Mg2+ — Inner Sphere Complexes at “Ends” and “Bends” of Polynucleotides and their Potential Role as Long Range Inducers of Conformation Changes

  • Dietmar Porschke
Part of the NATO ASI Series book series (NSSA, volume 110)


A short review is given on Mg2+-binding to oligo- and polynucleotides with special emphasis on the formation of inner sphere complexes. Due to the rather slow exchange of ligands in the inner sphere of Mg2+ these complexes are localised at a given site with a relatively long lifetime, whereas outer sphere complexes are much more mobile (ion atmosphere binding). Measurements of the binding kinetics demonstrate that Mg2+ binds to polymers like poly(A) mainly in the form of outer sphere complexes, whereas short oligoriboadenylates are shown to form inner sphere complexes. Evidence is presented that the measured increase of the inner sphere binding constant with decreasing chain length results from preferential inner sphere complexation at chain ends. Inner sphere complexes are also formed at “bends” of polynucleotide chains. An example is given for the anticodon loop of tRNAPhe, where Mg2+ preferentially forms an inner sphere complex with one of two loop conformations. The special properties of Mg2+-ligands may be used for transmission of a “signal” along a polynucleotide chain.


Electric Field Pulse Conformation Change Sphere Complex Hydration Sphere tRNA Molecule 
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  1. 1.
    H. Diebler, M. Eigen and G.G. Hammes, Z. Naturf. 15b, 554 (1960)Google Scholar
  2. 2.
    M. Eigen, Pure Appl. Chem. 6, 97 (1963)CrossRefGoogle Scholar
  3. 3.
    J. Neely and R. Connick, J. Amer. Chem. Soc. 92, 3476 (1970)CrossRefGoogle Scholar
  4. 4.
    D. Porschke, Biophys. Chem. 4, 383 (1976)CrossRefGoogle Scholar
  5. 5.
    G. Manning, Quart. Rev. Biophysics 11, 179 (1978)CrossRefGoogle Scholar
  6. 6.
    D. Porschke, Nucleic Acids Research 6, 883 (1979)CrossRefGoogle Scholar
  7. 7.
    D. Porschke and M. Jung, J. Biomol. Structure & Dynamics 2, 1173 (1985)Google Scholar
  8. 8.
    G.J. Quigley and A. Rich, Science 194, 791 (1976)CrossRefGoogle Scholar
  9. 9.
    D. Labuda and D. Porschke, Biochemistry 21, 49 (1982)CrossRefGoogle Scholar
  10. 10.
    A. Jack, J.E. Ladner, D. Rhodes and A. Klug, J. Mol. Biol. 111, 315 (1977)CrossRefGoogle Scholar
  11. 11.
    G.J. Quigley, M.M. Teeter and A. Rich, Proc. Natl. Acad. Sci. USA 70, 2683 (1978)Google Scholar
  12. 12.
    M.M. Teeter, G.J. Quigley and A. Rich in Nucleic Acid-Metal Ion Interactions, Ed. T.G. Spiro, John Wiley & Sons, New York (1980)Google Scholar
  13. 13.
    C. Woese, Nature 226, 817 (1970)CrossRefGoogle Scholar
  14. 14.
    D. Labuda, G. Striker and D. Porschke, J. Mol. Biol. 174, 587 (1984)CrossRefGoogle Scholar
  15. 15.
    H.G. Gassen, Progress in Nucleic Acid Research and Mol. Biology 24, 57 (1980)CrossRefGoogle Scholar
  16. 16.
    R. Potts, M.J. Fournier and N.C. Ford Jr., Nature 268, 563 (1977)CrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1986

Authors and Affiliations

  • Dietmar Porschke
    • 1
  1. 1.Max Planck Institut für biophysikalische ChemieGöttingenGermany

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