Project description:The ability to obtain carbon and energy is a major requirement to exist in any environment. For several ascomycete fungi (post-)genomic analyses have shown that species that occupy a large variety of habitats possess a diverse enzymatic machinery, while species with a specific habitat have a more focused enzyme repertoire that is well-adapted to the prevailing substrate. White-rot basidiomycete fungi also live in a specific habitat, as they are found exclusively in wood. In this study we evaluated how well the white-rot fungus Dichomitus squalens has adapted to degrade its natural wood substrate. The transcriptome and exoproteome of D. squalens were analysed after cultivation on two natural substrates, aspen and spruce wood, and two non-woody substrates, wheat bran and cotton seed hulls. D. squalens produced ligninolytic enzymes mainly at the early time point of the wood cultures, indicating the need to degrade lignin to get access to wood polysaccharides. Surprisingly, the response of the fungus to the non-woody polysaccharides was nearly as good match to the substrate composition as observed for the wood polysaccharides. This indicates that D. squalens has preserved its ability to efficiently degrade plant polysaccharides not present in its natural habitat.
Project description:Mining of fungal genomes uncovered their great potential for the production of novel secondary metabolites (SMs). However most of them stay silent under standard laboratory cultivation conditions. Co-cultivation of fungi with organism that occur in their natural habitat has shown to be trigger for the activation of such silent SM gene clusters. Recently, we showed that the cultivation of Aspergillus nidulans with the bacterium Streptomyces rapamycinicus leads to the activation of the orsellinic acid gene cluster. Hence we decided to study this interaction further to gain insight into the regulation of SM gene clusters and more specifically to study the chromatin remodelling network actuve upon co-cultivation of the two organisms. This study gives novel insight into the regulation of the orsellinic acid gene cluster and the interaction of the two organisms. To the best of our knowledge this is the first report of mapping the chromatin landscape of microbial interactions, making this study a role model for the analysis of similar systems.