New 13C-detected experiments for the assignment of intrinsically disordered proteins

NMR assignment of intrinsically disordered proteins (IDPs) by conventional HN-detected methods is hampered by the small dispersion of the amide protons chemical shifts and exchange broadening of amide proton signals. Therefore several alternative assignment strategies have been proposed in the last years. Attempting to seize that dispersion of 13C′ and 15N chemical shifts holds even in IDPs, we recently proposed two 13C-detected experiments to directly correlate the chemical shifts of two consecutive 13C′-15N groups in proteins, i.e. without mediation of other nuclei. Main drawback of these experiments is the interruption of the connection at prolines. Here we present new 13C-detected experiments to correlate consecutive 13C′-15N groups in IDPs, hacacoNcaNCO and hacaCOncaNCO, that overcome this limitation. Moreover, the experiments provide recognition of glycine residues, thereby facilitating the assignment process. © 2014 Springer Science+Business Media.Peer Reviewe