Multicolored protein conformation states in the photocycle of transducer-free sensory rhodopsin-I.
Multicolored protein conformation states in the photocycle of transducer-free sensory rhodopsin-I.
复制标题
无传感器感觉视紫红质-I 光循环中的彩色蛋白质构象状态。
DOI：
10.1016/s0006-3495(01)76029-8
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发表时间：
2001
影响因子：
3.4
通讯作者：
Bogomolni,RA
中科院分区：
文献类型：
--
作者：
Szundi,I;Swartz,TE;Bogomolni,RA
感觉视紫红质-I（SRI）是古细菌的趋光性受体，是一种存在于细胞膜上的视网膜结合蛋白，与真细菌趋化性受体同源的信号转导蛋白（HtrI）密切相关。无传感器的感觉视紫红质-I（fSRI），从细胞缺乏的HtrI，经历了光化学循环动力学不同的天然SRI。我们在这里报告在350-750 nm光谱范围和10− 7 s至1 s时间窗口内测量和分析fSRI反应的光化学动力学。SRI和HtrI之间缺乏特定的分子间相互作用，导致fSRI通过不同的分支反应早期返回基态形式，在天然SRI的光循环中不明显。发色团跃迁与蛋白质结构跃迁松散耦合。动力学中间体内的多种光谱形式的共存的多色蛋白质构象状态的概念内解释。
Sensory rhodopsin-I (SRI), a phototaxis receptor of archaebacteria, is a retinal-binding protein that exists in the cell membrane intimately associated with a signal-transducing protein (HtrI) homologous to eubacterial chemotaxis receptors. Transducer-free sensory rhodopsin-I (fSRI), from cells devoid of HtrI, undergoes a photochemical cycle kinetically different from that of native SRI. We report here on the measurement and analysis of the photochemical kinetics of fSRI reactions in the 350–750-nm spectral range and in a 10−7s to 1s time window. The lack of specific intermolecular interactions between SRI and HtrI results in early return of the ground form via distinct branching reactions in fSRI, not evident in the photocycle of native SRI. The chromophore transitions are loosely coupled to protein structural transitions. The coexistence of multiple spectral forms within kinetic intermediates is interpreted within the concept of multicolored protein conformational states.