With this award the PI will employ two-dimensional electronic spectroscopy (2DES) to investigate the underlying physical mechanisms governing the directional ultrafast transfer of energy between the antennae and reaction centers of photosynthetic purple bacteria. The program of research will both push the capabilities of 2DES as a powerful and quantitative method for studying natural photosynthetic systems, and use 2DES to address open questions about photosynthesis in purple bacteria. Specifically, this research aims to answer the following questions: 1) What are the roles of vibrational and electronic coherence in energy transfer and charge separation in purple bacteria? 2) How do purple bacteria remodel their energy-landscape to regulate energy transfer under high and low light conditions? This research aims to extend the capabilities of 2DES spectroscopy to perform the first 2DES experiments on single crystals of photosynthetic complexes as well as the first 2DES experiments on whole cells. Improvements in the capabilities of 2DES, and its ability to provide feedback to theoretical modeling of energy transfer and charge separation in purple bacteria as a model system will ultimately pave the way for a better understanding of the more complex plant photosystems. Understanding the role of coherence in photosynthetic energy transfer and charge separation may drive the development of new theoretical models of these processes. The award also aims to promote a positive image of science through public education, and in particular to encourage women and minorities to enter careers in science through outreach activities and mentored undergraduate research.
This project is being jointly supported by the Physics of Living Systems program in the Division of Physics and the Molecular Biophysics Program in the Division of Molecular and Cellular Biosciences.
