SAN DIEGO, April 26 (UPI) -- U.S. scientists are using a supercomputer to produce "virtual molecules" in an effort to improve cellulose conversion into ethanol.
The process of producing ethanol from cellulose is an expensive one, mainly due to the sluggish rate at which the cellulose enzyme complex breaks down tightly bound cellulose into sugars, which are then fermented into ethanol.
To help resolve the problem, a team of scientists conducted molecular simulations at the San Diego Supercomputer Center. By using "virtual molecules," they have discovered key steps in the process by which the enzyme acts as a molecular machine.
To obtain an accurate understanding of the key molecular events required the simulations to run for some 6 million time steps over 12 nanoseconds to capture enough of the motion and shape changes of the enzyme as it interacted with the cellulose surface.
"By learning how the cellulase enzyme complex breaks down cellulose, we can develop protein engineering strategies to speed up this key reaction," said Mike Cleary, a member of the research team.
The research was reported in the April 12 online edition of the Protein Engineering, Design and Selection journal.