January 2014 – Enhancing cellulose utilization for fuels and chemicals by genetic modification of plant cell wall architecture
Cellulose from plant biomass can serve as a sustainable feedstock for fuels, chemicals and polymers that are currently produced from petroleum. In order to enhance economic feasibility, the efficiency of cell wall deconstruction needs to be enhanced. With the use of genetic and biotechnological approaches cell wall composition can be modified in such a way that interactions between the major cell wall polymers — cellulose, hemicellulosic polysaccharides and lignin — are altered. Some of the resulting plants are compromised in their growth and development, but this may be caused in part by the plant’s overcompensation for metabolic perturbances. In other cases novel structures have been introduced in the cell wall without negative effects. The first field studies with engineered bioenergy crops look promising, while detailed structural analyses of cellulose synthase offer new opportunities to modify cellulose itself.
Learn more about Dr. Wilfred Vermerris!
Department of Microbiology and Cell Science University of Florida
Description of Research
Research in Dr. Vermerris’ lab is focused on improving crops that can be used for the production of renewable fuels and chemicals. We use genetic approaches to not only improve the performance and yield of the crop, but also the bioprocessing characteristics and properties of the materials that can be produced from plant biomass. Our main focus is on sweet sorghum, a tall (12-15 ft) grass that performs well in warm and dry climates. Several biorefineries in Florida plan to use sweet sorghum as a feedstock for fuels and chemicals, by extracting the juice and fermenting the sugars. Sweet sorghum has traditionally not been produced on a large scale in Florida, and there is a need for new cultivars and varieties adapted to the local growing conditions (poor soils, high pest and disease pressure). A better understanding of the genes underlying important traits will make the breeding of new cultivars and hybrids much more efficient. We focus specifically on genetic improvement of sugar yield, biomass composition, disease resistance, and efficient use of water, all of which contribute to achieving high yields of fermentable sugars from juice and biomass under limited inputs.
Biofuels and bulk chemicals need to be produced at a low cost in order to be competitive with existing fuels and chemicals produced from fossil fuels. Cost-competitiveness can be accomplished by maximizing crop yield, reducing inputs, streamlining the bioprocessing scheme, and production of high-value co-products that can offset some of the processing costs. We have developed a process to synthesize nanotubes and nanowires from lignin present in the waste stream of the biorefinery. These lignin nanotubes can be used a delivery vehicles for DNA into human cells in tissue culture, and a number of other applications are under investigation. Research funding is provided by the USDA-BRDI, Southeastern SunGrant Initiative and DOE.
Dr. Vermerris is a member of the University of Florida Genetics Institute, and participates in the Genetics & Genomics graduate program and the Plant Molecular & Cellular Biology Graduate Program. He has adjunct appointments in the department of Materials Science & Engineering at UF and the department of Agricultural & Biological Engineering and the Laboratory of Renewable Resources Engineering at Purdue University. He is the co-author of the textbook ‘Phenolic Compound Biochemistry‘, editor of the book ‘Genetic Improvement of Bioenergy Crops’ and Co-Editor-in-Chief of the journal BioEnergy Research.