title: Temperature dependence of cross-effect dynamic nuclear polarization in rotating solids: advantages of elevated temperatures.
abstract: Dynamic nuclear polarization exploits electron spin polarization to boost signal-to-noise in magic-angle-spinning (MAS) NMR, creating new opportunities in materials science, structural biology, and metabolomics studies. Since protein NMR spectra recorded under DNP conditions can show improved spectral resolution at 180-200 K compared to 110 K, we investigate the effects of AMUPol and various deuterated TOTAPOL isotopologues on sensitivity and spectral resolution at these temperatures, using proline and reproducibly prepared SH3 domain samples. The TOTAPOL deuteration pattern is optimized for protein DNP MAS NMR, and signal-to-noise per unit time measurements demonstrate the high value of TOTAPOL isotopologues for Protein DNP MAS NMR at 180-200 K. The combined effects of enhancement, depolarization, and proton longitudinal relaxation are surprisingly sample-specific. At 200 K, DNP on SH3 domain standard samples yields a 15-fold increase in signal-to-noise over a sample without radicals. 2D and 3D NCACX/NCOCX spectra were recorded at 200 K within 1 and 13 hours, respectively. Decreasing enhancements with increasing2H-content at the CH2sites of the TEMPO rings in CD3-TOTAPOL highlight the importance of protons in a sphere of 4-6 Å around the nitroxyl group, presumably for polarization pickup from electron spins.
authors: Department for Structural Biology, Leibniz-Institut für Molekulare Pharmakologie, Robert Roessle-Str. 10, 13125 Berlin, Germany. oschkinat@fmp-berlin.de.
authors: Michel-Andreas
authors: http://orcid.org/0000-0002-8501-6321
authors: MA
authors: Geiger
authors: Department for Structural Biology, Leibniz-Institut für Molekulare Pharmakologie, Robert Roessle-Str. 10, 13125 Berlin, Germany. oschkinat@fmp-berlin.de.
authors: Marcella
authors: M
authors: Orwick-Rydmark
authors: Department for Structural Biology, Leibniz-Institut für Molekulare Pharmakologie, Robert Roessle-Str. 10, 13125 Berlin, Germany. oschkinat@fmp-berlin.de.
authors: Katharina
authors: K
authors: Märker
authors: Department for Structural Biology, Leibniz-Institut für Molekulare Pharmakologie, Robert Roessle-Str. 10, 13125 Berlin, Germany. oschkinat@fmp-berlin.de.
authors: W Trent
authors: WT
authors: Franks
authors: Goethe-University Frankfurt am Main, Institute of Physical and Theoretical Chemistry and Center for Biomolecular Magnetic Resonance, Max von Laue Str. 7, 60438 Frankfurt am Main, Germany.
authors: Dmitry
authors: D
authors: Akhmetzyanov
authors: Department for Structural Biology, Leibniz-Institut für Molekulare Pharmakologie, Robert Roessle-Str. 10, 13125 Berlin, Germany. oschkinat@fmp-berlin.de.
authors: Daniel
authors: D
authors: Stöppler
authors: Department for Structural Biology, Leibniz-Institut für Molekulare Pharmakologie, Robert Roessle-Str. 10, 13125 Berlin, Germany. oschkinat@fmp-berlin.de.
authors: Maximilian
authors: M
authors: Zinke
authors: Department for Structural Biology, Leibniz-Institut für Molekulare Pharmakologie, Robert Roessle-Str. 10, 13125 Berlin, Germany. oschkinat@fmp-berlin.de.
authors: Edgar
authors: E
authors: Specker
authors: Department for Structural Biology, Leibniz-Institut für Molekulare Pharmakologie, Robert Roessle-Str. 10, 13125 Berlin, Germany. oschkinat@fmp-berlin.de.
authors: Marc
authors: M
authors: Nazaré
authors: Department for Structural Biology, Leibniz-Institut für Molekulare Pharmakologie, Robert Roessle-Str. 10, 13125 Berlin, Germany. oschkinat@fmp-berlin.de.
authors: Anne
authors: A
authors: Diehl
authors: Department for Structural Biology, Leibniz-Institut für Molekulare Pharmakologie, Robert Roessle-Str. 10, 13125 Berlin, Germany. oschkinat@fmp-berlin.de.
authors: Barth-Jan
authors: BJ
authors: van Rossum
authors: Bruker BioSpin S.A.S., 34 rue de l'industire, 67166 Wissembourg, France.
authors: Fabien
authors: F
authors: Aussenac
authors: Goethe-University Frankfurt am Main, Institute of Physical and Theoretical Chemistry and Center for Biomolecular Magnetic Resonance, Max von Laue Str. 7, 60438 Frankfurt am Main, Germany.
authors: Thomas
authors: T
authors: Prisner
authors: Department for Structural Biology, Leibniz-Institut für Molekulare Pharmakologie, Robert Roessle-Str. 10, 13125 Berlin, Germany. oschkinat@fmp-berlin.de.
authors: Ümit
authors: Ü
authors: Akbey
authors: Department for Structural Biology, Leibniz-Institut für Molekulare Pharmakologie, Robert Roessle-Str. 10, 13125 Berlin, Germany. oschkinat@fmp-berlin.de.
authors: Hartmut
authors: H
authors: Oschkinat