This Small Business Innovation Research Phase I project is to demonstrate the feasibility of cost-effective conversion of lignocellulosic biomass to sugars. The objective is to analyze expression in transgenic corn of three enzymes that work in concert to digest cellulose to glucose, to enable selection of high-expressing lines to propagate. APPROACH: The genes for cellulases and b-D-glucosidase enzymes are being expressed in corn plants from a seed-preferred promoter (also expresses in callus) and targeted to three sub-cellular locations. Biochemical tools will be developed to analyze expression of the enzymes in transgenic callus tissues. More than 70 transgenic events have been isolated to date. This material has regenerated plants. Lines that express these enzymes at high levels in the seed will be selected for propagation. NON-TECHNICAL SUMMARY: The production of ethanol from lignocellulosic biomass can utilize large volumes of agricultural residues that are untapped today. Ethanol fuels burn cleanly, thus the use of ethanol for partial replacement of petroleum fuels will have a positive impact on the environment. The production of ethanol fuels from lignocellulosic biomass is ready to be developed into a viable industry. These experiments will identify plants that exhibit high expression of cellulases and b-D-glucosidase in transgenic seed. The seed will be used as starting material for a back-cross program to generate plants with acceptable agronomic character. These recombinant enzymes from transgenic maize are an important component of the enablement of the biomass to ethanol process, because maize is a cost-effective production and delivery system for the enzymes.
Keywords: transgenic maize; biomass conversion; cellulose; cellulase; cellulases; lignocellulose; callus; b-d-glucosidase; ethanol
