Melbourne: Scientists have discovered two new clusters of microorganisms contributing to climate change, the second major breakthrough in 12 months towards mapping the tree of life.
The previously unknown group of methane-metabolising micro-organisms appeared to be ancient and widespread in nature, said Gene Tyson from the University of Queensland in Australia.
He said 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," said Tyson.
"This research expands our knowledge of the diversity of life on Earth and suggests we are missing other organisms involved in carbon cycling and methane production," he said.
Last year Tyson's lab was part of an international project which discovered a new group of methane-metabolising organisms called Bathyarchaeota, 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," he added.
The newly discovered group of methanogens so far contained five genomes but there could well be more, said lead author Inka Vanwonterghem from the Australian Centre for Ecogenomics.
"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 research was published in the journal Nature Microbiology.