PHOTOSELECTION AND TRANSIENT LINEAR DICHROISM WITH ORIENTED IMMOBILIZED PURPLE MEMBRANES: EVIDENCE FOR MOTION OF THE C(20)‐METHYL GROUP OF THE CHROMOPHORE TOWARDS THE CYTOPLASMIC SIDE OF THE MEMBRANE *
PHOTOSELECTION AND TRANSIENT LINEAR DICHROISM WITH ORIENTED IMMOBILIZED PURPLE MEMBRANES: EVIDENCE FOR MOTION OF THE C(20)‐METHYL GROUP OF THE CHROMOPHORE TOWARDS THE CYTOPLASMIC SIDE OF THE MEMBRANE *
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定向固定紫色膜的光选择和瞬态线性二色性：发色团的 C(20)-甲基向膜的细胞质侧运动的证据*
DOI：
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
H. Otto
中科院分区：
文献类型：
--
作者：
M. P. Heyn;H. Otto
翻译后摘要-我们已经确定了光选择性和时间分辨线性二色性实验与定向固定紫色膜样品的细菌视紫红质的光循环过程中的生色团的跃迁偶极矩取向。与各向同性水悬浮液实验相比，该技术具有两个重要的优点：（1）消除了由于膜的旋转扩散引起的去极化，（2）大大提高了检测中间体跃迁偶极矩取向的灵敏度。将给出用于分析定向固定化膜样品的时间分辨线性二色性实验的适当方程。在从细菌视紫红质的基态到M-中间体的跃迁中，跃迁偶极矩从膜平面倾斜约3°。根据发色团平面上的现有结构信息及其C（19）和C（20）甲基的取向，如果假设共轭多烯链从C（5）到C（13）的取向在两种状态下相同，则预期跃迁偶极矩向膜平面倾斜。实验结果可以解释为C（5）到C（13）部分的链在膜平面外倾斜11°，C（20）甲基向膜的细胞质侧移动约1.7 °，而环己烯环保持固定。这一解释得到了最近关于M-中间体中生色团位置的中子衍射实验的支持。
Abstract— We have determined the transition dipole moment orientation of the chromophore during the photocycle of bacteriorhodopsin by photoselection and time‐resolved linear dichroism experiments with samples of oriented immobilized purple membranes. This technique offers two important advantages over experiments with isotropic aqueous suspensions: (1) the depolarization due to the rotational diffusion of the membranes is eliminated, (2) the sensitivity for detecting the orientation of the transition dipole moment of intermediates is greatly increased. The appropriate equations for the analysis of time‐resolved linear dichroism experiments with samples of oriented immobilized membranes will be presented. In the transition from the ground state of bacteriorhodopsin to the M‐intermediate, the transition dipole moment tilts out of the plane of the membrane by about 3°. On the basis of current structural information on the plane of the chromophore and the orientation of its C(19) and C(20) methyl groups, a tilt of the transition dipole moment into the plane of the membrane would have been expected if it is assumed that the orientation of the conjugated polyene chain from C(5) to C(13) is the same in both states. The experimental result may be explained by an 11° tilt of the C(5) to C(13) part of the chain out of the plane of the membrane with the C(20) methyl group moving towards the cytoplasmic side of the membrane by about 1.7 Å and the cyclohexene ring staying fixed. This interpretation is supported by recent neutron diffraction experiments on the chromophore position in the M‐intermediate.
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影响因子：
3.4
作者：
Lewis,BA;Rosenblatt,C;Griffin,RG;Courtemanche,J;Herzfeld,J
通讯作者：
Herzfeld,J
从吸收线性二向色性观察细菌视紫红质中质子化视网膜席夫碱基团的方向。
影响因子：
3.4
作者：
Lin,SW;Mathies,RA
通讯作者：
Mathies,RA
DOI：
10.1073/pnas.86.23.9228
发表时间：
1989-12-01
影响因子：
11.1
作者：
OTTO, H;MARTI, T;HEYN, MP
通讯作者：
HEYN, MP
中度脱水时细菌视紫红质光循环的扭曲。
影响因子：
3.4
作者：
Váró,G;Lanyi,JK
通讯作者：
Lanyi,JK
影响因子：
5.6
作者：
HENDERSON, R;BALDWIN, JM;DOWNING, KH
通讯作者：
DOWNING, KH