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192d
From Proteopedia
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RECOMBINATION-LIKE STRUCTURE OF D(CCGCGG)
Overview
We have solved the single crystal X-ray structure of the synthetic DNA, hexamer d(CCGCGG). The central alternating tetramer forms a Z-DNA duplex., The initial cytosine of each strand of the duplex swings out and forms a, Watson-Crick base-pair with the terminal guanine of a symmetry-related, molecule. Thus, two symmetry-related DNA molecules form a twin with, intermolecular base-pairs at both ends. Such a twin is additionally, stabilized by a sodium ion located on a dyad axis between two DNA, duplexes. The total structure has recombination-like features. It also, provides a model for B/Z junctions. The crystal used in this study belongs, to space group C222(1) with a = 34.33 A, b = 44.04 A and c = 38.27 A. The, structure was solved by molecular replacement using partial models, and, refined by molecular dynamics simulated annealing and positional, treatment. The refinement has been concluded with an R-factor of 18.5% for, 2377 reflections with F > or = 2 sigma (F) in the resolution region 8.0 to, 1.92 A. The asymmetric unit contains two strands of d(CCGCGG) and 38 water, molecules.
About this Structure
192D is a Protein complex structure of sequences from [1] with NA as ligand. Full crystallographic information is available from OCA.
Reference
Recombination-like structure of d(CCGCGG)., Malinina L, Urpi L, Salas X, Huynh-Dinh T, Subirana JA, J Mol Biol. 1994 Oct 28;243(3):484-93. PMID:7966274
Page seeded by OCA on Sat Nov 24 22:11:46 2007
