Bacteria, specifically e. Coli, could one day create biofuels to replace gasoline for your car. Researchers have shown that e-Coli bacteria, similar to those that live in your intestines, can also create precursor materials needed for the creation of efficent, high-octane biofuels.Scientists from the Wyss Institute for Biologically Inspired Engineering at Harvard University and the Department of Systems Biology at Harvard Medical School conducted the study of the bacteria.
Ethanol, the most common gasoline replacement, does not pack as much power as gasoline, and can corrode pipes and storage equipment, while gasoline is both a fossil fuel and a contributor to greenhouse gases. Therefore, the demand is great for a biologically-based gasoline alternative that could run current vehicles and stay in usable form under a variety of conditions. Such a biofuel has just been produced by e- Coli bacteria under the influence of enzymes.
"The big contribution is that we were able to program cells to make specific fuel precursors," Pamela Silver, of the Wyss Institute and Harvard Medical School, said.
To accomplish this, silver and her team used e Coli bacteria to manufacture medium-chain-link fatty acids. These are chains of between four and 12 carbon atoms, along with hydrogen, which can converted into biofuels. This range was chosen since smaller chains do not contain enough energy, and longer molecules of this type are waxy. Two graduate students at Harvard Medical School, Joe Torella and Tyler Ford, adapted e. Coli bacteria to manufacture a fatty acid containing eight carbon atoms, called octanoate, which is convertible to octane.
The pair used an enzyme to successfully encourage the production of the needed fatty acid, but that approach was too expensive for commercial production, so they chose another, less expensive, genetically-altered enzyme to stimulate the process. The next step is to create alcohols with the bacterial process.
Silver and her team believe that their research could benefit not just green fuel, but also be applied to the creation of bioplastics, detergents, herbicides and pharmaceuticals.
"Sustainability is one of the biggest problems we face today, and developing potent biofuels to replace gasoline is a major challenge in the field. Using ingenious synthetic-biology strategies to engineer microbes so that they can produce octane, Pam's team has taken a giant step toward meeting this challenge," Don Ingber, founding director of the Wyss Institute, said.
This new research into the production of biofuels from bacteria was published in the June 24 online edition of the Proceedings of the National Academy of Sciences.
