Lateral diffusivity of lipid analogue excimeric probes in dimyristoylphosphatidylcholine bilayers.
Lateral diffusivity of lipid analogue excimeric probes in dimyristoylphosphatidylcholine bilayers.
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二肉豆蔻酰磷脂酰胆碱双层中脂质类似物准分子探针的横向扩散性。
DOI:
10.1016/s0006-3495(90)82530-3
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发表时间:
1990
影响因子:
3.4
通讯作者:
Eisinger,J
中科院分区:
文献类型:
--
作者:
Sassaroli,M;Vauhkonen,M;Perry,D;Eisinger,J
The lateral mobility of pyrenyl phospholipid probes in dimyristoylphosphatidylcholine (DMPC) vesicles was determined from the dependence of the pyrene monomeric and excimeric fluorescence yields on the molar probe ratio. The analysis of the experimental data makes use of the milling crowd model for two-dimensional diffusivity and the computer simulated random walks of probes in an array of lipids. The fluorescence yields for 1-palmitoyl-2-(1'-pyrenedecanoyl)phosphatidylcholine (py10PC) in DMPC bilayers are well fitted by the model both below and above the fluid-gel phase transition temperature (Tc) and permit the evaluation of the probe diffusion rate (f), which is the frequency with which probes take random steps of length L, the host membrane lipid-lipid spacing. The lateral diffusion coefficient is then obtained from the relationship D=fL2/4. In passing through the fluid-gel phase transition of DMPC (Tc = 24 degrees C), the lateral mobility of py10PC determined in this way decrease only moderately, while D measured by fluorescence photobleaching recovery (FPR) experiments is lowered by two or more orders of magnitude in gel phase. This difference in gel phase diffusivities is discussed and considered to be related either to (a) the diffusion length in FPR experiments being about a micrometer or over 100 times greater than that of excimeric probes (approximately 1 nm), or (b) to nonrandomicity in the distribution of the pyrenyl probes in gel phase DMPC. At 35 degrees C, in fluid DMPC vesicles, the diffusion rate is f=1.8 x 10(8) s-1, corresponding to D=29 microns2 s-1, which is about three times larger than the value obtained in FPR experiments. The activation energy for lateral diffusion in fluid DMPC was determined to be 8.0 kcal/mol.
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DOI:
10.1073/pnas.75.6.2759
发表时间:
1978
影响因子:
11.1
作者:
B. Smith;H. Mcconnell
通讯作者:
H. Mcconnell
DOI:
--
发表时间:
1989
期刊:
影响因子:
--
作者:
J. Eisinger
通讯作者:
J. Eisinger
影响因子:
3.4
作者:
Vauhkonen,M;Sassaroli,M;Somerharju,P;Eisinger,J
通讯作者:
Eisinger,J
影响因子:
2.9
作者:
Enshinn Wu;Ken Jacobson;Demetrios Papahadjopoulos
通讯作者:
Demetrios Papahadjopoulos
DOI:
--
发表时间:
1974
期刊:
影响因子:
--
作者:
K. Naqvi
通讯作者:
K. Naqvi