Two-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.
David Lyndon Emsley, Yu Rao, Moreno Lelli, Pierrick Berruyer, Gabriele Stevanato, Snaedis Björgvinsdóttir, Andrea Bertarello
Andrea Capozzi, Arthur César Pinon
David Lyndon Emsley, Marinella Mazzanti, Anne-Sophie Chauvin, Dominik Józef Kubicki, Gabriele Stevanato, Georges Guévork Jean-Jacques Menzildjian