title: Dynamic nuclear polarization of nucleic acid with endogenously bound manganese.
abstract: We report the direct dynamic nuclear polarization (DNP) of (13)C nuclei of a uniformly [(13)C,(15)N]-labeled, paramagnetic full-length hammerhead ribozyme (HHRz) complex with Mn(2+) where the enhanced polarization is fully provided by the endogenously bound metal ion and no exogenous polarizing agent is added. A (13)C enhancement factor of ε = 8 was observed by intra-complex DNP at 9.4 T. In contrast, "conventional" indirect and direct DNP experiments were performed using AMUPol as polarizing agent where we obtained a (1)H enhancement factor of ε ≈ 250. Comparison with the diamagnetic (Mg(2+)) HHRz complex shows that the presence of Mn(2+) only marginally influences the (DNP-enhanced) NMR properties of the RNA. Furthermore two-dimensional correlation spectra ((15)N-(13)C and (13)C-(13)C) reveal structural inhomogeneity in the frozen, amorphous state indicating the coexistence of several conformational states. These demonstrations of intra-complex DNP using an endogenous metal ion as well as DNP-enhanced MAS NMR of RNA in general yield important information for the development of new methods in structural biology.
authors.affiliation: Institute of Physical und Theoretical Chemistry, Institute of Biophysical Chemistry und Center for Biomolecular Magnetic Resonance (BMRZ), Goethe University, Max-von-Laue-Str. 7-9, 60438, Frankfurt am Main, Germany.|Werner Siemens Imaging Center and Department of Preclinical Imaging and Radiopharmacy, University of Tübingen, Röntgenweg 13, 72076, Tübingen, Germany.
authors.forename: Patricia
authors.initials: P
authors.lastname: Wenk
authors.affiliation: Institute of Physical und Theoretical Chemistry, Institute of Biophysical Chemistry und Center for Biomolecular Magnetic Resonance (BMRZ), Goethe University, Max-von-Laue-Str. 7-9, 60438, Frankfurt am Main, Germany.
authors.forename: Monu
authors.initials: M
authors.lastname: Kaushik
authors.affiliation: Institute of Physical und Theoretical Chemistry, Institute of Biophysical Chemistry und Center for Biomolecular Magnetic Resonance (BMRZ), Goethe University, Max-von-Laue-Str. 7-9, 60438, Frankfurt am Main, Germany.
authors.forename: Diane
authors.initials: D
authors.lastname: Richter
authors.affiliation: Department of Biology, Technical University Darmstadt, Schnittspahnstraße 10, 64287, Darmstadt, Germany.
authors.forename: Marc
authors.initials: M
authors.lastname: Vogel
authors.affiliation: Department of Biology, Technical University Darmstadt, Schnittspahnstraße 10, 64287, Darmstadt, Germany.
authors.forename: Beatrix
authors.initials: B
authors.lastname: Suess
authors.affiliation: Institute of Physical und Theoretical Chemistry, Institute of Biophysical Chemistry und Center for Biomolecular Magnetic Resonance (BMRZ), Goethe University, Max-von-Laue-Str. 7-9, 60438, Frankfurt am Main, Germany. corzilius@em.uni-frankfurt.de.
authors.forename: Björn
authors.initials: B
authors.lastname: Corzilius
mesh_terms: D001483:Base Sequence; D002247:Carbon Isotopes; D008345:Manganese / Q000737:chemistry*; D008969:Molecular Sequence Data; D009587:Nitrogen Isotopes; D019906:Nuclear Magnetic Resonance, Biomolecular; D009690:Nucleic Acid Conformation; D009696:Nucleic Acids / Q000737:chemistry*; D013997:Time Factors
chemical_list: D002247:Carbon Isotopes; D009587:Nitrogen Isotopes; D009696:Nucleic Acids; D008345:Manganese
keywords: Dynamic nuclear polarization (DNP); EPR; Polarizing agent; RNA; Solid-state NMR; Transition metal