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Du Y, Frank D, Chen Z, Struppe J, Su Y. Ultrafast magic angle spinning NMR characterization of pharmaceutical solid polymorphism: A posaconazole example. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2023; 346:107352. [PMID: 36535214 DOI: 10.1016/j.jmr.2022.107352] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Revised: 11/30/2022] [Accepted: 12/02/2022] [Indexed: 06/17/2023]
Abstract
Protons represent the most NMR-sensitive nucleus in pharmaceutical compounds. Therefore, proton-detected solid-state NMR techniques under fast magic angle spinning are among the few solutions to overcome the challenge of low sensitivity to analyze natural abundant drug substances and products. In this study, we report the structural characterization of crystal polymorphs of a commercial drug molecule, posaconazole, with a relatively large molecular weight of 700.8 g·mol-1 and at the natural abundance. The enhanced sensitivity and resolution at 100 kHz MAS enables the exploration of the distinct intermolecular packing in posaconazole forms I, III, and γ. These results demonstrate that proton-detected homo- and heteronuclear correlation methods can probe the structural details of pharmaceutical polymorphism.
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Affiliation(s)
- Yong Du
- Analytical Research & Development, Merck & Co., Inc, Rahway, NJ 07065, USA
| | - Derek Frank
- Process Research & Development, Merck & Co., Inc, Rahway, NJ 07065, USA
| | - Zhenxuan Chen
- Analytical Research & Development, Merck & Co., Inc, Rahway, NJ 07065, USA
| | | | - Yongchao Su
- Analytical Research & Development, Merck & Co., Inc, Rahway, NJ 07065, USA.
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2
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Ahlawat S, Mopidevi SMV, Taware PP, Raran-Kurussi S, Mote KR, Agarwal V. Assignment of aromatic side-chain spins and characterization of their distance restraints at fast MAS. J Struct Biol X 2022; 7:100082. [PMID: 36618437 PMCID: PMC9817166 DOI: 10.1016/j.yjsbx.2022.100082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 11/18/2022] [Accepted: 12/27/2022] [Indexed: 12/30/2022] Open
Abstract
The assignment of aromatic side-chain spins has always been more challenging than assigning backbone and aliphatic spins. Selective labeling combined with mutagenesis has been the approach for assigning aromatic spins. This manuscript reports a method for assigning aromatic spins in a fully protonated protein by connecting them to the backbone atoms using a low-power TOBSY sequence. The pulse sequence employs residual polarization and sequential acquisitions techniques to record HN- and HC-detected spectra in a single experiment. The unambiguous assignment of aromatic spins also enables the characterization of 1H-1H distance restraints involving aromatic spins. Broadband (RFDR) and selective (BASS-SD) recoupling sequences were used to generate HN-ΗC, HC-HN and HC-HC restraints involving the side-chain proton spins of aromatic residues. This approach has been demonstrated on a fully protonated U-[13C,15N] labeled GB1 sample at 95-100 kHz MAS.
