High-Resolution NMR of Folded Proteins in Hyperpolarized Physiological Solvents

International audience; Hyperpolarized 2D exchange spectroscopy (HYPEX) to obtain high‐resolution nuclear magnetic resonance (NMR) spectra of folded proteins under near‐physiological conditions is reported. The technique is based on hyperpolarized water, which is prepared by dissolution dynamic nuclear polarization and mixed in situ in an NMR spectrometer with a protein in a physiological saline buffer at body temperature. Rapid exchange of labile protons with the hyperpolarized solvent, combined with cross‐relaxation effects (NOEs), leads to boosted signal intensities for many amide 1H–15N correlations in the protein ubiquitin. As the introduction of hyperpolarization to the target protein is mediated via the solvent, the method is applicable to a broad spectrum of target molecules.