Enhanced activity and stability of cellobiase (beta-glucosidase: EC 3.2.1.21) produced in the presence of 2-deoxy-D-glucose from the fungus Termitomyces clypeatus.

In many cases, less glycosylation or deglycosylation adversely affects enzyme activity and stability. When the glycosylation inhibitor 2-deoxy-d-glucose is present in the filamentous fungus Termitomyces clypeatus, an increase in cellobiase production and secretion is early obtained [Mukherjee, S. et al. ; Chowdhury, S]. ; Gorey, S. Pal, S .; Kwala, S Biotechnol. Lett. 2006, 28, 1773 - 1778]. In this study the enzyme was purified from the medium by ultrafiltration and gel permeation, ion exchange and high performance liquid chromatography and its catalytic activity was 6 times higher than that of the control enzyme. K (m) and V (max) of the purified enzyme were determined to be 0.187 mM and 0.018 U mg (-1), respectively, using pNPG as a substrate. The temperature and the optimum pH of the enzyme were 45 ° C. and pH 4, respectively, and remained completely active at a pH range of 5 to 8 and a temperature of 30 to 60 ° C. Interestingly, hypoglycosylated cellobiase is resistant to proteolytic enzymes and endoglycosidases. As protein aggregation increased, it showed higher stability than natural enzyme. This enzyme also showed higher specific activity in the presence of cellobiose and pNPG and was less sensitive to salt and various chemicals. - Glucosidases can be regarded as potentially useful enzymes in various food processing, pharmaceutical and fermentation industries.

Cellulosic materials are the most abundant renewable carbon source in the world. Cellulose can be hydrolyzed using cellulase to produce glucose and glucose can be used to produce ethanol, organic acids and other chemicals. Cellulases are complex enzymes including endoglucanase (EC 3.2.1.4), exoglucanase (EC 3.2.1.91) and cellobiase (EC 3.2.1.21). Hydrolysis of natural cellulose to glucose depends on the synergistic effect of these three components. Trichoderma reese produces the highest cellulase activity and has high endoglucanase and exoglucanase activity, but relatively low cellobiase activity. Therefore, increasing the activity of cellobiase in the cellulase reaction system is the key to increasing the glycation yield of cellulose resources. Aspergillus niger LORRE 012 is a high yield strain for producing cellobiase. The spores of this strain were found to be rich in cellobiase.

In many cases, less glycosylation or deglycosylation adversely affects enzyme activity and stability. When the glycosylation inhibitor 2-deoxy-d-glucose is present in the filamentous fungus Termitomyces clypeatus, an increase in cellobiase production and secretion is early obtained. In this study the enzyme was purified from the medium by ultrafiltration and gel permeation, ion exchange and high performance liquid chromatography and its catalytic activity was 6 times higher than that of the control enzyme. K (m) and V (max) of the purified enzyme were determined to be 0.187 mM and 0.018 U mg (-1), respectively, using pNPG as a substrate. This enzyme also showed higher specific activity in the presence of cellobiose and pNPG and was less sensitive to salt and various chemicals. - Glucosidases can be regarded as potentially useful enzymes in various food processing, pharmaceutical and fermentation industries.

Enhancement of activity and stability of cellobiase (β-glucosidase: EC 3.2.1.21) produced in the presence of fungus Termitomyces clypeatus 2-deoxy-D-glucose