Determining hydrogen-bond interactions in spider silk with 1H–13C HETCOR fast MAS solid-state NMR and DFT proton chemical shift calculations

Abstract

Two-dimensional (2D) ¹H–¹³C heteronuclear correlation (HETCOR) solid-state NMR spectra collected with fast magic angle spinning (MAS) are used in conjunction with density functional theory (DFT) proton chemical shift calculations to determine the hydrogen-bonding strength for ordered β-sheet and disordered 3₁₀-helical structures in spider dragline silk. The hydrogen-bond strength is determined to be identical for both structures in spider silk with a 1.83–1.84 Å NH⋯OC hydrogen-bond distance.