Advertisement

Springer Nature is making SARS-CoV-2 and COVID-19 research free. View research | View latest news | Sign up for updates

Studies on the active center of pancreatic amylase

II. Small angle X-ray scattering investigations

Summary

  1. 1.

    The radius of gyration of α-amylase is 26.9 Å, as found by means of small angle X-ray scattering. This value decreases by 0.5 Å if amylase binds three moles ofβ-cyclodextrin per mole enzyme.

  2. 2.

    In case of partial saturation, the solution contains only saturated amylase-cyclodextrin complexes (amylase/cyclodextrin molar ratio 1:3) and amylase molecules free of cyclodextrin. The binding of β-cyclodextrin follows the all-or-none mechanism.

  3. 3.

    The specifically bound β-cyclodextrin molecules are accommodated in a trough of the amylase molecule. The plane of bound cyclodextrin is perpendicular to the longitudinal axis of the trough. It is suggested that the helical substrate, amylose, binds in this trough, too.

This is a preview of subscription content, log in to check access.

References

  1. 1.

    S. Móra, I. Simon and P. Elődi, previous paper in this issue (1974).

  2. 2.

    F. Hatfaludi, T. Strashilov and F. B. Straub, Acta Biochim. Biophys. Acad. Sci. Hung. 1 39–44 (1966).

  3. 3.

    A. Guinier and G. Fournet, Small-Angle X-ray Scattering. Academic Press. New York (1955).

  4. 4.

    I. Simon, J. Appl. Cryst. 4 317–318 (1971).

  5. 5.

    I. Simon, Eur. J. Biochem. 30 184–189 (1972).

  6. 6.

    A. McPherson and A. Rich, Biochim. Biophys. Acta. 285 493–497 (1972).

  7. 7.

    P. Závodszky and P. Elődi, Acta Biochim. Biophys. Acad. Sci. Hung. 5 225 (1970).

  8. 8.

    G. Porod, Acta Physica Austrica 2 255–292 (1948).

  9. 9.

    J. A. Thoma and D. E. Koshland, J. Biol. Chem. 235 2511–2517 (1960).

  10. 10.

    F. B. Straub and G. Szabolcsi, in Mol. Biol. p. 182–187., Nauka. Moscow (1964).

Download references

Author information

Additional information

An invited article

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Simon, I., Móra, S. & Elödi, P. Studies on the active center of pancreatic amylase. Mol Cell Biochem 4, 211–216 (1974). https://doi.org/10.1007/BF01731483

Download citation

Keywords

  • Amylase
  • Active Center
  • Cyclodextrin
  • Small Angle
  • Amylose