Kris Niyogi studies photosynthetic energy conversion and its regulation in algae and plants.
Biogenesis and Assembly of Photosynthetic Membrane Complexes
Photosynthesis is the biological process that converts solar energy and carbon dioxide into biomass, from which we derive food and fuel. Photosystem II (PSII) is the pigment-protein complex in photosynthetic membranes that uses light energy to oxidize water and produce high-energy electrons. Although high-resolution structures are now available for PSII, a thorough understanding of how the pigments, protein subunits, and cofactors are assembled into functional complexes is lacking. To identify novel factors that are necessary for PSII assembly, we are characterizing mutants of the model photosynthetic eukaryote, Chlamydomonas reinhardtii, that lack PSII. Genetic analysis of the mutants will involve crosses to determine the underlying genetic basis for the phenotype and identification of the defective gene by PCR-based approaches and DNA sequencing. Membrane protein composition will be investigated by SDS-PAGE, blue-native PAGE, and immunoblotting, and the architecture of the photosynthetic membrane will be imaged by electron microscopy and atomic force microscopy.