1H-filtered correlation experiments for assignment and determination of coupling constants in backbone labelled proteins.

The implementation of [13Calpha,13C',15N,2Halpha] labelled amino acids into proteins allows the acquisition of high resolution triple resonance experiments. We present for the first time resonance assignments facilitated by this new labelling strategy. The absence of 1JCalpha,Cbeta couplings enables us to measure 1JCalpha,C' scalar and 1DCalpha,C' residual dipolar coupling constants using modified HNCA experiments which do not suffer from sensitivity losses characteristic for 13C constant time experiments.