STRUCTURE AND DYNAMICS OF BACTERIORHODOPSIN - COMPARISON OF SIMULATION AND EXPERIMENT

Global features of the structure and dynamics of bacteriorhodopsin are investigated using molecular modelling, dynamical simulations and neu tron scattering experiments. The simulations are performed on a model system consisting of one protein molecule plus intrinsic water molecul es. The simulation-derived structure is compared with neutron diffract ion data on the location of water and with the available electron micr oscopy structure of highest resolution. The simulated water geometry i s in good accord with the neutron data. The protein structure deviates slightly but significantly from the experiment. The low-frequency vib rational frequency distribution of a low-hydration purple membrane is derived from inelastic neutron scattering data and compared with the c orresponding simulation-derived quantity.