Cereal Chem 59:240 - 245.  |  VIEW ARTICLE
Solid-State, Cross-Polarization Magic-Angle Spinning Carbon-13 Nuclear Magnetic Resonance and Biochemical Characterization of Wheat Proteins.

J. D. Schofield and I. C. Baianu. Copyright 1982 by the American Association of Cereal Chemists, Inc. 

Gluten and glutenin-enriched and gliadin-enriched subfractions of gluten, prepared by 1M urea extraction, were examined by high-resolution, cross-polarization magic-angle spinning carbon-13 nuclear magnetic resonance (NMR) spectroscopy in the solid state to investigate the applicability of this technique in the physical characterization of gluten proteins. These fractions were also characterized biochemically to aid interpretation of the NMR data. An outstanding feature of the NMR spectra was that the glutenin-enriched fraction gave sharp resonances corresponding to aliphatic and aromatic amino acid side chains, whereas the gliadin-enriched fraction gave broad peaks in these regions. This suggests that the polypeptides in the gliadin-enriched fraction are much more tightly folded than those in the glutenin-enriched fraction and that, in the former, a much greater level of interaction exists among the hydrophobic side chains than in the latter. This implies that hydrophobic interactions may be less important in glutenin quaternary structure than some current models would suggest. The finding that a weighted summation of the spectra for the gliadin- enriched and the glutenin-enriched fractions cannot give a spectrum equivalent to that for the parent gluten suggests, however, that hydrophobic interactions between glutenins and gliadins may be important in the gluten complex.