Fluid-fluid membrane microheterogeneity: A fluorescence resonance energy transfer study
Fluid-fluid membrane microheterogeneity: A fluorescence resonance energy transfer study
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DOI：
10.1016/s0006-3495(01)76057-2
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发表时间：
2001-02-01
影响因子：
3.4
通讯作者：
Prieto, M
中科院分区：
文献类型：
--
作者：
Loura, LMS;Fedorov, A;Prieto, M
利用荧光技术（稳态荧光强度和各向异性、荧光寿命和荧光共振能量转移（FRET））研究了二肉豆烯酰基磷脂酰胆碱/胆固醇混合物的大单层囊泡。研究了三种成分（胆固醇摩尔分数0.15,0.20和0.25）和两种温度（30和40℃）在液体有序相（I,）和液体无序相（I,）共存范围内。采用两种常见的膜探针N-（7-硝基苯-2-氧-1,3-二唑-4-基）-二肉豆醇基磷脂酰乙醇胺（NBD-DMPE）和N-（丽胺(TM)-罗丹明B）-二肉豆醇基磷脂酰乙醇胺（Rh-DMPE）组成FRET对。探针的1(o)/1(d)分配系数由单个光物理测量和时间分辨FRET衰变的全局分析确定。虽然受体Rh-DMPE倾向于I相，但供体NBD-DMPE则相反。因此，由于相分离，FRET效率降低。比较分割系数的独立测量，可以检测到非常小的区域(
Large unilamellar vesicles of dimyristoylphosphatidylcholine/cholesterol mixtures were studied using fluorescence techniques (steady-state fluorescence intensity and anisotropy, fluorescence lifetime, and fluorescence resonance energy transfer (FRET)). Three compositions (cholesterol mole fraction 0.15, 0.20, and 0.25) and two temperatures (30 and 40 degreesC) inside the coexistence range of liquid-ordered (I,) and liquid-disordered (I,) phases were investigated. Two common membrane probes, N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)-dimyristoylphosphatidylethanolamine (NBD-DMPE) and N-(lissamine(TM)-rhodamine B)-dimyristoylphosphatidylethanolamine (Rh-DMPE), which form a FRET pair, were used. The 1(o)/1(d) partition coefficients of the probes were determined by individual photophysical measurements and global analysis of time-resolved FRET decays. Although the acceptor, Rh-DMPE, prefers the I, phase, the opposite is observed for the donor, NBD-DMPE. Accordingly, FRET efficiency decreases as a consequence of phase separation. Comparing the independent measurements of partition coefficient, it was possible to detect very small domains (