Featured Research

from universities, journals, and other organizations

Life in the extreme: Hot acids and heavy metals make similar organisms deal with stress in different ways

Date:
September 24, 2012
Source:
North Carolina State University
Summary:
Life in extreme environments -- hot acids and heavy metals, for example -- can apparently make very similar organisms deal with stress in very different ways, according to new research.

Life in extreme environments -- hot acids and heavy metals, for example -- can apparently make very similar organisms deal with stress in very different ways, according to new research from North Carolina State University.

Related Articles


One single-celled organism from a hot spring near Mount Vesuvius in Italy fights uranium toxicity directly -- by eating the heavy metal and acquiring energy from it. Another single-celled organism that lives on a "smoldering heap" near an abandoned uranium mine in Germany overcomes uranium toxicity indirectly -- essentially shutting down its cellular processes to induce a type of cellular coma when toxic levels of uranium are present in its environment.

Interestingly, these very different responses to environmental stress come from two organisms that are 99.99 percent genetically identical.

In a paper published this week online in Proceedings of the National Academy of Sciences, NC State researchers show that these extreme organisms -- basic life forms called Archaea that have no nucleus and that are so tiny they can only be seen under a microscope -- can teach us a lot about how living things use different mechanisms to adapt to their surroundings.

The researchers, led by Dr. Robert Kelly, Alcoa Professor of Chemical and Biomolecular Engineering at NC State, exposed two very close relatives of thermoacidophilic Archaea -- they live in highly acidic environments with temperatures of more than 70 degrees Celsius, or about 160 degrees Fahrenheit -- to pure uranium. One, Metallosphaera sedula, metabolized the uranium as a way to support its energy needs.

That in itself was surprising to Kelly and his fellow researchers, as it was the first report that an organism can directly use uranium as an energy source.

"This could be a new way to mine uranium using microorganisms to release the metal from ores -- a process referred to as bioleaching," Kelly says of M. sedula.

Its genetic twin, Metallosphaera prunae, reacted very differently. When faced with pure uranium, it went into a dormant state, shutting down critical cellular processes that enable it to grow. When the toxic threat was removed, M. prunae rebooted its cellular processes and returned to its normal state.

Kelly hypothesizes that M. prunae is an offshoot of M. sedula, with just a small number of mutations, or changes, to its genome that allow it to react differently when faced with heavy-metal toxicity.

Kelly says the findings could also have implications for understanding how antibiotic resistance develops and operates in pathogens.

"We have come across a new model for how organisms learn how to live in an environment that would otherwise be deadly for them," he says.

Kelly adds that the study calls into question the ways that scientists classified living things before the rise of the genomic era.

"How do we classify microorganisms now that we can compare genomes so easily?" Kelly asks. "These are not different species by the classical definition because their genomes are virtually identical, but they have very different phenotypes, or lifestyles, when faced with stress."

The research was funded by the Defense Threat Reduction Agency in the U.S. Department of Defense, and by the National Institutes of Health.


Story Source:

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


Cite This Page:

North Carolina State University. "Life in the extreme: Hot acids and heavy metals make similar organisms deal with stress in different ways." ScienceDaily. ScienceDaily, 24 September 2012. <www.sciencedaily.com/releases/2012/09/120924152530.htm>.
North Carolina State University. (2012, September 24). Life in the extreme: Hot acids and heavy metals make similar organisms deal with stress in different ways. ScienceDaily. Retrieved December 22, 2014 from www.sciencedaily.com/releases/2012/09/120924152530.htm
North Carolina State University. "Life in the extreme: Hot acids and heavy metals make similar organisms deal with stress in different ways." ScienceDaily. www.sciencedaily.com/releases/2012/09/120924152530.htm (accessed December 22, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Monday, December 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Christmas Kissing Good for Health

Christmas Kissing Good for Health

Reuters - Innovations Video Online (Dec. 22, 2014) Scientists in Amsterdam say couples transfer tens of millions of microbes when they kiss, encouraging healthy exposure to bacteria. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Brain-Dwelling Tapeworm Reveals Genetic Secrets

Brain-Dwelling Tapeworm Reveals Genetic Secrets

Reuters - Innovations Video Online (Dec. 22, 2014) Cambridge scientists have unravelled the genetic code of a rare tapeworm that lived inside a patient's brain for at least four year. Researchers hope it will present new opportunities to diagnose and treat this invasive parasite. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
New Fish Species Discovered, Setting Record for World's Deepest

New Fish Species Discovered, Setting Record for World's Deepest

Buzz60 (Dec. 22, 2014) A new species of fish is discovered living five miles beneath the ocean surface, making it the deepest living fish on earth. Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com
Earthworms Provide Cancer-Fighting Bacteria

Earthworms Provide Cancer-Fighting Bacteria

Reuters - Innovations Video Online (Dec. 21, 2014) Polish scientists isolate bacteria from earthworm intestines which they say may be used in antibiotics and cancer treatments. Suzannah Butcher reports. 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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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