1s23
From Proteopedia
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Crystal Structure Analysis of the B-DNA Decamer CGCAATTGCG
Overview
The deoxyoligonucleotide d(CGCAATTGCG) has previously been crystallized in, four different space groups. The crystals diffract to moderate resolution, (2.3-2.9 A). Here, a fifth crystal form that diffracts to higher, resolution (1.6 A) is presented which was obtained thanks to the use of, Co2+ and cryogenic temperatures. The availability of five different, crystal structures allows a thorough analysis of the conformational, variability of this DNA sequence. It is concluded that the central hexamer, sequence CAATTG has a practically constant conformation under all, conditions, whilst the terminal base pairs at both ends vary considerably, as a result of differing interactions in the crystals. The new crystal, structure presented here is stabilized by guanine-Co2+-guanine, interactions and the formation of C1+ -G8.C3 triplexes between, neighbouring duplexes. As a result of the higher resolution of the crystal, structure, a more regular structure was obtained and a clear definition of, the spine of hydration was observed which was not visible in the four, previous structures.
About this Structure
1S23 is a Protein complex structure of sequences from [1] with CO as ligand. Full crystallographic information is available from OCA.
Reference
DNA variability in five crystal structures of d(CGCAATTGCG)., Valls N, Wright G, Steiner RA, Murshudov GN, Subirana JA, Acta Crystallogr D Biol Crystallogr. 2004 Apr;60(Pt 4):680-5. Epub 2004, Mar 23. PMID:15039556
Page seeded by OCA on Sat Nov 24 23:43:39 2007
