Heterologous expression and functional characterization of a GH10 endoxylanase from Aspergillus fumigatus var. niveus with potential biotechnological application

Authors

• Josman Velasco, University of Sao Paulo, Brazil
• Bianca Oliva, University of Sao Paulo, Brazil
• Evandro Jose Mulinari, University of Sao Paulo, Brazil
• Leidy Patricia Quintero, University of Sao Paulo, Brazil
• Awana da Silva Lima, University of Sao Paulo, Brazil
• Aline Larissa Goncalves, University of Sao Paulo, Brazil
• Thiago Augusto Goncalves, University of Campinas, Brazil
• Andre Damasio, University of Campinas, Brazil
• Fabio Marcio Squina, University of Campinas, Brazil
• Adriane Maria Ferreira Milagres, University of Sao Paulo, Brazil
• Asmaa Abdella, University of Nebraska - Lincoln
• Mark R. Wilkins, University of Nebraska - LincolnFollow
• Fernando Segato, University of Sao Paulo, BrazilFollow

Document Type

Article

Date of this Version

2019

Citation

Biotechnology Reports 24 (2019) e00382

Comments

© 2019 The Authors.

Open access

https://doi.org/10.1016/j.btre.2019.e00382

Abstract

Xylanases decrease the xylan content in pretreated biomass releasing it from hemicellulose, thus improving the accessibility of cellulose for cellulases. In this work, an endo-β-1,4-xylanase from Aspergillus fumigatus var. niveus (AFUMN-GH10) was successfully expressed. The structural analysis and biochemical characterization showed this AFUMN-GH10 does not contain a carbohydrate-binding module. The enzyme retained its activity in a pH range from 4.5 to 7.0, with an optimal temperature at 60°C. AFUMN-GH10 showed the highest activity in beechwood xylan. The mode of action of AFUMNGH10 was investigated by hydrolysis of APTS-labeled xylohexaose, which resulted in xylotriose and xylobiose as the main products. AFUMN-GH10 released 27% of residual xylan from hydrothermally-pretreated corn stover and 14% of residual xylan from hydrothermally-pretreated sugarcane bagasse. The results showed that environmentally friendly pretreatment followed by enzymatic hydrolysis with AFUMN-GH10 in low concentration is a suitable method to remove part of residual and recalcitrant hemicellulose from biomass.