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Affiliation(s)
- Sahil Ahlawat
- Tata Institute of Fundamental Research Hyderabad, Sy. No. 36/P, Gopanpally Village, Serilingampally Mandal, Ranga Reddy District, Hyderabad 500 046, India
| | - Subbarao Mohana Venkata Mopidevi
- Tata Institute of Fundamental Research Hyderabad, Sy. No. 36/P, Gopanpally Village, Serilingampally Mandal, Ranga Reddy District, Hyderabad 500 046, India
| | - Pravin P. Taware
- Tata Institute of Fundamental Research Hyderabad, Sy. No. 36/P, Gopanpally Village, Serilingampally Mandal, Ranga Reddy District, Hyderabad 500 046, India
| | - Sreejith Raran-Kurussi
- Tata Institute of Fundamental Research Hyderabad, Sy. No. 36/P, Gopanpally Village, Serilingampally Mandal, Ranga Reddy District, Hyderabad 500 046, India
| | - Kaustubh R. Mote
- Tata Institute of Fundamental Research Hyderabad, Sy. No. 36/P, Gopanpally Village, Serilingampally Mandal, Ranga Reddy District, Hyderabad 500 046, India
| | - Vipin Agarwal
- Tata Institute of Fundamental Research Hyderabad, Sy. No. 36/P, Gopanpally Village, Serilingampally Mandal, Ranga Reddy District, Hyderabad 500 046, India
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3
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Hartman JD, Mathews A, Harper JK. Fast and Accurate Electric Field Gradient Calculations in Molecular Solids With Density Functional Theory. Front Chem 2021; 9:751711. [PMID: 34692646 PMCID: PMC8529703 DOI: 10.3389/fchem.2021.751711] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Accepted: 09/20/2021] [Indexed: 11/24/2022] Open
Abstract
Modern approaches for calculating electric field gradient (EFF) tensors in molecular solids rely upon plane-wave calculations employing periodic boundary conditions (PBC). In practice, models employing PBCs are limited to generalized gradient approximation (GGA) density functionals. Hybrid density functionals applied in the context of gauge-including atomic orbital (GIAO) calculations have been shown to substantially improve the accuracy of predicted NMR parameters. Here we propose an efficient method that effectively combines the benefits of both periodic calculations and single-molecule techniques for predicting electric field gradient tensors in molecular solids. Periodic calculations using plane-wave basis sets were used to model the crystalline environment. We then introduce a molecular correction to the periodic result obtained from a single-molecule calculation performed with a hybrid density functional. Single-molecule calculations performed using hybrid density functionals were found to significantly improve the agreement of predicted 17O quadrupolar coupling constants (C q ) with experiment. We demonstrate a 31% reduction in the RMS error for the predicted 17O C q values relative to standard plane-wave methods using a carefully constructed test set comprised of 22 oxygen-containing molecular crystals. We show comparable improvements in accuracy using five different hybrid density functionals and find predicted C q values to be relatively insensitive to the choice of basis set used in the single molecule calculation. Finally, the utility of high-accuracy 17O C q predictions is demonstrated by examining the disordered 4-Nitrobenzaldehyde crystal structure.
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Affiliation(s)
- Joshua D. Hartman
- Department of Chemistry, Mt. San Jacinto College, Menifee, CA, United States
| | - Amanda Mathews
- Department of Chemistry, Mt. San Jacinto College, Menifee, CA, United States
| | - James K. Harper
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, United States
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4
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Mathews A, Hartman JD. Accurate fragment-based 51-V chemical shift predictions in molecular crystals. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2021; 114:101733. [PMID: 34082261 DOI: 10.1016/j.ssnmr.2021.101733] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 04/28/2021] [Accepted: 04/28/2021] [Indexed: 06/12/2023]
Abstract
Nuclear magnetic resonance (NMR) spectroscopy plays a crucial role in determining molecular structure for complex biological and pharmaceutical compounds. NMR investigations are increasingly reliant on computation for mapping spectral features to chemical structures. Here we benchmark the accuracy of fragment-based 51V chemical shielding tensor calculations using a training set comprised of 10 biologically and pharmaceutically relevant oxovanadium complexes. Using our self-consistent reproduction of the Madelung potential (SCRMP) electrostatic embedding model, we demonstrate comparable performance between fragment methods and computationally demanding cluster-based techniques. Specifically, fragment methods employing hybrid density functionals are capable of reproducing the experimental 51V isotropic chemical shifts with a training set rms error of ~9 ppm, representing a 20% improvement over traditional plane wave techniques. We provide training set-derived linear regression models for mapping the absolute shieldings obtained from computation to the experimentally determined chemical shifts using four common density functionals; PBE0, B3LYP, PBE, and BLYP. Finally, we establish the utility of fragment methods and the reported regression parameters examining four oxovanadium structures excluded from the training set including the tetracoordinate oxovanadium silicate [Formula: see text] , VO15NGlySalbz which contains redox-active ligands, and the solid-state form of the common 51V NMR reference compound VOCl3.
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Affiliation(s)
- Amanda Mathews
- Department of Chemistry, Mt. San Jacinto College, Menifee, CA, USA
| | - Joshua D Hartman
- Department of Chemistry, Mt. San Jacinto College, Menifee, CA, USA.
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5
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Wang L, Harper JK. Refining crystal structures using 13C NMR chemical shift tensors as a target function. CrystEngComm 2021. [DOI: 10.1039/d1ce00960e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A two-step process is described for refining crystal structures from any source.
