Metabolic profile analysis in Penicillium brasilianum fungus pre and post-histone deacetylase gene deletion

Abstract

The fungus Penicillium brasilianum, isolated as endophytic of Melia azedarach, presents a great potential of bioactive secondary metabolites production as verified in functional analyzes of the genome of this microorganism. The fungus Penicillium brasilianum had its genome recently sequenced and the final assembly revealed 252 supercontigs which were subjected to genetic prediction and automatic annotation. Functional analyzes of the genome revealed 69 possible biosynthetic clusters, with 11 clusters related to biosynthesis of potential polyketide compounds via PKS (polyketide synthase) enzymes; 12 different clusters involved in the production of secondary metabolites formed via NRPS-like enzymes (non-ribosomal peptide synthetases) and 6 hybrid biosynthetic clusters, among them the NRPS-terpene hybrid responsible for alkaloid biosynthesis, indicating the great potential of this organism to produce bioactive secondary metabolites. The genes that encode the production of these metabolites are clustered, in other words, groups of biosynthetic genes that participate in the same metabolic pathway. However, in standard laboratory cultivation conditions, we often cannot access these natural products, since most of these biosynthetic clusters are silenced. One of the approaches used to promote the activation of these gene clusters is the alteration of the chromatin configuration since it is an important regulator of gene expression in eukaryotic organisms. The deletion of the HdaA gene, which codes for the histone deacetylase enzymes, increases the availability of the DNA strand for transcription and can activate previously silenced gene clusters. In this project, we aimed the deletion of the HdaA gene of the P. brasilianum fungus, as a strategy to activate the production of secondary metabolites and, in this way, to promote the diversity of natural products. The deletion will be conducted from the construction of a deletion cassette for the HdaA gene using in vivo homologous recombination system in S. cerevisiae. The material will be purified and used in the wild-type transformation reactions for the production of the mutant strains. After confirmation of the mutant obtained from molecular techniques, the wild-type and mutant metabolic profile will be compared by LC-MS-MS techniques and later characterization of possible metabolites induced by 1D and 2D NMR.