Studying a species of rock-dwelling bacteria called Shewanella, scientists have found how it can transform minerals by zapping them with tiny electrical currents. This could be the discovery of the century, as it could lead to the production of a new type of fuel cells that will generate electricity. Fuel cells will help different industries pollute less which is the most important thing for us at the moment but as well, the bacteria can help to create a new generation of organically made materials.
Bacteria can be found everywhere in nature as they have an excellent adaptability for every environment. As they can live in the absence of oxygen, scientists were puzzled for nearly half a century. Even when they found out that the micro-organisms are using rocks to generate electrons, they still couldn’t figure out how this was possible.
But after 5 years of laboratory studies in the U.S. and the UK, a team of scientists has elucidated the mystery. Shewanella has a protein on its surface that works like an electrical wire between the interior and exterior of the bacteria. The protein is called deca-heme c-class cytochromes and can bond to the surface molecules of the rock allowing in this way the transfer of electrons through the membrane. This process also releases chemical elements as iron and manganese, altering the rock.
One of the geo-chemists working on this project, Susan Brantley from the Pennsylvania State University, said that Shewanella is the key to using such bacteria in cheap electricity production but also in oil-spill cleanup.
Bio-chemist David Richardson of the University of East Anglia in the United Kingdom said that Shewanella is the ideal candidate for environmental-cleanup tasks as it lives in the underground: “Understanding their biochemistry could help to develop strategies to stimulate their activities [at the cleanup sites].”
Laboratory tests have shown that other types of bacteria are also able to generate electricity making the discovery far more important.
