Earth Organisms Survive Under Low-Pressure Martian Conditions

Photo by Matt Reynolds

Rebecca Mickol, University of Arkansas.

FAYETTEVILLE, Ark. – New research at the University of Arkansas suggests that methanogens – among the simplest and oldest organisms on Earth – could survive on Mars.

Methanogens, microorganisms in the domain Archaea, use hydrogen as their energy source and carbon dioxide as their carbon source, to metabolize and produce methane, also known as 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.

Methanogens are anaerobic, so they don’t require oxygen. They don’t require organic nutrients, either, and are non-photosynthetic, indicating they could exist in sub-surface environments and therefore are ideal candidates for life on Mars.

Rebecca Mickol, a doctoral student in space and planetary sciences, found that in the laboratory, 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,” Mickol said. “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.”

Mickol, who has previously found that two species of methanogens survived Martian freeze-thaw cycles, conducted both studies with Timothy Kral, professor of biological sciences in the Arkansas Center for Space and Planetary Sciences and lead scientist on the project. She is presenting her work at the 2015 General Meeting of the American Society for Microbiology, being held May 30-June 2 in New Orleans.

Kral has been studying methanogens and examining their ability to survive on Mars since the 1990s. In 2012, he received a three-year, nearly $392,000 grant from the NASA Exobiology Program to study methanogens.

The four species of methanogens Mickol studied were: Methanothermobacter wolfeii, Methanosarcina barkeri, Methanobacterium formicicum, Methanococcus maripaludis.

About the Arkansas Center for Space and Planetary Sciences: The Arkansas Center for Space and Planetary Sciences, founded in 2000, is an interdisciplinary research institute at the University of Arkansas with 18 graduate students and nearly $3 million in awarded grants.

About the University of Arkansas: The University of Arkansas provides an internationally competitive education for undergraduate and graduate students in more than 200 academic programs. The university contributes new knowledge, economic development, basic and applied research, and creative activity while also providing service to academic and professional disciplines. The Carnegie Foundation classifies the University of Arkansas among only 2 percent of universities in America that have the highest level of research activity. U.S. News & World Report ranks the University of Arkansas among its top American public research universities. Founded in 1871, the University of Arkansas comprises 10 colleges and schools and maintains a low student-to-faculty ratio that promotes personal attention and close mentoring.