Electro-optical Analysis of Macromolecular Structure and Dynamics

  • Dietmar PorschkeEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 875)


Electro-optical effects are induced by external electric field pulses applied to solutions or suspensions and are recorded by various optical techniques. These effects are very useful for the characterization of macromolecular structures and their dynamics in solution. One of the field-induced effects is alignment of molecular dipoles, which can be detected at a very high sensitivity by measurements of the dichroism or the birefringence. Stationary values of these optical parameters recorded at different electric field strengths can be used to characterize dipole moments and to determine the orientation of chromophores with respect to the dipole vector. The transients reflect rotational diffusion, providing a particularly accurate measure of size and shape. The internal flexibility is also reflected in these transients. Another type of field-induced effect is chemical relaxation, which can be detected selectively and is very useful for the characterization of reactions, like ligand binding and conformation changes. The techniques based on electric field effects are unique in the sense that problems can be solved, which are difficult or even impossible to be sorted out by other techniques.

Key words

Electric dichroism Electric birefringence Rotational diffusion Chemical relaxation Stopped flow 


  1. 1.
    Debye P (1929) Polare molekeln. Hirzel, LeipzigGoogle Scholar
  2. 2.
    Kerr J (1875) A new relation between electricity and light: dielectrified media birefringent. Philos Mag 50:337–348Google Scholar
  3. 3.
    Fredericq E, Houssier C (1973) Electric dichroism and electric birefringence. Clarendon, OxfordGoogle Scholar
  4. 4.
    O’Konski CT (ed) (1976) Molecular electro-optics: part 1—theory and methods. Marcel Dekker, New YorkGoogle Scholar
  5. 5.
    O’Konski CT (ed) (1978) Molecular electro-optics: part 2—applications to biopolymers. Marcel Dekker, New YorkGoogle Scholar
  6. 6.
    Stoylov SP (1991) Colloid electro-optics: theory, techniques, applications. Academic, LondonGoogle Scholar
  7. 7.
    Eigen M, DeMaeyer L (1963) Relaxation methods. In: Friess SL, Lewis ES, Weissberger A (eds) Investigation of rates and mechanisms of reactions, vol. VIII, part II. Interscience, New York, pp 895–1054.Google Scholar
  8. 8.
    Labhart H (1961) Methoden der Zuordnung von Absorptionsbanden von Farbstoffen zu berechneten Übergängen. Chimia 15:20–27Google Scholar
  9. 9.
    Meyeralmes FJ, Porschke D (1993) Mechanism of intercalation into the DNA double helix by ethidium. Biochemistry 32:4246–4253CrossRefGoogle Scholar
  10. 10.
    Bernasconi CF (1976) Relaxation kinetics. Academic, New YorkGoogle Scholar
  11. 11.
    Strehlow H (1995) Rapid reactions in solution. Weinheim, VCHGoogle Scholar
  12. 12.
    Grunhagen HH (1974) High-power square-wave pulse-generator for investigation of fast electric-field effects in solution. Messtechnik 82:19–23Google Scholar
  13. 13.
    Porschke D, Obst A (1991) An electric-field jump apparatus with ns time resolution for electrooptical measurements at physiological salt concentrations. Rev Sci Instrum 62:818–820CrossRefGoogle Scholar
  14. 14.
    Antosiewicz JM, Porschke D (2009) Effects of hydrodynamic coupling on electro-optical transients. J Phys Chem B 113:13988–13992CrossRefPubMedGoogle Scholar
  15. 15.
    Porschke D, Jung M (1985) The conformation of single stranded oligonucleotides and of oligonucleotide-oligopeptide complexes from their rotation relaxation in the nanosecond time range. J Biomol Struct Dyn 2:1173–1184CrossRefPubMedGoogle Scholar
  16. 16.
    Provencher SW (1976) Fourier method for analysis of exponential decay curves. Biophys J 16:27–41CrossRefPubMedPubMedCentralGoogle Scholar
  17. 17.
    Shah MJ (1963) Electric birefringence of bentonite. 2. An extension of saturation birefringence theory. J Phys Chem 67:2215–2219CrossRefGoogle Scholar
  18. 18.
    Porschke D (1989) Electric dichroism and bending amplitudes of DNA fragments according to a simple orientation function for weakly bent rods. Biopolymers 28:1383–1396CrossRefPubMedGoogle Scholar
  19. 19.
    Winkler-Oswatitsch R, Eigen M (1979) Art of titration—from classical end-points to modern differential and dynamic analysis. Angew Chem 18:20–49CrossRefGoogle Scholar
  20. 20.
    Porschke D, Antosiewicz JM (2007) Quantitative molecular electro-optics: Macromolecular structures and their dynamics in solution. In: Stoylov SP, Stoimenova MV (eds) Molecular and colloidal electro-optics. CRC, Boca Raton, FL, pp 55–1007Google Scholar
  21. 21.
    Porschke D (2010) Allosteric control of promoter DNA bending by cyclic AMP receptor and cyclic AMP. Biochemistry 49:5553–5559CrossRefPubMedGoogle Scholar
  22. 22.
    Wegener WA, Dowben RM, Koester VJ (1979) Time-dependent birefringence, linear dichroism, and optical-rotation resulting from rigid-body rotational diffusion. J Chem Phys 70:622–632CrossRefGoogle Scholar
  23. 23.
    Wegener WA (1986) Transient electric birefringence of dilute rigid-body suspensions at low field strengths. J Chem Phys 84:5989–6004CrossRefGoogle Scholar
  24. 24.
    Hagerman PJ, Zimm BH (1981) Monte-Carlo approach to the analysis of the rotational diffusion of wormlike chains. Biopolymers 20:1481–1502CrossRefGoogle Scholar
  25. 25.
    Antosiewicz J, Nolte G, Porschke D (1992) Modes of rotational motion of wormlike chains and the effect of charges on electrooptical transients. Macromolecules 25:6500–6504CrossRefGoogle Scholar
  26. 26.
    Porschke D (1998) Time-resolved analysis of macromolecular structures during reactions by stopped-flow electrooptics. Biophys J 75:528–537CrossRefPubMedPubMedCentralGoogle Scholar
  27. 27.
    Porschke D (2011) Electric birefringence at small angles from cross position: enhanced sensitivity and special effects. J Phys Chem 115: 4177–4183Google Scholar
  28. 28.
    Porschke D (2012) Structures during binding of cAMP receptor to promoter DNA: promoter search slowed by non-specific sites. Eur Biophys J (in press)Google Scholar

Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.Research Group Biomolecular DynamicsMax Planck Institute for Biophysical ChemistryGöttingenGermany

Personalised recommendations