title: Crystallization and preliminary crystallographic study of triple-helical DNA.
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.
authors.affiliation: Laboratory of Molecular Biology, NIDDK, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: Z J
authors.initials: ZJ
authors.lastname: Han
authors.forename: S
authors.initials: S
authors.lastname: Rhee
authors.forename: K
authors.initials: K
authors.lastname: Liu
authors.forename: H T
authors.initials: HT
authors.lastname: Miles
authors.forename: D R
authors.initials: DR
authors.lastname: Davies
mesh_terms: D001483:Base Sequence; D003460:Crystallization; D018360:Crystallography, X-Ray; D004247:DNA / Q000737:chemistry* / Q000302:isolation & purification*; D009690:Nucleic Acid Conformation; D009838:Oligodeoxyribonucleotides / Q000737:chemistry* / Q000302:isolation & purification*
chemical_list: D009838:Oligodeoxyribonucleotides; D004247:DNA