NOV 12, 2015 07:58 PM PST

Oil Dispersants Hinder Oil-Degrading Bacteria

WRITTEN BY: Kerry Evans
Remember the Deepwater Horizon oil spill?  Researchers at the University of Georgia found that chemical dispersants meant to help oil-munching microbes break down oil may have the opposite effect.

The Deepwater Horizon spill spewed nearly 750 million liters of oil into the Gulf of Mexico, and nearly 7 million liters of chemical dispersants were used to clean it up.  Dispersants contain surfactants such as sodium lauryl sulfate that break up oil into small droplets.  Dispersants decrease the amount of oil that makes it to shorelines and may make oil more readily available to microbes for degradation.  
 
Dispersants are meant to make oil available to microbes.
 
The group collected samples from the Gulf of Mexico and treated them with oil, dispersant, or a combination of the two.  They characterized the abundance of Colwellia and Marinobacter.  Species of Colwellia are capable of degrading both hydrocarbons (oil) and dispersants, while Marinobacter mainly degrade hydrocarbons.  Both thrive in cold, deep waters.

Dispersant and dispersant/oil-treated samples increased the abundance of Colwellia from 1% to 26-43%, while its abundance remained low in samples treated with oil alone. On the other hand, Marinobacter increased in abundance from 2% to 42% in oil-treated samples, but remained low in samples treated with dispersant or dispersant and oil.  These results suggest that dispersants applied during the Deepwater spill may have enriched for dispersant-degrading bacteria instead of stimulating the growth of oil-degrading species.

According to study author Samantha Joye, “the fact that dispersants drove distinct microbial community shifts that impacted oil degradation efficiently came as a big surprise … it is critical to quantify the factors that influence the efficiency of oil biodegradation in the environment, and that includes dispersants”.
 

Sources: PNAS, Science Daily, MicrobeWiki, Wikipedia
About the Author
  • Kerry received a doctorate in microbiology from the University of Arkansas for Medical Sciences.
You May Also Like
OCT 23, 2019
Microbiology
OCT 23, 2019
To Survive Environmental Challenges, Red Algae Grab Bacterial Genes
Cyanidiales are a group of red algae species. Researchers have found that about 10% of them have acquired genes from bacteria....
OCT 23, 2019
Microbiology
OCT 23, 2019
How a Magnetic Bacterium Creates a Compass Needle
There are organisms that can use the magnetic field of the earth to navigate, including animals like honey bees and migratory birds, and some bacteria....
OCT 23, 2019
Cardiology
OCT 23, 2019
Stem Cells Improve Post Infarction Repair
Following a heart attack, tissues within the heart are often damaged. Once damaged, the heart is incapable of regeneration of these tissues. These dead are...
OCT 23, 2019
Microbiology
OCT 23, 2019
Dengue Virus Changes According to the Temperature
Four related types of dengue virus are common in at least 100 countries and threaten around three billion people....
OCT 23, 2019
Cell & Molecular Biology
OCT 23, 2019
Researchers Discover a Cause of Antibiotic Resistance
For years, people have relied on antibiotics to cure bacterial infections, and many of those antibiotics are now becoming less effective....
OCT 23, 2019
Microbiology
OCT 23, 2019
Potential New Antibiotic Discovered in Soil-Dwelling Microbe
Many of our best antibiotics have come from microbes, which have to use them to battle other microorganisms in a struggle for resources....
Loading Comments...