Hypobromous acid and bromamine production by neutrophils and modulation by superoxide.

@article{Chapman2009HypobromousAA,
  title={Hypobromous acid and bromamine production by neutrophils and modulation by superoxide.},
  author={Anna L. P. Chapman and Ojia Skaff and Revathy Senthilmohan and Anthony J. Kettle and Michael Jonathan Davies},
  journal={The Biochemical journal},
  year={2009},
  volume={417 3},
  pages={
          773-81
        }
}
MPO (myeloperoxidase) catalyses the oxidation of chloride, bromide and thiocyanate to their respective hypohalous acids. We have investigated the generation of HOBr by human neutrophils in the presence of physiological concentrations of chloride and bromide. HOBr was trapped with taurine and detected by monitoring the bromination of 4-HPAA (4-hydroxyphenylacetic acid). With 100 microM bromide and 140 mM chloride, neutrophils generated HOBr and it accounted for approx. 13% of the hypohalous… 
View on PubMed
biochemj.org
47 Citations
Highly Influential Citations
1
Background Citations
15
Methods Citations
2

Figures and Tables from this paper

47 Citations

Acetaminophen (paracetamol) inhibits myeloperoxidase-catalyzed oxidant production and biological damage at therapeutically achievable concentrations.

Comparative reactivity of myeloperoxidase-derived oxidants with mammalian cells.

Urate as a Physiological Substrate for Myeloperoxidase

It is proposed that urate is a physiological substrate for MPO that is oxidized to the urate radical and the reactions of this radical with superoxide and nitric oxide provide a plausible link between urate and MPO in cardiovascular disease.

Uric acid disrupts hypochlorous acid production and the bactericidal activity of HL-60 cells

One-electron reduction of N-chlorinated and N-brominated species is a source of radicals and bromine atom formation.

Calculated reduction potentials suggest that interaction of N-halogenated species with O(2)(•-) may produce deleterious N-centered radicals and Br(•), which are implicated in the development of many human inflammatory diseases.

Measuring chlorine bleach in biology and medicine.

The effects of neutrophil-generated hypochlorous acid and other hypohalous acids on host and pathogens

The mechanisms by which neutrophils kill exogenous pathogens are provided before the generation of the oxidizing hypohalous acids HOCl, HOBr and HOSCN during the so-called oxidative burst by the enzyme myeloperoxidase is focused on.

Redox reactions and microbial killing in the neutrophil phagosome.

This review focuses on what oxidants are produced and how they kill in the phagosome, and how neutrophils kill microorganisms by an MPO-dependent mechanism that is almost certainly due to HOCl.

Myeloperoxidase-derived oxidation: mechanisms of biological damage and its prevention

  • M. Davies
  • Biology, Chemistry
    Journal of clinical biochemistry and nutrition
  • 2011
Recent developments in the understanding of the biochemistry of myeloperoxidase, the oxidants that this enzyme generates, and the use of inhibitors to inhibit such damage are reviewed.

Kinetics and Mechanism of Oxidation of d-Penicillamine in Acidified Bromate and Aqueous Bromine

The oxidation of the biologically active compound d-penicillamine (Depen) by acidic bromate has been studied. The stoichiometry of the reaction is strictly 1 : 1, in which Depen is oxidized only as…

References

SHOWING 1-10 OF 56 REFERENCES

Superoxide modulates the activity of myeloperoxidase and optimizes the production of hypochlorous acid.

It is proposed that, under physiological conditions, myeloperoxidase optimizes the production of HOCl and may potentiate oxidant damage by stimulated neutrophils.

Production of Brominating Intermediates by Myeloperoxidase

The observations raise the possibility that transhalogenation reactions initiated by phagocytes provide one pathway for mutagenesis and cytotoxicity at sites of inflammation.

Bromination and chlorination reactions of myeloperoxidase at physiological concentrations of bromide and chloride.

Assays for the chlorination activity of myeloperoxidase.

Reaction of myeloperoxidase compound I with chloride, bromide, iodide, and thiocyanate.

The results show that thiocyanate is an important substrate of myeloperoxidase in most environments and that hypothiocianate is likely to contribute to leukocyte antimicrobial activity.

Hypochlorite and superoxide radicals can act synergistically to induce fragmentation of hyaluronan and chondroitin sulphates.

It is shown that exposure of glycosaminoglycan chloramides to O2*- also promotes chloramide decomposition and glycosamine N-acetyl functions, consistent with a mechanism involving one-electron reduction of the chloramide to yield polymer-derived amidyl radicals, which subsequently undergo intramolecular hydrogen atom abstraction reactions to give carbon-centred radicals.

Comparative reactivities of various biological compounds with myeloperoxidase-hydrogen peroxide-chloride, and similarity of the oxidant to hypochlorite.

Eosinophil peroxidase-dependent hydroxyl radical generation by human eosinophils.

Thiocyanate and chloride as competing substrates for myeloperoxidase.

Thiocyanate is a major physiological substrate of myeloperoxidase, regardless of where the enzyme acts, and more consideration should be given to the oxidation products of thiOCyanate and to the role they play in host defence and inflammation.

Reactions of superoxide with myeloperoxidase.

This investigation used pulse radiolysis to determine kinetic parameters of superoxide reacting with redox forms of myeloperoxidase and used these data in a steady-state kinetic analysis to provide evidence that superoxide reacts with compound I and compound III.
...