A solid-state NMR study of the structure and molecular mobility of α-keratin

Abstract

A solid-state NMR study of an α-keratin sourced from equine hoof has revealed a strong dependence of molecular conformation and molecular dynamics on the degree of hydration of the material. 13C cross-polarization, magic-angle spinning experiments were used in conjunction with two-dimensional 13C-1H WISE and 2H NMR to provide a detailed examination of these factors. In particular, dehydration results in a much more rigid and ordered structure, with a loss of α-helical components in the structure and breaking of cysteine disulfide linkages. These results have clear implications for our understanding of the material properties of equine hoof wall.