Strain specific differences in rates of Photosystem II repair in picocyanobacteria correlate to differences in FtsH protein levels and isoform expression patterns.

摘要: Picocyanobacteria are the numerically dominant photoautotrophs of oligotrophic regions Earth’s oceans. These organisms characterized by their small size and highly reduced genomes. Strains partition to different light intensity nutrient level niches, with differing photosynthetic apparatus stoichiometry, harvesting machinery susceptibility photoinactivation. In this study, we grew three strains picocyanobacteria: low light, high strain Prochlorococcus marinus MIT 9313; MED 4; marine Synechococcus WH 8102; under growth levels. We then performed matched photophysiology, protein transcript analyses. The differ significantly in rates Photosystem II repair capacity remove PsbA as first step process. Notably, all PsbD subunit at same rate that they PsbA. When grown 9313 loses active quickly when shifted but has no measurable 4 8102 show less rapid loss considerable FtsH protease thought be responsible for removal other cyanobacteria. Furthermore, analysis predominant isoform expressed is homologous model Synechocystis PCC 6803, rather than 2 3 isoforms degradation. on hand shows inducible expression 3, consistent its faster removal. adapted environment diverting resources away from content repair.