Rebooting Biofuels

“Something I’m really excited about are the synthetic biology projects they’re working on to create new kinds of fuels so we can reduce our dependence on oil and protect our environment.” – Arnold Schwarzenegger, Governor of California. At the US Department of Energy’s (DOE), Patrinos had overseen both the Human Genome Project and more recently the Genomes to Life (GTL) programme – which supports research to focus synthetic biology on the production of biofuels such as ethanol and hydrogen. The current buzz phrase for ethanol is “energy independence.” Environmental groups such as Natural Resources Defense Council (NRDC) are also championing the development of certain types of ethanol that could reduce global emissions of carbon dioxide and prove to be climate-friendly fuel. The biofuel buzz is about to become a boom because the US government mandates that at least 30 percent of transport uel be derived from biofuels (mostly ethanol) by 2030 –requiring roughly 60 billion gallons of ethanol to be produced per year. Brazil is using sugarcane and corn in US for ethanol production but US corn production is energy intensive, requiring massive inputs of fossil fuels for fertilisers, pesticides, tractors, post-harvest processing and transport. The synthetic biology approach is to custom design a microorganism that can utilize wide range of cellulosic biomass to produce ethanol with high yield. A team from the University of Stellenbosch (South Africa), collaborating with engineering professor Lee Lynd at Dartmouth University (USA), has engineered a yeast that can survive on cellulose alone, breaking down the plant’s cell walls and fermenting the derived sugars into ethanol. Meanwhile, Lynd’s group at Dartmouth is working with a modified bacterium that thrives in high-temperature environments and produces only ethanol in the process of fermentation. Lynd hopes to commercialise his technology at a start-up company called Mascoma in Cambridge, Massachusetts (USA). Chairing Mascoma’s board of directors is venture capitalist and ethanol evangelist, Vinod Khosla, also funds another synthetic biology energy company known as LS9, based in the San Francisco Bay area (CA, USA). Similarly, at Purdue University’s Energy Center, Senior Research Scientist, Dr. Nancy Ho, has developed a modified yeast that can produce 40 percent more ethanol from biomass than naturally occurring yeast, and the Nobel Prize-winning head of the prestigious Lawrence Berkeley Lab, Dr. Steven Chu, who grabbed headlines last year when he suggested that synthetic biology could be used to rewire the genetic networks in a cellulose-crunching bug found in the gut of termites. As a first step, the Berkeley Lab is sequencing microorganisms living in the termite’s gut, to identify genes responsible for degrading cellulose.