2016/07/06 by Sarah E. Morgan, Morgan, Sarah E, Daniel J. Cole +3
Physics and Astronomy · Biochemistry, Genetics and Molecular Biology · Chemistry · #Spectroscopy and Quantum Chemical Studies #Photosynthetic Processes and Mechanisms #Molecular spectroscopy and chirality
paper · pdf · doi:10.48550/arxiv.1607.01651
Collective protein modes are expected to be important for facilitating energy\ntransfer in the Fenna-Matthews-Olson (FMO) complex, however to date little work\nhas focussed on the microscopic details of these vibrations. The nonlinear\nnetwork model (NNM) provides a computationally inexpensive approach to studying\nvibrational modes at the microscopic level, whilst incorporating anharmonicity\nin the inter-residue interactions which can influence protein dynamics. We\napply the NNM to the FMO complex and find evidence for the existence of\nnonlinear discrete breather modes. These modes tend to transfer energy to the\nhighly connected core pigments, potentially opening up alternative excitation\nenergy transfer routes. Incorporating localised modes based on these discrete\nbreathers in the optical spectra calculations for FMO using ab initio site\nenergies and excitonic couplings can substantially improve their agreement with\nexperimental results.\n