Who Lives in a Hydrothermal Vent Under the Sea?

Thanks to the Penn Undergraduate Climate Action Grant, Preethi Kumaran, C’21, was able to spend her summer studying hydrothermal vent microbes from the bottom of the ocean. Working in the lab of Ileana Pérez-Rodríguez, Assistant Professor of Earth and Environmental Science and Elliman Faculty Fellow, Kumaran learned how to sustain and cultivate test tubes of anaerobic microorganisms that were obtained during some of the professor’s deep sea dives. Due to the extreme conditions (of pressure, temperature, and chemical environments) the organisms are acclimated to living in, growing and studying them in a lab setting is a difficult task, resulting in very few of them having ever been identified. The purpose of these attempts is to add to the existing knowledge base of known microorganisms, and occasionally to find further applications for them.

“We were trying to see if we could isolate microorganisms that we already have in the database or try to find something new,” says Kumaran. “It’s a really big world out there and there’s not a big chance that everyone has samples from the exact same spot, so there’s a likelihood of finding something new every time.”

Under mentorship from Pérez-Rodríguez, she spent months playing with temperature, types of growth media, and other conditions, all the while forming unexpected precision skills in preventing these organisms from contacting oxygen, and building an army of these test tubes over the course of the summer. The other half of her time was spent in the lab basement, learning microscopy skills by analyzing microorganism growth and type. After countless trials, one test tube finally had sustained growth. With renewed excitement the sample DNA was sent off to be sequenced, the results of which suggest a “potentially novel deep-branching bacterial species,” says Pérez-Rodríguez. The lab is currently trying to recreate the results to better understand them.