UC Berkeley

Natural photosynthetic light harvesting systems maintain precise control over the energetics, positions and relative orientations of densely packed arrays of chromophores. This dissertation describes the efforts to achieve similar structural control in synthetic analogues and to understand the structure-function interplays using the artificial systems. Based on the central scaffold, the double-disk assembly of the tobacco mosaic virus (TMV) capsid proteins, a series of protein-pigments conjugates were designed, constructed, and characterized. The mobility and orientation of the chromophores were carefully controlled combining linker engineering with the protein confinement. A systematic study was done to understand how the fine-tuning of these structural elements could affect the chromophore photophysics. The utility of the TMV scaffolds was further expanded by the introduction of unnatural binding sites to create protein-embedded metal porphyrin arrays. Finally, the use of a dimeric TMV coat protein to create higher-order membrane-attached light harvesting networks was explored.