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Biedenbänder T, Bensons ER, Corzilius B. Serial Polarization Transfer by Combination of Cross-Relaxation and Rotational Resonance for Sensitivity-Enhanced Solid-State NMR. Chemphyschem 2023; 24:e202300206. [PMID: 37306393 DOI: 10.1002/cphc.202300206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 06/04/2023] [Accepted: 06/12/2023] [Indexed: 06/13/2023]
Abstract
Methods which induce site-specificity and sensitivity enhancement in solid-state magic-angle spinning NMR spectroscopy become more important for structural biology due to the increasing size of molecules under investigation. Recently, several strategies have been developed to increase site specificity and thus reduce signal overlap. Under dynamic nuclear polarization (DNP) for NMR signal enhancement, it is possible to use cross-relaxation transfer induced by select dynamic groups within the molecules which is exploited by SCREAM-DNP (Specific Cross Relaxation Enhancement by Active Motions under DNP). Here, we present an approach where we additionally reintroduce the homonuclear dipolar coupling with rotational resonance (R2 ) during SCREAM-DNP to further boost the selectivity of the experiment. Detailed analysis of the polarization buildup dynamics of 13 C-methyl polarization source and 13 C-carbonyl target in 2-13 C-ethyl 1-13 C-acetate provides information about the sought-after and spurious transfer pathways. We show that dipolar-recoupled transfer rates greatly exceed the DNP buildup dynamics in our model system, indicating that significantly larger distances can be selectively and efficiently hyperpolarized.
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Affiliation(s)
- Thomas Biedenbänder
- Institute of Chemistry, University of Rostock, Albert-Einstein-Str. 27, 18059, Rostock, Germany
- Department Life, Light & Matter, University of Rostock, Albert-Einstein-Str. 25, 18059, Rostock, Germany
| | - Edvards R Bensons
- Institute of Chemistry, University of Rostock, Albert-Einstein-Str. 27, 18059, Rostock, Germany
- Department Life, Light & Matter, University of Rostock, Albert-Einstein-Str. 25, 18059, Rostock, Germany
| | - Björn Corzilius
- Institute of Chemistry, University of Rostock, Albert-Einstein-Str. 27, 18059, Rostock, Germany
- Department Life, Light & Matter, University of Rostock, Albert-Einstein-Str. 25, 18059, Rostock, Germany
- Leibniz Institute for Catalysis, Albert-Einstein-Str. 29, 18059, Rostock, Germany
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2
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Menzildjian G, Schlagnitweit J, Casano G, Ouari O, Gajan D, Lesage A. Polarizing agents for efficient high field DNP solid-state NMR spectroscopy under magic-angle spinning: from design principles to formulation strategies. Chem Sci 2023; 14:6120-6148. [PMID: 37325158 PMCID: PMC10266460 DOI: 10.1039/d3sc01079a] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 05/09/2023] [Indexed: 06/17/2023] Open
Abstract
Dynamic Nuclear Polarization (DNP) has recently emerged as a cornerstone approach to enhance the sensitivity of solid-state NMR spectroscopy under Magic Angle Spinning (MAS), opening unprecedented analytical opportunities in chemistry and biology. DNP relies on a polarization transfer from unpaired electrons (present in endogenous or exogenous polarizing agents) to nearby nuclei. Developing and designing new polarizing sources for DNP solid-state NMR spectroscopy is currently an extremely active research field per se, that has recently led to significant breakthroughs and key achievements, in particular at high magnetic fields. This review describes recent developments in this area, highlighting key design principles that have been established over time and led to the introduction of increasingly more efficient polarizing sources. After a short introduction, Section 2 presents a brief history of solid-state DNP, highlighting the main polarization transfer schemes. The third section is devoted to the development of dinitroxide radicals, discussing the guidelines that were progressively established to design the fine-tuned molecular structures in use today. In Section 4, we describe recent efforts in developing hybrid radicals composed of a narrow EPR line radical covalently linked to a nitroxide, highlighting the parameters that modulate the DNP efficiency of these mixed structures. Section 5 reviews recent advances in the design of metal complexes suitable for DNP MAS NMR as exogenous electron sources. In parallel, current strategies that exploit metal ions as endogenous polarization sources are discussed. Section 6 briefly describes the recent introduction of mixed-valence radicals. In the last part, experimental aspects regarding sample formulation are reviewed to make best use of these polarizing agents in a broad panel of application fields.
