Screening the tropical fungal biodiversity of Vietnam for biomass modifying enzymes, with secretome and transcriptome analyses

In the bio-based economy concept, the current hydrocarbon fuels and non-biodegradable plastics will be replaced by new products which will derive from natural and renewable resources. The synthesis of such biofuels and biochemicals is still challenged by the difficulties to cost efficiently degrade lignocellulosic materials to fermentable sugars or to isolate the intact polymers. Biomass degrading and modifying enzymes play an integral role both in the separation of the polymers from the wood network, as well as in subsequent modifications, prior to further product development. The type of application usually defines the conditions where the reactions should take place. Thus, novel enzymes with variable combined properties, such as different thermotolerance, pH range of activity, substrate specificity and solvent tolerance, still need to be discovered and developed to achieve the highest possible efficiency in each occasion. We took advantage of the rapidly evolving and high biodiversity of the tropics and have been screening various isolates for their cellulases and hemicellulases activities. Promising strains were then cultivated in bioreactors with different carbon sources, such as wheat bran, spruce and avicel and their biomass degrading capacity was analysed through cross species protein identification of their secretome with TMT. Information on the genes involved in the different stages of the fermentation and the carbon source will be acquired with next generation sequencing of the total transcriptome. Interesting transcripts will then be used to heterologously clone and express the respective genes and identify their role in the degradation process