classifications including paspaline, paxilline, shearinines, paspalitrems, terpendoles, penitrems, lolitrems, janthitrems, and sulpinines.
• Examination of biosynthetic origins from geranylgeranyl diphosphate (GGPP) and tryptophan.

Main Results:

• Indole-diterpenes are produced by Eurotiomycetes and Sordariomycetes fungi.
• Structural diversity arises from enzymatic modifications of a common core derived from GGPP and tryptophan.
• Structurally related indole-diterpenes exhibit distinct biological activities.

Conclusions:

• Indole-diterpenes represent a versatile class of fungal metabolites with significant structural diversity.
• Their varied biological activities underscore their importance in ecological interactions and potential for agricultural and pharmaceutical development.
• Understanding indole-diterpene biosynthesis and structure-activity relationships is crucial for harnessing their potential.