Protonation changes during the photocycle of sensory rhodopsin II from Natronobacterium pharaonis

FEBS Letters

Siebert, F¹  Scharf, B²  Engelhard, M² 

[1] Institut für Biophysik und Strahlenbiologie der Universität, Albertstr. 23, 79104 Freiburg, Germany;Max-Planck-Institut für Molekule Physiologie, Rheinlanddamm 201, 44139 Dortmund, Germany

关键词: Fourier Transform Infrared (FTIR) spectroscopy;    Phoborhodopsin;    Sensory rhodopsin;    Phototaxis;    Signal transduction;    BR;    bacteriorhodopsin;    FTIR;    Fourier transform infrared spectroscopy;    HR;    halorhodopsin;    SR;    sensory rhodopsin;   

DOI  :  10.1016/0014-5793(96)01041-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The Fourier Transform Infrared (FTIR) spectra of photocycle intermediates of sensory rhodopsin II (pSRII) from Natronobacterium pharaonis were measured. The results of the FTIR experiments indicate considerable conformational movements of pSRII already at the stage of the early K-like intermediate which persist at least during the lifetime of the long lived intermediate. These changes in the amide bond region are more intense than those described for sensory rhodopsin I (SRI) and are quite similar to those observed for rhodopsin. Concomitantly with the deprotonation of the Schiff base a carboxyl group located in a hydrophobic environment is protonated. In analogy to bacteriorhodopsin, this carboxyl group might arise from Asp-75 which probably serves as counter ion to the Schiff base. The protonation reaction differs from the situation observed in SRI where the protonation is pH independent over the range of pH 5–8.

【 授权许可】

Unknown