Organization of Plant Photosystem II and Photosystem I Supercomplexes
In nature, plants are continuously exposed to varying environmental conditions. They have developed a wide range of adaptive mechanisms, which ensure their survival and maintenance of stable photosynthetic performance. Photosynthesis is delicately regulated at the level of the thylakoid membrane of chloroplasts and the regulatory mechanisms include a reversible formation of a large variety of specific protein-protein complexes, supercomplexes or even larger assemblies known as megacomplexes. Revealing their structures is crucial for better understanding of their function and relevance in photosynthesis. Here we focus our attention on the isolation and a structural characterization of various large protein supercomplexes and megacomplexes, which involve Photosystem II and Photosystem I, the key constituents of photosynthetic apparatus. The photosystems are often attached to other protein complexes in thylakoid membranes such as light harvesting complexes, cytochrome b 6 f complex, and NAD(P)H dehydrogenase. Structural models of individual supercomplexes and megacomplexes provide essential details of their architecture, which allow us to discuss their function as well as physiological significance.
KeywordsPhotosystem I Photosystem II Clear native gel electrophoresis Electron microscopy Supercomplex Megacomplex
This work was supported by the grant project LO1204 (Sustainable development of research in the Centre of the Region Haná) from the National Program of Sustainability I from the Ministry of Education, Youth and Sports, Czech Republic. Dr. Roman Kouřil was supported by a Marie Curie Career Integration Grant call FP7-PEOPLE-2012-CIG (322139). We acknowledge funding by the European Union’s Horizon 2020 research and innovation programme under grant agreement no. 675006.
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