Otting, G.Gruetter, R.Leupin, W.Minganti, C.Ganesh, K. N.Sproat, B. S.Gait, M. J.Wüthrich, K.2012-05-282012-05-282012-05-28198710.1111/j.1432-1033.1987.tb13504.xhttps://infoscience.epfl.ch/handle/20.500.14299/80945Two-dimensional nuclear Overhauser enhancement (NOESY) spectra of labile protons were recorded in H2O solutions of a protein and of a DNA duplex, using a modification of the standard NOESY experiment with all three 90 degree pulses replaced by jump-and-return sequences. For the protein as well as the DNA fragment the strategically important spectral regions could be recorded with good sensitivity and free of artifacts. Using this procedure, sequence-specific assignments were obtained for the imino protons, C2H of adenine, and C4NH2 of cytosine in a 23-base-pair DNA duplex which includes the 17-base-pair OR3 repressor binding site of bacteriophage lambda. Based on comparison with previously published results on the isolated OR3 binding site, these data were used for a study of chain termination effects on the chemical shifts of imino proton resonances of DNA duplexes.text::journal::journal article::research article