Coherence dynamics in photosynthesis: protein protection of excitonic coherence.
The role of quantum coherence in promoting the efficiency of the initial stages of photosynthesis is an open and intriguing question. We performed a two-color photon echo experiment on a bacterial reaction center that enabled direct visualization of the coherence dynamics in the reaction center. The data revealed long-lasting coherence between two electronic states that are formed by mixing of the bacteriopheophytin and accessory bacteriochlorophyll excited states. This coherence can only be explained by strong correlation between the protein-induced fluctuations in the transition energy of neighboring chromophores. Our results suggest that correlated protein environments preserve electronic coherence in photosynthetic complexes and allow the excitation to move coherently in space, enabling highly efficient energy harvesting and trapping in photosynthesis.
Lee
Hohjai
H
Department of Chemistry and QB3 Institute, University of California, Berkeley, USA.
Cheng
Yuan-Chung
YC
Fleming
Graham R
GR
D001429:Bacteriochlorophylls / Q000737:chemistry / Q000378:metabolism*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D004735:Energy Transfer; D007834:Lasers; D008433:Mathematics; D009038:Motion; D010674:Pheophytins / Q000737:chemistry / Q000378:metabolism*; D017785:Photons; D010788:Photosynthesis; D045322:Photosynthetic Reaction Center Complex Proteins / Q000737:chemistry / Q000378:metabolism*; D012242:Rhodobacter sphaeroides / Q000737:chemistry / Q000378:metabolism*; D013997:Time Factors
D001429:Bacteriochlorophylls; D010674:Pheophytins; D045322:Photosynthetic Reaction Center Complex Proteins; C006678:bacteriopheophytin