Bacteria for Bio-batteries

http://toi.in/mKofFY

06 Jul 2013

In a constantly advancing world, the growth of industry has brought about an overuse of non-renewable energy sources and the improper disposal of by-products which have grossly, although sometimes unavoidably, polluted the planet.  This has led to the constant search for green sources of energy as these sources in themselves will help preserve the world’s limited natural resources, and will most likely have a significantly lower carbon footprint. Such a development can exponentially benefit the environment and the population by reducing the levels of greenhouse gases and harmful by-products while providing the energy needed.  Fortunately, this goal is gradually becoming a reality with the latest breakthrough in the study of bio-batteries.

Bio-batteries are basically batteries powered by organic compounds, which by loose definition are most carbon-containing compounds. As early as 2003, research has already been ongoing for the development of bio-batteries as an alternative, clean and green source of energy. Over the last decade, progress has been made in this field of study with the development by different companies and research groups of several successful prototype forms of bio-batteries, such as glucose-powered devices, living tissue-powered devices and more [howstuffworks.com]. Last March 28, 2013, however, British scientists and researchers from the University of East Anglia made the latest major breakthrough in the study of bio-batteries whilst in the pursuit to generate electricity from bacteria [TNN].

In the latest findings published by the British research team, it was reported that bacteria are able to produce electricity and conduct this electricity through their cell membranes via proteins upon surface contact with a metal or mineral. This discovery is considered to be one of great significance because of its implications.  This new knowledge suggests that it is possible to directly tether the bacteria to electrodes through which the electrical charge produced by the bacteria will flow and be transferred to another object or substance [TNN]. According to lead researcher Dr. Tom Clarke, the fact that bacteria could produce and transfer electrical currents to minerals was already known to the scientists. However, the actual means by which the electrical current was transferred was unclear [TNN].

In an attempt to determine this missing piece of information, the researchers developed a synthetic form of the marine bacteria Shewanella Oneidensis by inserting the presumed conductor proteins into the capsules of lipid membranes to mimic bacterial membrane.  Using this synthetic bacterium, they were able to test the flow of electrons between the internal source and an external iron-bearing mineral [TNN]. 
From these tests, it was finally concluded that specific proteins on the bacteria’s surface can directly contact a mineral’s surface and transfer the electricity without the need for any external mediator [TNN].
The discovery shows that bacteria are a potentially great source of clean energy, and brings scientists ever closer to producing viable and efficient bio-batteries [TNN]. Consequently, this latest breakthrough is very promising for the future of renewable and clean energy sources.