Dissipation of excess energy triggered by blue light in cyanobacteria with CP43' (isiA).
The chlorophyll-protein CP43' (isiA gene) induced by stress conditions in cyanobacteria is shown to serve as an antenna for Photosystem II (PSII), in addition to its known role as an antenna for Photosystem I (PSI). At high light intensity, this antenna is converted to an efficient trap for chlorophyll excitations that protects system II from photo-inhibition. In contrast to the 'energy-dependent non-photochemical quenching' (NPQ) in chloroplasts, this photoprotective energy dissipation in cyanobacteria is triggered by blue light. The induction is proportional to light intensity. Induction and decay of the quenching exhibit the same large temperature-dependence.
Cadoret
Jean-Charles
JC
Organismes Photosynthétiques et Environnement, FRE 2433 CNRS, Département de Biologie, ENS, 46 rue d'Ulm, 75230 Paris cedex 05, France.
Demoulière
Raphaël
R
Lavaud
Johann
J
van Gorkom
Hans J
HJ
Houmard
Jean
J
Etienne
Anne-Lise
AL
D000222:Adaptation, Physiological / Q000502:physiology / Q000528:radiation effects; D001426:Bacterial Proteins / Q000378:metabolism*; D002478:Cells, Cultured; D004307:Dose-Response Relationship, Radiation; D004735:Energy Transfer / Q000502:physiology* / Q000528:radiation effects*; D000090463:Iron Deficiencies; D008027:Light; D045342:Light-Harvesting Protein Complexes / Q000378:metabolism*; D045332:Photosystem II Protein Complex / Q000378:metabolism* / Q000528:radiation effects*; D046939:Synechocystis / Q000502:physiology* / Q000528:radiation effects*; D013696:Temperature
D001426:Bacterial Proteins; D045342:Light-Harvesting Protein Complexes; D045332:Photosystem II Protein Complex; C076726:chlorophyll A binding protein CP43, Cyanobacteria