Monday, May 4, 2009
5-49
The Improved Cellulosome: Computational Modeling to Minisomes
Yannick J. Bomble1, Michael F. Crowley2, Qi Xu1, Mark R. Nimlos3, Jiancong Xu4, Moumita Saharay4, Hong Guo5, John W. Brady6, David Wilson6, Jeremy C. Smith4, Shi-you Ding7, and Michael E. Himmel7. (1) Biosciences Center,, National Renewable Energy Laboratory, 1617 Cole Blvd, Golden, CO 80401, (2) Chemical and Biosciences Center, National Renewable Energy Laboratory, 1617 Cole Blvd, Golden, CO 80401, (3) National Bioenergy Center, National Renewable Energy Laboratory, 1617 Cole Blvd, Golden, CO 80401, (4) Center for Molecular Biophysics, Oak Ridge National Laboratory, Building 6011, Oakridge, TN 37830, (5) Department of Biochemistry and Cell and Molecular Biology, University of Tennessee, Knoxville, TN 37966, (6) Department of Food Science, Cornell University, Ithaca, NY 14853, (7) Chemical and Biosciences Center,, National Renewable Energy Laboratory, 1617 Cole Blvd, Golden, CO 80401
The first coarse grained model to study the formation and function of the cellulosome was developed within CHARMM. Some of the binding constants between cohesins and dockerins were derived from all-atom simulations. This study aims at understanding the mechanisms involved in the sequential binding of the cellulosomal enzymes on the scaffold of C. thermocellum. Individual subdomains were also studied with CHARMM and Amber on cellulose surfaces or with individual cellulose chains. These domains include, catalytic domains, carbohydrate binding domains, and fibronectins. All five cellulosomal fibronectins (Fn3) of C. thermocellum have been identified, overexpressed and purified, the crystal structure of one of them has been solved, and this provided experimental structure for the computational modeling of cellulosomal Fn3 function.