Methane-eating organism a shapeshifter

A microorganism that feeds on methane to reduce the release of gas into the atmosphere is also a shapeshifter, a study has found.

The microorganism, known as Candidatus Methanoperedens nitroreducens (or Ca. M. nitroreducens), is a critical life form in maintaining the earth's climate.

It feeds on methane produced in the environment, dramatically reducing its release into earth's atmosphere, found the QUT Centre for Microbiome Research study.

According to National Geographic, methane is a potent greenhouse gas that originates from lakes and swamps, natural-gas pipelines, deep-sea vents, and livestock that traps heat in earth's atmosphere.

It says methane is about 28 times more powerful than carbon dioxide at warming the earth on a 100-year timescale and more than 80 times more powerful over 20 years.

"As a greenhouse gas, methane is second only to carbon dioxide in contributing to climate change, making these organisms vital for maintaining earth's climate," QUT researcher Simon McIlroy said.

The microorganism performs anaerobic methane oxidation and nitrate reduction - effectively feeding on the methane.

"This species is globally distributed in natural environments where organic carbon is present in the absence of oxygen," Dr McIlroy said.

"These microorganisms feed on methane produced in the environment, dramatically reducing its release into earth's atmosphere."

However, the study revealed the microorganism rapidly changes its shape and metabolism, "stealing" genes from other species to enable it to use different nutrients.

"We found in the current study that all the observed Ca. M. nitroreducens cell types were genomically identical, despite having different shapes and gene expression profiles associated with carbon metabolism, movement and cell division,'' he said.

"The different cell types of this single microbial species appear to perform different functional roles, enabling the species to rapidly respond to and endure sub-optimal environmental conditions."

Dr McIlroy said the study was the first to demonstrate distinct life stages for a member of the Archaea within a complex microbial community.

"These findings have general implications for our understanding of how microorganisms adapt to changes in their environment," he said.