Journal of Fluorescence

, Volume 3, Issue 4, pp 229–232 | Cite as

The interaction of 4′, 6-diamidino-2-phenylindole (DAPI) with pepsin

  • R. Favilla
  • A. Mazzini
  • P. Cavatorta
  • R. T. Sorbi
  • G. Sartor
Fluorescence of Biomolecules


We recently found that the fluorescent dye DAPI, well-known for its use with nucleic acids, is also able to interact with proteins as well as ordered phospholipids assemblies. The interaction of DAPI with pepsin under different conditions of pH and ionic strength was studied with fluorescence and circular dichroism techniques. From a comparison of the results obtained, the interaction appears to be rather tight and specific, dependent on both electrostatic and hydrophobic forces, and able to probe the tridimensional conformation of the protein.

Key Words

4′, 6-Diamidino-2-phenylindole (DAPI) pepsin, fluorescence, circular dichroism, binding 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    T. A. Larsen, D. S. Goodsell, D. Cascio, K. Grzeskowiak and R. E. Dickerson (1989)J. Biomol. Struct. Dynam. 7, 477–491.Google Scholar
  2. 2.
    W. D. Wilson, F. A. Tanious, H. J. Burton, R. L. Jones, K. Fox, R. L. Wydra, and L. Strekowsky (1990)Biochemistry 29, 8452–8461.PubMedGoogle Scholar
  3. 3.
    A. Mazzini, P. Cavatorta, M. Iori, R. Favilla, and G. Sartor (1992)Biophys. Chem. 42, 101–109.PubMedGoogle Scholar
  4. 4.
    R. Favilla, G. Stecconi, P. Cavatorta, G. Sartor, and A. Mazzini (1993)Biophys. Chem. 46, 217–226.PubMedGoogle Scholar
  5. 5.
    M. L. Anson (1938)J. Gen. Physiol. 22, 79.Google Scholar
  6. 6.
    J. R. Knutson, J. M. Beechem, and L. Brand (1983)Chem. Phys. Lett. 102, 501–507.CrossRefGoogle Scholar
  7. 7.
    A. J. Pesce, C. G. Rosen, and T. L. Pasby (1971)Fluorescence Spectroscopy, Marcel Dekker, New York.Google Scholar
  8. 8.
    R. Favilla and A. Mazzini (1984)Biochim. Biophys. Acta 788, 48–57.PubMedGoogle Scholar
  9. 9.
    P. Cavatorta, L. Masotti, and A. G. Szabo (1985)Biophys. Chem. 22, 11–16.Google Scholar
  10. 10.
    P. Kuzmic, C.-O. Sun, Z.-C. Zhao, and D. H. Rich (1991) in B. M. Dunn (Ed.),Structure and Function of the Aspartic Proteinases, Plenum Press, New York, pp. 75–85.Google Scholar

Copyright information

© Plenum Publishing Corporation 1993

Authors and Affiliations

  • R. Favilla
    • 1
  • A. Mazzini
    • 1
  • P. Cavatorta
    • 1
  • R. T. Sorbi
    • 2
  • G. Sartor
    • 3
  1. 1.Division of Biophysics, Department of PhysicsUniversity of ParmaParmaItaly
  2. 2.Department of Human PhysiologyUniversity of ParmaParmaItaly
  3. 3.Institute of Biological ChemistryUniversity of ParmaParmaItaly

Personalised recommendations