University of California, Riverside researchers will soon be analyzing microorganisms from a vast Antarctic lake in an effort to unlock the mystery of how life adapts to extremely harsh environments.
Assistant Professor of Environmental Sciences Brian Lanoil is spearheading a project that will probe the life found in Lake Vostok, the world's seventh largest lake, a Great Lakes-size body of fresh water trapped under 4 kilometer-thick polar ice sheet.
The goal is to reconstruct the genomes of the microorganisms that live in the lake in order to find clues to how they have been able to withstand the bitter cold, total darkness, low nutrients and high oxygen levels. The project scientists also want to know how these organisms have survived in this bleak landscape over evolutionary and geologically significant lengths of time. The lake is estimated to have been buried under ice for at least 15 million years and is thought to have been isolated from the external environment over the last 1.5 million years.
"Previous studies showing that microorganisms live in this extremely isolated and severe environment really show the tenacity of life: wherever life is possible, we find it," Lanoil said. "Our study will help provide insight into how microorganisms manage to survive in these conditions."
Funded with a two-year, $481,000 National Science Foundation grant, Lanoil will be working with colleagues Craig Cary at the University of Delaware and Philip Hugenholtz at the Lawrence Berkeley National Laboratory. They will compare their results with a similar study carried out by Sergei Bulat at the Russian Academy of Sciences.
The NSF funding is part of a special Congressional appropriation in support of the International Polar Year (IPY). The IPY, which will extend from March 2007 through March 2009, is an international scientific campaign to learn more about polar science, to improve understanding of the critical role of the polar regions in global processes, and to educate students, teachers, and the public about the polar regions and their importance to global systems. It is the first such effort in 50 years when, in 1957, the first IPY laid the basis for much of what is known today about the effects of polar regions on global climate and helped establish the U.S. presence in Antarctica.
Because of concerns over contaminating the pristine environment, lake water is not available for study, but lake water that has frozen into the ice cap is available and will be studied from samples at the National Ice Core Laboratory in Denver.
Lanoil's lab at UCR will extract the DNA and do the initial analysis of the core samples. These DNA samples will be sent to the University of Delaware and to Lawrence Berkeley National Laboratory for additional work, with all three groups focusing on different genes from the sample.
They expect to find minimal genetic diversity among the microbes and to find features, such as super-efficient metabolisms and other genetic adaptations that allow them to live under extremely adverse ecological conditions.
In the 1960s, Russian scientists suspected that water lay beneath the ice sheet based on results from seismic soundings. In the 1970s, a joint U.S.-U.K.-Danish airborne radar mapping project discovered areas with flat reflections from the bottom of the ice sheet suggesting water beneath the ice. The full size of Lake Vostok, about the size of Lake Ontario, was first revealed in 1996 by the flat ice sheet surface mapped from the European ERS-1 satellite.