The exchangeability of copper at active sites in ascorbic acid oxidase

https://doi.org/10.1016/0003-9861(62)90021-8Get rights and content

Abstract

The exchange reaction between the copper protein, ascorbic acid oxidase and radioactive Cu64 (cupric) ions has been reinvestigated under a variety of conditions.

It has been confirmed that the exchange with the nonfunctioning (“resting”) enzyme is very much less than that, observed with the functioning enzyme and is dependent on the specific activity.

The very rapid exchange observed with the functioning enzyme increases with the amount of substrate oxidized, and is a consequence of the catalytic mechanism rather than the processes by which the enzyme becomes inactivated.

It has been shown that the exchange occurs at copper sites involved in the enzyme activity and such sites remain active following the exchange.

The results are discussed in terms of different types of copper and copper bondings in the enzyme.

References (23)

  • F.T. Dunn et al.

    J. Biol. Chem

    (1951)
  • M. Joselow et al.

    J. Biol. Chem

    (1951)
    M. Joselow et al.

    J. Biol. Chem

    (1951)
  • C.R. Dawson
  • C.R. Dawson et al.
  • O. Warburg

    Biochem. Z

    (1927)
  • O. Warburg et al.

    Biochem. Z

    (1927)
  • A. Martell et al.

    Chemistry of Metal Chelate Compounds

  • P.L. Lovett-Janison et al.

    J. Am. Chem. Soc

    (1940)
  • H.G. Steinman et al.

    J. Am. Chem. Soc

    (1942)
  • W.H. Powers et al.

    J. Gen. Physiol

    (1943)
    W.H. Powers et al.

    J. Gen. Physiol

    (1943)
  • N. Benhamou et al.

    Arch. Biochem. Biophys

    (1959)
  • Cited by (3)

    • Ascorbate Oxidase

      1979, Methods in Enzymology
    1

    Taken from a dissertation presented to the faculty of Columbia University by Richard J. Magee in partial fulfillment of the requirements for the degree of Doctor of Philosophy. Present address: American Cyanamid Co., Princeton, N. J.

    View full text