These are not the only bacteria found to have useful properties. In August 2018, a team of microbiologists from Washington State University found bacteria in Yellowstone National Park’s Heart Lake Geyser basin that could “breathe” electricity by passing electrons to external metals or minerals, using protruding wire-like hairs. As the bacteria exchange electrons, they produce a stream of electricity that could potentially be harnessed for low-power applications. In theory, as long as the bacteria have fuel, they can continuously produce energy. Then, in June 2022, a team of researchers at Binghamton University found a way to power biobatteries for weeks using three types of bacteria placed in separate chambers. These discoveries show that nature can provide many solutions to some of today’s most insurmountable issues. All that is required is a little research and development in the right direction. The findings were first published in the journal Nature Communications.
Study summary:
Light-induced microbial electron transport has the potential for efficient production of value-added chemicals, biofuels, and biodegradable materials due to diversified metabolic pathways. However, most microbes lack photoactive proteins and require synthetic photosensitizers that suffer from photocorrosion, photodegradation, cytotoxicity, and generation of photoexcited radicals that are harmful to cells, thus severely limiting catalytic performance. Therefore, there is a pressing need for biocompatible photoconductive materials for efficient electronic interface between microbes and electrodes. Here we show that living biofilms of Geobacter sulfurreducens use cytochrome OmcS nanowires as intrinsic photoconductors. Photoconductive atomic force microscopy shows up to a 100-fold increase in photocurrent in purified single nanowires. Photocurrents respond rapidly (<100 ms) to stimulation and persist reversibly for hours. Femtosecond transient absorption spectroscopy and quantum dynamics simulations reveal ultrafast (∼200 fs) electron transfer between nanowire hemes upon photoexcitation, enhancing carrier density and mobility. Our work reveals a new class of natural photoconductors for whole cell catalysis.
