We all know that oil spills are a huge environmental issue, but there are far more spills than the few majors ones we tend to hear about in the news. Where does all that oil go? Mandy Joye from the University of Georgia studies how microbes degrade hydrocarbons and react to oil spills. Comparing naturally occuring hydrocarbon degrading communities to the community present at an oil spill event can shed light on how microbes can clean up oil more efficiently.
Mandy studies a deepwater plume of oil in the Maconda Area. One of the surprising results was that the community became dominated by Gammaproteobacteria and stayed that way for several months. The specific taxa that were abundant during the spill were not major community members in the natural hydrocarbon community or before the spill, and the community never returned back to its previous composition. This points to previously unknown hydrocarbon degrading capabilities in the microbial communities.
Chemical dispersants are one method to clean oil spills. In lab experiments, Marinobacter (according to Mandy, the superhero of the community and not a picky eater!) is present in treatments of deep water with oil but not in treatments with oil and dispersant. Hydrocarbon degradation rates also decreased when dispersant was added. Instead, strains of a different microbe named Colwellia become abundant, and the community did not recover hydrocarbon degrading abilities.
So if chemical dispersants may actually prevent hydrocarbon degradation, what should we do instead? Mandy found that supplementing nutrients such as nitrate boosts the levels of hydrocarbon-munching Gammaproteobacteria. Learning more about interactions with these communities may provide even more insight on how we can harness the power of microbes to clean oil spills quickly and efficiently.