Structural and functional divergence of rhodopsin super-family

(1)膜熔融法结晶视网膜蛋白质：(1)将嗜盐嗜盐单胞菌(Natoronomonas pharaonis pharaonis halorhobisin，PhR)的氯离子泵结晶，并测定其结构，分辨率为2.0A。(2)结晶嗜热嗜盐菌细胞膜中的光驱动质子产物Deltarho品sin(DR3)，并测定其结构，分辨率为2.7A。结果表明，在中性pH下，M中间体的形成伴随着质子释放通道中两个谷氨酸对结构的完全破坏，而在弱酸性pH下，这种破坏是不完全的。(2)利用细菌视紫红质的Leu93-to-Ala突变体(BR_L93A)，在2.3A分辨率下确定了O中间体的结构。(3)光驱动氯离子PU…的结构分析更多的MP(Phr)：(1)在1.8±2.0A的分辨率下测定了PHR的O-型蓝型和黄色阴离子耗尽型的晶体结构。这一结果使我们能够阐明氯离子从视网膜质子化Schiff碱附近的活性中心去除的机理。(2)以2.3A的分辨率测定了叠氮类化合物的M-中间体的晶体结构。结果表明，在质子泵周期中，螺旋F的细胞质部分发生了较大的结构变化。(3)在大肠杆菌中表达了一个突变体phr(phr_ΔBC)，其中跨膜螺旋B和C之间的长环部分缺失。结果表明，phr_ΔBC的光周期不受膜电位的影响，而对氯离子的吸收过程比野生型phr快得多。(4)鱿鱼视紫红质的结构分析(1)测定了鱿鱼视紫红质的初级光化学反应中间体(BASO)的分辨率为2.7A。(2)用小角X射线散射法研究了章鱼视紫红质在光诱导下的结构变化。较少

(1) Crystallization of retinal proteins by the membrane fusion method:(1) The chloride ion pump from Natoronomonas pharaonis, pharaonis halorhodopsin(pHR), was crystallized, and its structure was determined at 2. 0 Aresolution.(2) Deltarhodopsin(dR3), a light-driven proton pomp found in the cell membrane of Haloterrigena thermotolerans, was crystallized, and its structure was determined at 2. 7 A resolution.(2) Structural analyses of the photoreaction intermediates of bacteriorhodopsin:(1) The structure of the M intermediate was determined at various pH levels. It was shown that the formation of M intermediate at neutral pH is accompanied by a complete destruction of the paired structure of two glutamates in the proton release channel, while this destruction is incomplete at a weakly acidic pH.(2) Using the Leu93-to-Ala mutant(BR_L93A) of bacteriorhodopsin, the structure of the O intermediate was determined at 2. 3 A resolution(3) Structural analyses of the light-driven chloride ion pu … More mp(pHR):(1) The crystal structures of the O-like blue form and the yellow anion-depleted form of pHR were determined at 1. 8 ? 2. 0 A resolutions. The result allowed us to elucidate the mechanism by which the chloride ion is removed from the active site near the protonated Schiff base of retinal.(2) The crystal structure of an M-like intermediate of the pHR-azide complex was determined at 2. 3 A resolution. It is shown that the cytoplasmic half of helix F undergoes a large structural change during the proton pumping cycle(3) A mutant of pHR(pHR_ΔBC) in which a long loop between transmembrane helices B and C was partially deleted was expressed in E. coli. It was shown that the photocycle of pHR_ΔBC is not influenced by the membrane potential, while the uptake process of chloride ion is much faster than observed in the wild-type pHR.(4) Structural analyses of squid rhodopsin(1) The primary photochemical reaction intermediate(Baso) of squid rhodopsin was determined at 2. 7 A resolution.(2) Light-induced structural changes in octopus rhodopsin(oRh) were investigated by small-angle X-ray scattering method. Less