Mechanism and kinetics of merocyanine 540 binding to phospholipid membranes.
Mechanism and kinetics of merocyanine 540 binding to phospholipid membranes.
复制标题
部花青 540 与磷脂膜结合的机制和动力学。
作者：
A. S. Verkman
采用稳态和动态荧光及荧光停流法研究了Mercury 540（M540）与单层磷脂酰胆碱（PC）囊泡结合的物理化学机制。在530 nm激发下，水性M540在565 nm处具有发射峰，其随着膜结合单体（M）的形成而红移至580 nm;结合的二聚体（D）是非荧光的。平衡荧光滴定表明，50%的总M540分配到膜中形成D，[M540]/[PC]（Rm/p）约为0.6。在Rm/p约0.05时，M和D浓度相等。当Rm/p小于0.1时，M540具有单一的荧光寿命（tau），其随着Rm/p [tau-1（ns-1）= 0.48 + 3.3Rm/p]而减小，表明M之间形成D的快速碰撞速率。动态去极化研究表明，随着Rm/p（0.006-0.075）的增加，M的受阻旋转（在Rm/p = 0.006时，r无穷大= 0.13）变得更快（旋转速率0.2-1.9 ns-1）。N-（9-anthroyloxy）脂肪酸探针（n = 2，6，9，12，16）和绑定M540之间的能量转移的效率表明，M是平行于膜表面附近的磷脂定向;研究的效率n-AF淬火D是一致的D垂直于磷脂的取向。在M540与PC囊泡混合的停流荧光测量中，存在快速（1 ms），然后是较慢（10-50 ms）的浓度依赖性荧光增加。（250字处删节）
The physicochemical mechanism for merocyanine 540 (M540) binding to unilamellar phosphatidylcholine (PC) vesicles was examined by steady-state and dynamic fluorescence and fluorescence stopped-flow methods. At 530-nm excitation, aqueous M540 has an emission peak at 565 nm, which red shifts to 580 nm with formation of membrane-bound monomers (M); bound dimers (D) are nonfluorescent. Equilibrium fluorescence titrations show that 50% of total M540 partitions into the membrane to form D at [M540]/[PC] (Rm/p)_approximately 0.6. M and D concentrations are equal at Rm/p approximately 0.05. For Rm/p less than 0.1, M540 has a single fluorescence lifetime (tau), which decreases with Rm/p [tau-1 (ns-1) = 0.48 + 3.3Rm/p], indicating a rapid collisional rate between M to form D. Dynamic depolarization studies show that hindered rotation of M (r infinity = 0.13 at Rm/p = 0.006) becomes more rapid (rotational rate 0.2-1.9 ns-1) with increasing Rm/p (0.006-0.075). The efficiencies of energy transfer between n-(9-anthroyloxy) fatty acid probes (n = 2, 6, 9, 12, 16) and bound M540 suggest that M is oriented parallel to the phospholipids near the membrane surface; studies of efficiencies of n-AF quenching by D are consistent with an orientation of D perpendicular to the phospholipids. In stopped-flow fluorescence measurements in which M540 is mixed with PC vesicles, there is a rapid (1 ms) followed by a slower (10-50 ms) concentration-dependent fluorescence increase.(ABSTRACT TRUNCATED AT 250 WORDS)
部花青 540 可识别慢性粒细胞白血病中的红细胞膜异常。
DOI：
10.1016/0309-1651(85)90140-7
发表时间：
1985
期刊：
Cell biology international reports
影响因子：
--
作者：
Reed,JA;Kough,RH;Williamson,PL;Schlegel,RA
通讯作者：
Schlegel,RA
脂双层膜中部花青 540 弛豫动力学的温跃研究。
影响因子：
2.9
作者：
Verkman,AS;Frosch,MP
通讯作者：
Frosch,MP