Bioprospecting of Thermostable Cellulolytic Enzymes through Modeling and Virtual Screening Method

Abstract

Cellulolytic enzymes are promising candidates for the use of cellulose in any bioprocess operations and for the disposal of the cellulosic wastes in an environmentally benign manner. Cellulases from thermophiles have the advantage of hydrolyzing cellulose at wider range of operating conditions unlike the normal enzymes. Herein we report the modeled structures of cellulolytic enzymes (endoglucanase, cellobiohydrolase and β-glucosidase) from a thermophilic bacterium, Clostridium thermocellum and their validation using Root Mean Square Deviation (RMSD) and Ramachandran plot analyses. Further, the molecular interactions of the modeled enzyme with cellulose were analyzed using molecular docking technique. The results of molecular docking showed that the endoglucanase, cellobiohydrolase and β-glucosidase had the binding affinities of -10.7, -9.0 and -10.8 kcal/mol, respectively. A correlation between the binding affinity of the endoglucanase with cellulose and the enzyme activity was also demonstrated. The results showed that the binding affinities of cellulases with cellulose could be used as a tool to assess the hydrolytic activity of cellulases. The results obtained could be used in virtual screening of cellulolytic enzymes based on the molecular interactions with the substrate, and aid in developing systems biology models of thermophiles for industrial biotechnology applications.

An overview of biomass conversion: exploring new opportunities

“…The hydrolytic activity of cellulases depends mostly on the binding affinities of the enzyme with cellulose (Krishnaraj et al, 2017). These results were obtained by molecular docking and this method is useful in industrial biotechnology to design more effective enzyme structures (Amore et al, 2017).…”

In silico studies on structural, functional, and evolutionary analysis of bacterial chromate reductase family responsible for high chromate bioremediation efficiency

“…Enzymes and its activity can be investigated in a simple manner and in a shorter time with the help of In silico study, whereas experimental techniques are laborious, time-consuming, and also demand sophisticated and expensive infrastructures [20]. In silico structure-based study of proteins has now been widely and most frequently used in modern scientific world along with both the in vitro and in vivo experimental works.…”