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

• Published in: Journal of the American Chemical Society Vol. 141; no. 14; pp. 5681 - 5691
• Main Authors: Lu, Manman, Wang, Mingzhang, Sergeyev, Ivan V, Quinn, Caitlin M, Struppe, Jochem, Rosay, Melanie, Maas, Werner, Gronenborn, Angela M, Polenova, Tatyana
• Format: Journal Article
• Language: English
• Published: United States 10.04.2019
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/jacs.8b09216

We report remarkably high, up to 100-fold, signal enhancements in F dynamic nuclear polarization (DNP) magic angle spinning (MAS) spectra at 14.1 T on HIV-1 capsid protein (CA) assemblies. These enhancements correspond to absolute sensitivity ratios of 12-29 and are of similar magnitude to those seen for H signals in the same samples. At MAS frequencies above 20 kHz, it was possible to record 2D F- C 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 F 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.