Biochemical and inhibitor analysis of recombinant cellobiohydrolases from Phanerochaete chrysosporium

Author(s)

Oliva, Bianca ; Ferraz, Andre ; Segato, Fernando

• Document type: Journal article
• Source: BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS; v. 17, n. 1, p. 17-pg., 2024-11-29.

Abstract

The demand for greener energy sources necessitates the development of more efficient processes. Lignocellulosic biomass holds significant potential for biofuels production, but improvements in its enzymatic degradation are required to mitigate the susceptibility of enzymes by reaction products and pretreatment impurities. In this work, two cellobiohydrolases (CBHs) from the basidiomycete Phanerochaete chrysosporium (PcCel7C and PcCel7D) were heterologously expressed, characterized, and analyzed in the presence of their products (glucose and cellobiose) and harmful compounds commonly found in industrial processes (phenolics), as well as their adsorption to lignin and cellulose. The enzymes exhibited an optimum temperature of 55 degrees C and displayed a pH profile similar to the model CBHI from Trichoderma reesei (TrCel7A). Activity decreased consistently for all CBHs in the presence of cellobiose, while glucose significantly impacted the basidiomycete CBHs. Phenolic compounds with a higher content of OH groups were found to be more detrimental to the enzymes, with the location of the OH group on the phenolic ring playing a crucial role in enzyme deactivation. Molecular docking simulations predicted that the product-binding site of CBHs has the highest affinity for interaction with phenolics; however, they are unlikely to interact at this site in the presence of substrate. PcCel7C and PcCel7D exhibited poorer adsorption on cellulose compared to the TrCel7A enzyme. These findings provide insights into how the structure of CBHs influences their susceptibility to inhibitors and deactivating compounds present in saccharification reaction medium. (AU)

• FAPESP's process: 14/18714-2 - Enzymatic oxidation of sugarcane bagasse: discovery, characterization and new application of oxidative enzymes active in carbohydrates, applied to the enhancement of a fungal cell factory
• Grantee: Fernando Segato
• Support Opportunities: Program for Research on Bioenergy (BIOEN) - Young Investigators Grants
• FAPESP's process: 22/01756-0 - Biochemical and biophysical analysis of lignin-related compounds effect on the activity of cellobiohydrolases
• Grantee: Bianca Oliva
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• FAPESP's process: 19/06663-8 - Biochemical and functional studies of cellobiohydrolases from basidiomycetes of white-rot fungi with biotechnological potential
• Grantee: Bianca Oliva
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 22/04227-9 - Multiuser equipment granted in the proposal 2021/06679-1: Dionex ICS600 Capillary HPIC system
• Grantee: Fernando Segato
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 21/06679-1 - Enzymatic oxidation of sugarcane bagasse 2: exploring the interaction between LPMOs and its redox partner CDHs aiming for the development of more efficient enzymes for insertion into an engineered cell factory
• Grantee: Fernando Segato
• Support Opportunities: Program for Research on Bioenergy (BIOEN) - Young Investigators Grants - Phase 2
• FAPESP's process: 19/22284-7 - Biochemical, functional characterization and application of polysaccharide lytic monoxygenases identified in transcriptome and secretoma studies of filamentous fungi cultivated in sugarcane bagasse
• Grantee: Fernando Segato
• Support Opportunities: Program for Research on Bioenergy (BIOEN) - Regular Program Grants