In our laboratory, we have developed mediatorless direct photosynthetic/metabolic bio fuel cell (DPMFC). This battery's principle is that microparticles of Polyaniline were adopted as electrodes to draw electrons directly from bacteria, and the output is fundamentally decided by the electron emission efficiency of bacteria. The present paper aims to improve this by applying Gene Manipulation Technology. We adopted purple photosynthetic bacteria (PPBs) because they have special characteristics such as being activated by organic compounds as well as emitting hydrogen in photosynthetic and metabolic processes. We improved the electron generation efficiency of the bacteria by applying gene manipulation technology to inhibit hydrogen emission. Our hypothesis is that more electrons will be stored inside the bacteria if hydrogen emission is inhibited. As a result, the power density of Gene manipulated bacteria became 10μW/cm^2, that is higher than the normal one.
