Scientists Find Ancient Bacteria in Antarctica

PHILADELPHIA - Researchers at Rutgers University have found that, as the world warms, organisms that had been trapped in glacial ice, and which scientists are unfamiliar with, may come alive and resume growing.

Chunks of glacier dug up from Antarctica have revealed a startling cargo, Rutgers scientists announced Monday: bacteria that had apparently lain dormant in the ice for up to 8 million years. And despite their badly degraded DNA, some of the ancient microbes were able to reproduce after being warmed up in a New Brunswick, N.J., laboratory, and their genetic code has offered a snapshot of the distant past.

The team said its findings, published in the online edition of Proceedings of the National Academy of Sciences, could help tackle a wide range of scientific questions: from the threat of antibiotic-resistant bacteria to the mysteries of life on Mars.

Also on the horizon is the question of what would happen if glaciers, continuing to melt as a result of global warming, were to release DNA from long ago into the oceans.

Eight million years is by far the oldest estimate for microbial life frozen in ice, and Monday's report is being met with some skepticism. Yet the research draws on a broad range of evidence from geology and microbiology, winning admirers such as John C. Priscu, a microbial ecologist at Montana State University.

Barely a decade ago, this line of research was non-existent. Ice was thought to be virtually devoid of life, and thus Antarctica, with 70 percent of the world's fresh water locked in its frozen grip, was assumed to be a barren landscape. No more. Some researchers have speculated that, as glaciers continue to melt, the release of ancient microbes could be harmful to modern organisms.

But Kay Bidle, a Rutgers assistant professor of marine and coastal sciences, called that a remote possibility, as the recovered bacteria were not the kind that cause disease. Nor were numerous fragments of DNA from a variety of other bacteria found in the samples.

Tom Avril
Philadelphia Inquirer
Aug. 7, 2007 12:00 AM