A team of Pomona College researchers is taking a closer look at tiny microbes that survive in the dark, 150 to 200-degree Fahrenheit environment deep beneath the surface of the Earth, feeding on oil and “breathing” sulfur compounds and metals in this largely oxygen-free realm — mimicking the beginnings of life on earth and potentially life on other planets similar to ours.
Professors EJ Crane, Andre Cavalcanti and Matthew Sazinsky are the recipients of a three-year $515,000 National Science Foundation grant for their work studying the “thriving microbial community that lives independent from our sun-driven surface world,” an environment that accounts for a third of the Earth's bio mass. If oxygen is the key to life above the surface, sulfur plays a similar role deep beneath the Earth's surface. Because the subsurface is shut off from the atmosphere and oxygen, it means these microbes need to find alternative compounds to “breathe” (reduce), in order to create the energetic cycles necessary to drive life. Sulfur is one such element – sulfur and oxygen share many characteristics, including their ability to serve as “breathable” substrates. Despite the importance of sulfur reduction to life in the subsurface, we are only beginning to understand this chemistry and the microbes that perform it.
The work funded by this grant covers many different disciplines. Student researchers will be performing chemical studies on the sulfur compounds found in the deep, hot subsurface environment, biological studies on microbes that are there, and genetic studies on the entire population of microbes in the deep subsurface.
The insights and implications of this research could offer a better understanding of life’s start here and life elsewhere.
“These environments could be very much like the early earth, mimicking the conditions in which life got a start here on earth, and even how life might develop on similar environments elsewhere in the universe,” says Crane, lead researcher.