Mao B, Tsuda M, Ebrey T G, Akita H, Balogh-Nair V, Nakanishi K
Biophys J. 1981 Aug;35(2):543-6. doi: 10.1016/S0006-3495(81)84809-6.
Nonbleachable rhodopsins containing retinal moieties with fixed 11-ene structures have been prepared. When the nonbleachable rhodopsin analogue corresponding to the natural pigment was flash-photolysed at 20.8 degrees C, no absorption changes occurred at the monitoring wavelengths of 380, 480, and 580 nm for the time range of 2 microseconds--10 s. This observation is in contrast to that of natural rhodopsin which showed the formation of metarhodopsin I and its decay to meta II. Irradiation of the artificial rhodopsin, 77 K, with light of 460 and 540 nm, also gave no spectral changes; in the case of natural rhodopsin, however, the irradiation leads to formation of the red-shifted intermediate bathorhodopsin. The absence of photochemistry in the artificial pigment shows that an 11-cis to trans photoisomerization of the retinal moiety is a crucial step in inducing the chain of events in te photolysis of rhodopsin.
已制备出含有具有固定11-烯结构的视黄醛部分的不可漂白视紫红质。当在20.8℃下对与天然色素相对应的不可漂白视紫红质类似物进行闪光光解时，在2微秒至10秒的时间范围内，在380、480和580nm的监测波长处未发生吸收变化。这一观察结果与天然视紫红质的情况形成对比，天然视紫红质显示出视紫红质I的形成及其向视紫红质II的衰变。在77K下用460和540nm的光照射人工视紫红质，也未产生光谱变化；然而，对于天然视紫红质，这种照射会导致形成红移中间体视紫红质原。人工色素中不存在光化学现象表明，视黄醛部分从11-顺式到反式的光异构化是引发视紫红质光解中一系列事件的关键步骤。
