Bioprospecting of Thermostable Cellulolytic Enzymes through Modeling and Virtual Screening Method

  1. R. Navanietha Krishnaraj1,2,
  2. Dipayan Samanta1,
  3. Anand Kumar1,
  4. Rajesh Sani2*

Author Affiliations

  • 1Department of Biotechnology, National Institute of Technology Durgapur, Mahatma Gandhi Avenue, Durgapur 713209, INDIA
  • 2Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City 57701, USA

Can J Biotech, Volume 1, Issue 1, Pages 19-25, DOI: 10.24870/cjb.2017-000105

Received: Feb 13, 2017; Revised: Mar 15, 2017; Accepted: Mar 20, 2017


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 -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 -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.


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