The measurement of amide nitrogen 14N quadrupolar coupling by two-dimensional 14N/13C correlation experiment is presented with a natural abundant polypeptide. Directly bonded 14N/13C pairs are correlated through J and residual dipolar coupling under magic-angle spinning using a HMQC-type pulse sequence. The 14N quadrupolar coupling is measured from the isotropic second-order quadrupolar shift o...

Information about chemical shift anisotropy is usually difficult to extract from the spectrum of a nonspinning powdered sample because of the usually extensive overlap of the powder patterns from the chemically different sites in the molecule. Several types of experiments have been proposed to facilitate the measurement of chemical shift anisotropy (1-9). All have the common feature that the sa...

The assignment of the aliphatic 1H and 13C resonances of IL-1 beta, a protein of 153 residues and molecular mass 17.4 kDa, is presented by use of a number of novel three-dimensional (3D) heteronuclear NMR experiments which rely on large heteronuclear one-bond J couplings to transfer magnetization and establish through-bond connectivities. These 3D NMR experiments circumvent problems traditional...

Advanced solid-state NMR was employed to investigate differences in chemical structure and heterogeneity between milled wood lignin (MWL) and residual enzyme lignin (REL). Wiley and conventional milled woods were also studied. The advanced NMR techniques included 13C quantitative direct polarization, various spectral-editing techniques, and two-dimensional 1H-13C heteronuclear correlation NMR w...

This paper describes a [15N,1H]/[13C,1H]-TROSY experiment for the simultaneous acquisition of the heteronuclear chemical shift correlations of backbone amide 15N-1H groups, side chain 15N-1H2 groups and aromatic 13C-1H groups in otherwise highly deuterated proteins. The 15N-1H and 13C-1H correlations are extracted from two subspectra of the same data set, thus preventing possible spectral overl...

The comprehensive structure determination of isotopically labeled proteins by solid-state NMR requires sequence-specific assignment of 13C and 15N spectra. We describe several 2D and 3D MAS correlation techniques for resonance assignment and apply them, at 7.0 Tesla, to 13C and 15N labeled ubiquitin to examine the extent of resonance assignments in the solid state. Both interresidue and intrare...