In the vast spectrum of Earth’s inhabitants, humans enjoy a comfortable existence compared to some extreme organisms. While we don’t endure the vacuum of space like tardigrades or cling to scorching hydrothermal vents like extremophile bacteria, one microbe, Geobacter sulfurreducens, thrives in anaerobic environments deep within the Earth, presenting scientists with a captivating puzzle of survival.

Researchers have long been intrigued by Geobacter’s ability to flourish underground, and recent discoveries shed light on its remarkable adaptation—a microbial electric grid beneath our feet. Geobacter employs nanowires, minuscule electric “hairs,” to transfer excess electrons, connecting with minerals and other microbes to create a biological network conducive to life. Yet, the origin of these electric charges has remained a mystery—until now.

A groundbreaking study by scientists from Yale University and the NOVA School of Science and Technology in Lisbon, Portugal, identified a specific family of proteins, cytochromes, responsible for powering Geobacter’s underground electric realm. These proteins act as charging plugs for the nanowires, facilitating the release of excess electrons generated during metabolic processes. Published in Nature Communications, the study unveils the intricate bioelectrical properties of these microbes.

“Common soil and marine microbes of the family Geobacteraceae play crucial roles in diverse environments and biotechnological applications,” the researchers stated. “Structures of these nanowires reveal interconnected chains of cytochromes, promoting rapid and insulated electron conduction over significant distances.”

Understanding Geobacter’s bioelectrical prowess holds immense technological and environmental implications, including advancements in biomaterials and bioenergy production. Despite their minuscule size—Geobacter is three to five nanometers wide, with nanowires extending just 20 nanometers beyond the microbe—they wield significant influence over Earth’s greenhouse gas processes.

“Microbes play a pivotal role in mitigating methane emissions, a potent greenhouse gas,” noted a Yale press statement. “Understanding their metabolic processes offers potential solutions to combat climate change, with microbes on Earth’s surface contributing significantly to methane emissions into the atmosphere.”

As scientists delve deeper into the electric wonders of Geobacter sulfurreducens, the possibilities for harnessing their capabilities for technological innovation and environmental stewardship become increasingly promising.

By Impact Lab