|Life Found Inside a Glacier|
By Kate Ruder
Posted: June 10, 2004
As in other studies of life in extreme environments, the scientists are searching for novel proteins that help the organisms survive and that could be used to make products such as antibiotics or cold-water detergents.
The hardy microbes survived with virtually no nutrients and withstood subzero temperatures and high pressure. Compared to other microbes they are ultra-small—most measure less than .2 microns (a micron is one-thousandth of a millimeter).
The microbes may be incredibly old. Geologists estimate that ice in the glacier is more than 120,000 years old, and it is possible that the microbes have been trapped in the ice the entire time. The organisms may lie dormant in the ice for thousands of years, or they may have an extremely slow metabolism. No one knows for sure.
Jean Brenchley of Pennsylvania State University in University Park and her colleagues reported the study’s initial findings recently at the American Society of Microbiology meeting in New Orleans, Louisiana.
The research was funded in part by the Astrobiology Center at Penn State. Learning about these organisms, known to scientists as extremophiles, could reveal clues about the boundaries of life on Earth, not to mention other planets such as Mars.
The researchers identified at least fifteen new species of microbes and are now analyzing DNA to classify and describe the organisms. Some species belong to a group of organisms, called Chrenarchaeaota, which thrive in a variety of climates including ice in Antarctica and volcanoes.
It took six months to grow some of the organisms in the laboratory. The cells were so stressed and damaged that they often did not grow even when they were fed the kinds of nutrients most microbes like.
Samples for the study were taken from ice collected from the Greenland Ice Sheet by geologists in the 1990s. It took the geologists five years of steady work to drill through the glacier; at 3,000 meters it was the deepest ice core ever recovered at the time. Samples of the ice core are now stored in underground trenches beneath the snow in Greenland.
To ensure that they did not contaminate samples, the Penn State scientists shaved off the outer surface of ice blocks, disinfected the area, and then used a specialized drill to remove the core. They melted the ice and filtered out the microbes from the water.