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Affiliation(s)
- Georges Menzildjian
- Centre de RMN à, Très Hauts Champs, Université de Lyon (CNRS/ENS Lyon/UCB Lyon 1) 5 Rue de la doua 69100 Villeurbanne France
| | - Judith Schlagnitweit
- Centre de RMN à, Très Hauts Champs, Université de Lyon (CNRS/ENS Lyon/UCB Lyon 1) 5 Rue de la doua 69100 Villeurbanne France
| | - Gilles Casano
- Aix Marseille Univ., CNRS, Institut de Chimie Radicalaire, UMR 7273 Marseille France
| | - Olivier Ouari
- Aix Marseille Univ., CNRS, Institut de Chimie Radicalaire, UMR 7273 Marseille France
| | - David Gajan
- Centre de RMN à, Très Hauts Champs, Université de Lyon (CNRS/ENS Lyon/UCB Lyon 1) 5 Rue de la doua 69100 Villeurbanne France
| | - Anne Lesage
- Centre de RMN à, Très Hauts Champs, Université de Lyon (CNRS/ENS Lyon/UCB Lyon 1) 5 Rue de la doua 69100 Villeurbanne France
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3
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Shankar Palani R, Mardini M, Quan Y, Griffin RG. Dynamic nuclear polarization with trityl radicals. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2023; 349:107411. [PMID: 36893654 DOI: 10.1016/j.jmr.2023.107411] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 02/17/2023] [Accepted: 02/19/2023] [Indexed: 06/18/2023]
Abstract
Despite the expanding applications of dynamic nuclear polarization (DNP) to problems in biological and materials science, there remain unresolved questions concerning DNP mechanisms. In this paper, we investigate the Zeeman DNP frequency profiles obtained with trityl radicals, OX063 and its partially deuterated analog OX071, in two commonly used glassing matrices based on glycerol and dimethyl sulfoxide (DMSO). When microwave irradiation is applied in the neighborhood of the narrow EPR transition, we observe a dispersive shape in the 1H Zeeman field and the effects are larger in DMSO than in glycerol. With the help of direct DNP observations on 13C and 2H nuclei, we investigate the origin of this dispersive field profile. In particular, we observe a weak nuclear Overhauser effect between 1H and 13C in the sample, which, when irradiating at the positive 1H solid effect (SE) condition, results in a negative enhancement of 13C spins. This observation is not consistent with thermal mixing (TM) being the mechanism responsible for the dispersive shape in the 1H DNP Zeeman frequency profile. Instead, we propose a new mechanism, resonant mixing, involving mixing of nuclear and electron spin states in a simple two-spin system without invoking electron-electron dipolar interactions.
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Affiliation(s)
- Ravi Shankar Palani
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Michael Mardini
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Yifan Quan
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, United States
| | - Robert G Griffin
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, United States.
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4
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Aladin V, Sreemantula AK, Biedenbänder T, Marchanka A, Corzilius B. Specific Signal Enhancement on an RNA-Protein Interface by Dynamic Nuclear Polarization. Chemistry 2023; 29:e202203443. [PMID: 36533705 DOI: 10.1002/chem.202203443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 12/18/2022] [Accepted: 12/19/2022] [Indexed: 12/23/2022]
Abstract
Sensitivity and specificity are both crucial for the efficient solid-state NMR structure determination of large biomolecules. We present an approach that features both advantages by site-specific enhancement of NMR spectroscopic signals from the protein-RNA binding site within a ribonucleoprotein (RNP) by dynamic nuclear polarization (DNP). This approach uses modern biochemical techniques for sparse isotope labeling and exploits the molecular dynamics of 13 C-labeled methyl groups exclusively present in the protein. These dynamics drive heteronuclear cross relaxation and thus allow specific hyperpolarization transfer across the biomolecular complex's interface. For the example of the L7Ae protein in complex with a 26mer guide RNA minimal construct from the box C/D complex in archaea, we demonstrate that a single methyl-nucleotide contact is responsible for most of the polarization transfer to the RNA, and that this specific transfer can be used to boost both NMR spectral sensitivity and specificity by DNP.
