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. 1990 Jul;87:237–243. doi: 10.1289/ehp.9087237

Redox cycling of radical anion metabolites of toxic chemicals and drugs and the Marcus theory of electron transfer.

R P Mason 1
PMCID: PMC1567813  PMID: 2176587

Abstract

A wide variety of aromatic compounds are enzymatically reduced to form anion free radicals that generally contain one more electron than their parent compounds. In general, the electron donor is any of a wide variety of flavoenzymes. Once formed, these anion free radicals reduce molecular oxygen to superoxide and regenerate the parent compound unchanged. The net reaction is the oxidation of the flavoenzyme's coenzymes and the reduction of molecular oxygen. This catalytic behavior has been described as futile metabolism or redox cycling. Electron transfer theory is being applied to these reactions and, in some cases, has successfully correlated Vmax and Km with the reduction potentials of the aromatic compounds.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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