Abstract
Interpretation of fluorescence anisotropy decay for the case of restricted rotational diffusion often requires a model. To investigate the extent of model dependence, two models are compared: a strict cone model, in which a fluorescent probe wobbles uniformly within a cone, and a Gaussian model, where the stationary distribution of the probe orientation is of a Gaussian type. For the same experimental anisotropy decay, analysis by the Gaussian model predicts a smaller value for the rate of wobbling motion than the strict cone analysis, but the difference is 35% at most; the cone angle obtained by the strict cone analysis agrees closely with the effective width of the Gaussian distribution. The results suggest that, when only two parameters (the rate and the angular range) are extracted from an experiment, the choice of a model is not crucial as long as the model contains the essential feature, e.g., the more-or-less conical restriction, of the motion under study. Model-independent analyses are also discussed.
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Selected References
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- Heyn M. P. Determination of lipid order parameters and rotational correlation times from fluorescence depolarization experiments. FEBS Lett. 1979 Dec 15;108(2):359–364. doi: 10.1016/0014-5793(79)80564-5. [DOI] [PubMed] [Google Scholar]
- Jähnig F. Structural order of lipids and proteins in membranes: evaluation of fluorescence anisotropy data. Proc Natl Acad Sci U S A. 1979 Dec;76(12):6361–6365. doi: 10.1073/pnas.76.12.6361. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kawato S., Kinosita K., Jr, Ikegami A. Dynamic structure of lipid bilayers studied by nanosecond fluorescence techniques. Biochemistry. 1977 May 31;16(11):2319–2324. doi: 10.1021/bi00630a002. [DOI] [PubMed] [Google Scholar]
- Kinosita K., Jr, Kataoka R., Kimura Y., Gotoh O., Ikegami A. Dynamic structure of biological membranes as probed by 1,6-diphenyl-1,3,5-hexatriene: a nanosecond fluorescence depolarization study. Biochemistry. 1981 Jul 21;20(15):4270–4277. doi: 10.1021/bi00518a006. [DOI] [PubMed] [Google Scholar]
- Kinosita K., Jr, Kawato S., Ikegami A. A theory of fluorescence polarization decay in membranes. Biophys J. 1977 Dec;20(3):289–305. doi: 10.1016/S0006-3495(77)85550-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lipari G., Szabo A. Effect of librational motion on fluorescence depolarization and nuclear magnetic resonance relaxation in macromolecules and membranes. Biophys J. 1980 Jun;30(3):489–506. doi: 10.1016/S0006-3495(80)85109-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Uchida T., Nagai Y., Kawasaki Y., Wakayama N. Fluorospectroscopic studies of various ganglioside and ganglioside--lecithin dispersions. Steady-state and time-resolved fluorescence measurements with 1,6-diphenyl-1,3,5-hexatriene. Biochemistry. 1981 Jan 6;20(1):162–169. doi: 10.1021/bi00504a027. [DOI] [PubMed] [Google Scholar]