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208d
From Proteopedia
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| , resolution 2.050Å | |||||||
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| Ligands: | , , , , | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
HIGH-RESOLUTION STRUCTURE OF A DNA HELIX FORMING (C.G)*G BASE TRIPLETS
Overview
Triple helices result from interaction between single- and double-stranded nucleic acids. Their formation is a possible mechanism for recombination of homologous gene sequences in nature and provides, inter alia, a basis for artificial control of gene activity. Triple-helix motifs have been extensively studied by a variety of techniques, but few high-resolution structural data are available. The only triplet structures characterized so far by X-ray diffraction were in protein-DNA complexes studied at about 3 A resolution. We report here the X-ray analysis of a DNA nonamer, d(GCGAATTCG), to a resolution of 2.05 A, in which the extended crystal structure contains (C.G)*G triplets as a fragment of triple helix. The guanosine-containing chains are in a parallel orientation. This arrangement is a necessary feature of models for homologous recombination which results ultimately in replacement of one length of DNA by another of similar sequence. The present-structure agrees with many published predictions of triplex organization, and provides an accurate representation of an element that allows sequence-specific association between single- and double-stranded nucleic acids.
About this Structure
208D is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
High-resolution structure of a DNA helix forming (C.G)*G base triplets., Van Meervelt L, Vlieghe D, Dautant A, Gallois B, Precigoux G, Kennard O, Nature. 1995 Apr 20;374(6524):742-4. PMID:7715732
Page seeded by OCA on Mon Mar 31 01:44:06 2008
