Yellowstone Hot Springs Organisms Could Aid Search for Alien Life

Researchers from Montana State University have uncovered two previously unknown groups of microbes in the hot springs of Yellowstone National Park. This significant discovery was detailed in the journal Nature on July 24, in a study titled “Cultivation and visualization of a methanogen of the phylum Thermoproteota.” The new microbial groups are named Methanomethylicia and Methanodesulfokora and are identified as methanogens, which are single-celled organisms that produce methane.

Methanogens, first identified by scientists in 1933, are unique bacteria that produce methane by reducing carbon dioxide, unlike humans and other animals that consume food, inhale oxygen, and exhale carbon dioxide. This research could impact the search for extraterrestrial life and efforts to combat climate change.

Previously, it was believed that all methane-producing bacteria belonged to a single phylum called Euryarchaeota. The discovery of these new groups confirms a greater diversity among methanogens, which had only been identified through DNA samples until now.

Methane is a potent greenhouse gas, 28 times more effective than carbon dioxide at trapping heat in the atmosphere. Microbiologist Roland Hatzenpichler of Montana State, a co-author of the study, emphasized that prior to this discovery, the only information about these organisms came from their DNA. No one had seen these methanogens or knew if they used their methanogenesis genes or grew by other means.

Two research groups, one from China and the other from the US, have successfully cultivated these microorganisms in the lab, verifying their methane production. Methanogens are responsible for producing 70 percent of the world’s methane. Hatzenpichler highlighted the significance of this finding, noting that methane levels are increasing at a much faster rate than carbon dioxide, with human activities contributing significantly to methane emissions.

Scientists are investigating whether Methanomethylicia can grow using methanogenesis in non-extreme conditions or if they use another method. Understanding this could help alter their habitats to reduce methane emissions. Hatzenpichler speculates that these organisms might switch between producing methane and other growth mechanisms, but further research is needed to determine when and how they contribute to methane cycling.

The study also has implications for the search for extraterrestrial life. According to Newsweek, NASA’s exobiology program, which partially funded the research, is interested in methanogens because they offer insights into early Earth life and the potential for life on other planets and moons where methane is present.