Recent advances in understanding the assembly and repair of photosystem II

摘要: Background Photosystem II (PSII) is the light-driven water:plastoquinone oxidoreductase of oxygenic photosynthesis and found in thylakoid membrane chloroplasts cyanobacteria. Considerable attention focused on how PSII assembled vivo it repaired following irreversible damage by visible light (so-called photoinhibition). Understanding these processes might lead to development plants with improved growth characteristics especially under conditions abiotic stress. Scope Here we summarize recent results assembly repair cyanobacteria, which are excellent model organisms study higher plant photosynthesis. Conclusions Assembly highly co-ordinated proceeds through a number distinct intermediates. Associated complexes proteins that not final functional complex. Structural information possible functions beginning emerge for several 'assembly' factors, notably Ycf48/Hcf136, Psb27 Psb28. A other auxiliary have been identified appear evolved since divergence The involves partial disassembly damaged complex, selective replacement sub-unit (predominantly D1 sub-unit) newly synthesized copy, reassembly. It likely chlorophyll released during process temporarily stored small CAB-like (SCPs). proposed removed Synechocystis sp. PCC 6803 hetero-oligomeric complex composed two different types FtsH (FtsH2 FtsH3), degradation proceeding from N-terminus processive reaction. postulated similar mechanism also operates chloroplasts. Deg proteases required but members this protease family play supplementary role extreme conditions.