Lignocellulose depolymerization occurs via an environmentally adapted metabolic cascades in the wood-rotting basidiomycete Phanerochaete chrysosporium

Abstract

Plant biomass can be utilized by a lignocellulose-degrading fungus, Phanerochaete chrysosporium, but the metabolic and regulatory mechanisms involved are not well understood. A polyomics-based analysis (metabolomics, proteomics, and transcriptomics) of P. chrysosporium has been carried out using statistically optimized conditions for lignocellulolytic reaction. Thirty-nine metabolites and 123 genes (14 encoded proteins) that consistently exhibited altered regulation patterns were identified. These factors were then integrated into a comprehensive map that fully depicts all signaling cascades involved in P. chrysosporium. Despite the diversity of these cascades, they showed complementary interconnection among themselves, ensuring the efficiency of passive biosystem and thereby yielding energy expenditure for the cells. Particularly, many factors related to intracellular regulatory networks showed compensating activity in homeostatic lignocellulolysis. In the main platform of proactive biosystem, although several deconstruction-related targets (e.g., glycoside hydrolase, ureidoglycolate hydrolase, transporters, and peroxidases) were systematically utilized, well-known supporters (e.g., cellobiose dehydrogenase and ferroxidase) were rarely generated. Recalcitrant plant biomass can be efficiently utilized by a lignocellulose-degrading fungus, Phanerochaete chrysosporium, but the regulatory and metabolic mechanisms involved are not well understood. Elucidation of the self-regulated system in P. chrysosporium is important for the enhanced utilization of renewable biomass in biorefineries for the production of chemicals and fuels. This study is the first to evaluate the interconnected lignocellulolytic networks of P. chrysosporium based on combined multi-omics approach with target optimization.