Linked Life Data

8110736

Source:http://linkedlifedata.com/resource/pubmed/id/8110736

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1994-3-28
pubmed:abstractText
GA mismatches in DNA have drawn attention because of their special repair mechanisms, stability, and variety of conformations. A symmetric 10-base oligodeoxyribonucleotide duplex, d(CCATGAATGG)2, containing two GA mismatches has been investigated by one- and two-dimensional multinuclear NMR and molecular refinement procedures to ascertain the conformational details of the 5'-pyrimidine-GA-purine-3' sequence. A molecular model established from the NMR results has a B-type right-handed helix with each of the bases retaining the normal anti-glycosidic torsional angles. Type I mismatched base pairs have GNH2-AN7 and GN3-ANH2 (edge-to-edge) hydrogen bonds, while type II base pairs have GN1H-AN1 and GO6-ANH2 (face-to-face) bonds. The conformation at the GA mismatch site has type I GA base pairs and an unusual cross-strand stacking of the adjacent G5 and A6 bases, which causes significant overwinding of the helix at the mismatch site. Unusual shifts of the 31P resonances suggest that the phosphate linkage between G5 and A6 is no longer in the low-energy BI conformation. One-dimensional imino and phosphorus NMR studies were carried out on a number of DNA sequences containing adjacent 5'-GA-3' mismatched base pairs to investigate the sequence dependence of the conformations and base-pairing types. Type I and type II conformations have very different imino proton and 31P NMR spectral patterns that can be used to classify any sequence with adjacent GA mismatches by base-pairing and conformational type. The NMR results indicate that the conformation selected is dictated completely by the flanking sequence: 5'-pyrimidine-GA-purine-3' sequences adopt the type I conformation, while 5'-purine-GA-pyrimidine-3' sequences have the type II conformation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
8
pubmed:volume
33
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1053-62
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Solution structure of a GA mismatch DNA sequence, d(CCATGAATGG)2, determined by 2D NMR and structural refinement methods.
pubmed:affiliation
Department of Chemistry, Georgia State University, Atlanta 30303.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.