What is unique about superoxide toxicity as compared to other biological reductants? A hypothesis.
Usually the toxicity of superoxide is attributed to its ability to reduce metal ions and subsequently reoxidation of the metal by hydrogen peroxide yields deleterious oxidizing species. As many other nontoxic biological reductants reduce metal compounds, we suggest that part of the mechanism of superoxide toxicity results from its ability to oxidize metal ions bound to biological targets, which subsequently degrade the target via an intramolecular electron transfer reaction.
Czapski
G
G
Department of Physical Chemistry, Hebrew University of Jerusalem, Israel.
Goldstein
S
S
Meyerstein
D
D
D002412:Cations; D003300:Copper / Q000378:metabolism; D005290:Ferric Compounds; D005609:Free Radicals; D007501:Iron / Q000378:metabolism; D010084:Oxidation-Reduction; D013481:Superoxides / Q000378:metabolism* / Q000633:toxicity
D002412:Cations; D005290:Ferric Compounds; D005609:Free Radicals; D013481:Superoxides; D003300:Copper; D007501:Iron