Protein Engineering of Cellulases to Produce Renewable Energy from Biomass
David B. Wilson and Diana Irwin

Cellulases are enzymes that catalyze the breakdown of cellulose, the most abundant polymer on earth, to the sugar glucose. Cellulose is the structural material of plant cell walls. Although cellulose is cheaper than starch, the cost of hydrolyzing cellulose to glucose currently makes glucose from cellulose more expensive than glucose from starch. Improving enzymes could reduce the cost of hydrolysis. An unusual feature of cellulases is that several different enzymes have to be present together to give the highest rate of cellulose breakdown. One reason for this is that cellulose is insoluble in water so that only the surface of cellulose particles can be broken down.

In this exploration, students will use several different methods to assay cellulase activity and will learn some of the steps in protein chemistry and recombinant DNA that are required to engineer cellulases of higher activity.