Heterologous expression of cytotoxic sesquiterpenoids from the medicinal mushroom Lignosus rhinocerotis in yeast

• Published in: Microbial cell factories 2017-06, Vol.16 (1), p.103-103, Article 103
• Main Authors: Yap, Hui-Yeng Yeannie, Muria-Gonzalez, Mariano Jordi, Kong, Boon-Hong, Stubbs, Keith A, Tan, Chon-Seng, Ng, Szu-Ting, Tan, Nget-Hong, Solomon, Peter S, Fung, Shin-Yee, Chooi, Yit-Heng
• Format: Article
• Language: English
• Subjects: (+)-Torreyol; Adenocarcinoma; Agaricales - chemistry; Agaricales - genetics; Alcohols; Alkyl and Aryl Transferases - genetics; Alkyl and Aryl Transferases - metabolism; Antimicrobial agents; Antineoplastic Agents - chemistry; Antineoplastic Agents - metabolism; Antineoplastic Agents - pharmacology; Basidiocarps; Basidiomycota; Bioactive compounds; Biocompatibility; Biosynthesis; Biotechnology; Cancer; Cell culture; Cell Line, Tumor; Cell Survival - drug effects; Chemical synthesis; Cloning; Cubebene; Cytochrome; Cytotoxicity; Deoxyribonucleic acid; DNA; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Enzymes; Gene expression; Genes; Genetic aspects; Genomes; Germacrene; Humans; Laboratories; Lignosus rhinocerotis; Metabolism; Metabolites; Molecular Structure; Mushrooms; NMR; Nuclear magnetic resonance; Oils & fats; Phylogeny; Physiological aspects; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae - metabolism; Sesquiterpene synthase; Sesquiterpenes; Sesquiterpenes - chemistry; Sesquiterpenes - metabolism; Sesquiterpenes - pharmacology; Sesquiterpenoid; Sesquiterpenoids; Stereoisomers; Structure-Activity Relationship; Tiger milk mushroom; Toxicity; Tropical diseases; Tumor cell lines; Yeast; α-Cadinol
• ISSN: 1475-2859; 1475-2859
• DOI: 10.1186/s12934-017-0713-x

Genome mining facilitated by heterologous systems is an emerging approach to access the chemical diversity encoded in basidiomycete genomes. In this study, three sesquiterpene synthase genes, GME3634, GME3638, and GME9210, which were highly expressed in the sclerotium of the medicinal mushroom Lignosus rhinocerotis, were cloned and heterologously expressed in a yeast system. Metabolite profile analysis of the yeast culture extracts by GC-MS showed the production of several sesquiterpene alcohols (C H O), including cadinols and germacrene D-4-ol as major products. Other detected sesquiterpenes include selina-6-en-4-ol, β-elemene, β-cubebene, and cedrene. Two purified major compounds namely (+)-torreyol and α-cadinol synthesised by GME3638 and GME3634 respectively, are stereoisomers and their chemical structures were confirmed by H and C NMR. Phylogenetic analysis revealed that GME3638 and GME3634 are a pair of orthologues, and are grouped together with terpene synthases that synthesise cadinenes and related sesquiterpenes. (+)-Torreyol and α-cadinol were tested against a panel of human cancer cell lines and the latter was found to exhibit selective potent cytotoxicity in breast adenocarcinoma cells (MCF7) with IC value of 3.5 ± 0.58 μg/ml while α-cadinol is less active (IC  = 18.0 ± 3.27 μg/ml). This demonstrates that yeast-based genome mining, guided by transcriptomics, is a promising approach for uncovering bioactive compounds from medicinal mushrooms.