Development of Novel Proteins to Enhance Cellulose Deconstruction for Ethanol Production

Fuels derived from cellulosic biomass offer an alternative to conventional energy sources that supports national economic growth, national energy security, and environmental goals. In the 2007 State of the Union address, President Bush called for 35 billion gallons of alternative fuel use in the United States by 2017, which would replace 20 percent of the nation¿s petroleum consumption. Cellulosic biomass is an attractive energy feedstock because supplies are abundant domestically and globally. Current methods to break down biomass into simple sugars and convert them into ethanol are inefficient and constitute the core barrier to producing ethanol at volumes and costs competitive with gasoline. This project seeks to demonstrate the feasibility of the use of a novel plant protein, HED2, to improve the performance of enzymes in the deconstruction of cellulosic biomass. Preliminary experimentation indicated that HED2 proteins act synergistically with cellulose in the hydrolysis of crystalline cellulose. Expansyn Technologies objective for Phase I will focus on producing gram-scale levels of recombinant Zea m3 (ZM3), a maize HED2, and comprehensive testing of the recombinant protein for cellulose synergism with various forms of cellulose and cellulosic biomass. Once feasibility of the HED2 protein has been demonstrated, Expansyn Technologies will follow up with a Phase II proposal in which the synthesis and use of the protein will be demonstrated at a pilot scale. This technology has the potential to dramatically improve the digestibility of cellulosic feedstocks, thereby enabling commercial-scale production and use of an alternative fuel from renewable resources while reducing greenhouse gas emissions.