Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
50
pubmed:dateCreated
2000-1-19
pubmed:abstractText
We have examined the DNA damage produced by reaction of peroxyl radicals with human fibroblast DNA. DNA damage consisted of both strand breaks and base modifications. The extent of strand breaks and base modifications induced as a function of peroxyl radical concentration was determined by quantitation of fragment size distributions using denaturing glyoxal-agarose gel electrophoresis. Both strand breaks and base modifications increased in a log linear fashion with respect to peroxyl radical concentration. Oxidative base modifications were observed to occur to a greater extent than strand breaks at every concentration measured. The sequence-specific distribution of peroxyl radical induced base damage was mapped for 803 nucleotide positions using the method of ligation mediated PCR. A total of 87% of all guanine positions in the examined sequences was found to be significantly oxidized. The order of reactivity of DNA bases toward oxidation by peroxyl radicals was found to be G >> C > T. Adenine is essentially unreactive. The yield of oxidative base modifications at guanines and cytosines by peroxyl radicals depends on the exact specification of 5' and 3' flanking bases in a polarity dependent manner. Every guanine in the 5'XGC3' motif was found to be oxidized, where X is any 5' neighbor. In contrast, 5' and 3' purine flanks drastically reduced the extent of peroxyl radical G oxidation. The pattern of base modification and the influence of nearest neighbors differs substantially from that previously reported for hydrogen peroxide damage mediated by low valent transition metal ions for the identical DNA sequences.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
14
pubmed:volume
38
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
16578-88
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:10600120-3' Untranslated Regions, pubmed-meshheading:10600120-5' Untranslated Regions, pubmed-meshheading:10600120-Base Sequence, pubmed-meshheading:10600120-Cells, Cultured, pubmed-meshheading:10600120-DNA, pubmed-meshheading:10600120-DNA Damage, pubmed-meshheading:10600120-DNA Footprinting, pubmed-meshheading:10600120-DNA Ligases, pubmed-meshheading:10600120-Exons, pubmed-meshheading:10600120-Fibroblasts, pubmed-meshheading:10600120-Free Radicals, pubmed-meshheading:10600120-Genes, p53, pubmed-meshheading:10600120-Guanine, pubmed-meshheading:10600120-Humans, pubmed-meshheading:10600120-Male, pubmed-meshheading:10600120-Oxidation-Reduction, pubmed-meshheading:10600120-Peroxides, pubmed-meshheading:10600120-Phosphoglycerate Kinase, pubmed-meshheading:10600120-Polymerase Chain Reaction
pubmed:year
1999
pubmed:articleTitle
Mapping of peroxyl radical induced damage on genomic DNA.
pubmed:affiliation
Division of Biology, Beckman Research Institute of the City of Hope, Duarte, California 91010, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.