Journal ArticleDOI
Toxic DNA damage by hydrogen peroxide through the Fenton reaction in vivo and in vitro.
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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Journal ArticleDOI
Protection against nuclear DNA damage offered by flavonoids in cells exposed to hydrogen peroxide: the role of iron chelation.
TL;DR: The results presented in this work strongly support the notion that intracellular binding of iron is responsible for the protection offered by flavonoids against H2O2-induced DNA damage.
Journal ArticleDOI
Oxidation Kinetics of Fe(II) in a Eutrophic Swiss Lake
TL;DR: In this paper, the rate of oxidation of ferrous iron was measured in samples from Lake Greifen, a eutrophic lake in Switzerland, using an automated flow injection analysis system employing luminol-based chemiluminescence detection of Fe(II).
Journal ArticleDOI
Reaction of chromium(VI) with glutathione or with hydrogen peroxide: identification of reactive intermediates and their role in chromium(VI)-induced DNA damage.
TL;DR: The nature of chromium(VI)-induced DNA damage appears to be dependent on the reactive intermediates, i.e. chromium (V) or hydroxyl radical, produced during the reduction of chromation(VI).
Journal ArticleDOI
Three chemically distinct types of oxidants formed by iron-mediated Fenton reactions in the presence of DNA
Y Luo,Z Han,S M Chin,Stuart Linn +3 more
TL;DR: It is hypothesize that type I oxidants are generated upon Fe2+ associated with DNA only through electrostatic interactions and cause mode I killing of E. coli; type II oxidants arise uponFe2+, which is at least partially base-associated, and cause Mode II killing; type III oxidant arise on Fe2+.
Journal ArticleDOI
Killing niche competitors by remote-control bacteriophage induction
L. Selva,D. Viana,Gili Regev-Yochay,Krzysztof Trzciński,J.M. Corpa,Iñigo Lasa,Richard P. Novick,José R. Penadés +7 more
TL;DR: This report shows that H2O2 at the concentrations typically produced by pneumococci kills lysogenic but not nonlysogenic staphylococci by inducing the SOS response, and suggests that this strategy may be in widespread use for bacterial interference.
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.