Pouring sugar into your car’s fuel tank is a bad idea. At least for the time being. But the field of synthetic biology could one day be able to design and produce organisms that convert starches and sugars into hydrogen – creating fuel within your car. Last week, an announcement from Craig Venter may have moved the world one step closer to a sweet ride.
At a press conference on Thursday, Venter – of human genome sequencing fame – announced that his research team had created the first self-replicating, synthetic bacterial cell. In essence, they stitched together a chain of DNA based on one species of bacterium, inserted it into an empty cell of another species of bacterium and watched as their synthetic creation took over and began replicating.
For several years now, scientists have been able to add or delete specific genes and rewire cells to manufacture selected by-products. But Venter’s announcement marks the first time scientists have created a genome from scratch that can reproduce itself.
The discovery could herald grand possibilities for harnessing the power of cells. “This is a huge increase in our toolbox for approaching research,” Venter told Need to Know. “We need new science, new tools to be able to produce food, energy and medicine without harming the environment.”
While practical applications may be at least a decade away, Venter and his collaborators have been thinking about how biology might enter the energy landscape for some time.
“We started our thinking of this whole process 15 years ago,” said Venter. “After sequencing the human genome and looking around at how to use the technology, we saw the biggest problem on the planet was the environment.”
Even before oil prices spiked, Venter says he saw the promise synthetic microorganisms might hold for the transportation sector. The Department of Energy did as well and was an early funder of Venter’s research. Numbers collected by David Rejeski, the director of the Science and Technology Innovation Program at the Woodrow Wilson International Center for Scholars, illustrate the DoE’s interest in developing new biofuels. Rejeski’s team puts a conservative estimate of DoE spending on synthetic biology research at $115 million a year for fiscal years 2008-2010. (Rejeski provided these figures to Need to Know before their publication.)
Plant-based biofuels have great potential as a carbon-neutral source of energy. In theory, the carbon released during their combustion would be the same as that originally captured during photosynthesis.
There are several ways these genetically engineered biofuels might work. One is the development of organisms that convert sugars into hydrogen – the sugar in your tank model. That method, though, has the same problem that critics of available biofuels, like ethanol, cite – there remains a need for water-intensive food crops that can cause deforestation and pricing instabilities.
Venter himself favors another approach. Last year, his for-profit company, Synthetic Genomics Inc. (SGI) and ExxonMobil launched a $600 million partnership to develop a biofuel from algae. The idea is to alter the algae’s genetic structure so that they produce fossil-fuel-like hydrocarbons as a product of photosynthesis.
Other big energy companies are interested, as well. BP (also an early funder of SGI) has its own $10 million research deal with a company called Martek Biosciences and Royal Dutch Shell has been part of a joint venture to develop algal biofuels since 2007.
The algal method has a lot going for it. Algae are fast-growing. They don’t need fresh water. And the process provides a pool of continuously producing organisms (rather than a product to be harvested).
But, what it does require are large surface areas for production. Light cannot penetrate far into algal ponds and there would have to be a significant amount of acreage devoted to cultivation to produce fuel on a substantial scale. Venter claims that this “biomanufacturing” needs considerably less land than other plant-derived fuels, but admits that producing enough for the consumer market will be a challenge.
Scalability is one of the main problems synthetic biology faces as it tries to tackle the world’s energy problems. Addressing that dilemma is where ExxonMobil enters the scene. Cynthia Bergman, a spokesperson for the company says that while Venter’s company brings their knowledge in genomics, biology and biochemistry, Exxon’s expertise “comes in the manufacture of transportation fuels and how you go from the lab to scaling up to commercial production and application.”
If they solve scalability, another not-inconsiderable hurdle for synthetic biology to overcome is the potential risk in unleashing engineered organisms on a nonlaboratory environment. While microbes have already been created that can help clean up oil spills, regulators are wary of releasing their microbial counterparts that could remediate pesticides or radioactive compounds. Under current models, it’s difficult to predict what sort of environmental impact they may have.
Researchers can engineer genetic “fail-safes” into synthetic microbes that have them die off within a limited number of generations or after their targeted food source is gone. But imagine a scenario where a C02-chomping bacterium goes into overdrive or a DDT-munching cell mutates and decides it also likes the taste of other, safer pesticides. The risks could be considerable and hard to assess in advance.
Synthetic biology is a field that holds much promise, but will be closely watched by government agencies and environmental advocates. On the same day as Venter’s recent public announcement, President Obama sent a letter to the chair of the Presidential Commission for the Study of Bioethical Issues requesting a review of the implications of this “scientific milestone.” He asked that the commission present him with a report in six months that considers both potential benefits and risks.
Hear Venter’s TED talk on his historic annoucement: