November 1, 2010 — Ottawa, Ontario
Canadian microbiologists exploring a salty subzero Arctic spring have found bacteria that might be telling us something about life on Mars.
The unexpected discovery of methane-consuming bacteria was made at the Lost Hammer Spring on Axel Heiberg Island, in Nunavut Territory. Dr. Lyle Whyte, a McGill University microbiologist leading this work, calls the Lost Hammer Spring the most extreme subzero and salty environment he's ever found. Dr. Whyte has discovered two types of bacteria there that feed off the methane and breathe something other than oxygen - since there is no usable oxygen in the spring. But what has this got to do with life on Mars?
According to Dr. Dale Andersen, a scientist from the California-based SETI Institute, this discovery suggests that similar bacterial life could exist on the Red Planet. In many ways, the environmental conditions on Mars resemble the Canadian Arctic. Recent data collected by NASA suggest that Mars has pockets of methane and frozen water, and temperatures in the same range as the Lost Hammer Spring. The idea is that, if such bacteria could thrive in Mars-like conditions here on Earth, then Mars may support such life.
NRC microbiologist Dr. Charles Greer has completely different reasons for being interested in this bacterial discovery - reasons that are much more down to Earth.
Dr. Greer's role in the Lost Hammer Spring research was to identify the types and characterize the attributes of microorganisms that live in both unique and harsh environments. At NRC, his research focuses mainly on the role that microorganisms can play in the remediation of contaminated soil and water. But he also sees the potential role that methane-eating bacteria could play in reducing the impact of climate change.
"As the temperature increases, permafrost in the North is melting. If the land becomes water saturated, carbon trapped in the permafrost is more likely to be emitted as methane than carbon dioxide," says Dr. Greer. "In terms of heat retention, methane is a far more significant greenhouse gas than carbon dioxide."
Drs. Whyte and Greer are both interested in discovering more about the microorganisms found in permafrost and the top layers of soil, how active these microorganisms are at below-zero temperatures, and how much more active they might become when the temperature rises.
"Microorganisms that consume methane could have a special role to play in mitigating methane emissions and their impact on climate change, especially if we can find a way to increase their activity," adds Dr. Greer.
The research was published in May 2010 in the International Society for Microbial Ecology Journal.
The project was supported by several organizations including the Canadian Space Agency, NASA, the Natural Sciences and Engineering Research Council of Canada, the Canadian Polar Continental Shelf Project, McGill University's Arctic Research Station, the Department of Indian and Northern Affairs, and the Fonds Québécois de la Recherche sur la Nature et les Technologies.
