Subscribe free to our newsletters via your
. Earth Science News .

Probing the Depths of the Methane World
by Johnny Bontemps for Astrobiology Magazine
Moffett Field CA (SPX) May 01, 2014

This is Dr. Jennifer Glass, assistant professor, School of Earth and Atmospheric Sciences at Georgia Tech. Image courtesy Rob Felt.

In 2011, Jennifer Glass joined a scientific cruise to study a methane seep off of Oregon's coast. In these cold, dark depths, microbes buried in the sediment feast on methane that seeps through the seafloor.

A product of their metabolism, bicarbonate, reacts with calcium in seawater to form tall rocky deposits. The chemical energy these organisms extract from methane supports a vibrant underworld - an eclectic blanket of microbial mats, clam fields and tube worms.

"It's such a beautiful landscape," says Glass, an alumnus of NASA's Astrobiology post-doctoral program and now assistant professor at the Georgia Institute of Technology. "You have these huge mountains on the sea floor, housing these incredible ecosystems."

In March, Glass presented some of her work on methane and microbes in the second lecture for NASA's Astrobiology Postdoctoral Program seminar series. In her talk, "Microbes, Methane, and Metals," Glass discussed the importance of metals as nutrients for these microbes.

Glass's work has a broader implication for understanding greenhouse gas cycles and climate change. Methane is a greenhouse gas that is approximately 25 times more potent than carbon dioxide. Recently, atmospheric methane has been increasing after a decade-long hiatus. While scientists aren't entirely sure why, they suspect a combination of methane-producing microbes in wetlands and the warming of high latitude permafrost. What's more, recent findings suggest that methane-spewing microbes may have contributed to our Earth's biggest extinction, the "Great Dying," 250 million years ago.

The methane-eating microbes that Glass studies play an important role in the methane cycle, keeping in check additional release of methane from cold seeps, where it is stored as an ice-like structure that slowly trickles through the sea floor.

Glass first learned about these ecosystems while studying oceanography in college, and quickly became fascinated by them. "I could gush poetically," she says, offering the link to a long piece she wrote for the magazine Northwest Science and Technology in 2006 (Methane Mimosas on Ice).

But she did not get to work on them until years later, when she became an Astrobiology NPP postdoc in the lab of Victoria Orphan, a geobiologist at the California Institute of Technology. On her first day, Glass and her new colleagues boarded the RV Atlantis on a scientific expedition off of Oregon's coast. Using the Remotely Operated Vehicle Jason, they collected microbes and sediments from the sea floor.

From these samples emerged a surprising discovery.

The group found evidence of a new microbial enzyme that seems to use the trace metal tungsten instead of molybdenum, the metal more commonly found in cold seep environments. Previously, tungsten had only been found in microbes living at high temperatures, such as the boiling waters of hydrothermal vents. The group's findings were published last year in the journal Environmental Microbiology.

"It's a very unique chemical environment, with a lot of sulfur," Glass says. "We think that tungsten might just be more bio-available in these highly sulfidic conditions."

"Overall, we're hoping to get a better understanding of alternative pathways of greenhouse gas cycling," she says. "Our main goal here was to understand how the environment in these deep sea methane seeps influences microbe metabolism, and specifically the trace-metal chemistry. And no one had really looked into these specific chemicals before."

In collaboration with colleagues at Georgia Tech as well as Sean Crowe of the University of British Columbia and David Fowle of the University of Kansas, Glass has now begun new studies in Lake Matano, Indonesia as an analogue for oceans on early Earth. The deep waters of Lake Matano are poor in oxygen and rich in iron and methane, factors likely characteristic of ancient oceans.

"We're looking to pull out unique microbes from these sediments," she says. "And so far, the evidence suggests that microbes may be coupling methane and iron redox cycles to survive at the bottom of Lake Matano."

While excessive methane release in the atmosphere could be catastrophic for life today, it may not always have been the case. On early Earth, our Sun was 30 percent fainter than it is today. Scientists believe that atmospheric methane may have kept the Earth warm enough to prevent water from freezing, enabling the emergence and evolution of early life.

What's more, these systems don't depend on oxygen, Glass explains. So the microbe-methane relationship likely developed early in Earth's history before the rise of oxygen.

They could also serve as analogues for worlds beyond our Earth. Methane has been detected in the atmosphere of other planets. Methane lakes have also been spotted on Titan, Saturn's largest moon, making it an intriguing candidate for life elsewhere.


Related Links
Astrobiology Magazine
Water News - Science, Technology and Politics

Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks DiggDigg RedditReddit GoogleGoogle

Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News

Octillions of microbes in the seas: Ocean microbes show incredible genetic diversity
Washington DC (SPX) May 01, 2014
The smallest, most abundant marine microbe, Prochlorococcus, is a photosynthetic bacterial species essential to the marine ecosystem. It's estimated that billions of the single-celled creatures live in the oceans, forming the center of the marine food web. They occupy a range of ecological niches based on temperature, light, water chemistry and interactions with other species. But th ... read more

North Shore Deploys Mutualink's Emergency Communications Platform in 15 Hospitals

350 dead, hundreds missing in Afghan landslide village

No answers, only hope as MH370 China father heads home

Malaysia Airlines to end hotel stays for MH370 families

Sierra Nevada Corporation Completes and Delivers Satellites for ORBCOMM Mission 1 Launch

Coming soon: a brain implant to restore memory

Raytheon developing the world's most advanced digital radar

Training range simulators in Britain, Canada getting support from Cubic

Microscopic Organism Plays a Big Role in Ocean Carbon Cycling

Octillions of microbes in the seas: Ocean microbes show incredible genetic diversity

Probing the Depths of the Methane World

Sustainable barnacle-repelling paint

Network for tracking earthquakes exposes glacier activity

Krypton-dating technique allows researchers to accurately date ancient Antarctic ice

Cougars' diverse diet helped them survive the Pleistocene mass extinction

Ancient sea-levels give new clues on ice ages

Danone says will buy New Zealand dairy factories

Corn crops increasingly vulnerable to hot, dry weather

U.S. corn yields are increasingly vulnerable to hot, dry weather

Saving Crops and People with Bug Sensors

Deep origins to the behavior of Hawaiian volcanoes

Australian tsunami database reveals threat to continent

Magma in Mount St. Helens rising, but no risk of eruption

Odds of storm waters overflowing Manhattan seawall up 20-fold

EU CAR force operational, at Bangui airport: sources

Libya security forces lose 9 dead in Benghazi clashes

China's premier Li Keqiang set for first Africa trip

War, late rains spark Somalia 'crisis' warning

DNA 'Sat Nav' directs you to your ancestor's home

Neanderthals were not inferior to modern humans

Extreme sleep durations may affect brain health in later life

Brain Does Not Work The Way A Computer Does Recognizing Speech

The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.