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Affiliation(s)
- Victoria Aladin
- Institute of Chemistry, University of Rostock, Albert-Einstein-Str. 27, 18059, Rostock, Germany
- Department Life, Light & Matter, University of Rostock, Albert-Einstein-Str. 25, 18059, Rostock, Germany
| | - Arun K Sreemantula
- Institute for Organic Chemistry and, Centre of Biomolecular Drug Research (BMWZ), Leibniz University Hannover, Schneiderberg 38, 30167, Hannover, Germany
| | - Thomas Biedenbänder
- Institute of Chemistry, University of Rostock, Albert-Einstein-Str. 27, 18059, Rostock, Germany
- Department Life, Light & Matter, University of Rostock, Albert-Einstein-Str. 25, 18059, Rostock, Germany
| | - Alexander Marchanka
- Institute for Organic Chemistry and, Centre of Biomolecular Drug Research (BMWZ), Leibniz University Hannover, Schneiderberg 38, 30167, Hannover, Germany
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Meyerhofstr. 1, 69117, Heidelberg, Germany
| | - Björn Corzilius
- Institute of Chemistry, University of Rostock, Albert-Einstein-Str. 27, 18059, Rostock, Germany
- Department Life, Light & Matter, University of Rostock, Albert-Einstein-Str. 25, 18059, Rostock, Germany
- Leibniz Institute for Catalysis, Albert-Einstein-Str. 29, 18059, Rostock, Germany
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5
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Tagami K, Thicklin R, Jain S, Equbal A, Li M, Zens T, Siaw A, Han S. Design of a cryogen-free high field dual EPR and DNP probe. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2023; 347:107351. [PMID: 36599253 DOI: 10.1016/j.jmr.2022.107351] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 11/29/2022] [Accepted: 11/30/2022] [Indexed: 06/17/2023]
Abstract
We present the design and construction of a cryogen free, dual electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) probe for novel dynamic nuclear polarization (DNP) experiments and concurrent "in situ" analysis of DNP mechanisms. We focus on the probe design that meets the balance between EPR, NMR, and low temperature performance, while maintaining a high degree of versatility: allowing multi-nuclear NMR detection as well as broadband DNP/EPR excitation/detection. To accomplish high NMR/EPR performance, we implement a novel inductively coupled double resonance NMR circuit (1H-13C) in a solid state probe operating at cryogenic temperatures. The components of the circuit were custom built to provide maximum NMR performance, and the physical layout of this circuit was numerically optimized via magnetic field simulations to allow maximum microwave transmission to the sample for optimal EPR performance. Furthermore this probe is based around a cryogen free gas exchange cryostat and has been designed to allow unlimited experiment times down to 8.5 Kelvin with minimal cost. The affordability of EPR/DNP experiment is an extremely important aspect for broader impact with magnetic resonance measurements. The purpose of this article is to provide as complete information as we have available for others with interest in building a dual DNP/EPR instrument based around a cryogen-free cryostat.
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Affiliation(s)
- Kan Tagami
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, United States
| | - Raymond Thicklin
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, United States
| | - Sheetal Jain
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, United States
| | - Asif Equbal
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, United States
| | - Miranda Li
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, United States
| | - Toby Zens
- JEOL USA, Inc., 11 Dearborn Road, Peabody, MA 01960, United States
| | - Anthony Siaw
- JEOL USA, Inc., 11 Dearborn Road, Peabody, MA 01960, United States
| | - Songi Han
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, CA 93106, United States; Department of Chemical Engineering, University of California, Santa Barbara, Santa Barbara, CA 93106, United States.
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6
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Döller SC, Gutmann T, Hoffmann M, Buntkowsky G. A case study on the influence of hydrophilicity on the signal enhancement by dynamic nuclear polarization. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2022; 122:101829. [PMID: 36116176 DOI: 10.1016/j.ssnmr.2022.101829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/25/2022] [Accepted: 09/07/2022] [Indexed: 06/15/2023]
Abstract
In this work, the behavior of four different commercially available polarizing agents is investigated employing the non-ionic model surfactant 1-octanol as analyte. A relative method for the comparison of the proportion of the direct and indirect polarization transfer pathways is established, allowing a direct comparison of the polarization efficacy for different radicals and different parts of the 1-octanol molecule despite differences in radical concentration or sample amount. With this approach, it could be demonstrated that the hydrophilicity is a key factor in the way polarization is transferred from the polarizing agent to the analyte. These findings are confirmed by the determination of buildup times Tb, illustrating that the choice of polarizing agent plays an essential role in ensuring an optimal polarization transfer and therefore the maximum amount of enhancement possible for DNP enhanced NMR measurements.
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Affiliation(s)
- Sonja C Döller
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Str. 8, D-64287, Darmstadt, Germany
| | - Torsten Gutmann
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Str. 8, D-64287, Darmstadt, Germany
| | - Markus Hoffmann
- Department of Chemistry and Biochemistry, State University of New York College at Brockport, Brockport, NY, 14420, USA
| | - Gerd Buntkowsky
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Str. 8, D-64287, Darmstadt, Germany.
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7
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Nanda R, Hazan S, Sauer K, Aladin V, Keinan-Adamsky K, Corzilius B, Shahar R, Zaslansky P, Goobes G. Molecular differences in collagen organization and in organic-inorganic interfacial structure of bones with and without osteocytes. Acta Biomater 2022; 144:195-209. [PMID: 35331939 DOI: 10.1016/j.actbio.2022.03.032] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Revised: 03/10/2022] [Accepted: 03/17/2022] [Indexed: 12/22/2022]
Abstract
Bone is a fascinating biomaterial composed mostly of type-I collagen fibers as an organic phase, apatite as an inorganic phase, and water molecules residing at the interfaces between these phases. They are hierarchically organized with minor constituents such as non-collagenous proteins, citrate ions and glycosaminoglycans into a composite structure that is mechanically durable yet contains enough porosity to accommodate cells and blood vessels. The nanometer scale organization of the collagen fibrous structure and the mineral constituents in bone were recently extensively scrutinized. However, molecular details at the lowest hierarchical level still need to be unraveled to better understand the exact atomic-level arrangement of all these important components in the context of the integral structure of the bone. In this report, we unfold some of the molecular characteristics differentiating between two load-bearing (cleithrum) bones, one from sturgeon fish, where the matrix contains osteocytes and one from pike fish where the bone tissue is devoid of these bone cells. Using enhanced solid-state NMR measurements, we underpin disparities in the collagen fibril structure and dynamics, the mineral phases, the citrate content at the organic-inorganic interface and water penetrability in the two bones. These findings suggest that different strategies are undertaken in the erection of the mineral-organic interfaces in various bones characterized by dissimilar osteogenesis or remodeling pathways and may have implications for the mechanical properties of the particular bone. STATEMENT OF SIGNIFICANCE: Bone boasts unique interactions between collagen fibers and mineral phases through interfaces holding together this bio-composite structure. Over evolution, fish have gone from mineralizing their bones aided by certain bone cells called osteocytes, like tetrapod, to mineralization without these cells. Here, we report atomic level differences in collagen fiber cross linking and organization, porosity of the mineral phases and content of citrate molecules at the bio-mineral interface in bones from modern versus ancient fish. The dissimilar structural features may suggest disparate mechanical properties for the two bones. Fundamental level understanding of the organic and inorganic components in bone and the interfacial interactions holding them together is essential for successful bone repair and for treating better tissue pathologies.
