New and unexpected routes for ultrafast electron transfer in photosynthetic reaction centers.
In photosynthetic reaction centers, the excitation with light leads to the formation of a charge separated state across the photosynthetic membrane. For the reaction center of purple non-sulphur bacteria, it was previously generally assumed that this primary charge separation could only start with the excitation of the so-called special pair of bacteriochlorophyll molecules located in the heart of the RC. However, recently new and ultrafast pathways of charge separation have been discovered in the bacterial RC that are driven directly by the excited state of the accessory monomeric bacteriochlorophyll present in the active branch of cofactors. These results demonstrate that the route for energy conversion in photosynthesis can be much more flexible than previously thought. We suggest that the existence of multiple charge separation routes is particularly relevant for the mechanism of charge separation in the photosystem II reaction center of higher plants.
van Brederode
M E
ME
Department of Biophysics and Physics of Complex Systems, Vrije Universiteit and Institute of Molecular Biological Sciences (IMBW), Vrije Universiteit, Amsterdam, The Netherlands.
van Grondelle
R
R
D004579:Electron Transport; D045342:Light-Harvesting Protein Complexes; D045322:Photosynthetic Reaction Center Complex Proteins / Q000378:metabolism*; D045332:Photosystem II Protein Complex
D045342:Light-Harvesting Protein Complexes; D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex