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- Aug 18, 2002
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http://www.thedenverchannel.com/news/3297237/detail.htmlBizarre Yellowstone Virus May Be Key To Our Past
Heat-Loving Virus Clue To First Life On Earth?
POSTED: 1:23 pm MDT May 12, 2004
BILLINGS, Mont. -- Scientists at Montana State University in Bozeman say they have discovered a heat-loving, acid-dwelling virus that could help provide a link to ancient life on Earth.
The virus found in Yellowstone National Park could help to understand a common ancestor that scientists believe was present before life split into forms such as bacteria, heat-loving organisms and the building blocks that led to plants and animals, researchers said.
"It's a clue that helps you say, `Yeah, there probably was a common ancestor at some point or sets of ancestors,"' said George Rice, one of the MSU scientists who participated in the study. "It's food for thought."
The scientists' discovery was published in the May 3 issue of the Proceedings of the National Academy of Sciences.
Rice began hunting for heat-loving "thermophilic" viruses in Yellowstone five years ago. In 2001, he and others found several apparently unique viruses associated with an organism living near Midway Geyser Basin where temperatures ranged from 158 to 197 degrees Fahrenheit.
"It was basically something living in boiling acid," Rice said.
Although several new viruses were discovered, one in particular caught their eye.
After characterizing the structure and genome of the virus, they found that its protein shell was similar to a bacterial virus and an animal virus. The similarity suggests to the scientists that the three viruses may share a common ancestor that predates the branching off of life forms more than 3 billion years ago.
"This is something that was predicted but hadn't been shown before," Rice said.
For a long time, scientists classified all life forms as plant or animal. That classification system expanded as more life forms were discovered. Eventually, biologists divided life into five kingdoms _ plants, animals, bacteria, fungi and protists.
A more recent approach divides life into three domains: bacteria, eukarya _ which includes plants, fungi, animals and others _ and archaea, which means ancient.
Archaea, similar to bacteria, is likely the least understood of the domains, according to the paper's authors. Archaea may have been among the first forms of life on Earth. Able to thrive in the hot, gaseous and volcanic terrain of early Earth, they could also survive in the very inhospitable geothermal features of the Yellowstone of today.
Now that scientists know the Yellowstone virus's ancient structure seems to span all three domains of life, scientists plan additional studies on its genes to figure out what they tell the virus to do.
"Anywhere there's life, we expect viruses," Young said. "They are the major source of biological material on this planet."
Researchers said the virus and others found at Yellowstone will give researchers a hand in the search for life on other planets, including Mars.
"These bugs are living and doing business in a harsh environment," Rice said. "This may be clues about what to look for."