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8
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Chow WY, De Paëpe G, Hediger S. Biomolecular and Biological Applications of Solid-State NMR with Dynamic Nuclear Polarization Enhancement. Chem Rev 2022; 122:9795-9847. [PMID: 35446555 DOI: 10.1021/acs.chemrev.1c01043] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Solid-state NMR spectroscopy (ssNMR) with magic-angle spinning (MAS) enables the investigation of biological systems within their native context, such as lipid membranes, viral capsid assemblies, and cells. However, such ambitious investigations often suffer from low sensitivity due to the presence of significant amounts of other molecular species, which reduces the effective concentration of the biomolecule or interaction of interest. Certain investigations requiring the detection of very low concentration species remain unfeasible even with increasing experimental time for signal averaging. By applying dynamic nuclear polarization (DNP) to overcome the sensitivity challenge, the experimental time required can be reduced by orders of magnitude, broadening the feasible scope of applications for biological solid-state NMR. In this review, we outline strategies commonly adopted for biological applications of DNP, indicate ongoing challenges, and present a comprehensive overview of biological investigations where MAS-DNP has led to unique insights.
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Affiliation(s)
- Wing Ying Chow
- Univ. Grenoble Alpes, CEA, CNRS, Interdisciplinary Research Institute of Grenoble (IRIG), Modeling and Exploration of Materials Laboratory (MEM), 38054 Grenoble, France.,Univ. Grenoble Alpes, CEA, CNRS, Inst. Biol. Struct. IBS, 38044 Grenoble, France
| | - Gaël De Paëpe
- Univ. Grenoble Alpes, CEA, CNRS, Interdisciplinary Research Institute of Grenoble (IRIG), Modeling and Exploration of Materials Laboratory (MEM), 38054 Grenoble, France
| | - Sabine Hediger
- Univ. Grenoble Alpes, CEA, CNRS, Interdisciplinary Research Institute of Grenoble (IRIG), Modeling and Exploration of Materials Laboratory (MEM), 38054 Grenoble, France
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9
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Biedenbänder T, Aladin V, Saeidpour S, Corzilius B. Dynamic Nuclear Polarization for Sensitivity Enhancement in Biomolecular Solid-State NMR. Chem Rev 2022; 122:9738-9794. [PMID: 35099939 DOI: 10.1021/acs.chemrev.1c00776] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Solid-state NMR with magic-angle spinning (MAS) is an important method in structural biology. While NMR can provide invaluable information about local geometry on an atomic scale even for large biomolecular assemblies lacking long-range order, it is often limited by low sensitivity due to small nuclear spin polarization in thermal equilibrium. Dynamic nuclear polarization (DNP) has evolved during the last decades to become a powerful method capable of increasing this sensitivity by two to three orders of magnitude, thereby reducing the valuable experimental time from weeks or months to just hours or days; in many cases, this allows experiments that would be otherwise completely unfeasible. In this review, we give an overview of the developments that have opened the field for DNP-enhanced biomolecular solid-state NMR including state-of-the-art applications at fast MAS and high magnetic field. We present DNP mechanisms, polarizing agents, and sample constitution methods suitable for biomolecules. A wide field of biomolecular NMR applications is covered including membrane proteins, amyloid fibrils, large biomolecular assemblies, and biomaterials. Finally, we present perspectives and recent developments that may shape the field of biomolecular DNP in the future.
