Exogenous xylanase expression simultaneously with the indigenous cellulase to increase the cellulose hydrolysis efficiency. (May 2019)

• Record Type: Journal Article
• Authors: Xue, Dongsheng; Jiang, Yanming; Gong, Chunjie
• Is Part Of: International biodeterioration & biodegradation. Volume 140(2019)
• Page Start: 126
• Page End: 132
• Publication Date: 2019-05
• Subjects: Aspergillus niger -- Cellulase -- Xylanase -- Exoglucanase -- Endoglucanase; Biodegradation -- Periodicals; Bioremediation -- Periodicals; Biodegradation -- Periodicals; Biodégradation -- Périodiques; Biorestauration -- Périodiques; Electronic journals; 620.11223
• DOI: 10.1016/j.ibiod.2019.04.003
• Languages: English
• ISSNs: 0964-8305

Abstract

Abstract: To eliminate the xylan steric hindrance to lignocellulosic biomass hydrolysis, a xylanase with exoglucanase and endoglucanase activity was expressed simultaneously with the cellulase in Aspergillus niger . The indigenous coding sequence of the endoglucanase in A . niger was replaced by the encoding xylanase sequence by Agrobacterium mediated transformation. The xylanase was transcribed and translated simultaneously with the indigenous exoglucanase and β-glucosidase. The xylanase activity of the reconstructed A . niger was 3.28 U/mL. The activity of the exoglucanase from the constructed strain was increased to 1.95 U/mL from 0.21 U/mL of the original A . niger . The reconstructed A . niger cellulase could hydrolyze wheat straw to release 19.7 g/L of glucose, compared to 12.01 g/L of that released by the cellullase from the original A . niger . More efficient hydrolysis was achieved by the expression of an exogenous xylanase integrated under the expression regulation system of an indigenous endoglucanase in A . niger . Highlights: A xylanase was integrated under the transcription regulation system of the cellulase. The expressed xylanase enhanced the hydrolysis efficience of the cellulase. The exoglucanase activity was increased to 8.32 U/mL from 0.63 U/mL. The FPA activity was increased to 0.21 U/mL from 1.95 U/mL.