The oil well of tomorrow may be in a California lab full of genetically modified, diesel-spewing bacteria.
That path began unexpectedly at Codon Devices, Harvard geneticist George Church's rapid-DNA-synthesis company. Church and his lab staff had regular brainstorming sessions in which they liked to muse on out-of-the-box applications for the technology they'd developed, which allowed them to redesign the genomes of existing organisms with a few mouse clicks. One day, someone suggested engineering a bacterium that could make fuel, since the lab had just been awarded a Department of Energy grant. "We're dependent on petroleum, so we don't need some alternative to petroleum. We need a way to make petroleum itself," del Cardayré says. "Biology can do it. Over the course of billions of years, cells have figured out that hydrocarbons are a good way to store energy."
Accordingly, LS9 is staking its prospects not on inventing an entirely new biological pathway, but on exploiting an existing one. Bacteria naturally turn the sugars they consume into fatty acids, which are later converted to lipids for storage. By a stroke of genetic serendipity, fatty acids are only a few molecular linkages removed from diesel fuel, so it has been fairly simple for LS9 scientists to tweak existing bacteria--including familiar varieties such as E. coli--to yield new, diesel-producing strains. "We divert those fatty acid pathways," del Cardayré says. "It's like a detour."
The strategy has already met with small-scale success; an assortment of odd-shaped beakers lines the San Carlos lab's shelves, each holding a few teaspoons of amber-colored diesel. Walsh estimates large quantities of the finished fuel will be market-ready in three to five years. The company is also perfecting a bacterium that produces crude oil, which could be sent to refineries and turned into any imaginable petroleum product, from gasoline to Vaseline
Still, a host of practical problems must be solved before this industry can take off, and some may prove to be deal breakers. For one thing, public skepticism about all things genetically modified, from food to pet goldfish, may make it difficult for these companies to gain regulatory approval for their products. In a 2006 Pew Initiative study, almost a third of respondents said they viewed genetically modified products as unsafe. "The cry right now is for anything to replace petroleum, but $95 crude is masking a lot of the issues," says Martin Tobias, a biodiesel expert and venture capitalist at Ignition Partners. "It's going to be 10 times harder to get something like this available and accepted than if you were using a naturally occurring organism. Think how difficult it is to get genetically engineered drugs approved."
Then there's the multimillion-dollar question of how to translate a beaker of success to global scale. No one has ever made genetically engineered fuel in industrial quantities, so no one knows what's going to happen when companies try to grow their bacteria in vats the size of trailers. Startups producing biodiesel from algae--which are closely related to bacteria--have encountered difficulties when trying to scale up; in large numbers, the organisms sometimes crowd one another out and emit toxic waste that halts the production process. "Even if you can do this in a test tube, getting the same kind of quality on a large scale could be an issue," says Tom Todaro, CEO of Targeted Growth, a company that's aiming to increase the efficiency of biodiesel production. "People fail to understand how big the oil and gas industry is--just how much fuel you have to be able to produce in a day to compete."
Church admits the challenges are daunting; he isn't picturing bacteria-fuel pumps at every Mobil station just yet. "We know we'll be competing with hydrogen, ethanol, and electric cars," he says. But in unguarded moments, he dares to dream: "If this works out, much of the current motivation for switching away from hydrocarbons might vanish." Why seek an alternative to petroleum, he figures, when a microscopic army of trillions can churn it out for you 24-7?
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