Conformational regulation of charge recombination reactions in a photosynthetic bacterial reaction center.
In bright light the photosynthetic reaction center (RC) of Rhodobacter sphaeroides stabilizes the P(+)(870).Q(-)(A) charge-separated state and thereby minimizes the potentially harmful effects of light saturation. Using X-ray diffraction we report a conformational change that occurs within the cytoplasmic domain of this RC in response to prolonged illumination with bright light. Our observations suggest a novel structural mechanism for the regulation of electron transfer reactions in photosynthesis.
Katona
Gergely
G
Chalmers University of Technology, Department of Chemistry and Bioscience, PO Box 462, SE-405 30 Göteborg, Sweden.
Snijder
Arjan
A
Gourdon
Pontus
P
Andréasson
Ulf
U
Hansson
Orjan
O
Andréasson
Lars-Erik
LE
Neutze
Richard
R
D003461:Crystallography; D004579:Electron Transport / Q000502:physiology; D008027:Light; D008958:Models, Molecular; D010777:Photochemistry; D045322:Photosynthetic Reaction Center Complex Proteins / Q000737:chemistry* / Q000378:metabolism; D011487:Protein Conformation; D012242:Rhodobacter sphaeroides / Q000378:metabolism*; D014961:X-Ray Diffraction
D045322:Photosynthetic Reaction Center Complex Proteins