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Affiliation(s)
- Luther Wang
- Department of Chemistry and Biochemistry, Brigham Young University, Provo UT 84602, USA
| | - James K. Harper
- Department of Chemistry and Biochemistry, Brigham Young University, Provo UT 84602, USA
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6
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Chalek KR, Dong X, Tong F, Kudla RA, Zhu L, Gill AD, Xu W, Yang C, Hartman JD, Magalhães A, Al-Kaysi RO, Hayward RC, Hooley RJ, Beran GJO, Bardeen CJ, Mueller LJ. Bridging photochemistry and photomechanics with NMR crystallography: the molecular basis for the macroscopic expansion of an anthracene ester nanorod. Chem Sci 2020; 12:453-463. [PMID: 34163608 PMCID: PMC8178812 DOI: 10.1039/d0sc05118g] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 10/29/2020] [Indexed: 12/28/2022] Open
Abstract
Crystals composed of photoreactive molecules represent a new class of photomechanical materials with the potential to generate large forces on fast timescales. An example is the photodimerization of 9-tert-butyl-anthracene ester (9TBAE) in molecular crystal nanorods that leads to an average elongation of 8%. Previous work showed that this expansion results from the formation of a metastable crystalline product. In this article, it is shown how a novel combination of ensemble oriented-crystal solid-state NMR, X-ray diffraction, and first principles computational modeling can be used to establish the absolute unit cell orientations relative to the shape change, revealing the atomic-resolution mechanism for the photomechanical response and enabling the construction of a model that predicts an elongation of 7.4%, in good agreement with the experimental value. According to this model, the nanorod expansion does not result from an overall change in the volume of the unit cell, but rather from an anisotropic rearrangement of the molecular contents. The ability to understand quantitatively how molecular-level photochemistry generates mechanical displacements allows us to predict that the expansion could be tuned from +9% to -9.5% by controlling the initial orientation of the unit cell with respect to the nanorod axis. This application of NMR-assisted crystallography provides a new tool capable of tying the atomic-level structural rearrangement of the reacting molecular species to the mechanical response of a nanostructured sample.
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Affiliation(s)
- Kevin R Chalek
- Department of Chemistry, University of California-Riverside Riverside CA 92521 USA
| | - Xinning Dong
- Department of Chemistry, University of California-Riverside Riverside CA 92521 USA
| | - Fei Tong
- Department of Chemistry, University of California-Riverside Riverside CA 92521 USA
| | - Ryan A Kudla
- Department of Chemistry, University of California-Riverside Riverside CA 92521 USA
| | - Lingyan Zhu
- Department of Chemistry, University of California-Riverside Riverside CA 92521 USA
| | - Adam D Gill
- Department of Biochemistry, University of California-Riverside Riverside CA 92521 USA
| | - Wenwen Xu
- Department of Chemical and Biological Engineering, University of Colorado Boulder 3415 Colorado Ave. Boulder CO 80303 USA
| | - Chen Yang
- Department of Chemistry, University of California-Riverside Riverside CA 92521 USA
| | - Joshua D Hartman
- Department of Chemistry, University of California-Riverside Riverside CA 92521 USA
| | - Alviclér Magalhães
- Department of Organic Chemistry, Institute of Chemistry, Federal University of Rio de Janeiro Rio de Janeiro RJ 21941-909 Brazil
| | - Rabih O Al-Kaysi
- College of Science and Health Professions-3124, King Saud Bin Abdulaziz University for Health Sciences, King Abdullah International Medical Research Center, Ministry of National Guard Health Affairs Riyadh 11426 Kingdom of Saudi Arabia
| | - Ryan C Hayward
- Department of Chemical and Biological Engineering, University of Colorado Boulder 3415 Colorado Ave. Boulder CO 80303 USA
| | - Richard J Hooley
- Department of Chemistry, University of California-Riverside Riverside CA 92521 USA
| | - Gregory J O Beran
- Department of Chemistry, University of California-Riverside Riverside CA 92521 USA
| | | | - Leonard J Mueller
- Department of Chemistry, University of California-Riverside Riverside CA 92521 USA
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7
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Zhao W, Fernando LD, Kirui A, Deligey F, Wang T. Solid-state NMR of plant and fungal cell walls: A critical review. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2020; 107:101660. [PMID: 32251983 DOI: 10.1016/j.ssnmr.2020.101660] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Accepted: 03/17/2020] [Indexed: 05/22/2023]
Abstract
The cell walls of plants and microbes are a central source for bio-renewable energy and the major targets of antibiotics and antifungal agents. It is highly challenging to determine the molecular structure of complex carbohydrates, protein and lignin, and their supramolecular assembly in intact cell walls. This article selectively highlights the recent breakthroughs that employ 13C/15N solid-state NMR techniques to elucidate the architecture of fungal cell walls in Aspergillus fumigatus and the primary and secondary cell walls in a large variety of plant species such as Arabidopsis, Brachypodium, maize, and spruce. Built upon these pioneering studies, we further summarize the underexplored aspects of fungal and plant cell walls. The new research opportunities introduced by innovative methods, such as the detection of proton and quadrupolar nuclei on ultrahigh-field magnets and under fast magic-angle spinning, paramagnetic probes, natural-abundance DNP, and software development, are also critically discussed.
