Characterization of a novel GH10 xylanase with a carbohydrate binding module from Aspergillus sulphureus and its synergistic hydrolysis activity with cellulase

A study was carried out to investigate the characterization of a novel Aspergillus sulphureus JCM01963 xylanase (AS-xyn10A) with a carbohydrate binding module (CBM) and its application in degrading alkali pretreated corncob, rapeseed meal and corn stover alone and in combination with a commercial cellulase. In this study, the 3D structure of AS-xyn10A, which contained a CBM at C-terminal. AS-xyn10A and its CBM-truncated variant (AS-xyn10A-dC) was codon-optimized and over-expressed in Komagaella phaffii X-33 (syn. Pichia pastoris) and characterized with optimal condition at 70 degrees C and pH 5.0, respectively. AS-xyn10A displayed high activity to xylan extracted from corn stover, corncob, and rapeseed meal. The concentration of hydrolyzed xylooligosaccharides (XOSs) reached 1592.26 mu g/mL, 1149.92 mu g/mL, and 621.86 mu g/mL, respectively. Xylobiose was the main product (similar to 70%) in the hydrolysis mixture. AS-xyn10A significantly synergized with cellulase to improve the hydrolysis efficiency of corn stover, corncob, and rapeseed meal to glucose. The degree of synergy (DS) was 1.32, 1.31, and 1.30, respectively. Simultaneously, XOSs hydrolyzed with AS-xyn10A and cellulase was improved by 46.48%, 66.13% and 141.45%, respectively. In addition, CBM variant decreased the yields of xylooligosaccharide and glucose in rapeseed meal degradation. This study provided a novel GH10 endo-xylanase, which has potential applications in hydrolysis of biomass. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

This study investigated a novel endo-xylanase with potential applications in biomass hydrolysis. It was found that the enzyme showed high activity in degrading xylan from various biomass sources and synergized with cellulase to improve hydrolysis efficiency. The study demonstrated the potential of this enzyme in biofuel production.