DOE Researchers Report Breakthrough for Cheaper Biofuels

January 4, 2012

Photo of a man with swtichgrass growing in a field.

New molecular breakthroughs could help in designing E. coli that better digest switchgrass and other plants to help make biofuels.
Credit: Todd Johnson

Researchers at DOE's Joint BioEnergy Institute (JBEI) announced on December 22 a major breakthrough in engineering systems of RNA molecules using computer-assisted design. The innovation could lead to important improvements across a range of industries, including the development of less-expensive advanced biofuels. Scientists will use these new "RNA machines" to adjust genetic expression in the cells of microorganisms. This will enable scientists to develop new strains of Escherichia coli (E. coli) that are better able to digest switchgrass biomass and convert released sugars to form gasoline, diesel, and jet fuels. JBEI is led by researchers at DOE's Lawrence Berkeley National Laboratory.

A breakthrough with E. coli could lower the cost of producing advanced biofuels from switchgrass or other non-food biomass plants, with the potential to replace gasoline. While the work at JBEI remains focused on the development of advanced biofuels, JBEI's researchers believe their concepts could help other researchers to develop many other desired products, including biodegradable plastics and therapeutic drugs. For example, some researchers have already started a project to investigate using the "RNA machines" to increase the safety and efficacy of medicine therapies to treat diseases, including diabetes and Parkinson's.

Biological systems are very complex, which makes it difficult to engineer systems of microorganisms that will produce desired products in predictable amounts. JBEI’s work—featured in the December 23 issue of Science magazine—is the first of its kind to set up and adjust an RNA system in a predictable way.

Specifically, researchers focused their design-driven approach on RNA sequences that can fold into complicated three-dimensional shapes called ribozymes and aptazymes. Using JBEI-developed computer-assisted models and simulations, researchers then created complex RNA-based control systems that are able to program a large number of genes. In microorganisms, "commands" sent into the cell will be processed by the RNA-based control systems, enabling them to help develop desired products.

A major goal of synthetic biology is to produce valuable chemical products from simple, inexpensive, and renewable starting materials in a sustainable manner. Computer-assisted models and simulations like the one JBEI developed are essential for doing so. Until now, such tools for biology have been very limited, and JBEI’s breakthrough in applying computer-assisted design marks an important technical and conceptual achievement for this field. JBEI is one of three Bioenergy Research Centers established by the DOE’s Office of Science in 2007. See the DOE press release and the JBEI website.