Hanover, New Hampshire – Researchers at Dartmouth University in New Hampshire have genetically engineered a thermophilic bacterium that grows at high temperatures and produces ethanol as the only product of its fermentation. The researchers have published their study in the journal Proceedings of the National Academy of Science.
“Our discovery is one potential avenue for research to facilitate turning inedible cellulosic biomass, including wood, grass and various waste materials, into ethanol,” said Professor Lee Lynd. “In the near term, the thermophilic bacterium we have developed is advantageous, because costly cellulase enzymes typically used for ethanol production can be augmented with the less expensive, genetically engineered new organism.”
Lynd said that the discovery is only the first step for future development of ethanol-producing microbes that can make ethanol from cellulosic biomass without adding enzymes. The raw material, cellulosic biomass, is available on a large scale, does not include food crops, and is cost-competitive with petroleum on both an energy and a mass basis. The study said that the technology to convert cellulosic biomass to ethanol is steadily improving, and has the potential to be cost-effective with gasoline production; environmental benefits include a sustainable carbon cycle with near-zero net greenhouse gas emissions, because the carbon dioxide captured growing the biomass roughly equals what is emitted when running an engine.