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Does copper (II) ethylenediaminetetraacetate disproportionate superoxide?

W F Beyer·I Fridovich
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Abstract

W. M. Willingham and J. R. J. Sorenson have recently reported [1988) Biochem. Biophys. Res. Commun. 150, 252-258) that the Cu(II)EDTA complex catalyzes the dismutation of O-2 and thereby call into question several earlier reports. These authors concluded that the widespread use of EDTA to suppress dismutation of O-2 by adventitious Cu(II) and other metals, during assays for superoxide dismutase, is unsound. We have undertaken a clarification of this issue by examining the ability of Cu(II)EDTA to catalyze the dismutation of O-2 and have found this complex to be devoid of this activity at pH 6.0 or at 7.8; whether assayed by the cytochrome c or the nitroblue tetrazolium assays. The probable reasons for the results of Willingham and Sorenson and some peculiarities of the nitroblue tetrazolium assay have been explored.

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Cytochrome c GroupEdetic AcidNitroblue TetrazoliumOxidation-ReductionSuperoxidesJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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W F Beyer, I Fridovich. 1988-08-15. Does copper (II) ethylenediaminetetraacetate disproportionate superoxide?. https://doi.org/10.1016/0003-2697(88)90173-x

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