Team:Wash U

Our goal for this project is to increase photosynthetic efficiency in the purple bacterium Rhodobacter Sphaeroides by altering the regulation of the light harvesting antenna LH2.  This antenna complex surrounds and harvests photons for the reaction center, where light energy is converted to chemical energy.  We plan to utilize a synthetic light sensing system that will result in an output of a low number of LH2 complexes at high light intensities and a greater number of LH2 complexes at low light intensities.  This project is intended to serve as a proof in principle that light harvesting antenna sizes may be synthetically and dynamically tailored to incidental light intensity in order to increase photosynthetic efficiency in a bioreactor.<br>As much of the world turns to alternative energy in the form of biofuels, photosynthetic efficiency becomes immensely important.  And while individual cells have become very efficient over time due to evolution, large cell cultures perform poorly in bioreactors.  This is because cells near the light source absorb as much light as possible, more than they can convert to chemical energy, leaving cells behind them with almost no light.  Finding a way to limit the amount of light each cell can absorb (below the cell's saturation point) would greatly increase the efficiency of the culture as a whole and enable more biofuels to be produced per reactor.  To learn more about our project, please click [https://2009.igem.org/Team:Wash_U/Project here].