Specific N-15,NH correlations for residues in N-15,C-13 and fractionally deuterated proteins that immediately follow methyl-containing amino acids

A triple-resonance pulse scheme is described which records N-15, NH correlations of residues that immediately follow a methyl-containing amino acid. The experiment makes use of a N-15, C-13 and fractionally deuterated protein sample and selects for CH2D methyl types. The experiment is thus useful in the early stages of the sequential assignment process as well as for the confirmation of backbone N-15, NH chemical shift assignments at later stages of data analysis. A simple modification of the sequence also allows the measurement of methyl side-chain dynamics. This is particularly useful for studying side-chain dynamic properties in partially unfolded and unfolded proteins where the resolution of aliphatic carbon and proton chemical shifts is limited compared to that of amide nitrogens.