Direct correlation of consecutive C'-N groups in proteins: a method for the assignment of intrinsically disordered proteins.

Two novel 3D (13)C-detected experiments, hNcocaNCO and hnCOcaNCO, are proposed to facilitate the resonance assignment of intrinsically disordered proteins. The experiments correlate the (15)N and (13)C' chemical shifts of two consecutive amide moieties without involving other nuclei, thus taking advantage of the good dispersion shown by the (15)N-(13)C' correlations, even for proteins that lack a well defined tertiary structure. The new pulse sequences were successfully tested using Nupr1, an intrinsically disordered protein of 93 residues.