For years, San Diego scientists have been working on making fuel from algae with the long-term goal of replacing fossil fuels with something renewable and carbon-neutral. But so far, it has been a steep challenge to make algae-based fuel cheap enough to compete with the stuff we buy at the pump.
Now, San Diego-based Synthetic Genomics and oil giant Exxon Mobil said they have created a genetically modified strain of algae that takes a significant step closer to making algae biofuel commercially viable.
Inside a darkened lab at the Synthetic Genomics offices in La Jolla, different strains of genetically tweaked algae bubble away in little tanks. All the blinds are drawn — the scientists use artificial lights to simulate a 24-hour day in the California desert.
"We're trying to mimic what the algae would see in an outdoor setting, in a pond," said Imad Ajjawi, one of the scientists working on algae at Synthetic Genomics.
"The lights are actually programmed to mimic the fourth of May in Southern California, out in the Imperial Valley," he said. "Plenty of light. You get your dusk. You get your dawn as well. We're really trying to see what would happen out there in the environment."
Ajjawi is the first author on a study published Monday in the journal Nature Biotechnology. It describes new GMO algae that took years to develop, and Synthetic Genomics said it represents a key milestone in their biofuel program.
The engineered strain is a big step forward, Ajjawi said, because it can produce double the oil of a natural algae strain, but still grows just as well as its leaner cousin in the wild.
"Think about it in terms of an athlete," he said. "Athletes are very high in protein, they're very fit. But they don't contain that much oil — that much lipid. They're not that fat."
Ajjawi and his colleagues wanted algae that were both fat and fit. Not a marathon runner. Not a couch potato. Something more like a sumo wrestler.
So they combed through the algae’s 9,000 genes, narrowing in on about 20 that appeared to regulate fat. They selectively turned off each of those genes using CRISPR, a relatively new and powerful gene-editing tool. When they turned off one particular gene, they saw a dramatic change.
"We realized that it was making a ton of fat," Ajjawi said. "It was actually off the charts. I remember being in the lab, talking to one of the [research assistants] and asking him to show me the data. We were both wondering where the data point was for that specific strain, and it turns out that it was literally off the scale."
The researchers think that if algae can produce more oil without slowing down growth, it could one day compete with fossil fuels.
Synthetic Genomics was co-founded by human genome sequencing pioneer J. Craig Venter. At a conference in San Diego this week, Venter said the stakes for this work are high.
"With the president pushing coal and denying climate change, the urgency is greater than ever," he said. "As much as we can accelerate this, we would like to."
Synthetic Genomics may be aiming to develop an alternative to petroleum. But they are actually working with one of the world's biggest oil companies, Exxon Mobil, to get there. Exxon has funded algae research at Synthetic Genomics, and they have recently put out commercials featuring scientists who work on algae.
But will it be possible for algae to power our daily commutes anytime soon? Scripps Institution of Oceanography researcher Greg Mitchell — associate director of UC San Diego's California Center for Algae Biotechnology — said it is unlikely.
"At some local gas stations, we could be doing it within five years, at small scale," Mitchell said. "But if we're talking about the USA — a couple hundred million people doing it — it's many decades away."
Mitchell said Synthetic Genomics has pulled off a scientific feat with this study. But with gas still so cheap, costs would have to come way down before algae could become a meaningful source of energy.
"The deployment at scale is not there yet," he said. "That's going to take quite a bit more time. And it may not be this organism, but this points the direction of how we could go."
Imad Ajjawi said algae biofuel is still very much in the research stage.
"With disruptive technologies such as this, you really can't set a timeline," Ajjawi said. "You have to be patient. And that's the good part about having Exxon Mobil as a partner. They recognized that and knew that we needed to be patient in order to achieve success."
Ajjawi remembers when he first came to Synthetic Genomics seven years ago. They had a goal: doubling algae's oil production without hindering its growth. Synthetic Genomics' algae biofuel is still a long way from reaching gas tanks. But Ajjawi said this week, his team is celebrating their success at meeting that scientific goal.
