Abstract
We describe a new method to recover the distribution of donor-to-acceptor (D-A) distances in flexible molecules using steady-state measurements of the efficiency of fluorescence energy transfer. The method depends upon changes in the Forster distance (Ro) induced by collisional quenching of the donor emission. The Ro-dependent transfer efficiencies are analyzed using nonlinear least squares to recover the mean D-A distance and the width of the distribution. The method was developed and tested using three synthetic D-A pairs, in which the chromophores were separated by alkyl chains of varying lengths. As an example application we also recovered the distribution of distances from the single tryptophan residue in troponin I (trp 158) to acceptor-labeled cysteine 133. The half-width of the distribution increases from 12 A in the native state to 53 A when unfolded by guanidine hydrochloride. For both TnI and the three model compounds the distance distributions recovered from the steady-state transfer efficiencies were in excellent agreement with the distributions recovered using the more sophisticated frequency-domain method (Lakowicz, J.R., M.L. Johnson, W. Wiczk, A. Bhat, and R.F. Steiner. 1987. Chem. Phys. Lett. 138:587-593). The method was found to be reliable and should be generally useful for studies of conformational distributions of macromolecules.
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Selected References
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- Amir D., Haas E. Determination of intramolecular distance distributions in a globular protein by nonradiative excitation energy transfer measurements. Biopolymers. 1986 Feb;25(2):235–240. doi: 10.1002/bip.360250205. [DOI] [PubMed] [Google Scholar]
- Cantor C. R., Pechukas P. Determination of distance distribution functions by singlet-singlet energy transfer. Proc Natl Acad Sci U S A. 1971 Sep;68(9):2099–2101. doi: 10.1073/pnas.68.9.2099. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dale R. E., Eisinger J., Blumberg W. E. The orientational freedom of molecular probes. The orientation factor in intramolecular energy transfer. Biophys J. 1979 May;26(2):161–193. doi: 10.1016/S0006-3495(79)85243-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Davenport L., Dale R. E., Bisby R. H., Cundall R. B. Transverse location of the fluorescent probe 1,6-diphenyl-1,3,5-hexatriene in model lipid bilayer membrane systems by resonance excitation energy transfer. Biochemistry. 1985 Jul 16;24(15):4097–4108. doi: 10.1021/bi00336a044. [DOI] [PubMed] [Google Scholar]
- Dewey T. G., Hammes G. G. Calculation on fluorescence resonance energy transfer on surfaces. Biophys J. 1980 Dec;32(3):1023–1035. doi: 10.1016/S0006-3495(80)85033-8. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Eftink M. R., Ghiron C. A. Fluorescence quenching studies with proteins. Anal Biochem. 1981 Jul 1;114(2):199–227. doi: 10.1016/0003-2697(81)90474-7. [DOI] [PubMed] [Google Scholar]
- Estep T. N., Thompson T. E. Energy transfer in lipid bilayers. Biophys J. 1979 May;26(2):195–207. doi: 10.1016/S0006-3495(79)85244-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fung B. K., Stryer L. Surface density determination in membranes by fluorescence energy transfer. Biochemistry. 1978 Nov 28;17(24):5241–5248. doi: 10.1021/bi00617a025. [DOI] [PubMed] [Google Scholar]
- Haas E., Katchalski-Katzir E., Steinberg I. Z. Effect of the orientation of donor and acceptor on the probability of energy transfer involving electronic transitions of mixed polarization. Biochemistry. 1978 Nov 14;17(23):5064–5070. doi: 10.1021/bi00616a032. [DOI] [PubMed] [Google Scholar]
- Haas E., Wilchek M., Katchalski-Katzir E., Steinberg I. Z. Distribution of end-to-end distances of oligopeptides in solution as estimated by energy transfer. Proc Natl Acad Sci U S A. 1975 May;72(5):1807–1811. doi: 10.1073/pnas.72.5.1807. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lakowicz J. R., Gryczynski I., Cheung H. C., Wang C. K., Johnson M. L. Distance distributions in native and random-coil troponin I from frequency-domain measurements of fluorescence energy transfer. Biopolymers. 1988 May;27(5):821–830. doi: 10.1002/bip.360270509. [DOI] [PubMed] [Google Scholar]
- Lakowicz J. R., Laczko G., Cherek H., Gratton E., Limkeman M. Analysis of fluorescence decay kinetics from variable-frequency phase shift and modulation data. Biophys J. 1984 Oct;46(4):463–477. doi: 10.1016/S0006-3495(84)84043-6. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Steinberg I. Z. Long-range nonradiative transfer of electronic excitation energy in proteins and polypeptides. Annu Rev Biochem. 1971;40:83–114. doi: 10.1146/annurev.bi.40.070171.000503. [DOI] [PubMed] [Google Scholar]
- Stryer L. Fluorescence energy transfer as a spectroscopic ruler. Annu Rev Biochem. 1978;47:819–846. doi: 10.1146/annurev.bi.47.070178.004131. [DOI] [PubMed] [Google Scholar]
- Wang C. K., Cheung H. C. Energetics of the binding of calcium and troponin I to troponin C from rabbit skeletal muscle. Biophys J. 1985 Nov;48(5):727–739. doi: 10.1016/S0006-3495(85)83831-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wang C. K., Cheung H. C. Proximity relationship in the binary complex formed between troponin I and troponin C. J Mol Biol. 1986 Oct 5;191(3):509–521. doi: 10.1016/0022-2836(86)90145-2. [DOI] [PubMed] [Google Scholar]
- Wolber P. K., Hudson B. S. An analytic solution to the Förster energy transfer problem in two dimensions. Biophys J. 1979 Nov;28(2):197–210. doi: 10.1016/S0006-3495(79)85171-1. [DOI] [PMC free article] [PubMed] [Google Scholar]