The high light-inducible polypeptides in Synechocystis PCC6803. Expression and function in high light.

摘要: There are five Synechocystis PCC6803 genes encoding polypeptides with similarity to the Lhc of plants. Four polypeptides, designated HliA-D (Dolganov, N. A. M., Bhaya, D., and Grossman, R. (1995) Proc. Natl. Acad. Sci. U. S. 92, 636-640) (corresponding ScpC, ScpD, ScpB, ScpE in Funk, C., Vermaas, W. (1999) Biochemistry 38, 9397-9404) contain a single transmembrane domain. The fifth polypeptide (HemH) represents fusion between ferrochelatase an Hli-like polypeptide. By using epitope tag identify specifically different Hli accumulation each (excluding HemH) was examined under various environmental conditions. levels all were elevated high light during nitrogen limitation, whereas HliA, HliB, HliC also accumulated following exposure sulfur deprivation low temperature. temporal pattern significantly among polypeptides. rapidly light, its level remained for at least 24 h. HliA HliB rapidly, but their began decline 9-12 h imposition light. HliD transiently expressed not detected after initiation exposure. These results demonstrate that there is specificity diverse range Furthermore, mutants individual combinations hli evaluated fitness grow Although grew as fast wild-type cells strains inactivated hliA or hliC/hliD unable compete co-cultivation A mutant lacking four gradually lost photosynthesis capacity died Hence, critical survival when absorbing excess excitation energy may allow cope more effectively production reactive oxygen species.