Side-chain conformation and dynamics in a solid peptide: CP-MAS NMR study of valine rotamers and methyl-group relaxation in fully 13C-labelled antamanide
Straus, Suzana ; Bremi, Tobias ; Ernst, Richard
In: Journal of Biomolecular NMR, 1997, vol. 10, no. 2, p. 119-128
Ajouter à la liste personnelle- Summary
- The effect of the crystal lattice on the side-chain conformation andside-chain dynamics in peptides is investigated by solid-state NMR, using thecyclic decapeptide antamanide as an example. The study takes advantage of the13C assignment of the backbone and side chains based on theresolution-enhanced 2D spin-diffusion spectra by heteronuclear and homonucleardecoupling. The spectra even allow for a stereospecific assignment of theγ-carbons of the valine residue. It is found that the valine side chaincoexists in two static rotamer conformations which have not been observed byX-ray crystallography. In addition, remarkable effects of the crystal packingon the methyl-group rotation frequency are found from 13Crelaxation measurements