Exploring membrane organization and dynamics by the wavelength-selective fluorescence approach
Exploring membrane organization and dynamics by the wavelength-selective fluorescence approach
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DOI：
10.1016/s0009-3084(02)00174-3
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发表时间：
2003-01-01
影响因子：
3.4
通讯作者：
Chattopadhyay, A
中科院分区：
文献类型：
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作者：
Chattopadhyay, A
波长选择性荧光包括一组基于荧光光谱中的红边效应的方法，其可用于直接监测复杂生物系统中荧光团周围的环境和动态。由激发波长向吸收带的红边偏移引起的最大荧光发射波长向更高波长的偏移被称为红边激发偏移（REES）。这种效应主要是观察到极性荧光团在运动受限的介质，如非常粘稠的溶液或凝聚相，其中偶极弛豫时间的溶剂壳周围的荧光团是可比的或长于其荧光寿命。REES产生于激发态荧光团周围的溶剂弛豫（重定向）的缓慢速率，这是对紧邻荧光团的溶剂分子施加的运动限制的函数。利用这种方法，它成为可能的探测环境本身的迁移率参数（这是由松弛溶剂分子表示），仅使用荧光团作为报告基团。此外，由于生物系统中普遍存在的溶剂是水，因此在这种情况下获得的信息将来自“光学沉默”的水分子。这使得REES和相关技术非常有用，因为水合作用在大量重要的细胞事件中起着至关重要的调节作用，包括脂质-蛋白质相互作用和离子转运。膜中的界面区域具有独特的运动和介电特性，是显示波长选择性荧光效应的合适环境。REES和相关技术（波长选择性荧光方法）作为一个强大的工具来监测的组织和动态的探针和肽绑定到膜，胶束和反胶束的应用进行了讨论。(C)2002爱思唯尔科学爱尔兰有限公司保留所有权利。
Wavelength-selective fluorescence comprises a set of approaches based on the red edge effect in fluorescence spectroscopy which can be used to directly monitor the environment and dynamics around a fluorophore in a complex biological system. A shift in the wavelength of maximum fluorescence emission toward higher wavelengths, caused by a shift in the excitation wavelength toward the red edge of absorption band, is termed red edge excitation shift (REES). This effect is mostly observed with polar fluorophores in motionally restricted media such as very viscous solutions or condensed phases where the dipolar relaxation time for the solvent shell around a fluorophore is comparable to or longer than its fluorescence lifetime. REES arises from slow rates of solvent relaxation (reorientation) around an excited state fluorophore which is a function of the motional restriction imposed on the solvent molecules in the immediate vicinity of the fluorophore. Utilizing this approach, it becomes possible to probe the mobility parameters of the environment itself (which is represented by the relaxing solvent molecules) using the fluorophore merely as a reporter group. Further, since the ubiquitous solvent for biological systems is water, the information obtained in such cases will come from the otherwise 'optically silent' water molecules. This makes REES and related techniques extremely useful since hydration plays a crucial modulatory role in a large number of important cellular events, including lipid-protein interactions and ion transport. The interfacial region in membranes, characterized by unique motional and dielectric characteristics, represents an appropriate environment for displaying wavelength-selective fluorescence effects. The application of REES and related techniques (wavelength-selective fluorescence approach) as a powerful tool to monitor the organization and dynamics of probes and peptides bound to membranes, micelles, and reverse micelles is discussed. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.