Comparative Genomics Across Ganoderma Species to Identify Secondary Metabolite Clusters with Cytoxic Properties

Comparative Genomics Across Ganoderma Species to Identify Secondary Metabolite Clusters with Cytoxic Properties

Alvin Sherman Library

Fungi in the genus Ganoderma have been widely studied in Chinese culture for their medicinal properties and promoting overall health and longevity. Our prior work on eight Ganoderma species showed that they contain Secondary Metabolite Clusters (SMCs) that code for multiple terpenes, betalactones, and ribosomally synthesized and post-translationally modified peptides (RiPPs). These compounds are well known for their cytotoxic and anticancer potential. A specialized bioinformatics analysis tool, antiSMASH1, was used to identify and annotate SMCs that produce anticancer compounds in the eight Ganoderma genomes. To test the results obtained from the bioinformatics analysis, fungal extracts were prepared from G. lucidum and G. tsugae by air-drying and powdering the mushroom fruiting bodies, mixing them with 95% ethanol, followed by lyophilization. Different dilutions of these extracts are being used for proliferation assays on four cancer cell lines, PN528, PN84 (Proneural) and patient-derived GSC17, GSC20 (Glioblastoma stem cells) to assess the cytotoxicity potential of the fungal compounds. Cell counts will be performed along with the assessment of stem cell and apoptotic markers, with the expectation that stem cell markers will decrease and apoptotic markers will increase in treated cells. Survival analysis will be performed to evaluate and compare the survival rates of cells over time. In addition, comparative transcriptomic analyses will be performed to identify differentially expressed genes/pathways followed by qRT-PCR. The promise of this study lies in establishing the pharmaceutical and nutritional role of natural products from the genus Ganoderma and creating opportunities to develop market-ready health products.