Producing Electricity is one of the great challenges of the modern world and We have been producing electricity by burning coal, using nuclear fission, Solar power, Wind Power etc etc for decades. However each of these have some drawback or other, and they are all not very portable. To power our portable devices & sensors we use batteries that are a big ecological issue as despite decades of effort most synthetic and molecular electronic materials remain bio-incompatible and nonbiodegradable. Plus the batteries only last for a limited time before needing to be replaced. Solar cells are good but don’t work at night plus we still need to store the power generated which brings us back to the battery problem.
Due to the above mentioned issues, we have been searching for new and improved ways to produce electricity that reduce the ecological impact of power generation. One of the ways explored is to use Microbial fuel cells powered by Bacteria, specifically Geobacter Colonies. Geobacter is a groundwater-dwelling genus of bacteria that lives in the soil beneath our feet and has the fascinating capability of producing electrons as waste much like how we humans generate CO2 while breathing. These electrons are then transmitted through what is essentially a giant snorkel of nanowire made out of a conductive material into the soil around the bacteria. In previous research, Nikhil Malvankar, an assistant professor at Yale University’s Microbial Science Institute in Connecticut and his colleagues found that when the Geobacter microbes are exposed to a small electrode in the lab they automatically assemble into interlinked piles of hundreds of individual microbes, capable of moving electrons through a single shared network. This substantially increases the amount of electricity produced by the microbes.
Now the question they had to answer was that how are the microbes able to transmit electrons through the interlinked piles efficiently so they set about using cutting-edge microscopy techniques to study the phenomenon. The first technique, called high-resolution atomic force microscopy, gathered information about the structure of the nanowires by touching their surface with an extremely sensitive mechanical probe and the second technique, called infrared nanospectroscopy used infrared light which was reflected off the nonowires to identify specific molecules. With these two methods, the researchers saw the “unique fingerprint” of each amino acid in the proteins that make up Geobacter’s nanowires.
During the study the team found that, when stimulated by an electric field Geobacter produced a previously unknown kind of nanowire made of a protein called OmcZ which is made of tiny, metallic building blocks called hemes. This new type of nanowire is over a 1,000 times more efficient in conducting electricity than the normal one. This new research has been published on Aug. 17 in the journal Nature Chemical Biology and it has paved the way to making the production of bio-electronics both cheaper and easier by increasing the power generated by the bacterial colony.
Once we figure out how to replicate this at scale then we will have the ability to generate sustainable power using just the microbes from beneath our feet.
Source: Scientists find ‘secret molecule’ that allows bacteria to exhale electricity
– Suramya