The photosynthetic reaction center is a remarkable machine that absorbs light and transfers electrons across a biological membrane. Membranes are very thin insulators so this process is similar to charging a capacitor. Once charged, the capacitor discharges by driving the biosynthesis of stable energetic molecules or fuels. All life on earth depends on this process. This research program will continue to support the development of a generation of young scientists with diverse backgrounds, primarily graduate students, who go on to productive careers at the interface of the physical sciences and biology, biotechnology, and energy-related science. In addition to scientific publications, the results of this work are presented in many invited talks that reach out to diverse communities from the high-school level to government agencies looking to future directions in nanoscience, biotechnology and energy-related science. Photosynthesis is a topic of deep interest to a wide community of scientists and engineers as well as to the general public. This work provides the basis for the development of new courses both for college freshman and graduating seniors stressing the importance of critical reading using current frontiers and controversies in biophysics firmly grounded in the physical sciences.
The objectives of this research are to better understand the mechanisms by which photosynthetic reaction centers harvest and store solar energy, and to develop model membrane assemblies that mimic natural biological membranes and their interactions. This research will focus on understanding how the organized environment in proteins modulates the spectroscopic and redox properties of bound prosthetic groups like chlorophylls and quinones and on the mechanism of the initial light-driven reactions. A significant part of this work involves the development of new experimental and theoretical methods that will have a broad impact in other areas of science and technology. Stimulated by studies of this important integral membrane protein, novel membrane assemblies will be developed to create defined architectures for the organization of any membrane protein. Membrane proteins serve as gatekeepers for the otherwise impervious membranes that surround cells and internal organelles. They are also the primary contact between cells. These proteins are difficult to work with and characterize in their native environment, and this research will create new ways to study their function by designing architectures that are compatible with sophisticated optical and electrical detection methods. Thus, the two objectives are deeply connected as different aspects of membrane biophysics.
