December 07, 2007 —
Methane-gobbling bacteria could aid climate change battle
A
new species of bacteria discovered living in one of the most extreme
environments on Earth could yield a tool in the fight against global
warming. In a paper published today in the prestigious science journal Nature, U
of C biology professor Peter Dunfield and colleagues describe the
methane-eating microorganism they found in the geothermal field known
as Hell’s Gate, near the city of Rotorua in New Zealand. It is the
hardiest "methanotrophic" bacterium yet discovered, which makes it a
likely candidate for use in reducing methane gas emissions from
landfills, mines, industrial wastes, geothermal power plants and other
sources.
"This is a really tough methane-consuming organism that
lives in a much more acidic environment than any we’ve seen before,"
said Dunfield, who is the lead author of the paper. "It belongs to a
rather mysterious family of bacteria (called Verrucomicrobia) that are
found everywhere but are very difficult to grow in the laboratory."
Methanotrophic
bacteria consume methane as their only source of energy and convert it
to carbon dioxide during their digestive process. Methane (commonly
known as natural gas) is 20 times more potent a greenhouse gas than
carbon dioxide and is largely produced by decaying organic matter.
Scientists have long known that vast amounts of methane are produced in
acidic environments, not only geothermal sites but also marshes and
peat bogs. Much of it is consumed by methanotrophic bacteria, which
serve an important role in regulating the methane content of the
world’s atmosphere.
"Scientists are interested in understanding
what conditions cause these bacteria to be more or less active in the
environment" says Dunfield, "Unfortunately, few species have been
closely studied. We now know that there are many more out there."
Dunfield
has tentatively named the new bacterium Methylokorus infernorum to
reflect the ‘hellish’ location of its discovery where it lives in
boiling waters filled with chemicals that are toxic to most life forms.
The Maori caretakers of the site, the Tikitere trust, have supported
scientific study of the area. The study was conducted while Dunfield
was working for GNS Science, a geological research institute owned by
the New Zealand government. He recently joined the U of C’s Department
of Biological Sciences as a professor of environmental microbiology.
The
bacterium’s genome has been completely sequenced by researchers at the
University of Hawaii and Nankai University in China, which could help
develop biotechnological applications for this organism.
Dunfield
said he plans to pursue his work in Canada by hunting for new life
forms in extreme environments such as northern peatlands, the oilsands
of northern Alberta and the hot springs of Western Canada.
"Hot
springs are exotic and extreme habitats, where you find a lot of
bizarre organisms," he said. "Bacteria are a fascinating group to work
with because 95 per cent of them have never been studied in a lab and
we have very little idea about what this huge amount of biodiversity is
capable of."
Source : University of Calgary