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Background Wood-decay basidiomycetes are effective for the degradation of highly lignified and recalcitrant plant substrates. The degradation of lignocellulosic materials by brown-rot strains is carried out by carbohydrate-active enzymes and non-enzymatic Fenton mechanism. Differences in the lignocellulose catabolism among closely related brown rots are not completely understood. Here, a multi-omics approach provided a global understanding of the strategies employed by L. sulphureus ATCC 52600 for lignocellulose degradation. Results The genome of Laetiporus sulphureus ATCC 52600 was sequenced and phylogenomic analysis supported monophyletic clades for the Order Polyporales and classification of this species within the family Laetiporaceae. Additionally, the plasticity of its metabolism was revealed in growth analysis on mono- and disaccharides, and polysaccharides such as cellulose, hemicelluloses, and polygalacturonic acid. The response of this fungus to the presence of lignocellulosic substrates was analyzed by transcriptomics and proteomics and evidenced the occurrence of an integrated oxidative–hydrolytic metabolism. The transcriptomic profile in response to a short cultivation period on sugarcane bagasse revealed 125 upregulated transcripts, which included CAZymes (redox enzymes and hemicellulases) as well as non-CAZy redox enzymes and genes related to the synthesis of low-molecular-weight compounds. The exoproteome produced in response to extended cultivation time on Avicel, and steam-exploded sugarcane bagasse, sugarcane straw, and Eucalyptus revealed 112 proteins. Contrasting with the mainly oxidative profile observed in the transcriptome, the secretomes showed a diverse hydrolytic repertoire including constitutive cellulases and hemicellulases, in addition to 19 upregulated CAZymes. The secretome induced for 7 days on sugarcane bagasse, representative of the late response, was applied in the saccharification of hydrothermally pretreated grass (sugarcane straw) and softwood (pine) by supplementing a commercial cocktail. Conclusion This study shows the singularity of L. sulphureus ATCC 52600 compared to other Polyporales brown rots, regarding the presence of cellobiohydrolase and peroxidase class II. The multi-omics analysis reinforces the oxidative–hydrolytic metabolism involved in lignocellulose deconstruction, providing insights into the overall mechanisms as well as specific proteins of each step.

Fungal lytic polysaccharide monooxygenases (LPMOs) are copper-dependent enzymes that boost plant biomass degradation in combination with glycoside hydrolases. Secretion of LPMO9s arsenal by Aspergillus nidulans is influenced by the substrate and time of induction.

Pectin hydrolysis by recombinant ABNase plays a role in the effective application of enzymatic cocktails for biomass saccharification.

Background: Wood-decay basidiomycetes are effective for the degradation of highly lignified and recalcitrant substrates. Brown-rot strains produce carbohydrate-active enzymes involved in the degradation of lignocellulosic materials, along with a non-enzymatic mechanism via Fenton reaction. Differences in the lignocellulose metabolism among closely related brown rots are not completely understood. Here, a multi-omics approach provided a global understanding of the strategies employed by L. sulphureus ATCC 52600 in the degradation of lignocellulosic by-products derived from sugarcane and Eucalyptus. Results: To evidence the oxidative-hydrolytic mechanism, the Laetiporus sulphureus ATCC 52600 genome was sequenced and the response to lignocellulosic substrates was analyzed by transcriptomics and proteomics. The transcriptomic profile in response to a short cultivation period on in natura sugarcane bagasse revealed 128 out of 12,802 upregulated transcripts. The high upregulated transcripts included a set of redox enzymes along with hemicellulases. The exoproteome produced in response to extended time cultivation on Avicel, and steam-exploded sugarcane bagasse, sugarcane straw, and Eucalyptus (from Eucalyptus grandis) revealed 121 proteins. Contrasting with the mainly oxidative profile observed in the transcriptome, the secretomes showed a diverse hydrolytic repertoire including constitutive cellulases and hemicellulases, in addition to 19 upregulated proteins relative to glucose. The secretome produced on sugarcane bagasse was evaluated in the saccharification of pretreated sugarcane straw by supplementing a commercial cocktail. Additionally, growth analysis revealed that L. sulphureus ATCC 52600 has higher efficiency to assimilate glucose than other mono- and disaccharides.Conclusion: This study shows the singularity of L. sulphureus ATCC 52600 compared to other Polyporales brown rots, regarding the presence of cellobiohydrolase and peroxidase class II. The multi-omics analysis reinforces the oxidative-hydrolytic metabolism involved in lignocellulose deconstruction, providing insights into the overall mechanisms as well as specific proteins of each step.