Publication Date:
1988-04-29
Description:
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.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Imlay, J A -- Chin, S M -- Linn, S -- GM19020/GM/NIGMS NIH HHS/ -- P30ES01896/ES/NIEHS NIH HHS/ -- New York, N.Y. -- Science. 1988 Apr 29;240(4852):640-2.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biochemistry, University of California, Berkeley 94720.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/2834821" target="_blank"〉PubMed〈/a〉
Keywords:
Bacteriophage lambda
;
Chemical Phenomena
;
Chemistry
;
*DNA Damage
;
DNA Repair
;
DNA, Bacterial/*drug effects
;
Escherichia coli/drug effects/*genetics
;
Ferrous Compounds
;
Free Radicals
;
Hydrogen Peroxide/administration & dosage/*pharmacology
;
Hydrogen-Ion Concentration
;
Hydroxides
;
Hydroxyl Radical
;
Oxidation-Reduction
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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