title: Femtosecond infrared spectroscopy of channelrhodopsin-1 chromophore isomerization.
abstract: Vibrational dynamics of the retinal all-trans to 13-cis photoisomerization in channelrhodopsin-1 from Chlamydomonas augustae (CaChR1) was investigated by femtosecond visible pump mid-IR probe spectroscopy. After photoexcitation, the transient infrared absorption of C-C stretching modes was detected. The formation of the 13-cis photoproduct marker band at 1193 cm(-1) was observed within the time resolution of 0.3 ps. We estimated the photoisomerization yield to (60 ± 6) %. We found additional time constants of (0.55 ± 0.05) ps and (6 ± 1) ps, assigned to cooling, and cooling processes with a back-reaction pathway. An additional bleaching band demonstrates the ground-state heterogeneity of retinal.
authors.affiliation: Department of Physics, Institute of Experimental Physics , Freie Universität Berlin , Arnimallee 14, 14195 Berlin, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Stensitzki
authors.affiliation: Department of Physics, Institute of Experimental Physics , Freie Universität Berlin , Arnimallee 14, 14195 Berlin, Germany.
authors.forename: Y
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Genetic Biophysics, Department of Physics, Freie Universität Berlin , Arnimallee 14, 14195 Berlin, Germany.
authors.forename: V
authors.initials: V
authors.lastname: Muders
authors.affiliation: Genetic Biophysics, Department of Physics, Freie Universität Berlin , Arnimallee 14, 14195 Berlin, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Schlesinger
authors.affiliation: Experimental Molecular Biophysics, Department of Physics, Freie Universität Berlin , Arnimallee 14, 14195 Berlin, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Heberle
authors.affiliation: Department of Physics, Institute of Experimental Physics , Freie Universität Berlin , Arnimallee 14, 14195 Berlin, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Heyne