Astrobiologists supported in part by the NASAAstrobiology Institute have performed a detailed analysis of the biochemistry that helps microorganisms thrive in extremely cold environments around methane seeps on the ocean floor.

The study was led by Jennifer Glass at Georgia Tech, and reveals previously unknown details about how two symbiotic microbes (one bacteria and one archaea) ‘eat’ methane trapped in methane hydrate crystals deep below the ocean. The process centers around a unique enzyme that uses the rare trace metal tungsten. This is the first time that organisms have been found to use tungsten enzymes in such a low temperature environment.

Methane hydrate crystals are formed in the low temperatures and high pressures found at the seafloor. As the Earth’s oceans warm, some scientists believe that massive amounts of methane could be released and ultimately reach the atmosphere. Studying how microbes process methane hydrates in this extreme environment will help astrobiologists understand how the deep sea ecosystem could change in the future.

Jennifer Glass was a NASA Astrobiology post-doctoral fellow at the California Institute of Technology when conducting this research. She is now an assistant professor in the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology.

The paper, “Geochemical, metagenomic and metaproteomic insights into trace metal utilization by methane-oxidizing microbial consortia in sulphidic marine sediments,” was published on November 14th in the journal Environmental Microbiology.