Structural and functional divergence of rhodopsin super-family

(1)膜融合法视网膜蛋白结晶：(1)对法老钠藻单胞菌（Natoronomonas pharaonis halorhodopsin, pHR）的氯离子泵进行结晶，并在2处确定其结构。0。(2)在耐高温盐藻（Haloterrigena）细胞膜中发现的光驱动质子泵Deltarhodopsin（dR3）结晶，并测定其结构。7 .决议。(2)细菌视紫红质光反应中间体的结构分析：(1)测定了不同pH水平下M中间体的结构。结果表明，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的成对结构的完全破坏，而弱酸性pH下这种破坏是不完全的。(2)利用细菌视紫红质Leu93-to-Ala突变体（BR_L93A），在2处确定了O中间体的结构。(3)光驱动氯离子pu的结构分析(3)More mp(pHR):(1)在1处确定了o型蓝型和阴离子耗尽型pHR的黄色晶体结构。8 ?2. A决议。该结果使我们能够阐明氯离子从视网膜质子化希夫碱附近活性位点去除的机制。(2)在2时确定了叠氮化物配合物的m类中间体的晶体结构。3 .决议。结果表明，在质子泵循环过程中，螺旋F的细胞质一半发生了很大的结构变化。(3)在大肠杆菌中表达了pHR突变体（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的光循环不受膜电位的影响，而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主要光化学反应中间体（Baso）。7 .决议。(2)采用小角x射线散射方法研究了章鱼视紫红质（oRh）光致结构变化。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