Multiscale Modeling of Pigment-Protein Assemblies: Implications for Efficient Solar Energy Harvesting
Date of Award
Doctor of Philosophy (PhD)
Beginning with a review of the photosynthetic energy capture and energy transfer mechanisms of green sulfur bacteria in the context of efficient solar energy harvesting, limitations in the current understanding of these complexes are identified in the first chapter. Specifically, the lack of a complete structural model for light harvesting in green sulfur bacteria at the atomic scale prevents a thorough understanding of energy transfer and forms the basis for questions which comprise the main effort of the dissertation, the solution of which necessitates the use of a multiscale computational approach described in the second chapter. Because individual aspects of these systems such as small-scale protein-ligand interactions require different treatments than larger-scale protein-protein interactions, each component of the extensive multiscale computational methodology is introduced with an emphasis on the information gained as well as the relevant length and timescales. The resulting interactions between photosynthetic pigments and proteins in the model system Chlorobaculum tepidum (formerly Chlorobium tepidum)—including predicted binding motifs for Bacteriochlorophyll a (BChl a) to the chlorosome protein a (CsmA protein), for the CsmA protein to itself to form a dimer, and for the CsmA protein to the Fenna-Matthew-Olson (FMO) protein—are each presented, quantified, and explained in the middle chapters. Finally, implications for future computational studies and closing thoughts are discussed in the final chapter.
Dewey Holten, Jay Ponder, Yinjie Tang