Complete assignments of magnetic resonances of ribonuclease H from Escherichia coli by double- and triple-resonance 2D and 3D NMR spectroscopies

The assignment of magnetic resonances of large proteins and the determination of their tertiary structures is done using double- and triple-resonance 2D and 3D NMR experiments. The tertiary structure of the protein molecule helps in analyzing the chemical shifts. Larger secondary shifts for the C alpha, C beta and C' nuclei were observed among the 3C chemical shifts. All types of 1H, 15N and 13C nuclei detectable by NMR were studied. The chemical shifts were found to be a good measure of local structures and charged states by their secondary shifts.