Eyring G, Curry B, Mathies R, Fransen R, Palings I, Lugtenburg J
Biochemistry. 1980 May 27;19(11):2410-8. doi: 10.1021/bi00552a020.
Resonance Raman spectra of visual pigment analogues have been used to evaluate various models for the structure of the retinal chromophore in bathorhodopsin. Deuteration or removal of the 18-methyl on the beta-ionyl ring or of the 19-methyl on the polyene chain demonstrates that the three intense low wavenumber bands of bathorhodopsin at 853, 875, and 920 cm-1 are not due to exomethylene or ring modes. Rather, assignment of these lines to out-of-plane vinyl hydrogen motions on the chain best accounts for the experimental data. Our calculations show that the intensity of these vibrations can be explained by twists of 10-30 degrees about chain single bonds. The 1100-1400-cm-1 Raman fingerprint indicates that the configuration of the double bonds is trans. This suggests that the structure of the bathorhodopsin chromophore is twisted all-trans.
视觉色素类似物的共振拉曼光谱已被用于评估视紫红质中视黄醛发色团结构的各种模型。β-紫罗酮环上的18-甲基或多烯链上的19-甲基的氘代或去除表明，视紫红质在853、875和920 cm-1处的三个强烈低波数带不是由于亚甲基或环模式。相反，将这些谱线归因于链上平面外乙烯基氢的运动最能解释实验数据。我们的计算表明，这些振动的强度可以通过围绕链单键10-30度的扭曲来解释。1100-1400 cm-1的拉曼指纹表明双键的构型是反式的。这表明视紫红质发色团的结构是扭曲的全反式结构。
