Proceedings of the National Academy of Sciences · 1980 · 180 citations · 6 references
Life SciencesBiochemistryMolecular BiologyCrystal StructureStructural BiochemistryStructural BiologyBase StackingCrystal SystemsCrystallographyDna StructureMacromolecular AssemblySecondary StructureBase Pair StackingDna Double HelixDna Secondary StructureHexagonal Unit CellsStacking In Dna DuplexesTetragonal Unit CellsX-ray Diffraction Analysis
The structure of the tetramer d(CpGpCpG) has been solved by x-ray analysis in two different crystal forms with and without spermine cations. The molecules crystallize in hexagonal unit cells and they form a left-handed double helix of Z-DNA similar to that previously reported for the hexamer d(CpGpCpGpCpG). In the crystal lattice the molecules stack together to form a virtually continuous left-handed double helix in which every fourth phosphate group is missing. The stacking of bases upon each other is similar to that seen in the hexamer. However, the base pairs have a slightly different orientation in that the cytosine residues are slightly removed from the axis of the molecule compared to the position they occupy in the hexamer. The structures are similar in two crystal forms with and without spermine cations.
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Molecular structure of a left-handed double helical DNA fragment at atomic resolution
Andrew H.‐J. Wang, Gary J. Quigley, Francis J. Kolpak et al. · Nature · 1979 · 2.1K citations
Double Helix at Atomic Resolution
John M. Rosenberg, Nadrian C. Seeman, Jung Ja Park Kim et al. · Nature · 1973 · 187 citations