Purification and characterisation of processive-type endoglucanase and β-glucosidase from Aspergillus ochraceus MTCC 1810 through saccharification of delignified coir pith to glucose

• Published in: Bioresource technology Vol. 213; pp. 245 - 248
• Main Authors: Asha, P., Divya, Jose, Bright Singh, I.S.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.08.2016
• Subjects: Aspergillus ochraceus; Aspergillus ochraceus - enzymology; Aspergillus ochraceus - metabolism; beta-Glucosidase - isolation & purification; beta-Glucosidase - metabolism; Cellulase - isolation & purification; Cellulase - metabolism; Cellulose - metabolism; Delignified coir pith; Fermentation; Fungal Proteins - isolation & purification; Fungal Proteins - metabolism; Glucose; Glucose - metabolism; Lignin - analogs & derivatives; Lignin - chemistry; Lignin - metabolism; Processive endoglucanase; Substrate Specificity; β-Glucosidase; Aspergillus ochraceus; β-Glucosidase; Processive endoglucanase; Glucose; Delignified coir pith
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2016.03.013

•Purification of a new processive-type endoglucanase and β-glucosidase from A. ochraceus.•Cellulases displayed multiple-substrate specificity, processivity and sequential synergy.•Offers a novel and cost effective bioprocess for bioconversion of delignified coir pith to glucose. The study describes purification and characterisation of processive-type endoglucanase and β-glucosidase from Aspergillus ochraceus MTCC 1810 through bioconversion of delignified coir pith to fermentable glucose. The purified processive endoglucanase (AS-HT-Celuz A) and β-glucosidase (AS-HT-Celuz B) were found to have molecular mass of ≈78-kDa and 43-kDa respectively with optimum endoglucanase (35.63U/ml), total cellulase (28.15FPU/ml) and β-glucosidase (15.19U/ml) activities at 40°C/pH 6. The unique feature of AS-HT-Celuz A is the multiple substrate specificity and processivity towards both amorphous and crystalline cellulose. Zymogram indicated both endo and exoglucanase activities residing in different binding sites of a single protein exhibiting sequential synergy with its own β-glucosidase. Accordingly, the identified enzymes could be implemented as synergistic cellulases for complete cellulose saccharification which still considered an unresolved issue in bio-refineries.