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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Journal ArticleDOI
Genetic-Metabolic Coupling for Targeted Metabolic Engineering
TL;DR: This study identifies effectors of the OxyR-Fur stress response that limit thiamine biosynthesis via alternative regulation of iron storage and Fe-S cluster inclusion in enzymes.
Journal ArticleDOI
Zinc-dependent substrate-level phosphorylation powers Salmonella growth under nitrosative stress of the innate host response.
Liam F. Fitzsimmons,Lin Liu,Steffen Porwollik,Sangeeta Chakraborty,Prerak T. Desai,Timothy Tapscott,Calvin A. Henard,Michael McClelland,Andrés Vázquez-Torres,Andrés Vázquez-Torres +9 more
TL;DR: A previously unsuspected conjunction between zinc homeostasis, glucose metabolism and cellular energetics in the adaptation of intracellular Salmonella to the reactive nitrogen species synthesized in the innate host response is uncovered.
Journal ArticleDOI
Stimulatory effects of chitinase on growth and immune defense of orange-spotted grouper (Epinephelus coioides).
TL;DR: The cDNA fragment encoding orange-spotted grouper chitinase1 was subcloned into pPIC3.5K vector and expressed in Pichia pastoris GS115, and the recombinant protein had obvious effects on growth and immune defense.
Proceedings ArticleDOI
Physical and biological mechanisms of plasma interaction with living tissue
Gregory Fridman,Danil Dobrynin,Sameer Kalghatgi,Ari D. Brooks,Gary Friedman,Alexander Fridman +5 more
TL;DR: In this article, biochemical and physical mechanisms of plasma interaction with biological materials are discussed, where a surface of a microorganism is used as one of the plasma-generating electrodes is compared with indirect interaction where plasma is generated elsewhere and the plasma treated gas is carried off to a remote location for microorganization treatment.
Journal ArticleDOI
The response of Escherichia coli, Bacillus subtilis, and Burkholderia cepacia WZ1 to oxidative stress of exposure to quinclorac.
Zhenmei Lu,Hang Min,Ying Xia +2 more
TL;DR: Native polyacrylamide gel electrophoresis and activity staining of SOD revealed that quinclorac had effects on isoforms of E.coli and B. subtilis, and on the staining intensities of theisoforms of B. cepacia WZ1, showing a striking dose–response relationship, which can, therefore, be used as an available bioindicator for quinClorac pollution.
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.