Engineering cellulosic ethanol: Surface analysis of cellulose biodegradation

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The objective of this project is to identify critical parameters of substrate structure and chemistry that will provide targets for development of biomass pretreatment and cellulolytic enzymes to be applied to the conversion of biomass to sugars. The results of the research will be of significant value to Iogen Corporation (Canadian company and a world leader in biomass conversion) in their efforts to develop a high efficiency, low cost cellulose ethanol process. The enzymatic conversion step from cellulose to glucose is a principal target for improvement due to the high cost of enzyme manufacture and the recalcitrance of cellulose to hydrolysis. Although chemical and physical pretreatments of lignocellulose are traditional methods for making substrate more susceptible to enzymatic attack, the actual chemical and structural changes occurring are poorly understood. Consequently, the interactions between the substrate and the cellulase enzymes is also a black box. The identification and characterization of both productive and non-productive interactions will provide targets for improvements to both substrate and enzyme. The University research team will employ spectroscopic, surface imaging and surface analytical techniques to better understand:1) What are the rate determining steps of hydrolysis? 2)What are the characteristics of a productive site that an enzyme recognizes for hydrolysis? 3)How can we bias surface sequestration of enzymes to favor binding to productive sites? 4)Do enzymes get stuck and block productive sites? 5) How do enzymes create sites for other enzymes? Our goal is to provide answers to these fundamental questions that provide direction for enzyme and process development. Growing evidence suggests that the bio-based products can be economically competitive alternatives to current, fossil-based feedstocks for energy, chemicals and materials. This is particularly relevant for Canada which has a huge annual production of forest and agricultural biomass. The bio-based economy will have a long term impact on the farming and forestry community. In addition,the development of fuels, chemicals and materials from biomass instead of petroleum will reduce carbon dioxide emission and other GHGs such as nitrous oxide.