Research Challenges
Improve bioenergy crop yields and other important biomass traits.
Use genomics and proteomics approaches to identify key regulators of plant growth and biomass synthesis.
Energy-rich plant oils used to generate biodiesel are restricted to seeds, such as soybeans, which are used for food and feed.
Develop bioenergy crop plants that synthesize and retain up to 20% oil in vegetative tissues such as leaves, stems, and tuber—thereby doubling the energy content of these crops and allowing for the production of biodiesel.
Lignin in plant cell walls inhibits enzymes from reaching cellulose and hemicellulose and breaking them down to their component sugars.
Engineer lignin to contain "zips" that can be chemically cleaved under controlled conditions, thereby releasing the polysaccharides for breakdown into simple sugars that can be fermented.
Along with lignin, other poorly understood cell wall structures inhibit biomass deconstruction.
Use a combination of genetic approaches and powerful genomics tools to discover genes and gene variants that can be bred into bioenergy crops to enhance biomass deconstruction.
The cell wall contains 5-carbon sugars that are poorly fermented by microorganisms.
Use a cutting-edge genomics approach to generate polymers rich in 6-carbon sugars.
HIGHLIGHTS
Using 2D NMR to Understand Plant Cell-Wall Composition and Function. Characterization of the composition and structure of the cell wall’s entire polymer complex is difficult because of the amorphous nature and complexity of the molecules. Solution-state nuclear magnetic resonance (NMR) instruments at the GLBRC provide high-resolution profiling (called “fingerprinting”) of cell-wall composition and structure. These methods have been used to provide deeper insight into processes such as the increase in cellulose deposition in poplar tension woods, fungal degradation mechanisms, and the beneficial changes that can occur in a plant when cell-wall gene expression is increased or decreased. Preliminary trials suggest that multivariate methods applied to the two-dimensional (2D) NMR fingerprint of cell walls will provide a useful tool for relating their profiles to other analytical or process data—presumably, for any process that depends on the composition and structure of the wall. The 2D NMR fingerprint then can be used to inform research on optimal feedstock selection, allow biomass conversion efficiencies to be predicted, and aid in pretreatment and process optimization.
