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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Evidence for two NAD kinases in Salmonella typhimurium.
Weili Cheng,John R. Roth +1 more
TL;DR: It is proposed that Salmonella typhimurium has two NAD kinases, one encoded by the nadF and one by theNadG gene, supported by the fact that temperature-sensitive mutants of both genes produce kinase activity with altered heat stability.
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Rapid analysis of base-pair substitutions induced by mutagenic drugs through their oxygen radical or epoxide derivatives
TL;DR: This study showed that analysis of mutations is achievable using the battery of strains listed above, and elucidated the selectivity of the Ames II strains, with AT targets showing little or no sensitivity to reversion.
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Disrupting ROS-protection mechanism allows hydrogen peroxide to accumulate and oxidize Sb(III) to Sb(V) in Pseudomonas stutzeri TS44
TL;DR: It is proposed that a disruption of the pathway involved in ROS-protection allowed H2O2 to accumulate and the accumulated H2 O2 is correlated to the increased Sb(III) oxidation rate.
Journal ArticleDOI
Molecular characterization of the Fur protein of Listeria monocytogenes
TL;DR: Under in vitro conditions, the affinity of the Fur protein for the 19 bp Fur box sequence does not require iron, but iron availability regulates fur transcription in vivo, suggesting that the regulation by Fur in this intracellular pathogen may be dependent on either the structure of the DNA binding domain or other intrACEllular factors yet to be identified.
Journal ArticleDOI
Facile production of silver-reduced graphene oxide nanocomposite with highly effective antibacterial performance
TL;DR: In this paper, a bottom-up strategy of growing reduced graphene oxide (rGO) from a cellulose acetate and silver nitrate precursor in one step without tedious solution exfoliation and chemical treatment steps is presented.
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.