The amide proton NMR chemical shift and hydrogen-bonded structure of peptides and polypeptides in the solid state as studied by high-frequency solid-state [formula omitted] NMR

Abstract

High-resolution 1 H NMR spectra of glycine (Gly)-containing peptides and polypeptides in the solid state were measured at 800 MHz and at high-speed magic-angle-spinning (MAS) of 30 kHz to elucidate the relationship between the hydrogen-bond length and 1 H NMR chemical shift to add to our previous experimental and theoretical findings that there is a relationship between the hydrogen-bond length and 13 C , 15 N and 17 O chemical shifts of various kinds of amino acid residues of peptides and polypeptides in the solid state. From these experimental results, it is found that the 1 H chemical shifts of Gly amide protons of Gly-containing peptides and polypeptides, for which the hydrogen-bond length between the nitrogen and oxygen atoms ( R N…O) have already been determined by X-ray diffraction, move downfield with a decrease in R N…O. Theoretical calculations qualitatively explain these experimental results.