Chang C H, Govindjee R, Ebrey T, Bagley K A, Dollinger G, Eisenstein L, Marque J, Roder H, Vittitow J, Fang J M
Biophys J. 1985 Apr;47(4):509-12. doi: 10.1016/S0006-3495(85)83944-8.
We studied an analogue of bacteriorhodopsin whose chromophore is based on all-trans retinal. A five-membered ring was built around the 13-14 double bond so as to prohibit trans to 13-cis isomerization. No light-induced photochemical changes were seen, other than those due to a small amount (approximately 5%) of unbleached bacteriorhodopsin remaining in the apomembrane used for regeneration. The techniques used included flash photolysis at room and liquid nitrogen temperatures and Fourier-transform infrared difference spectroscopy. When the trans-fixed pigment was incorporated into phospholipid vesicles, no evidence of light-initiated proton pumping could be found. The results indicate that trans to 13-cis isomerization is essential for the photochemical transformation and function of bacteriorhodopsin.
我们研究了一种细菌视紫红质类似物,其发色团基于全反式视黄醛。在13-14双键周围构建了一个五元环,以阻止反式向13-顺式异构化。除了用于再生的脱辅基膜中残留的少量(约5%)未漂白细菌视紫红质引起的变化外,未观察到光诱导的光化学变化。所使用的技术包括在室温和液氮温度下的闪光光解以及傅里叶变换红外差光谱。当将反式固定色素掺入磷脂囊泡中时,未发现光引发质子泵浦的证据。结果表明,反式向13-顺式异构化对于细菌视紫红质的光化学转化和功能至关重要。