Mar 25, 2019

19F Dynamic Nuclear Polarization at Fast Magic Angle Spinning for NMR of HIV-1 Capsid Protein Assemblies #DNPNMR

This is great work showing off the capabilities of DNP to study 19F in biological samples.




Lu, Manman, Mingzhang Wang, Ivan V. Sergeyev, Caitlin M Quinn, Jochem Struppe, Melanie Rosay, Werner Maas, Angela M. Gronenborn, and Tatyana Polenova. “19F Dynamic Nuclear Polarization at Fast Magic Angle Spinning for NMR of HIV-1 Capsid Protein Assemblies.” Journal of the American Chemical Society, March 15, 2019.


We report remarkably high, up to 100-fold, signal enhancements in 19F dynamic nuclear polarization (DNP) magic angle spinning (MAS) spectra at 14.1 T on HIV-1 CA capsid protein assemblies. These enhancements correspond to absolute sensitivity ratios of 12-29 and are of similar magnitude as seen for 1H signals in the same samples. At MAS frequencies above 20 kHz, it was possible to record 2D 19F-13C HETCOR spectra, which contain long-range intra- and intermolecular correlations. Such correlations provide unique distance restraints, inaccessible in conventional experiments without DNP for protein structure determination. Furthermore, systematic quantification of the DNP enhancements as a function of biradical concentration, MAS frequency, temperature, and microwave power is reported. Our work establishes the power of DNP-enhanced 19F MAS NMR spectroscopy for structural characterization of HIV-1 CA assemblies and this approach is anticipated to be applicable to a wide range of large biomolecular systems.