Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Unique microbes found in extreme environment

11.06.2012
Researchers who were looking for organisms that eke out a living in some of the most inhospitable soils on Earth have found a hardy few.
A new DNA analysis of rocky soils in the martian-like landscape on some volcanoes in South America has revealed a handful of bacteria, fungi, and other rudimentary organisms, called archaea, which seem to have a different way of converting energy than their cousins elsewhere in the world.

“We haven’t formally identified or characterized the species,” said Ryan Lynch, a microbiologist with the University of Colorado in Boulder who is one of the finders of the organisms, “but these are very different than anything else that has been cultured. Genetically, they’re at least 5 percent different than anything else in the [DNA] database of 2.5 million sequences.” The database represents a close-to comprehensive collection of microbes, he added, and researchers worldwide add to it as they publish papers about the organisms.

Life gets little encouragement on the incredibly dry slopes of the tallest volcanoes in the Atacama region, where Lynch’s co-author, University of Colorado microbiologist Steven Schmidt, collected soil samples. Much of the sparse snow that falls on the terrain sublimates back to the atmosphere soon after it hits the ground, and the soil is so depleted of nutrients that nitrogen levels in the scientists’ samples were below detection limits. Ultraviolet radiation in this high-altitude environment can be twice as intense as in a low-elevation desert. And, while the researchers were on site, temperatures dropped to -10 degrees Celsius (14 degrees Fahrenheit) one night, and spiked to 56° C (133° F) the next day.
How the newfound organisms survive under such circumstances remains a mystery. Although Lynch, Schmidt, and their colleagues looked for genes known to be involved in photosynthesis, and peered into the cells using fluorescent techniques to look for chlorophyll, the scientists couldn’t find any evidence that the microbes were photosynthetic. Instead, they think the microbes might slowly convert energy by means of chemical reactions that extract energy and carbon from wisps of gases such as carbon monoxide and dimethyl sulfide that blow into the desolate mountain area. The process wouldn’t give the bugs a high energy yield, Lynch said, but it could be enough as it adds up over time.

A scientific article about the new findings has been accepted for publication by the Journal of Geophysical Research-Biogeosciences, a journal of the American Geophysical Union.
While normal soil has thousands of microbial species represented in just a gram of soil, and garden soils even more, remarkably few species have made their home in the barren Atacama mountain soil, the new research suggests.

“To find a community dominated by less than 20 [species] – that’s pretty amazing for a soil microbiologist,” Schmidt said. He has studied sites in the Peruvian Andes where, four years after a glacier retreats, there are thriving, diverse microbe communities. But on these volcanoes on the Chile-Argentina border, which rise to altitudes of more than 6,000 meters (19,685 feet) above sea level and which have been ice-free for 48,000 years, the bacterial and fungal ecosystems have not undergone succession to more diverse communities.
“It’s mostly due to the lack of water, we think,” Schmidt said. “Without water, you’re not going to develop a complex community.”

“Overall, there was a good bit lower diversity [in the Atacama samples] than you would find in most soils, including other mountainous mineral soils,” Lynch said. That makes the Atacama microbes very unusual, he added. They probably had to adapt to the extremely harsh environment, or may have evolved in different directions than similar organisms elsewhere due to long-term geographic isolation.

Growth on the mountain might be intermittent, Schmidt suggested, especially if soils only have water for a short time after snowfall. In those situations, there could be microbes that grow when it snows, then fall dormant, perhaps for years, before they grow again. High elevation sites are great places to study simple microbial communities, ecosystems that haven’t evolved past the very basics of a few bacteria and fungi, he said. “There are a lot of areas in the world that haven’t been studied from a microbial perspective, and this is one of the main ones,” he said. “We’re interested in discovering new forms of life, and describing what those organisms are doing, how they make a living.”
Schmidt’s lab, along with others, is studying how microorganisms are dispersed — that is, how they travel from one site to another. There’s evidence that one common method of microbe transport is through the air – they’re caught up in winds, sucked up into clouds, form rain droplets, and then fall back to the ground somewhere else as precipitation. But on mountains like Volcán Llullaillaco and Volcán Socompa, the high ultraviolet radiation and extreme temperatures make the landscape inhospitable to outside microbes.

“This environment is so restrictive, most of those things that are raining down are killed immediately,” Schmidt said. “There’s a huge environmental filter here that’s keeping most of these things from growing.”

The next steps for the researchers are laboratory experiments using an incubator that can mimic the extreme temperature fluctuations to better understand how any organism can live in such an unfriendly environment. Studying the microbes and finding out how they can live at such an extreme can help set boundaries for life on Earth, Schmidt said, and tells scientists what life can stand. There’s a possibility that some of the extremophiles might utilize completely new forms of metabolism, whereby they convert energy in a novel way.

Schmidt is also working with astrobiologists to model what past conditions were like on Mars. With their rocky terrain, thin atmosphere, and high radiation, the Atacama volcanoes are some of the most similar places on Earth to the Red Planet.
“If we know, on Earth, what the outer limits for life were, and they know what the paleoclimates on Mars were like, we may have a better idea of what could have lived there,” he said.

Title:
“The potential for microbial life in the highest elevation (>6000 m.a.s.l.) mineral soils of the Atacama region
Authors:
Ryan C Lynch University of Colorado, Department of Ecology and Evolutionary Biology, Boulder, Colorado, USAAndrew J King Ecosystem Sciences, CSIRO Black Mountain, Acton, AustraliaMariá E Farías Laboratorio de Investigaciones Microbiologicas de Lagunas Andinas, Planto Piloto de Procesos Industriales Microbiologicas, CCT, CONICET, Tucuman, ArgentinaPreston Sowell Geomega, Boulder, Colorado, USAChristian Vitry Museo de Arqueologia de Alta Montana, Salta, ArgentinaSteve K Schmidt University of Colorado, Department of Ecology and Evolutionary Biology, Boulder, Colorado, USA

Contact information for the authors:

Ryan Lynch, Telephone: (303) 492-6248, Email: rlynch@Colorado.EDU;
Steve Schmidt, Telephone: (303) 492-6248, Email: Steve.Schmidt@Colorado.EDU
AGU Contact:
Kate Ramsayer
+1 (202) 777-7524
kramsayer@agu.org
CU-Boulder Contact:
Jim Scott
+1 (303-492-3114)
Jim.Scott@colorado.edu

Kate Ramsayer | American Geophysical Union
Further information:
http://www.agu.org
http://www.colorado.edu

More articles from Earth Sciences:

nachricht Filling the gap: High-latitude volcanic eruptions also have global impact
20.11.2017 | Institute of Atmospheric Physics, Chinese Academy of Sciences

nachricht Antarctic landscape insights keep ice loss forecasts on the radar
20.11.2017 | University of Edinburgh

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Antarctic landscape insights keep ice loss forecasts on the radar

20.11.2017 | Earth Sciences

Filling the gap: High-latitude volcanic eruptions also have global impact

20.11.2017 | Earth Sciences

Water world

20.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>