Wood-decaying fungi are of special interest in research due to their ability of efficiently degrading wood, the most abundant renewable carbon source on this planet, and their potential for sustainable applications in the production of biofuels and other bioprocesses. For the degradation of wood these organism are using highly specialized sets of secreted enzymes. Here, the secretomes of the brown-rot fungus Fomitopsis pinicola and the white-rot fungus Phanerochaete chrysosporium are studied. These closely related agaricomycetes, are characterized by different preferences regarding their source of nutrients. F. pinicola is using a set of enzymes being specialized for the efficient degradation of cellulose and hemicellulose, whereas P. chrysosporium degrades preferentially lignin.
Investigating fungal cultures on wood gives insights into which carbohydrate-active enzymes are secreted by the fungi in order to degrade their substrates. Limiting the extraction to the extracellular fraction and identifying the enzymes using a proteomic approach, it was possible to verify predicted extracellular enzymes previously only proposed by genomic approaches. Extracellular enzymes could be identified originating from all major enzymatic families involved in the degradation of lignocellulosic biomass (glycoside hydrolases, peroxidases, laccases, hydrolases, lytic polysaccharide monooxygenases, oxidoreductases, glyoxal oxidases, etc.), forming the individual secretome of each of the two investigated fungi.