Linked Life Data

15248767

Source:http://linkedlifedata.com/resource/pubmed/id/15248767

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
28
pubmed:dateCreated
2004-7-13
pubmed:abstractText
We have used the single electron oxidizing agent (SCN)(2)(*)(-) (generated by gamma-irradiation of aqueous thiocyanate) to produce guanyl radicals in plasmid DNA. The stable product(s) formed from these radicals can be detected after conversion with a base excision repair endonuclease to single strand breaks. The yield of enzyme-induced breaks is decreased by the presence during irradiation of indole compounds. Rate constants for the reduction of DNA guanyl radicals by these indoles can be calculated from the concentration dependence of the attenuation in the yield of enzyme sensitive sites. Indoles bearing electron-donating groups (methoxy or methyl) appear to react at the diffusion-controlled rate, but those bearing electron-withdrawing groups (cyano or nitro) are significantly less reactive. At physiological pH values, the reduction of a DNA guanyl radical involves the transfer of a proton as well as an electron. Comparison of the kinetic results with literature thermodynamic data suggests that the source of this proton is the complementary base-paired cytosine.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
20
pubmed:volume
43
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
9098-104
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Repair of oxidative guanine damage in plasmid DNA by indoles involves proton transfer between complementary bases.
pubmed:affiliation
Department of Radiology, University of California at San Diego, 9500 Gilman Drive, La Jolla, California 92093-0610, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't