Novel AA9 LPMOs from the thermophilic fungus Thielavia terrestris LPH 172

For making biomass saccharification more efficient, industry is looking into thermophilic microorganisms for production of enzymes with improved thermostability. One such organism is the fungus Thielavia terrestris with alfalfa straw hydrolysis optima around 40 and 60°C (Berka et al., 2011). We isolated the ascomycete T. terrestris strain LPH 172 from compost in Vietnam and fully sequenced its genome. We have also characterized the strain as acidophilic (growing at pH 1) and thermophilic (50°C). High cellulase and xylanase activities at pH 3 and 70°C were also observed. Full genome sequencing revealed 10 128 genes, of which according to dbCAN2 380 encode for putative CAZymes and of those 18 for AA9 LPMOs. We also obtained transcriptomics data from growth on five different substrates: glucose, cellulose (Avicel), beechwood xylan, corncob xylan and rice straw. From differential and absolute gene expression data analysis, we have selected nine putative AA9 LPMO enzymes that showed upregulation on growth on either Avicel or rice straw compared to growth at glucose. For further characterization of these nine AA9s, they will be cloned and produced in Pichia pastoris and analyzed for processing simple and complex biomasses.