Meet the Microbes Eating the Gulf Oil Spill [Slide Show]
These microscopic life forms are blooming as a result of the oil spilled into the Gulf of Mexico from the Macondo 252 deep-sea well
![Meet the Microbes Eating the Gulf Oil Spill [Slide Show]](https://static.scientificamerican.com/sciam/cache/file/C8A21F0D-BE02-4EB5-99948D9889731E72.jpg?w=590&h=393)
Meet the Microbes Eating the Gulf Oil Spill [Slide Show]
- THALASSOLITUUS OLEIVORANS: Much like A. borkumensis, T. oleivorans makes its living by turning the alkanes in oil into microbial cells, CO2 and water—and can be found from the Black Sea to the Gulf of Mexico, as can other members of the Thalassolituus genus. Unfortunately, such similarly-minded bacterium don't cooperate; some experiments show that adding T. oleivorans reduces the activity of A. borkumensis and other oil-eating microbes as the tiny bacteria vie for oil-ingesting supremacy. Humans aren't the only species waging chemical warfare in the Gulf. Courtesy of Michail M. Yakimov / International Journal of Systematic and Evolutionary Microbiology
- NEPTUNOMONAS (GENUS): Some members of this genus attack the carcinogenic constituents found in most oil deposits—the aforementioned polycyclic aromatic hydrocarbons—and can be found throughout the planet's oceans. Members of the genus play a role not only in cleaning up oil spills—but also the fatty acid residue of whale carcasses, like Neptunomonas japonica pictured here. Other microbial genuses that contribute to such toxic tidying are Pseudomonas and Vibrio, although they may not be as abundant as Neptunomonas or Cycloclasticus. Courtesy of Masayuki Miyazaki / International Journal of Systematic and Evolutionary Microbiology
- OLEISPIRA (GENUS): Another alkane eater (like A. borkumensis), various Oleispira turn oil into more and more Oleispira cells, along with carbon dioxide and water. One unintended side effect can be local "dead zones," as the industrious microbial consortia, like the one pictured here, consume much of the dissolved oxygen in the seawater as they feast on the oil. Another extremophile species in this genus has been found in Antarctic waters (Oleispira antarctica) as well as the subtropical waters into which the Macondo well has been spilling. Courtesy of Bangor University
- OCEANOSPIRILLALES (ORDER): This order of microbes—part of the Proteobacteria phylum, named after the shape-shifting Greek god Proteus—assume a number of forms and roles in eliminating an oil spill. The most famous oil-eating member of the order is the aforementioned A. borkumensis, but other members can play a role in eliminating petroleum as well. Pictured here is the salt-loving Halomonas elongata, which grows best in extreme environments but does not eat oil. Courtesy of Expedition Zone
- COLWELLIA (GENUS): This clan of oil-eating microbes can be found from cold Arctic and Antarctic waters to the balmy seas of the Gulf of Mexico. It also has the ability to thrive in a variety of habitats, from marine sediments to Arctic sea ice—making it one of the more adaptable spill fighters. Given that oil in sediments—or cold waters—is much harder to break down, scientists are in hot pursuit of this wide-ranging extremophiles' spill-fighting traits. Richard A. Finkelstein / NCBI
- DREDGING FOR CYCLOCLASTICUS: Some of the most dangerous constituents of an oil spill are polycyclic aromatic hydrocarbons—volatile molecules that can be highly toxic. Fortunately, at least 23 strains of the bacterial genus Cycloclasticus native to the Gulf of Mexico can degrade such nasty oil constituents by tapping them for energy. Even better, some members of the rod-shaped group can eat other aromatic hydrocarbons that are even more toxic, such as toluene. And they have tiny flagella to help them move from source to source, cleaning up toxics as they go. As a result, scientists are busily decoding Cycloclasticus pugettii, a strain found in the waters of the Puget Sound and being dredged for here, in the hopes of improving its toxic avenger abilities. Courtesy of Washington State Department of Ecology
- ALCANIVORAX BORKUMENSIS: A rod-shaped bacterium, A. borkumensis has played a role in oil spill cleanups from Alaska (Exxon Valdez) to the Mediterranean waters near Spain (Prestige). Although it persists in low numbers at all times, the bacterium blooms after an oil spill—and has the ability to both break down the alkanes that make up part of the oil as well as spread a biodispersant that helps other microbes feast on other constituents of the spill. As a result, scientists have been attempting to "soup up" this oil-eater via genetic manipulation in order to make a spill-fighting supermicrobe. So far, they have not improved on evolution's design. Courtesy of Heimholtz Center for Infection Research (HZI)
