"Acetate fermentation is the principal pathway accounting for as much as 95 percent of methane production in these cold environments," said co-Principal Investigator Jeffrey R. White, an IU School of Public and Environmental Affairs professor of environmental science. "In fact, some of these cold-loving, acetate-producing bacteria may be metabolically coupled to the methane-producing bacteria."
Pratt recently concluded a directorship of a NASA Astrobiology Institute team that studied energy and nutrient cycles that sustain life in the deep subsurface of Earth and, potentially, Mars. One of the fruits of that project was the discovery of bacteria on Earth that live kilometers below ground, in solid rock, and use the byproducts of irradiated water as a source of energy.
The connection between Earth and environs elsewhere in the solar system is a necessary part of astrobiology. We only know of life on our own planet, so the conditions that support life on Earth are our only point of reference for what's possible on Mars, Europa, and Enceladus, the three bodies currently deemed most likely to harbor (or to have once harbored) life.
"Our work on methane cycling in warming tundra ecosystems fits well with the objectives for exploration of methane cycling on Mars -- a target of the upcoming missions," White said.
The study of global climate change on methane production is also of interest to researchers whose chief and perhaps only interest is what's happening on our planet.
"One other key aspect of this project is the ASTEP requirement for the field campaign to address an important Earth science question," Pratt said. "Our proposal was competitive because of the importance of documenting how methane is released from permafrost settings on Earth during a tim
|Contact: David Bricker|