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Affiliation(s)
- Thomas Biedenbänder
- Institute of Chemistry, University of Rostock, Albert-Einstein-Straße 3a, 18059 Rostock, Germany.,Department Life, Light & Matter, University of Rostock, Albert-Einstein-Straße 25, 18059 Rostock, Germany
| | - Victoria Aladin
- Institute of Chemistry, University of Rostock, Albert-Einstein-Straße 3a, 18059 Rostock, Germany.,Department Life, Light & Matter, University of Rostock, Albert-Einstein-Straße 25, 18059 Rostock, Germany
| | - Siavash Saeidpour
- Institute of Chemistry, University of Rostock, Albert-Einstein-Straße 3a, 18059 Rostock, Germany.,Department Life, Light & Matter, University of Rostock, Albert-Einstein-Straße 25, 18059 Rostock, Germany
| | - Björn Corzilius
- Institute of Chemistry, University of Rostock, Albert-Einstein-Straße 3a, 18059 Rostock, Germany.,Department Life, Light & Matter, University of Rostock, Albert-Einstein-Straße 25, 18059 Rostock, Germany
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10
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Buntkowsky G, Döller S, Haro-Mares N, Gutmann T, Hoffmann M. Solid-state NMR studies of non-ionic surfactants confined in mesoporous silica. Z PHYS CHEM 2021. [DOI: 10.1515/zpch-2021-3132] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Abstract
This review gives an overview of current trends in the investigation of confined molecules such as higher alcohols, ethylene glycol and polyethylene glycol as guest molecules in neat and functionalized mesoporous silica materials. All these molecules have both hydrophobic and hydrophilic parts. They are characteristic role-models for the investigation of confined surfactants. Their properties are studied by a combination of solid-state NMR and relaxometry with other physicochemical techniques and molecular dynamics techniques. It is shown that this combination delivers unique insights into the structure, arrangement, dynamical properties and the guest-host interactions inside the confinement.
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Affiliation(s)
- Gerd Buntkowsky
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie , Technische Universität Darmstadt , Alarich-Weiss-Str. 8 , D-64287 Darmstadt , Germany
| | - Sonja Döller
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie , Technische Universität Darmstadt , Alarich-Weiss-Str. 8 , D-64287 Darmstadt , Germany
| | - Nadia Haro-Mares
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie , Technische Universität Darmstadt , Alarich-Weiss-Str. 8 , D-64287 Darmstadt , Germany
| | - Torsten Gutmann
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie , Technische Universität Darmstadt , Alarich-Weiss-Str. 8 , D-64287 Darmstadt , Germany
| | - Markus Hoffmann
- Department of Chemistry and Biochemistry , State University of New York College at Brockport , Brockport , NY , 14420 , USA
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11
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Sergeyev IV, Quinn CM, Struppe J, Gronenborn A, Polenova T. Competing Transfer Pathways in Direct and Indirect Dynamic Nuclear Polarization MAS NMR Experiments on HIV-1 Capsid Assemblies: Implications for Sensitivity and Resolution. MAGNETIC RESONANCE (GOTTINGEN, GERMANY) 2021; 2:239-249. [PMID: 34136885 PMCID: PMC8203495 DOI: 10.5194/mr-2-239-2021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 03/23/2021] [Indexed: 04/25/2023]
Abstract
Dynamic nuclear polarization-enhanced (DNP) magic angle spinning (MAS) NMR of biological systems is a rapidly growing field. Large signal enhancements make the technique particularly attractive for signal-limited cases, such as studies of complex biological assemblies or at natural isotopic abundance. However, spectral resolution is considerably reduced compared to ambient-temperature non-DNP spectra. Herein, we report a systematic investigation into sensitivity and resolution of 1D and 2D 13C-detected DNP MAS NMR experiments on HIV-1 CA tubular assemblies. We show that the magnitude and sign of signal enhancement as well as the homogeneous line width are strongly dependent on the biradical concentration, the dominant polarization transfer pathway, and the enhancement buildup time. Our findings provide guidance for optimal choice of sample preparation and experimental conditions in DNP experiments.
