Measuring Two at the Same Time: Combining Magnetic Tweezers with Single-Molecule FRET

  • Marko Swoboda
  • Maj Svea Grieb
  • Steffen Hahn
  • Michael SchlierfEmail author
Part of the Experientia Supplementum book series (EXS, volume 105)


Molecular machines are the workhorses of the cell that efficiently convert chemical energy into mechanical motion through conformational changes. They can be considered powerful machines, exerting forces and torque on the molecular level of several piconewtons and piconewton-nanometer, respectively. For studying translocation and conformational changes of these machines, fluorescence methods, like FRET, as well as “mechanical” methods, like optical and magnetic tweezers, have proven well suited over the past decades. One of the current challenges in the field of molecular machines is gaining maximal information from single-molecule experiments by simultaneously measuring translocation, conformational changes, and forces exerted by these machines. In this chapter, we describe the combination of magnetic tweezers with single-molecule FRET for orthogonal simultaneous readout to maximize the information gained in single-molecule experiments.


Magnetic tweezers and single-molecule FRET DNA manipulation Conformational changes Molecular machines 



Charge-coupled device


Dichroic mirror


Deoxyribonucleic acid


Deoxyribonucleoside triphosphate


Deoxythymidine triphosphate


Deoxyuridine triphosphate


Electron multiplying charge-coupled device


Förster resonance energy transfer


Graphics processing unit


Holliday junction


Lookup table


Polymerase chain reaction


Resonant-cavity light-emitting diode


Ribonucleic acid


Region of interest


Total internal reflection fluorescence



We gratefully acknowledge numerous discussions with the group of Ralf Seidel, in particular Ralf Seidel, Alexander Huhle, and Friedrich Schwarz. Furthermore, discussions and software support by members of the Schlierf lab are highly appreciated. This work was supported by grants from BMBF 03Z2EN11 (to M.S.).


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Copyright information

© Springer Basel 2014

Authors and Affiliations

  • Marko Swoboda
    • 1
  • Maj Svea Grieb
    • 1
  • Steffen Hahn
    • 1
  • Michael Schlierf
    • 1
    Email author
  1. 1.BCUBE - Center for Molecular BioengineeringTechnische Universität DresdenDresdenGermany

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