Linked Life Data

10207127

Source:http://linkedlifedata.com/resource/pubmed/id/10207127

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1999-5-11
pubmed:abstractText
The ability of relatively stable Cr(V) and Cr(IV) complexes with 2-hydroxycarboxylato ligands [2-ethyl-2-hydroxybutanoate(2-) = ehba; (1R,3R,4R,5R)-1,3,4,5-tetrahydroxycyclohexanecarboxylate(2-) = quinate = qa] to induce single-strand breaks in plasmid DNA has been studied under a wide range of reaction conditions. The Cr(V) complex, Na[CrVO(ehba)2], causes substantial DNA cleavage at pH 4.0-8.0 [[Cr(V)]0 = 0.010-0.75 mM, phosphate buffer, and 37 degrees C]. The DNA cleavage is inhibited by the presence of excess ligand, by exclusion of O2, or by addition of organic compounds, such as alcohols, carboxylic acids, or DMSO, but it is not affected by traces of catalytic metals [Fe(III) or Cu(II)] or by addition of catalase. The Cr(IV)-qa complexes, unlike the Cr(V) complexes, are able to cleave DNA in the presence of the ligand in a large excess [[Cr(IV)]0 = 0.50 mM, [qa] = 20-100 mM, pH 3.5-6.0, and 37 degrees C]. This is the first direct evidence for DNA cleavage induced by well-characterized Cr(IV) complexes. The proposed mechanism for DNA cleavage includes the following: (i) partial aquation of the bis-chelated Cr(V) and -(IV) complexes with the formation of reactive monochelated forms, (ii) binding of the Cr(V) and -(IV) monochelates to the phosphate backbone of DNA, (iii) one- or two-electron oxidations at the deoxyribose moieties of DNA by Cr(V) and -(IV), and (iv) cleavage of the resulting DNA radicals or cations with or without participation of O2. The patterns of DNA damage by Cr(V) and -(IV) can include strand breaks, generation of abasic sites, and the formation of Cr(III)-DNA complexes.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0893-228X
pubmed:author
pubmed:issnType
Print
pubmed:volume
12
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
371-81
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
In vitro plasmid DNA cleavage by chromium(V) and -(IV) 2-hydroxycarboxylato complexes.
pubmed:affiliation
School of Chemistry, University of Sydney, Sydney 2006 NSW, Australia.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't