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Affiliation(s)
- Ivan V. Sergeyev
- Bruker Biospin Corporation, 15 Fortune Drive, Billerica, MA 01821, United States
| | - Caitlin M. Quinn
- Department of Chemistry and Biochemistry, University of Delaware,
Newark, DE 19716, United States
| | - Jochem Struppe
- Bruker Biospin Corporation, 15 Fortune Drive, Billerica, MA 01821, United States
| | - Angela M. Gronenborn
- Pittsburgh Center for HIV Protein Interactions, University of
Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth
Avenue, Pittsburgh, PA 15261, United States
- Department of Structural Biology, University of Pittsburgh School of Medicine, 3501 Fifth Ave., Pittsburgh, PA 15261, United States
| | - Tatyana Polenova
- Department of Chemistry and Biochemistry, University of Delaware,
Newark, DE 19716, United States
- Pittsburgh Center for HIV Protein Interactions, University of
Pittsburgh School of Medicine, 1051 Biomedical Science Tower 3, 3501 Fifth
Avenue, Pittsburgh, PA 15261, United States
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12
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Berruyer P, Gericke M, Moutzouri P, Jakobi D, Bardet M, Karlson L, Schantz S, Heinze T, Emsley L. Advanced characterization of regioselectively substituted methylcellulose model compounds by DNP enhanced solid-state NMR spectroscopy. Carbohydr Polym 2021; 262:117944. [PMID: 33838821 DOI: 10.1016/j.carbpol.2021.117944] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 03/12/2021] [Accepted: 03/12/2021] [Indexed: 11/16/2022]
Abstract
Dynamic Nuclear Polarization MAS NMR is introduced to characterize model methylcellulose ether compounds at natural isotopic abundance. In particular an approach is provided to determine the position of the methyl ether group within the repeating unit. Specifically, natural abundance 13C-13C correlation experiments are used to characterize model 3-O-methylcellulose and 2,3-O-dimethylcellulose, and identify changes in chemical shifts with respect to native cellulose. We also probe the use of through space connectivity to the closest carbons to the CH3 to identify the substitution site on the cellulose ether. To this end, a series of methylcellulose ethers was prepared by a multistep synthesis approach. Key intermediates in these reactions were 2,6-O-diprotected thexyldimethylsilyl (TDMS) cellulose and 6-O-monoprotected TDMS cellulose methylated under homogeneous conditions. The products had degrees of substitution of 0.99 (3-O-methylcellulose) and 2.03 (2,3-O-dimethylcellulose) with exclusively regioselective substitution. The approaches developed here will allow characterization of the substitution patterns in cellulose ethers.
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Affiliation(s)
- Pierrick Berruyer
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Martin Gericke
- Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich Schiller University of Jena, Centre of Excellence for Polysaccharide Research, Humboldtstraße 10, D-07743 Jena, Germany
| | - Pinelopi Moutzouri
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Dörthe Jakobi
- Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich Schiller University of Jena, Centre of Excellence for Polysaccharide Research, Humboldtstraße 10, D-07743 Jena, Germany
| | - Michel Bardet
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland; Univ. Grenoble Alpes, CEA, IRIG-MEM, Laboratoire de Résonance Magnétique, Grenoble 38000, France
| | - Leif Karlson
- Nouryon Functional Chemicals AB, SE-444 31 Stenungsund, Sweden
| | - Staffan Schantz
- Oral Product Development, Pharmaceutical Technology & Development, Operations, AstraZeneca, Gothenburg, Sweden
| | - Thomas Heinze
- Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich Schiller University of Jena, Centre of Excellence for Polysaccharide Research, Humboldtstraße 10, D-07743 Jena, Germany.
| | - Lyndon Emsley
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
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13
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Heiliger J, Matzel T, Çetiner EC, Schwalbe H, Kuenze G, Corzilius B. Site-specific dynamic nuclear polarization in a Gd(III)-labeled protein. Phys Chem Chem Phys 2020; 22:25455-25466. [PMID: 33103678 DOI: 10.1039/d0cp05021k] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Dynamic nuclear polarization (DNP) of a biomolecule tagged with a polarizing agent has the potential to not only increase NMR sensitivity but also to provide specificity towards the tagging site. Although the general concept has been often discussed, the observation of true site-specific DNP and its dependence on the electron-nuclear distance has been elusive. Here, we demonstrate site-specific DNP in a uniformly isotope-labeled ubiquitin. By recombinant expression of three different ubiquitin point mutants (F4C, A28C, and G75C) post-translationally modified with a Gd3+-chelator tag, localized metal-ion DNP of 13C and 15N is investigated. Effects counteracting the site-specificity of DNP such as nuclear spin-lattice relaxation and proton-driven spin diffusion have been attenuated by perdeuteration of the protein. Particularly for 15N, large DNP enhancement factors on the order of 100 and above as well as localized effects within side-chain resonances differently distributed over the protein are observed. By analyzing the experimental DNP built-up dynamics combined with structural modeling of Gd3+-tags in ubiquitin supported by paramagnetic relaxation enhancement (PRE) in solution, we provide, for the first time, quantitative information on the distance dependence of the initial DNP transfer. We show that the direct 15N DNP transfer rate indeed linearly depends on the square of the hyperfine interaction between the electron and the nucleus following Fermi's golden rule, however, below a certain distance cutoff paramagnetic signal bleaching may dramatically skew the correlation.
