Site-specific protein methyl deuterium quadrupolar patterns by proton-detected 3D 2H–13C–1H MAS NMR spectroscopy

Abstract

Determination of protein structure and dynamics is key to understand the mechanism of protein action. Perdeuterated proteins have been used to obtain high resolution/sensitivty NMR experiments via proton-detection. These methods utilizes ¹H, ¹³C and ¹⁵N nuclei for chemical shift dispersion or relaxation probes, despite the existing abundant deuterons. However, a high-sensitivity NMR method to utilize deuterons and e.g. determine site-specific deuterium quadrupolar pattern information has been lacking due to technical difficulties associated with deuterium’s large quadrupolar couplings. Here, we present a novel deuterium-excited and proton-detected three-dimensional ²H–¹³C–¹H MAS NMR experiment to utilize deuterons and to obtain site-specific methyl ²H quadrupolar patterns on detuterated proteins for the first time. A high-resolution fingerprint ¹H–¹⁵N HSQC-spectrum is correlated with the anisotropic deuterium quadrupolar tensor in the third dimension. Results from a model perdeuterated protein has been shown.