Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1996-7-25
pubmed:abstractText
When DNA is bent around a protein, it must distort. The distortion occurs by changes in the conformation of successive dinucleotide steps. Bending does not necessarily occur uniformly: some steps might remain particularly rigid, i.e. they might deform relatively little, while others might take more than their proportional share of deformation. We investigate here the deformational capacity of specific dinucleotide steps by examining a database of crystallized oligomers. Dividing the steps into ten types by sequence (AA( = TT), AC( = GT), AG( = CT), AT, CA( = TG), CG, GA( = TC), GC, GG( = CC) and TA), we find that some step types are practically rigid, while others have considerable internal mobility or conformational flexibility. Now in general base-pairs are not planar, but have Propeller-Twist. We find a clear empirical correlation between the level of Propeller-Twist in the base-pairs and the flexibility of the dinucleotide step which they constitute. Propeller-Twist in the base-pairs makes stacking into a dinucleotide step more awkward than in plane base-pairs. In particular, it provides a stereochemical "locking" effect which can make steps with highly Propeller-Twisted base-pairs rigid. Although the origins of Propeller-Twist are not yet clearly understood, this result provides a key to understanding the flexibility of DNA in bending around proteins.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0022-2836
pubmed:author
pubmed:issnType
Print
pubmed:day
31
pubmed:volume
259
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
95-103
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Propeller-twisting of base-pairs and the conformational mobility of dinucleotide steps in DNA.
pubmed:affiliation
Department of Engineering, University of Cambridge, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't