Featured Research

from universities, journals, and other organizations

Researchers Propose New Hypothesis On The Evolution Of Hot Springs Microorganisms

Date:
June 5, 2006
Source:
University of Georgia
Summary:
Since their discovery in the late 1970s, microorganisms known as archaea have fascinated scientists with their ability to thrive where no other life can -- in conditions that are extremely hot, acidic or salty.

These hot springs in Nevada, known as the Three Buddhas, harbor microorganisms known as archaea that thrive where no other life can. UGA researcher Chuanlun Zhang and his colleagues have proposed a new hypothesis on the origin of relatives of these hot springs microorganisms that live in low-temperature environments.
Credit: Image courtesy of University of Georgia

Since their discovery in the late 1970s, microorganisms known as archaea have fascinated scientists with their ability to thrive where no other life can – in conditions that are extremely hot, acidic or salty.

In the 1990s, however, scientists discovered that archaea occur widely in more mundane, low-temperature environments such as oceans and lakes. Now, researchers from the University of Georgia and Harvard University find evidence that these low-temperature archaea might have evolved from a moderate-temperature environment rather than from their high-temperature counterparts – as most scientists had believed. The results appear in the June 2006 issue of the journal Applied and Environmental Microbiology.

"Archaea represent one of the three domains of life on Earth," said Chuanlun Zhang, lead author of the study and associate professor of marine sciences at UGA. "Understanding their evolution may shed light on how all life forms evolve and interact with the environment through geological history."

Zhang and his colleagues examined a common group of archaea known as Crenarchaeota. He explains that the Crenarchaeota's low-temperature success may involve a unique molecule known as crenarchaeol that allows the organism's cell membrane to remain flexible in cooler environments.

The commonly held theory was that the crenarchaeol is a fairly new feature by evolutionary standards – evolving 112 million years ago during the Cretaceous period, the same period in which dinosaurs became extinct.

Zhang said the problem with this theory is that it puts the arrival of the organisms that contain crenarchaeol, Crenarchaeota, relatively late in geologic history and doesn't explain how they arose.

By analyzing 17 samples from springs in California, Nevada and Thailand as well as examining data published by other researchers in different environments, Zhang and his colleagues found that crenarchaeol was most commonly found at temperatures of about 104 degrees Fahrenheit. This is well above even the warmest sea surface temperatures during the Cretaceous period, leading them to conclude that the crenarchaeol – and by extension the groups of Crenarchaeota that have the molecule – evolved much earlier than previously thought.

Zhang's study puts the evolution of Crenarchaeota at 3.5 billion years ago, shortly after life began to emerge on Earth.

"Our study helped us to fill a significant gap about the evolution of Crenarchaeota," Zhang said. "The results show that the biomarker is not unique to the low-temperature environment. On the other hand, all known high-temperature (>158 F) Crenarchaeota don't have this biomarker. This suggests that the moderate-temperature Crenarchaeota may be the ancestors to the low-temperature species."

Zhang said understanding these ancient organisms is important to the planet's future. Most scientists believe that Crenarchaeota play an important role in fixing carbon dioxide, helping sequester the greenhouse gases from the atmosphere. Having a better understanding of how abundant Crenarchaeota are and how much carbon they remove can help scientists more accurately model the effects of global warming.

The study was supported by the National Science Foundation and the U.S. Department of Energy.


Story Source:

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


Cite This Page:

University of Georgia. "Researchers Propose New Hypothesis On The Evolution Of Hot Springs Microorganisms." ScienceDaily. ScienceDaily, 5 June 2006. <www.sciencedaily.com/releases/2006/06/060605191500.htm>.
University of Georgia. (2006, June 5). Researchers Propose New Hypothesis On The Evolution Of Hot Springs Microorganisms. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2006/06/060605191500.htm
University of Georgia. "Researchers Propose New Hypothesis On The Evolution Of Hot Springs Microorganisms." ScienceDaily. www.sciencedaily.com/releases/2006/06/060605191500.htm (accessed July 28, 2014).

Share This




More Plants & Animals News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Sea Turtle Hatchlings Emerge from Nest

Raw: Sea Turtle Hatchlings Emerge from Nest

AP (July 27, 2014) A live-streaming webcam catches loggerhead sea turtle hatchlings emerging from a nest in the Florida Keys. (July 27) Video provided by AP
Powered by NewsLook.com
Trees Could Save More Than 850 Lives Each Year

Trees Could Save More Than 850 Lives Each Year

Newsy (July 27, 2014) A national study conducted by the USDA Forest Service found that trees collectively save more than 850 lives on an annual basis. Video provided by Newsy
Powered by NewsLook.com
What's To Blame For Worst Ebola Outbreak In History?

What's To Blame For Worst Ebola Outbreak In History?

Newsy (July 27, 2014) A U.S. doctor has tested positive for the deadly Ebola virus, as the worst-ever outbreak continues to grow. Video provided by Newsy
Powered by NewsLook.com
The New York Times Backs Pot Legalization

The New York Times Backs Pot Legalization

Newsy (July 27, 2014) The New York Times has officially endorsed the legalization of marijuana, but why now, and to what end? Video provided by Newsy
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