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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The induction of oxidative enzymes in Streptomyces coelicolor upon hydrogen peroxide treatment
TL;DR: Streptomyces coelicolor (Muller) became resistant to killing by hydrogen peroxide (H2O2) when pretreated with non-lethal concentrations of H2 O2, suggesting that there exists a global regulation of oxidative response in S. coel Nicolor.
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Prospective case-cohort study of intestinal colonization with enterococci that produce extracellular superoxide and the risk for colorectal adenomas or cancer
Michael D Winters,Michael D Winters,Tiffany L Schlinke,Tiffany L Schlinke,Wendy A. Joyce,Wendy A. Joyce,Stephen R Glore,Stephen R Glore,Mark M. Huycke,Mark M. Huycke +9 more
TL;DR: A prospective case-cohort study of intestinal colonization with enterococci that produce extracellular superoxide and the risk for colorectal adenomas or cancer is presented.
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Characterization of a Peroxide-Resistant Mutant of the Anaerobic Bacterium Bacteroides fragilis
Edson R. Rocha,C. Jeffrey Smith +1 more
TL;DR: Constutive expression of KatB and of the AhpC and Dps homologues in the H2O2-resistant mutant suggests that these proteins may share a common oxidative stress transcriptional regulator and may be involved in B. fragilis peroxide resistance.
Journal ArticleDOI
Synthesis of an Ultrafine Iron and Soot Aerosol for the Evaluation of Particle Toxicity.
TL;DR: A diffusion flame system was used to generate an aerosol of soot and iron oxide as mentioned in this paper, where the primary fuel was ethylene and the iron was introduced by passing ethylene over liquid iron pentacarbonyl.
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An oxygen dependence in chromium mutagenesis.
TL;DR: The data support a role for oxygen radicals in chromium-mediated mutagenesis and suggests at least two pathways by which chromium compounds can induce mutations.
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.