On the Bioactive Conformation of the Rhodopsin Chromophore: Absolute Sense of Twist around the 6-s-cis Bond
作者:Yukari Fujimoto、Jun Ishihara、Shojiro Maki、Naoko Fujioka、Tao Wang、Takumi Furuta、Nathan Fishkin、Babak Borhan、Nina Berova、Koji Nakanishi
DOI:10.1002/1521-3765(20011001)7:19<4198::aid-chem4198>3.0.co;2-x
日期:2001.10.1
carrying the ring moiety. The GTP-binding assay of pigment Rh-(2a), incorporating retinal analogue 2a, has shown that its activity is 80% that of the native pigment. That is, the overall conformation around the 6-s bond is retained in the steps leading to G-protein activation.
将视蛋白与合成的6-s锁定类视色素2a和2b一起孵育只会导致由α锁定的2a形成色素,其CD光谱与天然视紫红质(Rh)相似。这表明视紫红质中发色团的6-s键为顺式,且其螺旋度为负。较早的交联研究表明,在batho-Rh到lumi-Rh的转化中发生的11-顺式到全反式光异构化引起了带有环部分的一侧的翻转。结合视网膜类似物2a的色素Rh-(2a)的GTP结合测定表明,其活性是天然色素的80%。即,在导致G蛋白活化的步骤中保留了6-s键周围的整体构象。