Linked Life Data

1457732

Source:http://linkedlifedata.com/resource/pubmed/id/1457732

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1993-1-14
pubmed:abstractText
The left-handed Z-DNA structure of an araC-containing (where araC stands for arabinosylcytosine) hexamer, (araC-dG)3, has been solved by x-ray diffraction analysis at 1.3 A resolution. This hexamer was crystallized in the hexagonal P6(5)22 (a = b = 17.96 A, c = 43.22 A) space group in which the hexamers have statistically disordered packing arrangement along the 6(5) screw axis, yet the crystals diffract x-rays to high resolution. Its structure has been refined by the constrained least square refinement to a final R factor of 0.287 using 737 [> 3.0 sigma(F)] observed reflections. The asymmetric unit of the unit cell contains only a dinucleotide, 5'-p (araC)p(dG). The overall conformation resembles that of the canonical Z-DNA, but with some differences in details. The O2' hydroxyl groups of the araC residues form intramolecular hydrogen bonds with N2 of the 5'-guanine residues. In the deep groove of Z-DNA, these hydroxy groups replace the bridging water molecules that stabilize the guanine in the syn conformation. The results reinforce the earlier observation made by the structural analysis of another hexamer, d(CG[araC]GCG), with a mono-substitution of araC [M.-K. Teng, Y.-C. Liaw, G. A. van der Marel, J. H. van Boom, and A. H.-J. Wang (1989) Biochemistry, vol. 28, pp. 4923-4928]. These two structures show that araC residue can be incorporated readily into the Z structure and probably facilitates the B to Z transition, as supported by uv absorption spectroscopic studies in a number of araC-containing oligonucleotides. The potential biological roles of the araC-modified Z-DNA are discussed.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0006-3525
pubmed:author
pubmed:issnType
Print
pubmed:volume
32
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1559-69
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Conformational perturbation of the anticancer nucleotide arabinosylcytosine on Z-DNA: molecular structure of (araC-dG)3 at 1.3 A resolution.
pubmed:affiliation
Division of Biophysics, University of Illinois, Champaign, Urbana 61801.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.