Investigation into the bioactive metabolites of deep sea fungi

Eleven fungal strains were cultured from deep sea samples collected from Irish waters. The crude organic extracts of the fungi were initially tested for bioactivity against gram negative bacteria such as Escherichia coli and Pseudomonas aeruginosa, as well as gram positive bacteria such as Staphylococcus aureus and Bacillus subtilis. In an attempt to increase the production of bioactive secondary metabolites epigenetic modifiers, capable of activating silenced or attenuated gene clusters in the fungi, were employed. Each of the fungal strains were exposed to two such epigenetic modifiers, namely sodium butyrate and 5-azacytidine, inhibiting histone deacetylase (HDAC) and DNA methyltransferase (DNMT) respectively. The effects of these epigenetic modifications on the bioactivity of the resulting fungal extracts were determined through a range of biological assays. Comparative investigations of the metabolomic profiles produced by fungal strains were conducted using LC-MS as well as NMR spectroscopy to establish any resultant changes in the bioactive secondary metabolites brought about through the epigenetic modification.