Time‐resolved fluorometry of purple membrane of Halobacterium halobium O640 and an O‐like red‐shifted intermediate Q

FEBS Letters

Ohtani, Hiroyuki¹  Itoh, Hiroyasu²  Shinmura, Toshiki¹ 

[1] Department of Biomolecular Engineering, Faculty of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama 227, Japan;Tsukaba Research Laboratory, Hamamatsu Photonics K.K., 5-3-1, Tokodai, Tsukuba, Ibaraki 300-12, Japan

关键词: Bacteriorhodopsin;    Purple membrane;    Photocycle of N560;    Fluorescence of O640;    Q intermediate;    Halobacterium halobium;   

DOI  :  10.1016/0014-5793(92)80643-U

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The photocycle of the light-adapted purple membrane was studied with a time-resolved fluorometry apparatus: fluorescence of the sample suspension (>660 nm) was pumped with a 633-nm cw laser and the temporal change induced by a 532-nm pulsed laser was measured with a photon-counting-type transient recorder. The formation and the decay of the O₆₄₀ intermediate were clearly observed in the pH region between 4.0 and 11.4. A photochemical cycle of N₅₆₀ was apparently driven in alkaline suspension (pH > 9.3). An O-like fluorescent intermediate Q appears and decays with time constants of <0.1 ms and 1.7 ± 0.2 ms, respectively.

【 授权许可】

Unknown