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Ancient Microbes Contributing to Climate Change

Scientists have discovered a major group of organisms that contribute to climate change. The previously unknown group of methane-metabolising microorganisms, described in Nature Microbiology (http://tinyurl.com/grgylll), appear to be ancient and widespread in nature.

Deputy Head of The University of Queensland’s Australian Centre for Ecogenomics, Prof Gene Tyson, said that methane-producing and -consuming organisms played an important role in greenhouse gas emissions and consumption, contributing to climate change. “The environments in which the new methane-producing cluster is found includes wetlands, lake and river estuary sediments, mud volcanoes and deep-sea vents,” he said.

“This research expands our knowledge of diversity of life on Earth, and suggests we are missing other organisms involved in carbon cycling and methane production.”

Last year Tyson’s lab was part of an international project that discovered a new phylum of methane-metabolising organisms called Bathyarchaeota, which are also found in a wide range of environments. “Traditionally, these type of methane-metabolising organisms occur within a single cluster of microorganisms called Euryarchaeota,” he said. “We have now found two new clusters of microorganisms, leading us to wonder how many other types of methane-metabolising microorganisms are out there.”

Lead author of the paper, Dr Inka Vanwonterghem, said the newly discovered group of methanogens so far contained five genomes but there could well be more. “There are many questions we will need to answer in future, including ‘can these organisms be grown in the lab and at large scale to produce methane; what is their role in the global carbon cycle and climate change; and what is the evolutionary history of these organisms?’” she said.

The researchers proposed that the new phylum be called Verstraetearchaeota after Prof Willy Verstraete, an eminent microbiologist at Ghent University in Belgium.