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Updated: Jul 24, 2026

Iterative Optimization of DNA Duplexes for Crystallization of SeqA-DNA Complexes
Published on: November 1, 2012
Crystallization and preliminary crystallographic study of triple-helical DNA
1Laboratory of Molecular Biology, NIDDK, National Institutes of Health, Bethesda, MD 20892, USA.
Abstract:
Single crystals of d(CTCCT(S)CCGCGCG).d(CGCGCGGAG) have been grown by the vapor-diffusion method using 2-methyl-2,4-pentanediol as a precipitant. The crystals are tetragonal, space group P4(2), with unit-cell parameters a = b = 53.8, c = 43.1 A, and diffract to 1.8 A resolution at a synchrotron X-ray beamline. In the crystal, the asymmetric unit contains one copy of the construct. The two halves of the structure are related by non-crystallographic twofold symmetry. These observations are consistent with the conclusion that the sequences of the 12-mer and 9-mer oligonucleotides form a duplex DNA at one end and a triplex DNA at the other end.
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