| Project Detail |
Cable bacteria are centimetre-long, filamentous, multicellular bacteria present ubiquitously in freshwater and marine sediments, and participate in long-distance electron transfer by coupling the oxidation of sulphide in anoxic sediment to the reduction of oxygen. Cable bacteria possess an internal electric grid, enabling them to transport electrons over centimeter-scale distances. This project proposes the cultivation of cable bacteria on electrodes to harness their potential to generate electricity. Further, the development of a switchable bioelectrochemical system altering between electrogenesis and electrotrophy is proposed. Such a device would enable biological power generation and energy storage in a single device, and will be tested to power a microprocessor biologically, enabling development of biodegradable electronics. These experiments would be performed in specialized bioelectrochemical systems by varying the applied potential from positive to negative to induce the switch. Electrochemical interactions of cable bacteria with electrodes will be monitored by amperometry, voltammetry, and impedance spectroscopy. The cables will be integrated into a power management system consisting of a microprocessor chip, a current and voltage-measuring circuitry and a microcontroller to power the microprocessor with electrons obtained from the sediment. Finally, the physiological possibility of dark oxygen generation by cable bacteria in anaerobic sediments will also be explored, that would enable the use of cables as intermediates to convert any aerobic microbe into an electrogen. This mechanism will potentially uncover an unknown mode of oxygen production and usher in a completely new understanding of oxygen transport through the oxic-anoxic interface. The project bridges the applied and fundamental by probing cable bacteria electrophysiology to develop robust applications that will enable sustainable power generation. |
