Because bacterial remediation methods have not succeeded, cleaning up oil spills still depends mainly on the laborious process of physically removing the oil using booms and introducing chemical dispersants to break up what remains. But such methods are less than ideal. Recovering oil physically is expensive, and the chemically dispersed oil that remains in the sea still poses a threat to the environment even if it is no longer visible on the surface.
But decoding the genome of organisms like A. borkumensis is going to make a difference, says Jan van Beilen, a microbiologist who studies the molecular genetics of oil-eating organisms at the Institute of Molecular Systems Biology in Zurich, Switzerland. The genomic information has revealed molecular transport mechanisms that enable the organism to scavenge nutrients from its environment. This should, in turn, help identify which forms of phosphorus and nitrogen would create the best conditions for the bacteria.
The research could also identify the plethora of genes that produce the oxidative enzymes the bacteria use to degrade the oil, which should make it easier to search for other organisms with similar capabilities.
And such organisms will be needed. A. borkumensis can only metabolize compounds of low molecular weight, and these make up only about 70 percent of crude oil. So the next step is to look for organisms that are specialized to consume the remaining high-molecular-weight compounds, says van Beilen.
Sequencing A. borkumensis is only the first step, says Martins dos Santos. But, he says, research is under way in the United States, Australia, and Japan to sequence other oil-eating bacteria.In the meantime, Martins dos Santos and colleagues have already begun applying the knowledge gleaned from A. borkumensis’s genome. Working with the Alfred Wegener Institute in Bremerhaven, Germany, they are running pilot tests in tanks in the North Sea to see if they can improve the bacteria’s appetite. “We add these bacteria, add nutrients, and try to see how they react,” he says.