Nucleotide torsional flexibility in solution and the use of the lanthanides as nuclear-magnetic-resonance conformation probes. The case of adenosine 5'-monophosphate.

In this article the single family of conformations of adenosine 5'-monophosphate (5'AMP) in aqueous solution previously obtained using the lanthanide ions as nuclear magnetic resonance (NMR) probes is shown to disagree with the conformational data available from independent NMR methods, such as coupling constant and nuclear Overhauser enhancement analysis. The original lanthanide experimental data is reinterpreted assuming the contribution of different conformers to the observed magnetic perturbations. The average conformation obtained for 5'AMP agrees quite satisfactorily with the other independent conformational information.