Ancient organisms growing in New Jersey laboratory

William Atkins
Tuesday, 07 August 2007 19:56

Science - Climate

Scientists removed samples of DNA and bacteria from ancient icy glaciers in the Beacon and Mullins valleys of Antarctica. The single-celled microbes (microscopic organisms) were then melted within their laboratory, and found to grow.               

Beacon Valley and Mullins Valley are within the Transantarctic Mountains, which basically divided Antarctica into two divisions: East Antarctica and West Antarctica.

Several microorganisms (which were between one-hundred thousand and eight-million years old) and one eight-million-old bacterium grew within the laboratory setting.

Paul Falkowski, one of the lead researchers, states that with global warming, more glacial ice will be melting. Thus, such action may likely awaken such microorganisms (such as bacteria and viruses) from their hibernation after millions of years. However, he does not believe such new organisms are a health concern to humans because water-based (marine) organisms are much less of a risk to human health than land-based (terrestrial) organisms. [New Scientist, "Eight-million-year-old bug is alive and growing", August 2007]
 

In addition, according to the research team, the DNA (deoxyribonucleic acid) from these microorganisms degrades over time. Approximately half of the DNA is degraded over about one million years. (DNA is the substance that holds an organism’s genetic information.) It is thought that the DNA is damaged primarily from cosmic rays, which impinge on the Earth from all corners of the universe.

Also, cycles of warming and freezing of glaciers has been happening for millions of years, so it is not unexpected that sleeping microorganisms have been introduced into the Earth’s environment throughout its history.
 

With global warming increasingly acting on the Earth, scientists are seeing a larger number of glacial meltings, which could likely result in larger numbers of microorganisms being released from their millions of year old hibernation.

In July 2007, a research team from the University of Copenhagen, Denmark, led by evolutionary biologist Eske Willerslev, reported that they had recovered DNA from Greenland that was about 800,000 years old, the oldest microorganism found at that time. This discovery by the Falkowski team, if proven true, could extend the record of the oldest microorganism found so far.

Such discoveries are important to the scientific community because it adds knowledge to how long the DNA of organisms can be frozen and revived.
 

These studies also add information as to whether life on the Earth began from genetic material embedded within comets that hit the planet early in its evolution. Since it has been found that DNA degrades fairly rapidly (due to the effects of cosmic radiation), it is less likely that life on Earth began from such extraterrestrial sources. However, insufficient information has been collected to yet make a valid determination.

The other collaborators in the study were Kay D. Bidle, Rutgers University (United States), Dave Marchant, of Boston University (United States), and SangHoon Lee, of the South Korea Polar Research Institute.

The results of their study have been written within the online August 6, 2007 issue of the Proceedings of the National Academy of Sciences.