In the results of a new study, scientists explain how they used DNA to identify microbes present in the Gulf of Mexico following the Deepwater Horizon oil spill -- and the particular microbes responsible for consuming natural gas immediately after the spill.
Water temperature played a key role in the way bacteria reacted to the spill, the researchers found.
Proceedings of the National Academy of Sciences (PNAS) published the results in this week's journal.
David Valentine and Molly Redmond, geochemists at the University of California at Santa Barbara (UCSB) conducted the study. The National Science Foundation (NSF) and the Department of Energy supported it.
The Deepwater Horizon oil spill was unique, according to Valentine and Redmond, because it happened at such great depth and contained so much natural gas -- predominantly methane, ethane and propane.
Those factors influenced the way bacteria responded to the spill.
In earlier studies, Valentine, Redmond and colleagues showed that ethane and propane were the major hydrocarbon compounds consumed in June 2010, two months after the April spill.
By September 2010, the researchers discovered that these gases and all the methane had been consumed.
In May and June of 2010, the scientists found that bacterial communities in the submerged plume were dominated by just a few types -- Oceanospirillales, Colwellia and Cycloclasticus -- and were very different from control samples without large concentrations of oil or gas.
The bacteria were also very different from the microbial communities in surface oil slicks collected at the same time.
"It's much warmer at the surface than in the deep water -- around 80 degrees Fahrenheit versus 40 F, which is pretty close to the temperature in your refrigerator," said Redmond, the PNAS paper's lead author.
"There was very little natural gas in the s
|Contact: Cheryl Dybas|
National Science Foundation