Sequential assignment of amide resonances in proteins and peptides can conveniently be derived from twodimensional inter-residue 15Ni –1HN(i−1) and intra-residue 15Ni –1HNi correlation spectra. The inter-residue 15Ni –1HN(i−1)correlation spectrum is generated by recording the 15Ni frequency evolution indirectly and subsequently transferring the magnetization to 1HN(i−1) of the preceding residue for direct detection. The flow of coherence is established by the (H)N(COCAHA)-TOCSY pulse sequence. Following the path from intra-residue correlation via inter-residue correlation to the next intra-residue correlation results in sequential assignment in two dimensions. This kind of assignment protocol is most amenable to re-establishing sequential assignments of target proteins perturbed by binding of ligands or alternatively signals of peptide ligands can be traced in studies of structure–function relationships by NMR.
Permi, P., & Annila, A. (2001). Sequential resonance assignment from two-dimensional inter- and intra-residue 15N-1H correlation spectra. Magnetic Resonance in Chemistry, 39(4), 179-181. https://doi.org/10.1002/mrc.821