VATIS UPDATE Article

Scientists at Heriot-Watt University (Heriot-Watt), the United Kingdom, have cracked the genetic code of the marine bacteria which helped ‘eat’ the oil spilled in the Deepwater Horizon disaster, information which could aid clean-up efforts for any future major spill. Dr. Tony Gutierrez, at Heriot-Watt, was in the US at the time of the disaster and was able to perform experiments with samples from oil-contaminated waters of the Gulf of Mexico shortly after the spill occurred, samples that contained key species of bacteria that fed on the oil.

Experiments with the samples revealed that certain bacteria had thrived on the oil that gushed into the Gulf, devouring the oil as a preferred food source. Dr. Gutierrez and his colleagues from the University of Texas, the United States, and University of North Carolina, the United States, reveal the genetic pathways these bacteria use to consume the oil, what conditions they thrive in, what oil hydrocarbons they can eat, and how they work in concert during an oil spill. “Oil is a very complex fluid that contains thousands of different types of hydrocarbon chemicals, many of which are toxic and difficult to break down. But some of these bacteria can,” said Dr. Gutierrez.

The findings also revealed an ability of these bacteria to move towards oil droplets and to use scarce nutrients, suggesting that these microbes are like sentinels in the ocean that are well-adapted to respond quickly to the influx of oil in the event of a spill. The team also identified the bacteria that work best at different depths. Oceanospirillales, for example, degraded alkanes in the deepwater oil plume, whereas Rhodospiralles and Cycloclasticus were responsible for degrading polycyclic aromatic hydrocarbons (PAHs), which are recognised as some of the most toxic chemicals in oil.