The cooling of Electrons in Bacterial Nanowires Accelerates

The ground below our feet and beneath the ocean floor is an electricly-charged grid that bacteria has created by “exhaling” excess electrons from tiny nanowires in an oxygen depleted environment. Yale University researchers are studying how to increase this natural electrical conductivity in nanowires that are 1/100,000.00th the width of human hair.

A new study was published in Science Advances today by Peter Dahl, a graduate student, and Nikhil Malvankar (Assistant Professor of Molecular Biophysics and Biochemistry at the Microbial Sciences Institute), and Victor Batista (Professor of Chemistry). The team found that nanowires can move 10 billion electrons per minute without energy loss. This research shows the incredible ability of these bacteria to transmit electrons over very long distances.

Researchers also discovered that cooling the environment surrounding the bacteria Geobacter from room temperature to freezing increases conductivity by 300-fold. This is surprising, as cooling can freeze electrons and slow them down in organic materials. Combining theory and experiments, the researchers discovered that lower temperatures can restructure hydrogen bonds, flatten heme protein structures, and increase the flow of electricity.

This naturally occurring electrical grid could be leveraged to develop living, self-repairing circuits, new sources and bioremediation strategies. Sophia Yi, Yangqi Gu and Catharine Shipps are also authors.