Subscribe to our free daily newsletters
. Military Space News .




Subscribe to our free daily newsletters



Locked In Glaciers And Ancient Microbes May Return To Life

Not only were the microorganisms in oldest ice slow to grow, the researchers were unable to identify them as they grew, because their DNA had deteriorated. In fact, the DNA in the five samples examined showed an "exponential decline" after 1.1 million years, "thereby constraining the geological preservation of microbes in icy environments and the possible exchange of genetic material to the oceans."
by Staff Writers
New Brunswick, NJ (SPX) Aug 08, 2007
The DNA of ancient microorganisms, long frozen in glaciers, may return to life as the glaciers melt, according to a paper published online this week in the Proceedings of the National Academy of Sciences by scientists at Rutgers, The State University of New Jersey, and Boston University. The article is scheduled to appear in the print edition on Tuesday, Aug. 14.

The finding is significant, said Kay Bidle, assistant professor of marine and coastal sciences at Rutgers, because scientists didn't know until now whether such ancient, frozen organisms and their DNA could be revived at all or for how long cells are viable after they've been frozen. Bidle is lead author of the article, "Fossil Genes and Microbes in the Oldest Ice on Earth."

Bidle and his co-authors, Rutgers colleague Paul Falkowski, SangHoon Lee of Korea's Polar Research Institute and David Marchant of Boston University - melted five samples of ice ranging in age from 100,000 to 8 million years old to find the microorganisms trapped inside.

The researchers wanted to find out how long cells could remain viable and how intact their DNA was in the youngest and oldest ice.

"First, we asked, do we detect microorganisms at all?" Bidle said. "And we did - more in the young ice than in the old. We tried to grow them in media, and the young stuff grew really fast. We recovered them [the microorganisms] easily; we could plate them and isolate colonies. They doubled every couple of days." By contrast, Bidle said, the microorganisms from the oldest ice samples grew very slowly, doubling only every 70 days.

Not only were the microorganisms in oldest ice slow to grow, the researchers were unable to identify them as they grew, because their DNA had deteriorated. In fact, the DNA in the five samples examined showed an "exponential decline" after 1.1 million years, "thereby constraining the geological preservation of microbes in icy environments and the possible exchange of genetic material to the oceans."

"There is still DNA left after 1.1 million years,' Bidle said. "But 1.1 million years is the 'half-life' - that is, every 1.1 million years, the DNA gets chopped in half."

Bidle said the average size of DNA in the old ice was 210 base pairs - that is, 210 units strung together. The average genome size of a bacterium, by comparison, is 3 million base pairs.

The researchers chose Antarctic glaciers for their research because the polar regions are subject to more cosmic radiation than the rest of the planet and contain the oldest ice on the planet.

"It's the cosmic radiation that's blasting the DNA into pieces over geologic time, and most of the organisms can't repair that damage."

Because the DNA had deteriorated so much in the old ice, the researchers also concluded that life on Earth, however it arose, did not ride in on a comet or other debris from outside the solar system. "...(T)he preservation of microbes and their genes in icy comets may have allowed transfer of genetic material among planets," they wrote. "However, given the extremely high cosmic radiation flux in space, our results suggest it is highly unlikely that life on Earth could have been seeded by genetic material external to this solar system."

The five ice samples used in the experiment were taken from two valleys in the Transantarctic Mountains by Marchant, the Boston University glaciologist. "He sent us blocks of ice,' said Bidle of Marchant. "Without them, we couldn't have done the work. Dave is also one of the few researchers who is knowledgeable about the age of the ice, and also important information about the formation and geology of the ice."

The actual melting of the ice, growing of microorganisms and examination of DNA was carried out by Bidle and Lee, who was a visiting researcher at Rutgers at the time. Falkowski co-directed the research and helped to write the paper. The work was funded by a grant to Falkowski and Bidle from the Gordon and Betty Moore Foundation.

Community
Email This Article
Comment On This Article

Related Links
Explore The Early Earth at TerraDaily.com



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


UQ Researchers Discover Some Of The Oldest Forms Of Life
Brisbane, Australia (SPX) Aug 08, 2007
University of Queensland researchers have identified microbial remains in some of the oldest preserved organic matter on Earth, confirmed to be 3.5 billion years-old. The UQ team, led by School of Physical Sciences scientists Dr Miryam Glikson and Associate Professor Sue Golding as well as Associate Professor Lindsay Sly from the School of Molecular and Microbial Sciences, are the first to conclusively confirm the nature and source of the organic material.







  • China Shows Off New Military Hardware
  • USS Enterprise Arrives In Gulf
  • Proposed US Resolution Expresses Concern Over Moscow CFE Withdrawal
  • The Cultural Power Japan In The 21st Century

  • Russia Approves Mass Production Of Cutting-Edge Bulava Missile
  • Japan And Russia Discuss Second Phase Of North Korea Talks
  • Bush Levels Dubious Iran Nuclear Arms Charge
  • Fission And Fusion As Iran Fronts UN Nuclear Watchdog

  • US Pays Czechs To Destroy Cold War Missiles
  • Pakistan Tests Nuclear-Capable Cruise Missile
  • Lockheed Martin Tests Guidance Upgrade And Improved Software For ATACMS Block IA Unitary
  • Lockheed Martin Conducts PAC-3 Missile Test At White Sands Missile Range

  • Japan Buys Another Aegis System
  • Russia To Export S-400 Air Defense System From 2009
  • Northrop Grumman Delivers SBIRS GEO-1 Payload To Lockheed Martin
  • Democrats Back Israeli Missile Defense Program

  • Boeing Flies Blended Wing Body Research Aircraft
  • Steering Aircraft Clear Of Choppy Air
  • EAA AirVenture 2007
  • Sensors May Monitor Aircraft For Defects Continuously

  • Proxy Aviation Completes Cooperative Flight Demonstration OF UAV For USAF
  • Second Predator Crashes In Iraq In Two Days
  • US Navy Awards UCAS-D Contract To Northrop Grumman-Led X-47 Team
  • Boeing Awarded US Marine Corps Contract To Extend Scaneagle Services

  • The Good The Bad And The Ugly News From Iraq
  • Gates Points To Strategic Reassessment In Iraq But Will Retain Residual US Force
  • The Loss Of Will On Iraq
  • Benchmarks In Iraq Are A Necessary Service

  • Lockheed Martin Awarded Additional Five Billion Dollar Order For 60 F-22 Raptors
  • BAT System Helps Catch Bad Guys
  • Gulf War Illness Still Incurable
  • Raytheon Awarded Contract For US Navy Mine Hunting Sonar

  • The content herein, unless otherwise known to be public domain, are Copyright 1995-2006 - SpaceDaily.AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA PortalReports are copyright European Space Agency. All NASA sourced material is public domain. Additionalcopyrights 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 SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement