Flavin coenzymes in oxidoreduction and oxidant stress
THE CONTEXT
Flavin coenzymes act as electron carriers in metabolic oxidation reactions; their reoxidation can generate oxidant species.
Metabolic roles
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Flavin-dependent oxidoreduction reactions include the mitochondrial respiratory chain, key enzymes in fatty acid and amino acid oxidation, and the citric acid cycle.
Reoxidation and oxidant generation
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In oxygenases and mixed-function oxidases, reoxidation of reduced flavin proceeds through formation of the flavin radical and flavin hydroperoxide.
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This process generates superoxide and perhydroxyl radicals and hydrogen peroxide as intermediates.
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Consequently, flavin oxidases contribute significantly to total oxidant stress in the body.