Start-up plans to spray the bacteria over oil-covered waters
Discovery News 6/14/10
Two weeks ago, Ben Lyons, a research scientist and engineer at the small biotech firm Evolugate, hopped in his car and drove from his lab in Gainesville, Fla., to New Orleans. There he talked his way onto a 9-meter catamaran that was heading out on a research trip into the Gulf of Mexico to investigate the massive oil spill from a gushing BP well.
About 30 kilometers south of the Mississippi River Delta, Lyons scooped up a dozen liters of water and oil. That mixture now fills his company’s bioreactor, a 4-meter-long translucent tube with a laser that shoots beams through the liquid. Inside, populations of 18 types of oil-eating microorganisms are feasting on BP’s oil.
Lyons and his colleagues hope that during the next 6 months, their bioreactor will help to rapidly evolve a population of superefficient oil-eating bacteria ideally suited to the conditions of the Gulf of Mexico. Later this year, the company plans to spray the bacteria over the Gulf’s oil-covered waters. But Evolugate is facing long odds. In peer-reviewed scientific studies, seeding oil spills with microbes has never helped the cleanup process, and microbiologists who worked on the Exxon Valdez spill off the coast of Alaska doubt that the outcome will be different this time.
”There was an awful lot of hype in the 1970s and 1980s about adding bacteria, and it didn’t really pan out,” says Robert Howarth, a professor of ecology and environmental biology at Cornell University who worked on the Exxon Valdez cleanup effort.
The Exxon Valdez spill was the site of the world’s largest experiment in a technique called bioremediation, which aimed to add bacteria and nutrients to the oil-filled water, says Ronald Atlas, a biology professor at the University of Louisville, but the efforts failed. ”The bacteria are already out there,” says Kenneth Lee, a researcher who founded the Centre for Offshore Oil, Gas and Energy Research at the Bedford Institute of Oceanography, in Dartmouth, Nova Scotia. ”If it wasn’t for bacteria, we’d be knee-deep in oil.” That is, adding foreign microorganisms did not accelerate the naturally occurring process by which native populations of bacteria degrade oil in water.
The problem, Lee and Atlas say, is that besides oil, the bacteria need other nutrients in greater abundance for their populations to grow. ”What is useful is the addition of a fertilizer -- nitrogen or phosphorus,” Atlas says. And not just anywhere: Adding fertilizers, if it works at all, would work best in coastal areas rather than in the open ocean, where Deepwater Horizon is gushing and the nutrients can easily disperse. For fertilization to work in open waters, engineers would likely need to come up with a way to force the nutrients to bind to the oil, he says.
But even if adding fertilizers boost bacterial growth in coastal waters, it has a dark side, says Cornell’s Howarth. ”About two-thirds of coastal water and bays [in the United States] are severely degraded by nitrogen and phosphorus pollution,” he says. Leaving the environment’s native bacteria to do their own cleanup might be just as good, he adds.
Thomas Lyons (no relation to Ben Lyons), Evolugate’s principal research scientist, maintains that his company has a new approach. ”We believe the reason it hasn’t worked in the past is because the microbes haven’t been adapted,” he says. ”Our methodology is, you’ve got to get oil from the actual site where you’re going to be putting the microbes.” As the experiments go forward, Thomas Lyons says that his staff will collect more samples from the waters and marshes along the Gulf Coast and attempt to evolve ”designer communities” for each sample.
To make sure the conditions in the bioreactor continue to mimic the environment in the Gulf, Ben Lyons periodically checks the temperature inside the bioreactor remotely from his iPhone. By tracking how a laser beam diffuses through the microbe populations in the bioreactor, he can observe how fast the organisms are multiplying.
If they get lucky, the scientists at Evolugate will accelerate the evolution of a population of oil-devouring microbes perfectly tuned to life in the Gulf. But so far, the scientific record is not in their favor.
