New Terpendole Congeners, Inhibitors of Sterol O-Acyltransferase, Produced by Volutella citrinella BF-0440

Functional Crosstalk between Discrete Indole Terpenoid Gene Clusters in Tolypocladium album

Indole terpenoids make up a large group of secondary metabolites that display an enticing array of bioactivities. While indole diterpene (IDT) and rarely indole sesquiterpene (IST) pathways have been found individually in filamentous fungi, here we show that both cluster types are encoded within the genome of Tolypocladium album. Through heterologous reconstruction, we demonstrate the SES cluster encodes for IST biosynthesis and can tailor IDT substrates produced by the TER cluster.

The chemical structures and biological activities of indole diterpenoids

Indole diterpenoids (IDTs) are an essential class of structurally diverse fungal secondary metabolites, that generally appear to be restricted to a limited number of fungi, such as Penicillium, Aspergillus, Claviceps, and Epichloe species, etc. These compounds share a typical core structure consisting of a cyclic diterpene skeleton of geranylgeranyl diphosphate (GGPP) and an indole ring moiety derived from indole-3-glycerol phosphate (IGP). 3-geranylgeranylindole (3-GGI) is the common precursor of all IDTs. On this basis, it is modified by cyclization, oxidation, and prenylation to generate a large class of compounds with complex structures. These compounds exhibit antibacterial, anti-insect, and ion channel inhibitory activities. We summarized 204 compounds of IDTs discovered from various fungi over the past 50 years, these compounds were reclassified, and their biological activities were summarized. This review will help to understand the structural diversity of IDTs and provide help for their physiological activities.

The Biosynthesis Related Enzyme, Structure Diversity and Bioactivity Abundance of Indole-Diterpenes: A Review

Indole diterpenes are a large class of secondary metabolites produced by fungi, possessing a cyclic diterpenoid backbone and an indole moiety. Novel structures and important biological activity have made indole diterpenes one of the focuses of synthetic chemists. Although the discovery, identification, structural diversity, biological activity and especially structure–activity relationship of indole diterpenes have been reported in some papers in recent years, they are absent of a systematic and comprehensive analysis, and there is no elucidation of enzymes related to this kind of natural product. Therefore, it is necessary to summarize the relevant reports to provide new perspectives for the following research. In this review, for the first time, the function of related synthases and the structure–activity relationship of indole diterpenes are expounded, and the recent research advances of them are emphasized.

Structures and Biological Activities of Alkaloids Produced by Mushrooms, a Fungal Subgroup

Alkaloids are a wide family of basic N-containing natural products, whose research has revealed bioactive compounds of pharmacological interest. Studies on these compounds have focused more attention on those produced by plants, although other types of organisms have also been proven to synthesize bioactive alkaloids, such as animals, marine organisms, bacteria, and fungi. This review covers the findings of the last 20 years (2002–2022) related to the isolation, structures, and biological activities of the alkaloids produced by mushrooms, a fungal subgroup, and their potential to develop drugs and agrochemicals. In some cases, the synthesis of the reviewed compounds and structure−activity relationship studies have been described.