Decentralized plug and play systems for energy production are the future picture of our society. Artificial photosynthetic systems are used for this purpose. These systems are inspired by natural... Show moreDecentralized plug and play systems for energy production are the future picture of our society. Artificial photosynthetic systems are used for this purpose. These systems are inspired by natural photosynthesis.Chapter 2 illustrates the detailed construction of a three-flash flow cell to study light induced biological reactions, specifically the water oxidation reaction of Photosystem II. This instrument is capable of producing the S2+, S3+ and S0n intermediate states of the Kok cycle. I confirmed these by EPR experiments.In chapter 3, I study the mechanism of the major LHC II involved in conformational switching from light harvesting to the photoprotective state, in which excess light is dissipated as heat. I use MAS NMR as a non-invasive method to understand the structure and environment around Arg residues in Chlamydomonas reinhardtii LHC II. In this approach the Arg amino acid is selectively labeled with 13C isotopesChapter 4 studies the structure of self-aggregated semi synthetic Zn 31 amino chlorin that forms syn-anti parallel stacks according to the solid state NMR data. The small change of removing 33 methyl group of Zn 31 aminomethyl chlorin has significant effect on self-assembly. Finally, chapter 5 provides an outlook on future research. Show less
Photosynthesis is the process through which plants and photosynthetic organisms convert solar energy into chemical energy. The fundamental primary reaction of photosynthesis is charge separation... Show morePhotosynthesis is the process through which plants and photosynthetic organisms convert solar energy into chemical energy. The fundamental primary reaction of photosynthesis is charge separation which takes place in the photosynthetic reaction centers. Among all photosynthetic reaction centers, the oxidized electron donor of photosystem II is the strongest oxidizing agent known in living nature, based on this capability, water splitting and production of atmospheric oxygen is possible. Despite decades of research, the origin of this oxidizing power is not yet fully understood. Photo-CIDNP (Photochemically induced dynamic nuclear Polarization) MAS (Magic-angle spinning) NMR proves to be a valuable technique to gain information on the primary step of photosynthesis. The work revealed advantages of the technique in the area of solid-state NMR, such as faster scanning and spectral editing by applying it to various types of photosynthetic reaction centers. In addition, studies on isotope labeled photosystems from spinach enabled to generate a model for the donor of photosystem II addressing the origin of the high redox potential. Show less