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Affiliation(s)
- Wancheng Zhao
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Liyanage D Fernando
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Alex Kirui
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Fabien Deligey
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Tuo Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA.
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8
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Matlahov I, van der Wel PCA. Hidden motions and motion-induced invisibility: Dynamics-based spectral editing in solid-state NMR. Methods 2018; 148:123-135. [PMID: 29702226 DOI: 10.1016/j.ymeth.2018.04.015] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 04/05/2018] [Accepted: 04/16/2018] [Indexed: 10/17/2022] Open
Abstract
Solid-state nuclear magnetic resonance (ssNMR) spectroscopy enables the structural characterization of a diverse array of biological assemblies that include amyloid fibrils, non-amyloid aggregates, membrane-associated proteins and viral capsids. Such biological samples feature functionally relevant molecular dynamics, which often affect different parts of the sample in different ways. Solid-state NMR experiments' sensitivity to dynamics represents a double-edged sword. On the one hand, it offers a chance to measure dynamics in great detail. On the other hand, certain types of motion lead to signal loss and experimental inefficiencies that at first glance interfere with the application of ssNMR to overly dynamic proteins. Dynamics-based spectral editing (DYSE) ssNMR methods leverage motion-dependent signal losses to simplify spectra and enable the study of sub-structures with particular motional properties.
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Affiliation(s)
- Irina Matlahov
- Department of Structural Biology, University of Pittsburgh School of Medicine, 3501 Fifth Ave., Pittsburgh, PA 15213, USA
| | - Patrick C A van der Wel
- Department of Structural Biology, University of Pittsburgh School of Medicine, 3501 Fifth Ave., Pittsburgh, PA 15213, USA; Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
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9
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Tang X, Jia X, Huang Z. Challenges and opportunities for alkane functionalisation using molecular catalysts. Chem Sci 2017; 9:288-299. [PMID: 29629098 PMCID: PMC5870200 DOI: 10.1039/c7sc03610h] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 11/07/2017] [Indexed: 11/28/2022] Open
Abstract
The conversion of vast low-value saturated hydrocarbons into valuable chemicals is of great interest.
The conversion of vast low-value saturated hydrocarbons into valuable chemicals is of great interest. Thanks to the progression of organometallic and coordination chemistry, transition metal catalysed C sp3–H bond functionalisation has now become a powerful tool for alkane transformations. Specifically, methods for alkane functionalisation include radical initiated C–H functionalisation, carbene/nitrene insertion, and transition metal catalysed C–H bond activation. This perspective provides a systematic and concise overview of each protocol, highlighting the factors that govern regioselectivity in these reactions. The challenges of the existing catalytic tactics and future directions for catalyst development in this field will be presented.
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Affiliation(s)
- Xinxin Tang
- State Key Laboratory of Organometallic Chemistry , Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences , Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China .
| | - Xiangqing Jia
- State Key Laboratory of Organometallic Chemistry , Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences , Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China .
| | - Zheng Huang
- State Key Laboratory of Organometallic Chemistry , Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences , Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China .
