Macromolecular Models by Single Molecule FRET

  • Axel T. Brunger
  • Pavel Strop
  • Marija Vrljic
  • Mark Bowen
  • Steven Chu
  • Keith R. Weninger
Conference paper
Part of the NATO Science for Peace and Security Series B: Physics and Biophysics book series (NAPSB)


Single molecule fluorescence energy transfer (FRET) experiments enable investigations of macromolecular conformation and folding by the introduction of fluorescent dyes at specific sites in the macromolecule. Multiple such experiments can be performed with different labeling site combinations in order to map complex conformational changes or interactions between multiple molecules. Distances that are derived from such experiments can be used for determination of the fluorophore positions by triangulation. When combined with a known structure of the macromolecule(s) to which the fluorophores are attached, a three-dimensional model of the system can be determined by docking calculations. Here we discuss recent applications of single molecule FRET to obtain a model of the synaptotagmin-1:SNARE complex and to study the conformation of PSD-95.


Fluorescence Resonance Energy Transfer Snare Complex Distance Restraint Docking Calculation Fluorescence Resonance Energy Transfer Efficiency 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We thank the National Institutes of Health for support (to A.T.B., RO1-MH63105), and a Career Award at the Scientific Interface from the Burroughs Wellcome Fund (to K.W.). Part of this material has been published in modified form in the Journal of Structural Biology [7].


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Copyright information

© Springer Science+Business Media Dordrecht 2012

Authors and Affiliations

  1. 1.The Howard Hughes Medical Institute and Departments of Molecular and Cellular Physiology, Neurology and Neurological Sciences, Structural Biology, and Photon ScienceStanford UniversityStanfordUSA
  2. 2.Department of Physiology and BiophysicsStony Brook University Medical CenterStony BrookUSA
  3. 3.Formerly Lawrence Berkeley National Laboratory and Physics and Cell Biology DepartmentsUniversity of California at BerkeleyBerkeleyUSA
  4. 4.Department of PhysicsNorth Carolina State UniversityRaleighUSA

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