Hyperpolarized water produced by dissolution dynamic nuclear polarization (dDNP) has recently been shown to enable the detection of hyperpolarized spectra of proteins with up to 300-fold improvement in signal amplitudes. With this dDNP approach, novel insights can be gained into solvent accessible surfaces, ligand interactions, and complex protein geometries. Examples of applications to host-ligand systems including peptides and folded as well as intrinsically disordered proteins (IDPs) have demonstrated the broad applicability of the hyperpolarized water approach. [1-5]
In this contribution, we present recent efforts to combine dDNP with real-time NMR, aimed at tracking protein-ligand binding events and protein-solvent interactions at a sub-Hertz sampling rate. Two applications will be presented: (1) The use of hyperpolarized water to examine the kinetics underlying protein-ligand interactions. Here, non-equilibrium dynamics in the osteopontin-heparin host-ligand system were monitored in a dDNP experiment by simultaneous mixing of the protein with the ligand and hyperpolarized water. (2) A proof-of-concept for real-time protein dDNP at residue-resolution at hand of Ubiquitin in hyperpolarized water by a statistical analysis of time-series of 1D dDNP spectra.
1. P. Kaderavek, F. Ferrage, G. Bodenhausen and D. Kurzbach, Chem. Eur. J., 2018, 24, 13418-13423.
2. O. Szekely, G. L. Olsen, I. C. Felli and L. Frydman, Anal Chem, 2018, 90, 10, 6169-6177.
3. D. Kurzbach, E. Canet, A. G. Flamm, A. Jhajharia, E. M. Weber, R. Konrat and G. Bodenhausen, Angew Chem Int Ed Engl, 2017, 56, 389-392.
4. G. Olsen, E. Markhasin, O. Szekely, C. Bretschneider and L. Frydman, J Magn Reson, 2016, 264, 49-58.
5. G. L. Olsen, O. Szekely, B. Mateos, P. Kadeřávek, F. Ferrage, R. Konrat, R. Pierattelli, I. C. Felli, G. Bodenhausen, D. Kurzbach and L. Frydman, 2019, in preparation.