TROSY-based HNCO pulse sequences for the measurement of 1HN-15N, 15N-13CO, 1HN-13CO, 13CO-13Cα and 1HN-13Cα dipolar couplings in 15N, 13C, 2H-labeled proteins

HNCO-based 3D pulse schemes are presented for measuring 1HN-15N,15N-13CO, 1HN-13CO,13CO-13Cα and 1HN-13Cα dipolar couplings in 15N,13C,2-labeled proteins. The experiments are based on recently developed TROSY methodology for improving spectral resolution and sensitivity. Data sets recorded on a complex of Val, Leu, Ile (δ1 only) methyl protonated 15N,13C,2H-labeled maltose binding protein and β-cyclodextrin as well as 15N,13C,2H-labeled human carbonic anhydrase II demonstrate that precise dipolar couplings can be obtained on proteins in the 30–40 kDa molecular weight range. These couplings will serve as powerful restraints for obtaining global folds of highly deuterated proteins.