title: Vibronic coherence in oxygenic photosynthesis.
abstract: Photosynthesis powers life on our planet. The basic photosynthetic architecture consists of antenna complexes that harvest solar energy and reaction centres that convert the energy into stable separated charge. In oxygenic photosynthesis, the initial charge separation occurs in the photosystem II reaction centre, the only known natural enzyme that uses solar energy to split water. Both energy transfer and charge separation in photosynthesis are rapid events with high quantum efficiencies. In recent nonlinear spectroscopic experiments, long-lived coherences have been observed in photosynthetic antenna complexes, and theoretical work suggests that they reflect underlying electronic-vibrational resonances, which may play a functional role in enhancing energy transfer. Here, we report the observation of coherent dynamics persisting on a picosecond timescale at 77 K in the photosystem II reaction centre using two-dimensional electronic spectroscopy. Supporting simulations suggest that the coherences are of a mixed electronic-vibrational (vibronic) nature and may enhance the rate of charge separation in oxygenic photosynthesis.
authors: Department of Physics and Biophysics, University of Michigan, Ann Arbor, Michigan 48109, USA.
authors: Franklin D
authors: FD
authors: Fuller
authors: Department of Physics and Biophysics, University of Michigan, Ann Arbor, Michigan 48109, USA.
authors: Jie
authors: J
authors: Pan
authors: 1] Department of Theoretical Physics, Faculty of Physics of Vilnius University, Sauletekio Avenue 9, 10222 Vilnius, Lithuania [2] Center for Physical Sciences and Technology, Gostauto 9, 01108 Vilnius, Lithuania.
authors: Andrius
authors: A
authors: Gelzinis
authors: 1] Department of Theoretical Physics, Faculty of Physics of Vilnius University, Sauletekio Avenue 9, 10222 Vilnius, Lithuania [2] Center for Physical Sciences and Technology, Gostauto 9, 01108 Vilnius, Lithuania.
authors: Vytautas
authors: 0000000349803034
authors: V
authors: Butkus
authors: Department of Physics and Biophysics, University of Michigan, Ann Arbor, Michigan 48109, USA.
authors: S Seckin
authors: SS
authors: Senlik
authors: Department of Physics and Biophysics, University of Michigan, Ann Arbor, Michigan 48109, USA.
authors: Daniel E
authors: DE
authors: Wilcox
authors: Department of Molecular, Cellular and Developmental Biology and Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA.
authors: Charles F
authors: CF
authors: Yocum
authors: 1] Department of Theoretical Physics, Faculty of Physics of Vilnius University, Sauletekio Avenue 9, 10222 Vilnius, Lithuania [2] Center for Physical Sciences and Technology, Gostauto 9, 01108 Vilnius, Lithuania.
authors: Leonas
authors: L
authors: Valkunas
authors: Department of Theoretical Physics, Faculty of Physics of Vilnius University, Sauletekio Avenue 9, 10222 Vilnius, Lithuania.
authors: Darius
authors: D
authors: Abramavicius
authors: Department of Physics and Biophysics, University of Michigan, Ann Arbor, Michigan 48109, USA.
authors: Jennifer P
authors: JP
authors: Ogilvie
mesh_terms: D056004:Molecular Dynamics Simulation; D010100:Oxygen / Q000737:chemistry; D010788:Photosynthesis; D045332:Photosystem II Protein Complex / Q000737:chemistry / Q000378:metabolism*; D013696:Temperature; D014732:Vibration
chemical_list: D045332:Photosystem II Protein Complex; D010100:Oxygen