Featured Research

from universities, journals, and other organizations

Marine Methane Consumed By Consortia Of Bacteria

Date:
July 20, 2001
Source:
Penn State
Summary:
Methane consuming archaeobacteria and sulfate-reducing bacteria, acting together, are responsible for consuming most of the methane in the world's oceans, according to a team of microbiologists and geoscientists.

University Park, Pa. – Methane consuming archaeobacteria and sulfate-reducing bacteria, acting together, are responsible for consuming most of the methane in the world's oceans, according to a team of microbiologists and geoscientists.

"Past research had shown that there is a consortia of these two very different single-celled organisms, and indirect tests indicated they might be the source of methane consumption," said Dr. Christopher H. House, assistant professor of geosciences at Penn State. "We decided to directly test if these organisms are responsible."

The research team explains their approach in today's (July 20) issue of the journal Science. Research team members Victoria J. Orphan, graduate student, and Dr. Edward F. Delong, chair of the science department at Monterey Bay Aquarium Research Institute, were responsible for identifying the organisms in the consortia. The sulfate-reducing bacteria, Desulfosarcina, and the methane-consuming archaeobacteria, Methanosarcinales, were tagged with flouresent dyes that attach only to individually specific genetic material. In this way, one dye attached to the Desulfosarcina and another, of a different color, attached to the Methanosarcinales. Investigation under flourescent light showed the sulfate-eaters surrounding the methane eaters in an aggregated clump about the diameter of the width of a human hair.

"To determine that these aggregates were responsible for the methane consumption, we had to test the organisms to see which carbon isotopes were incorporated into the cells," says House at Penn State.

House and Orphan, working with Dr. Kevin D. McKeegan, professor of Earth and space sciences, University of California, Los Angeles, employed an ion probe that uses cesium ions focused to a very small spot to slowly erode the cells for study. The probe allowed samples of the carbon from the consortia to be tested, beginning with the outer cells and then tunnelling toward the middle of the clump.

Carbon isotopes were the component of interest because the percentages of different carbon isotopes found in living tissue relates directly to what the organism eats. If a bacteria eats food depleted in carbon 13, then the bacteria will be depleted in carbon 13. Methane is very depleted in carbon 13 so a carbon signature low in carbon 13 would indicate the bacteria ate methane.

"The carbon isotope profile that we obtained with the ion probe shows that the sulfate eating bacteria near the outside of the clump are slightly depleted in carbon 13, but that the archeobacteria in the center of the clump are very depleted in carbon 13. "The isotopic signature seen in the consortia of microorganisms indicates that the archaeobacteria in the center are consuming methane," says House.

To confirm their findings, Kai-Uwe Hinrichs, assistant scientist at Woods Hole Oceanographic Institute, tested the lipids in the bacteria and obtained a similar carbon isotope signature. The researchers also tested other microorganisms from the same environment to determine their carbon isotope signitures and found that they were all in the normal carbon 13 range.

Marine methane is produced by archaeobacteria in the abscence of oxygen, usually in the marine sediments. About 80 percent of this methane is consumed in the ocean and never enters the atmosphere.

"If all the methane entered the atmosphere, the Earth would be much hotter because methane is a greenhouse gas," says House. "We knew that did not happen, but we did not know who was consuming the methane. Now we do."

The Penn State researcher notes that this is the first time that phylogenetic staining and isotope analysis have been coupled to show that a specific organism has a specific carbon signature.


Story Source:

The above story is based on materials provided by Penn State. Note: Materials may be edited for content and length.


Cite This Page:

Penn State. "Marine Methane Consumed By Consortia Of Bacteria." ScienceDaily. ScienceDaily, 20 July 2001. <www.sciencedaily.com/releases/2001/07/010720093438.htm>.
Penn State. (2001, July 20). Marine Methane Consumed By Consortia Of Bacteria. ScienceDaily. Retrieved August 28, 2014 from www.sciencedaily.com/releases/2001/07/010720093438.htm
Penn State. "Marine Methane Consumed By Consortia Of Bacteria." ScienceDaily. www.sciencedaily.com/releases/2001/07/010720093438.htm (accessed August 28, 2014).

Share This




More Matter & Energy News

Thursday, August 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Australian Airlines Relax Phone Ban Too

Australian Airlines Relax Phone Ban Too

Reuters - Business Video Online (Aug. 26, 2014) Qantas and Virgin say passengers can use their smartphones and tablets throughout flights after a regulator relaxed a ban on electronic devices during take-off and landing. As Hayley Platt reports the move comes as the two domestic rivals are expected to post annual net losses later this week. Video provided by Reuters
Powered by NewsLook.com
Hurricane Marie Brings Big Waves to California Coast

Hurricane Marie Brings Big Waves to California Coast

Reuters - US Online Video (Aug. 26, 2014) Huge waves generated by Hurricane Marie hit the Southern California coast. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Chinese Researchers Might Be Creating Supersonic Submarine

Chinese Researchers Might Be Creating Supersonic Submarine

Newsy (Aug. 26, 2014) Chinese researchers have expanded on Cold War-era tech and are closer to building a submarine that could reach the speed of sound. Video provided by Newsy
Powered by NewsLook.com
Breakingviews: India Coal Strained by Supreme Court Ruling

Breakingviews: India Coal Strained by Supreme Court Ruling

Reuters - Business Video Online (Aug. 26, 2014) An acute coal shortage is likely to be aggravated as India's supreme court declared government coal allocations illegal, says Breakingviews' Peter Thal Larsen. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins