The Binding of Divalent Ions to the Phosphoglycoprotein Phosvitin

  • Kärt Grizzuti
  • Gertrude E. Perlmann


Studies of viscosity, optical rotatory dispersion and circular dichroism on the phosphoglycoprotein Phosvitin revealed that this protein in some of its properties resembles a polyelectrolyte (1,2). As pointed out previously, this is easily understood if one considers that fifty-four per cent of all amino acid residues of phosvitin are phosphorylated (3). At neutral pH, where two hydroxyls of each phosphate group are ionized, the net electronic charge corresponds to about one negative charge per amino acid residue. Furthermore, we have shown that the presence of monovalent ions has an effect on the optical rotatory dispersion and circular dichroism of phosvitin. Since in biological processes cations, especially divalent ions, play an important role in maintaining a well-defined conformation necessary for the catalytic activity of certain enzymes, the binding studies have been extended to divalent cations with the aid of equilibrium dialysis techniques. In addition, an investigation of the effect of ion binding on the conformational characteristics of this protein has been initiated using optical methods, i.e. optical rotatory dispersion and circular dichroism.


Circular Dichroism Divalent Cation Circular Dichroism Spectrum None None Scatchard Plot 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Perlmann, G.E. and Grizzuti, K. (1970) in Liquid Crystals and Ordered Fluids, Plenum Press, p.69.Google Scholar
  2. 2.
    Grizzuti, K. and Perlmann, G.E. (1970) J. Biol. Chem. 245, 2573.Google Scholar
  3. 3.
    Allerton, S.E. and Perlmann, G.E. (1965) J. Biol. Chem. 240, 3892.Google Scholar
  4. 4.
    Scatchard, G. (1949) Ann. N.Y. Acad. Sci. 51, 660.Google Scholar
  5. 5.
    Danchin, A. and Guéron, M. (1970) Eur. J. Biochem. 16, 532.CrossRefGoogle Scholar
  6. 6.
    Danchin, A. (1972) Biopolymers 11, 1317.CrossRefGoogle Scholar
  7. 7.
    Giancotti, V., Quadrifoglio, F. and Crescenzi, V. (1973) Eur. J. Biochem. 35, 78.CrossRefGoogle Scholar
  8. 8.
    Williams, J. and Sanger, F. (1959) Biochim. Biophys. Acta 33, 294.Google Scholar
  9. 9.
    Shainkin, R. and Perlmann, G.E. (1971) J. Biol. Chem. 246, 2278.Google Scholar

Copyright information

© Plenum Press, New York 1974

Authors and Affiliations

  • Kärt Grizzuti
    • 1
  • Gertrude E. Perlmann
    • 1
  1. 1.The Rockefeller UniversityUSA

Personalised recommendations