Switchgrass, Dubya’s favorite biofuel feedstock, is back in the news. Scientists at the U.S. Department of Energy’s Joint BioEnergy Institute have engineered E. coli — the same bug that is spoiling the lives of raw cookie dough eaters everywhere — to transform switchgrass into gasoline, diesel, and jet fuel.
The secret sauce of their solution is the malleability of E. coli genetics, which allowed researchers to add three new metabolic pathways to the bug. The engineered bugs can break down tough cellulose fibers and ferment the resulting sugars into fuels. Without the bacteria, this used to be an energy- and resource-intensive two-step operation.
"We already have hydrocarbon fuel production pathways that give far better yields than what we obtained with this demonstration,” says Gregory Bokinsky, a post-doctoral researcher who worked on the project. “And these other pathways are very likely to be compatible with the biomass-consumption pathways we’ve engineered into our E. coli.”
None of this means this bacteria will make biofuels affordable with respect to today's gasoline prices. But who knows — give peak oil another 20 or 30 years and we could be scrambling for any source of liquid fuel we can get our grubby, emaciated hands on.
