News Release 


University of Washington


On Earth, scientists are studying the most extreme environments to learn how life might exist under completely different settings, like on other planets. A University of Washington team has been studying the microbes found in "cryopegs," trapped layers of sediment with water so salty that it remains liquid at below-freezing temperatures, which may be similar to environments on Mars or other planetary bodies farther from the sun.


"We study really old seawater trapped inside of permafrost for up to 50,000 years, to see how those bacterial communities have evolved over time," said lead author Zachary Cooper, a UW doctoral student in oceanography.

Cryopegs were first discovered by geologists in Northern Alaska decades ago. This field site in Utqia?vik, formerly known as Barrow, was excavated in the 1960s by the U.S. Army's Cold Regions Research and Engineering Laboratory to explore large wedges of freshwater ice that occur in the permafrost there. Subsurface brine was eventually collected from the site in the 2000s.

"The extreme conditions here are not just the below-zero temperatures, but also the very high salt concentrations," said Jody Deming, a UW professor of oceanography who studies microbial life in the Arctic Ocean. "One hundred and forty parts per thousand -- 14% -- is a lot of salt. In canned goods that would stop microbes from doing anything. So there can be a preconceived notion that very high salt should not enable active life."



Deming describes it as "exhilarating" because of the possibility for discovery.


"We're just discovering that there's a very robust microbial community, coevolving with viruses, in these ancient buried brines," Cooper said. "We were quite startled at how dense the bacterial communities are."


"The dominant bacterium is Marinobacter," Deming said. "The name alone tells us that it came from the ocean - even though it has been in the dark, buried in frozen permafrost for a very long time, it originally came from the marine environment."




For more information, contact Cooper at or Deming at
