title: Models of triple-stranded polynucleotides with optimised stereochemistry.
abstract: Detailed models are presented for the triple-stranded polynucleotide helices of poly (U)-poly (A)-poly (U) (two forms), poly (U)-poly d (A) -poly (U), poly d(C)-poly d(I)-poly d(C), poly d(T)-polyd(A)-poly d(T) and poly (I)-poly (A)-poly (I). The models were genrated using a computerized, linked-atom procedure which preserves standard bond lengths, bond anglesand sugar ring conformations, constrains the helices to have the pitches and symmetries observed in X-ray diffraction experiments, and optimises the non-bonded interatomic contacts including hydrogen bonds. The possible biological sigificance of such complexes is discussed.
mesh_terms: D003201:Computers; D004247:DNA; D006860:Hydrogen Bonding; D008958:Models, Molecular; D008961:Models, Structural; D009690:Nucleic Acid Conformation; D012313:RNA
chemical_list: D012313:RNA; D004247:DNA