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Affiliation(s)
- Jörg Heiliger
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt am Main, Germany
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14
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Stevanato G, Casano G, Kubicki DJ, Rao Y, Esteban Hofer L, Menzildjian G, Karoui H, Siri D, Cordova M, Yulikov M, Jeschke G, Lelli M, Lesage A, Ouari O, Emsley L. Open and Closed Radicals: Local Geometry around Unpaired Electrons Governs Magic-Angle Spinning Dynamic Nuclear Polarization Performance. J Am Chem Soc 2020; 142:16587-16599. [PMID: 32806886 DOI: 10.1021/jacs.0c04911] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The development of magic-angle spinning dynamic nuclear polarization (MAS DNP) has allowed atomic-level characterization of materials for which conventional solid-state NMR is impractical due to the lack of sensitivity. The rapid progress of MAS DNP has been largely enabled through the understanding of rational design concepts for more efficient polarizing agents (PAs). Here, we identify a new design principle which has so far been overlooked. We find that the local geometry around the unpaired electron can change the DNP enhancement by an order of magnitude for two otherwise identical conformers. We present a set of 13 new stable mono- and dinitroxide PAs for MAS DNP NMR where this principle is demonstrated. The radicals are divided into two groups of isomers, named open (O-) and closed (C-), based on the ring conformations in the vicinity of the N-O bond. In all cases, the open conformers exhibit dramatically improved DNP performance as compared to the closed counterparts. In particular, a new urea-based biradical named HydrOPol and a mononitroxide O-MbPyTol yield enhancements of 330 ± 60 and 119 ± 25, respectively, at 9.4 T and 100 K, which are the highest enhancements reported so far in the aqueous solvents used here. We find that while the conformational changes do not significantly affect electron spin-spin distances, they do affect the distribution of the exchange couplings in these biradicals. Electron spin echo envelope modulation (ESEEM) experiments suggest that the improved performance of the open conformers is correlated with higher solvent accessibility.
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Affiliation(s)
- Gabriele Stevanato
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Gilles Casano
- Aix Marseille Université, CNRS, ICR UMR 7273, 13013 Marseille, France
| | - Dominik J Kubicki
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Yu Rao
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Laura Esteban Hofer
- Department of Chemistry, Laboratory of Physical Chemistry, ETH Zurich, 8093 Zurich, Switzerland
| | - Georges Menzildjian
- Centre de RMN à Très Hauts Champs, Université de Lyon (CNRS/ENS de Lyon/UCB-Lyon 1), 69100 Villeurbanne, France
| | - Hakim Karoui
- Aix Marseille Université, CNRS, ICR UMR 7273, 13013 Marseille, France
| | - Didier Siri
- Aix Marseille Université, CNRS, ICR UMR 7273, 13013 Marseille, France
| | - Manuel Cordova
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Maxim Yulikov
- Department of Chemistry, Laboratory of Physical Chemistry, ETH Zurich, 8093 Zurich, Switzerland
| | - Gunnar Jeschke
- Department of Chemistry, Laboratory of Physical Chemistry, ETH Zurich, 8093 Zurich, Switzerland
| | - Moreno Lelli
- Magnetic Resonance Center (CERM/CIRMMP), University of Florence, Via L. Sacconi 6, 50019 Sesto Fiorentino, Florence, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Florence, Italy
| | - Anne Lesage
- Centre de RMN à Très Hauts Champs, Université de Lyon (CNRS/ENS de Lyon/UCB-Lyon 1), 69100 Villeurbanne, France
| | - Olivier Ouari
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Lyndon Emsley
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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15
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Heteronuclear Cross-Relaxation under Dynamic Nuclear Polarization in Nicotine and Caffeine. EXPERIMENTAL RESULTS 2020. [DOI: 10.1017/exp.2020.17] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
AbstractDynamic nuclear polarization (DNP) is a technique in magic-angle spinning (MAS) nuclear magnetic resonance (NMR) which leads to sensitivity enhancement and helps to overcome the issue of low polarization in detected nuclei. Recent research showed, that methyl groups, which show active reorientation dynamics and cause heteronuclear cross relaxation at typical DNP temperatures around 100 K, may be used as a pinpoint source of polarization for selective and site-specific probing. In this study, we investigated the cross-relaxation behavior of methyl groups in nicotine and caffeine under DNP. These effects could be useful for investigating receptor/ligand binding.
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16
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Park H, Uluca-Yazgi B, Heumann S, Schlögl R, Granwehr J, Heise H, Schleker PPM. Heteronuclear cross-relaxation effect modulated by the dynamics of N-functional groups in the solid state under 15N DP-MAS DNP. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2020; 312:106688. [PMID: 32004819 DOI: 10.1016/j.jmr.2020.106688] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 01/12/2020] [Accepted: 01/14/2020] [Indexed: 06/10/2023]
Abstract
In a typical magic-angle spinning (MAS) dynamic nuclear polarization (DNP) nuclear magnetic resonance (NMR) experiment, several mechanisms are simultaneously involved when transferring much larger polarization of electron spins to NMR active nuclei of interest. Recently, specific cross-relaxation enhancement by active motions under DNP (SCREAM-DNP) [Daube et al. JACS 2016] has been reported as one of these mechanisms. Thereby 13C enhancement with inverted sign was observed in a direct polarization (DP) MAS DNP experiment, caused by reorientation dynamics of methyl that was not frozen out at 100 K. Here, we report on the spontaneous polarization transfer from hyperpolarized 1H to both primary amine and ammonium nitrogens, resulting in an additional positive signal enhancement in the 15N NMR spectra during 15N DP-MAS DNP. The cross-relaxation induced signal enhancement (CRE) for 15N is of opposite sign compared to that observed for 13C due to the negative sign of the gyromagnetic ratio of 15N. The influence on CRE efficiency caused by variation of the radical solution composition and by temperature was also investigated.
