The production of activated oxygen species by an interaction of methemoglobin with ascorbate

doi:10.1016/0006-291X(83)91396-7

Biochemical and Biophysical Research Communications

Volume 111, Issue 3, 29 March 1983, Pages 980-987

https://doi.org/10.1016/0006-291X(83)91396-7 Get rights and content

Abstract

Ascorbate reacts with methemoglobin to produce reactive oxygen species, most probably hydroxyl radicals. The main features of this system are: a) disappearance of ascorbate; b) consumption of oxygen with an ascorbate/O₂ stoichiometry of 2:1; c) requirement of unliganded heme iron; d) formation of H₂O₂. The proposed mechanism involves an ascorbate-mediated interconversion of methemoglobin and oxy-hemoglobin, resulting in the production of H₂O₂. This product is decomposed by hemoglobin to produce hydroxyl radicals according to a Fenton-like reaction in which ascorbate recycles methemoglobin to hemoglobin. Alternative pathways of formation and of decomposition of H₂O₂ in this system appear to play a minor role.

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The production of activated oxygen species by an interaction of methemoglobin with ascorbate

Abstract

FEBS Letters

Arch. Biochem. Biophys

J. Biol. Chem

Biochem. Biophys. Res. Comm

Biochim. Biophys. Acta

Anal. Biochem

J. Biol. Chem

Biochem. Biophys. Res. Comms

J. Biol. Chem

FEBS Letters

J. Biol. Chem

FEBS Letters

FEBS Letters