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)-poly d(A)-poly d(T) and poly(I)-poly(A)-poly(I). The models were generated using a computerized, linked-atom procedure which preserves standard bond lengths, bond angles and 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 significance of such complexes is discussed. © Information Retrieval Limited.