Structure of the retinal chromophore in halorhodopsin

FEBS Letters

Hegemann, P.²  Oesterhelt, D.²  Alshuth, T.¹  Stockburger, M.¹ 

[1] Max-Planck-Institut für Biophysikalische Chemie, 3400 Göttingen, 8033 Martinsried, FRG;Max-Planck-Institut für Biochemie, 8033 Martinsried, FRG

关键词: Halorhodopsin;    Light-driven chloride pump;    Resonance Raman spectroscopy;    Protonated Schiff base;   

DOI  :  10.1016/0014-5793(85)80190-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Resonance Raman (RR) spectra of the light-driven chloride pump halorhodopsin (HR) were recorded after isolation of the protein from cell membranes of Halobacterium halobium. The spectra of the unphotolyzed state HR₅₇₈ were compared with those of two unphotolyzed species of the light-driven proton pump bacteriorhodopsin, BR₅₇₀ and BR₅₄₈, which were obtained from light- and dark-adapted purple membranes. Identical structural components in the retinal chromophores of HR₅₇₈ and BR₅₇₀ are found, both having the all-trans configuration of the retinal chain and a protonated Schiff base linkage to the protein with anti-position of the two hydrogens. Only minor conformational differences between the chromophoric structures in the two proteins could be inferred from the vibrational structure of the RR spectra. The function of the two chromophores as triggers of light-induced chloride or proton transport emphasizes the role of the protein part in the ion specificity of the pumps.

【 授权许可】

Unknown