Coupled-protein functionality for energy conversion in biomimetic systems

In nature, proteins commonly function as energy transducing machinery, converting solar energy to chemical or electrical energy. In its natural forward reaction, cytochrome c oxidase accepts an electron from cytochrome c to form water from the translocation of protons to combine with oxygen. We have shown that by coupling cytochrome c oxidase with bacteriorhodopsin, a light-dependent proton pump, in a biomimetic triblock copolymer membrane, we can partially reverse cytochrome c oxidase activity to serve as an electron donor to oxidized cytochrome c. We have demonstrated nanoampere-range current switching in response to exposure to light