title: Crystal structure of rGd(CGCGCG): a Z-DNA hexamer duplex with a 5'-(rG) overhang.
abstract: The crystal structure of the heptamer rGd(CGCGCG) has been determined at 1.54 A resolution with R(work) and R(free) of 0.191 and 0.235, respectively. The crystal belongs to space group P2(1)2(1)2(1), with unit-cell parameters a = 17.96, b = 31.47, c = 44.73 A and two independent strands in the asymmetric unit. The chimera forms a Z-DNA hexamer duplex d(CGCGCG)(2), with the 5'-overhang rG invisible in the density. The replacement of rG in the 5' terminus of d(GCGCGCG) changes the reverse Hoogsteen G.G base pairing of the 5'-overhang dG (Pan et al., 1997). However, the replacement does not change the helix from Z-form to A-form or the water-structure motifs in the Z-DNA double-helical structure.
authors.affiliation: Departments of Chemistry and Biochemistry, 200 Johnston Laboratory, 176 West 19th Avenue, Columbus, Ohio 43210-1002, USA.
authors.forename: Baocheng
authors.initials: B
authors.lastname: Pan
authors.forename: Muttaiya
authors.initials: M
authors.lastname: Sundaralingam
mesh_terms: D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D009841:Oligonucleotides / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D009841:Oligonucleotides