title: Dynamics of primary events in the photocycle of excited bacteriorhodopsin.
abstract: Transient dynamic behavior of the excited bacteriorhodopsin (BR), which was isolated from the strain H. salinarum, was studied at excitation wavelength from 585 to 639 nm. With the one-color femtosecond (fs) pump-probe technique, we revealed the primary events in BR's photocycle that took place in an ultrafast time scale. From the analysis of the decay components of the dynamical traces, it was evident that the isomerization of the retinal chromophore in BR and the intermediate J's formation occurred within 500 fs. BR exhibited pH-dependent dynamical behaviors. When the medium pH was between 5 and 9, the BR ultrafast dynamics has no obvious change. In contrast, the dynamical curves were obviously affected when the pH was out of that region.
authors.affiliation: Department of Physics, Fudan University, Shanghai 200433, China.
authors.forename: Jun-Jun
authors.initials: JJ
authors.lastname: Lu
authors.forename: Ming
authors.initials: M
authors.lastname: Ming
authors.forename: Yi
authors.initials: Y
authors.lastname: Yang
authors.forename: Jia
authors.initials: J
authors.lastname: Wu
authors.forename: Bo
authors.initials: B
authors.lastname: Li
authors.forename: Jian-Dong
authors.initials: JD
authors.lastname: Ding
authors.forename: Qing-Guo
authors.initials: QG
authors.lastname: Li
authors.forename: Shi-Xiong
authors.initials: SX
authors.lastname: Qian
mesh_terms: D001436:Bacteriorhodopsins / Q000737:chemistry*; D055592:Biophysical Phenomena; D001703:Biophysics; D006217:Halobacterium / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007834:Lasers; D008027:Light; D010777:Photochemistry; D011487:Protein Conformation; D012160:Retina / Q000378:metabolism; D013053:Spectrophotometry; D013997:Time Factors
chemical_list: D001436:Bacteriorhodopsins