Draft Genome of Omphalotus olearius Provides a Predictive Framework for Sesquiterpenoid Natural Product Biosynthesis in Basidiomycota

Abstract

SUMMARY The secondary metabolome of Basidiomycota represents a largely uncharacterized source of pharmaceutically relevant natural products. Terpenoids are the primary class of bioactive compounds isolated from mushrooms. The Jack O’Lantern mushroom Omphalotus olearius was identified 50 years ago as a prolific producer of anticancer illudin sesquiterpenoids, however to date there have been exceptionally few studies into the biosynthesis of these important compounds. Here we report the draft genome sequence of O. olearius, which reveals a diverse network of sesquiterpene synthases and two metabolic gene clusters associated with illudin biosynthesis. Their biochemical characterization enabled a comprehensive survey of all currently available Basidiomycota genomes, thereby creating a predictive resource for terpenoid natural product biosynthesis in these organisms. Our results will facilitate discovery and biosynthetic production of unique pharmaceutically relevant bioactive compounds from Basidiomycota.

Lentinula edodes Genome Survey and Postharvest Transcriptome Analysis

“…Lentinula edodes belongs to Marasmiaceae, which includes white rot, saprobic, and plant-pathogenic fungi (34). Plant cell wall-degrading enzymes in Lentinula edodes G408PP-4 (see Table S3) were identical to those of strain W1-26 (16) and similar to other species of Marasmiaceae (Table S3) (35)(36)(37). Characteristically, no lignin peroxidase (Lip)-encoding genes were found in Lentinula edodes or in Marasmiaceae species whose genome sequences are publicly available (Table S3), suggesting that Lentinula edodes lacks Lip and depends on laccases and manganese peroxidases for lignin degradation.…”

Extensive sampling of basidiomycete genomes demonstrates inadequacy of the white-rot/brown-rot paradigm for wood decay fungi

“…Secondary metabolism plays a critical role for fungal survival and success, including Basidiomycota (69), and a rich array of secondary metabolism genes has been reported in Serpula lacrymans and Postia placenta (20), and Omphalotus olearius (70). It may be that secondary metabolites, widely considered to confer advantage by inhibiting competing microorganisms, are more important in the ecological niches occupied by brown-rot fungi, compared with white-rot fungi.…”

Identification of a Fungal 1,8-Cineole Synthase from Hypoxylon sp. with Specificity Determinants in Common with the Plant Synthases

“…This has proven difficult in plants, where TPS sequences are dominated by species relationships rather than product, but the addition of a large number of sequenced fungal and bacterial genomes has reignited these efforts (78). Recent work on terpene synthases from Basidiomycota has attempted to categorize them based on the type of ring closure catalyzed by the enzymes (34,35,79). Most ascomycete terpene synthases in our phylogeny, including those from E7406B, appear distinct from the basidiomycete enzymes as well as plants and bacteria.…”