Linked Life Data

4028287

Source:http://linkedlifedata.com/resource/pubmed/id/4028287

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1985-10-2
pubmed:abstractText
[14C]Benzidine is rapidly oxidized by a peroxidase/H2O2 system to products which bind irreversibly to DNA. The presence of exogenous DNA also prevented benzidine polymerization to 'benzidine brown' and azobenzidine. Two molar equivalents of H2O2 were required to oxidize the benzidine and achieve maximal DNA binding. Furthermore, 95% of the benzidine was trapped and 36 nmol benzidine was bound per mg DNA. Polyriboguanylic acid was as effective as DNA in binding benzidine, but polyriboadenylic acid, polyribouridylic acid and polyribocytidylic acid were much less effective. Binding of [14C]benzidine correlated well with the absorbance at 295 nm and 390 nm of the modified DNA or various synthetic homopolymers of ribonucleotides isolated from the reaction mixture. The peroxidase/H2O2 system also catalyzed the binding of dichlorobenzidine, o-tolidine and o-dianisidine to DNA but 3,5,3',5'-tetramethylbenzidine, a non-carcinogen, did not bind. The binding could be prevented by various biological hydrogen donors, thiols, or phenolic antioxidants. The mechanisms for DNA protection were investigated; the oxidized benzidine species involved in binding can be reduced with ascorbate, NADPH, or thiols, and trapped by thiols or phenolic antioxidants to form conjugates or adducts.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0009-2797
pubmed:author
pubmed:issnType
Print
pubmed:volume
54
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
143-58
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Peroxidase-catalyzed benzidine binding to DNA and other macromolecules.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't