Journal ArticleDOI
Toxic DNA damage by hydrogen peroxide through the Fenton reaction in vivo and in vitro.
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TLDR
An in vitro Fenton system was established that generates DNA strand breaks and inactivates bacteriophage and that also reproduces the suppression of DNA damage by high concentrations of peroxide.Abstract:
Exposure of Escherichia coli to low concentrations of hydrogen peroxide results in DNA damage that causes mutagenesis and kills the bacteria, whereas higher concentrations of peroxide reduce the amount of such damage. Earlier studies indicated that the direct DNA oxidant is a derivative of hydrogen peroxide whose formation is dependent on cell metabolism. The generation of this oxidant depends on the availability of both reducing equivalents and an iron species, which together mediate a Fenton reaction in which ferrous iron reduces hydrogen peroxide to a reactive radical. An in vitro Fenton system was established that generates DNA strand breaks and inactivates bacteriophage and that also reproduces the suppression of DNA damage by high concentrations of peroxide. The direct DNA oxidant both in vivo and in this in vitro system exhibits reactivity unlike that of a free hydroxyl radical and may instead be a ferryl radical.read more
Citations
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Oxidative DNA damage mediated by copper(II), iron(II) and nickel(II) Fenton reactions: evidence for site-specific mechanisms in the formation of double-strand breaks, 8-hydroxydeoxyguanosine and putative intrastrand cross-links
TL;DR: The results suggest that a site-specific mechanism is involved in the formation of double-strand breaks and, to a lesser extent, 8-OHdG and the putative intrastrand cross-links, while the Formation of single-Strand breaks is more likely to involve generation of hydroxyl radicals in solution.
Journal ArticleDOI
Fenton-like reaction catalyzed by the rare earth inner transition metal cerium.
TL;DR: It is proposed that cerium is capable of redox-cycling with peroxide to generate damaging oxygen radicals in a Fenton-like reaction with hydrogen peroxide.
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In Staphylococcus aureus, fur is an interactive regulator with PerR, contributes to virulence, and Is necessary for oxidative stress resistance through positive regulation of catalase and iron homeostasis.
TL;DR: It is determined that Fur functions, either directly or indirectly, as an iron-dependent positive regulator of katA expression, which demonstrates the importance in vivo of iron homeostasis and oxidative stress resistance regulation in S. aureus.
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Catalase (KatA) and Alkyl Hydroperoxide Reductase (AhpC) Have Compensatory Roles in Peroxide Stress Resistance and Are Required for Survival, Persistence, and Nasal Colonization in Staphylococcus aureus
Kate Cosgrove,Graham Coutts,Ing-Marie Jonsson,Andrej Tarkowski,John F. Kokai-Kun,James J. Mond,Simon J. Foster +6 more
TL;DR: Oxidative-stress resistance is an important factor in the ability of S. aureus to persist in the hospital environment and so contribute to the spread of human disease.
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Catalases in Plants: Gene Structure, Properties, Regulation, and Expression
TL;DR: Catalase has been found in all plants examined, and has been most thoroughly studied biochemically, genetically, and molecularly in the agronomically important species Zea mays L. (Scandalios 1990).
References
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Journal ArticleDOI
The biology of oxygen radicals
TL;DR: The reactive superoxide radical, O2-, formerly of concern only to radiation chemists and radiobiologists, is now understood to be a normal product of the biological reduction of molecular oxygen.
Journal ArticleDOI
The catalytic decomposition of hydrogen peroxide by iron salts
Fritz Haber,Joseph Weiss +1 more
TL;DR: Wansbrough-Jones as discussed by the authors gave the manuscript of this paper to Professor Sir William Pope, but the final revision for the press had not been made and in its original from the paper was not suitable for publication in an English journal; but since, Professor Haber had considered carefully how he wished to present the results embodied in it, the form and sequence of the paper remain unmodified.