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

A triple-resonance pulse scheme is described which records(15)N, NH correlations of residues that immediately follow amethyl-containing amino acid. The experiment makes use of a(15)N, (13)C and fractionally deuterated proteinsample and selects for CH(2)D methyl types. The experiment isthus useful in the early stages of the sequential assignment process as wellas for the confirmation of backbone (15)N, NH chemical shiftassignments at later stages of data analysis. A simple modification of thesequence also allows the measurement of methyl side-chain dynamics. This isparticularly useful for studying side-chain dynamic properties in partiallyunfolded and unfolded proteins where the resolution of aliphatic carbon andproton chemical shifts is limited compared to that of amide nitrogens.