How beach microbes responded to the Deepwater Horizon oil spill

May 20, 2014 by Dan Krotz
Reginal Lamendella collecting samples. She was part of a team of Berkeley Lab scientists that analyzed how beach microbes reacted to the oil that washed ashore.

(Phys.org) —In June, 2010, two months after the Deepwater Horizon oil spill, Regina Lamendella collected samples along a hard-hit beach near Grand Isle, Louisiana. She was part of a team of Berkeley Lab researchers that wanted to know how the microbes along the shoreline were responding to the spill.

Some microorganisms love to consume hydrocarbons, and they're known to thrive in the Gulf of Mexico. But were -hungry microbes also active on the beach?

The latest results are now in. As reported in a recent issue of the journal Frontiers in Microbiology, the scientists found a bloom in the abundance and diversity of microorganisms that have the ability to degrade oil.

Their research sheds light on a lesser-studied aspect of the environmental disaster. While numerous studies have explored what happened to the oil in the Gulf of Mexico, less is known about the fate of the oil that washed ashore early in the spill history.

Their work could also help scientists develop a "microbial fingerprint" of for similar coastal ecosystems.

"We found that when the oil reached shore, it caused shifts in the microbial communities toward a hydrocarbon-degrading consortium," says Lamendella, who conducted much of the work while a post-doctoral researcher in Berkeley Lab's Earth Sciences Division. She is now a guest scientist at Berkeley Lab and an assistant professor of biology at Pennsylvania's Juniata College.

Here’s what a microbial response to oil looks like. The inner circle depicts the metatranscriptome of a sample collected on June 3, 2010. The outer circles depict the extent to which these expressed genes map to a microbe called Marinobacter aquaeolei strain VT8, one of the more prevalent species in the samples.

Janet Jansson, a senior staff scientist in the Earth Sciences Division, led the research and is the corresponding author of the study.

The scientists collected more than 150 oil-contaminated and uncontaminated samples in June 2010, while the oil accumulated on the beach. They then brought the samples to Berkeley Lab for analysis.

To find out what kinds of microbes were flourishing along the beach, they sequenced the 16S ribosomal RNA genes in the samples. These protein-making genes are found in all microbes, and in general each species has a unique variation. The scientists found that oil-contaminated samples had an abundance of 16S ribosomal RNA genes that corresponded to microbial families with members known to degrade hydrocarbons.

They also mapped the metatranscriptome present in the contaminated samples. A metatranscriptome is the "readout" of all of the genes active in a community at a given time. The data revealed the expression of several genes that degrade chemicals found in hydrocarbons. These genes are closely related to from oil-degrading species such as Alteromonadales, Rhodobacterales, and Pseudomonales.

They also isolated one of the most prevalent bacteria in the samples, and incubated it in the presence of oil obtained from the ruptured well. The experiments found that the bacterium, called Marinobacter, has the potential to transform hydrocarbons.

"We found a succession in the composition of at the beach," says Jansson. "This research may assist in the understanding of microbial proxies for oil contamination in similar coastal areas."

Explore further: US proposes stricter ozone limits

More information: Paper: journal.frontiersin.org/Journa… .2014.00130/abstract

add to favorites email to friend print save as pdf

Related Stories

Oil-eating microbe communities a mile deep in the Gulf

Jul 09, 2013

The Deepwater Horizon explosion on April 20, 2010, caused the largest marine oil spill in history, with several million barrels of crude oil released into the Gulf of Mexico over the course of three months. ...

Recommended for you

India court slams Delhi's worsening air pollution

4 hours ago

India's environment court has slammed the government over the capital's horrendous air pollution, which it said was "getting worse" every day, and ordered a string of measures to bring it down.

US proposes stricter ozone limits

14 hours ago

The US Environmental Protection Agency announced plans Wednesday to strengthen emission regulations for ozone, a smog-causing pollutant blamed for respiratory ailments affecting millions of Americans.

Deforestation drops 18 percent in Brazil's Amazon

17 hours ago

Deforestation in the Amazon rain forest dropped 18 percent over the past 12 months, falling to the second-lowest level in a quarter century, Brazil's environment minister said Wednesday.

The unbelievable underworld and its impact on us all

19 hours ago

A new study has pulled together research into the most diverse place on earth to demonstrate how the organisms below-ground could hold the key to understanding how the worlds ecosystems function and how they ...

Toolkit for ocean health

21 hours ago

The ocean is undergoing global changes at a remarkable pace and we must change with it to attain our best possible future ocean, warns the head of The University of Western Australia's Oceans Institute.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.