NMR studies on solution structure of single-stranded oligonucleotides causing line broadening.

Abstract

Unusual line broadening of 1H-NMR lines attributable to the proton (8H) of guanine residues was observed for all tetradeoxyoligonucleotides tested here which have a specific base sequence of dGXXG (X = A or T). For the same samples, line broadening was also obtained in the 31P-NMR spectra. These broadened signals did not become sharp up to 60 degrees C. This unusual spectral phenomenon has been attributed by 2D-NMR and differential NOE to the compact solution structure of the oligonucleotides.