Methanogens, one of the simplest and oldest microorganisms found on Earth can survive on Mars, a new study claims
The prospect of finding life on another planet is certainly a thrilling one. Over the years, scientists have tried to understand how life started on our own planet to predict how life could begin in other habitable planets. In particular, researchers have been interested in microbes living in “extreme” environments since some of these are thought represent some of the oldest forms of life on Earth.
These ancient and highly specialized organisms, called “extremophiles”, are thought to be able to grow pretty quickly in harsh conditions and are therefore an attractive candidate for the existence of life on other planets.
In line with this, a team of researchers at the University of Arkansas is referring to methanogens, which belong to the domain Archaea and are among the simplest and oldest organisms on Earth.They use hydrogen as their energy source and carbon dioxide (CO2) as their carbon source to metabolize and produce methane, a natural gas. Methanogens live in swamps and marshes, but can also be found in the gut of cattle, termites and other herbivores as well as in dead and decaying matter.
These simple organisms don’t require oxygen or organic nutrients to survive, as well as don’t undergo photosynthesis, indicating that methanogens are ideal for living in sub-surface environments such as those on Mars.
During this study, researchers found that in a laboratory setting, four species of methanogens survived low-pressure conditions that simulated a subsurface liquid aquifer on Mars. “These organisms are ideal candidates for life on Mars,” doctoral student Rebecca Mickol, who helped lead the research, said in a statement. “All methanogen species displayed survival after exposure to low pressure, indicated by methane production in both original and transfer cultures following each experiment. This work represents a stepping-stone toward determining if methanogens can exist on Mars.”
In previous research, Mickol also discovered that two species of methanogens survived Martian freeze-thaw cycles.
These findings were presented at the 2015 General Meeting of the American Society for Microbiology, being held May 30-June 2 in New Orleans.