13C selective polarization and spin diffusion in a lipid bilayer-bound polypeptide by solid-state NMR

While N-15 solid-state NMR has proven to be very advantageous for the development of structural biological methods, C-13 spectroscopy has increased sensitivity and spectral dispersion. However, large natural abundance signals and homonuclear dipolar interactions pose significant problems. Here we have used a pair of C-13-labeled sites in a lipid-solubilized polypeptide to show the selective polarization can be used in combination with spin diffusion to achieve simplified spectra. Both unoriented and oriented samples have been used, with the latter providing a well-resolved homonuclear dipolar splitting. (C) 1999 Academic Press.