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Affiliation(s)
- Heeyong Park
- Max Planck Institute for Chemical Energy Conversion, Department of Heterogeneous Reactions, 45470 Mülheim an der Ruhr, Germany; Forschungszentrum Jülich, IEK-9, 52425 Jülich, Germany; RWTH Aachen University, Institute of Technical and Macromolecular Chemistry, 52074 Aachen, Germany
| | - Boran Uluca-Yazgi
- Forschungszentrum Jülich, IBI-7 and JuStruct, 52425 Jülich, Germany; Heinrich Heine Universität Düsseldorf, Institute of Physical Biology, 40225 Düsseldorf, Germany
| | - Saskia Heumann
- Max Planck Institute for Chemical Energy Conversion, Department of Heterogeneous Reactions, 45470 Mülheim an der Ruhr, Germany
| | - Robert Schlögl
- Max Planck Institute for Chemical Energy Conversion, Department of Heterogeneous Reactions, 45470 Mülheim an der Ruhr, Germany; Fritz Haber Institute of the Max Planck Society, 14195 Berlin, Germany
| | - Josef Granwehr
- Forschungszentrum Jülich, IEK-9, 52425 Jülich, Germany; RWTH Aachen University, Institute of Technical and Macromolecular Chemistry, 52074 Aachen, Germany
| | - Henrike Heise
- Forschungszentrum Jülich, IBI-7 and JuStruct, 52425 Jülich, Germany; Heinrich Heine Universität Düsseldorf, Institute of Physical Biology, 40225 Düsseldorf, Germany
| | - P Philipp M Schleker
- Max Planck Institute for Chemical Energy Conversion, Department of Heterogeneous Reactions, 45470 Mülheim an der Ruhr, Germany; Forschungszentrum Jülich, IEK-9, 52425 Jülich, Germany.
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17
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Abstract
Dynamic nuclear polarization (DNP) is one of the most prominent methods of sensitivity enhancement in nuclear magnetic resonance (NMR). Even though solid-state DNP under magic-angle spinning (MAS) has left the proof-of-concept phase and has become an important tool for structural investigations of biomolecules as well as materials, it is still far from mainstream applicability because of the potentially overwhelming combination of unique instrumentation, complex sample preparation, and a multitude of different mechanisms and methods available. In this review, I introduce the diverse field and history of DNP, combining aspects of NMR and electron paramagnetic resonance. I then explain the general concepts and detailed mechanisms relevant at high magnetic field, including solution-state methods based on Overhauser DNP but with a greater focus on the more established MAS DNP methods. Finally, I review practical considerations and fields of application and discuss future developments.
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Affiliation(s)
- Björn Corzilius
- Institute of Chemistry and Department of Life, Light and Matter, University of Rostock, 18059 Rostock, Germany;
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18
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Rodriguez-Gomez A, Chowdhury AD, Caglayan M, Bau JA, Abou-Hamad E, Gascon J. Non-oxidative dehydrogenation of isobutane over supported vanadium oxide: nature of the active sites and coke formation. Catal Sci Technol 2020. [DOI: 10.1039/d0cy01174f] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We combine Raman spectroscopy, EPR, XPS, temperature programmed reduction, XRD, 51V MAS ssNMR, TEM and N2-physisorption to unravel structure–activity relationships during the non-oxidative dehydrogenation of isobutane over a V based catalyst.
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Affiliation(s)
- Alberto Rodriguez-Gomez
- KAUST Catalysis Center (KCC)
- Advanced Catalytic Materials
- King Abdullah University of Science and Technology
- Thuwal 23955
- Saudi Arabia
| | - Abhishek Dutta Chowdhury
- KAUST Catalysis Center (KCC)
- Advanced Catalytic Materials
- King Abdullah University of Science and Technology
- Thuwal 23955
- Saudi Arabia
| | - Mustafa Caglayan
- KAUST Catalysis Center (KCC)
- Advanced Catalytic Materials
- King Abdullah University of Science and Technology
- Thuwal 23955
- Saudi Arabia
| | - Jeremy A. Bau
- KAUST Catalysis Center (KCC)
- Advanced Catalytic Materials
- King Abdullah University of Science and Technology
- Thuwal 23955
- Saudi Arabia
| | - Edy Abou-Hamad
- Core Labs
- King Abdullah University of Science and Technology
- Thuwal 23955
- Saudi Arabia
| | - Jorge Gascon
- KAUST Catalysis Center (KCC)
- Advanced Catalytic Materials
- King Abdullah University of Science and Technology
- Thuwal 23955
- Saudi Arabia
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19
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Exploring Protein Structures by DNP-Enhanced Methyl Solid-State NMR Spectroscopy. J Am Chem Soc 2019; 141:19888-19901. [DOI: 10.1021/jacs.9b11195] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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