ABOVE: Researchers probe alkaline pools in Yellowstone National Park for electrically active microbes.
PHUC T. HA, WASHINGTON STATE UNIVERSITY
Seven miles uphill from the nearest road, on the southern end of Yellowstone National Park, lies Heart Lake Geyser Basin, home to multiple hot springs but far from the typical tourist itinerary. Four years ago, Washington State University graduate student Abdelrhman Mohamed and several colleagues made the trek up, food packed in jars to avoid attracting bears, on the hunt for new bacterial species in the alkaline waters of the springs. Specifically, Mohamed was looking to sample species that were electrically active—that is, bacteria with metabolisms that depend on either donating electrons to or receiving them from their environment.
A 2016 review of studies carried out around the world identified 94 species of electrically active bacteria, but only a couple, Geobacter sulfurreducens and Shewanella oneidensis, have been thoroughly scrutinized, leaving many open ...