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10
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Hartman J, Day GM, Beran GJO. Enhanced NMR Discrimination of Pharmaceutically Relevant Molecular Crystal Forms through Fragment-Based Ab Initio Chemical Shift Predictions. CRYSTAL GROWTH & DESIGN 2016; 16:6479-6493. [PMID: 27829821 PMCID: PMC5095663 DOI: 10.1021/acs.cgd.6b01157] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 09/09/2016] [Indexed: 05/10/2023]
Abstract
Chemical shift prediction plays an important role in the determination or validation of crystal structures with solid-state nuclear magnetic resonance (NMR) spectroscopy. One of the fundamental theoretical challenges lies in discriminating variations in chemical shifts resulting from different crystallographic environments. Fragment-based electronic structure methods provide an alternative to the widely used plane wave gauge-including projector augmented wave (GIPAW) density functional technique for chemical shift prediction. Fragment methods allow hybrid density functionals to be employed routinely in chemical shift prediction, and we have recently demonstrated appreciable improvements in the accuracy of the predicted shifts when using the hybrid PBE0 functional instead of generalized gradient approximation (GGA) functionals like PBE. Here, we investigate the solid-state 13C and 15N NMR spectra for multiple crystal forms of acetaminophen, phenobarbital, and testosterone. We demonstrate that the use of the hybrid density functional instead of a GGA provides both higher accuracy in the chemical shifts and increased discrimination among the different crystallographic environments. Finally, these results also provide compelling evidence for the transferability of the linear regression parameters mapping predicted chemical shieldings to chemical shifts that were derived in an earlier study.
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Affiliation(s)
- Joshua
D. Hartman
- Department
of Chemistry, University of California, Riverside, California 92521 United States
| | - Graeme M. Day
- School
of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, United Kingdom
| | - Gregory J. O. Beran
- Department
of Chemistry, University of California, Riverside, California 92521 United States
- E-mail:
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11
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Dekhil M, Mollica G, Bonniot TT, Ziarelli F, Thureau P, Viel S. Determining carbon-carbon connectivities in natural abundance organic powders using dipolar couplings. Chem Commun (Camb) 2016; 52:8565-8. [PMID: 27319808 DOI: 10.1039/c6cc04202c] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present a solid-state NMR methodology capable of investigating the carbon skeleton of natural abundance organic powders. The methodology is based on the (13)C-(13)C dipolar coupling interaction and allows carbon-carbon connectivities to be unambiguously established for a wide range of organic solids. This methodology is particularly suitable for disordered solids, such as natural or synthetic macromolecules, which cannot be studied using conventional diffraction or NMR techniques.
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Affiliation(s)
- Myriam Dekhil
- Aix-Marseille Université, CNRS, ICR (UMR 7273), 13397 Marseille, France.
| | - Giulia Mollica
- Aix-Marseille Université, CNRS, ICR (UMR 7273), 13397 Marseille, France.
| | | | - Fabio Ziarelli
- Aix-Marseille Université, Centrale Marseille, CNRS, Fédération des Sciences Chimiques de Marseille (FR 1739), 13397 Marseille, France
| | - Pierre Thureau
- Aix-Marseille Université, CNRS, ICR (UMR 7273), 13397 Marseille, France.
| | - Stéphane Viel
- Aix-Marseille Université, CNRS, ICR (UMR 7273), 13397 Marseille, France. and Institut Universitaire de France, 75005 Paris, France
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12
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Zhang R, Ramamoorthy A. Constant-time 2D and 3D through-bond correlation NMR spectroscopy of solids under 60 kHz MAS. J Chem Phys 2016; 144:034202. [PMID: 26801026 PMCID: PMC4723396 DOI: 10.1063/1.4940029] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 01/04/2016] [Indexed: 12/13/2022] Open
Abstract
Establishing connectivity and proximity of nuclei is an important step in elucidating the structure and dynamics of molecules in solids using magic angle spinning (MAS) NMR spectroscopy. Although recent studies have successfully demonstrated the feasibility of proton-detected multidimensional solid-state NMR experiments under ultrafast-MAS frequencies and obtaining high-resolution spectral lines of protons, assignment of proton resonances is a major challenge. In this study, we first re-visit and demonstrate the feasibility of 2D constant-time uniform-sign cross-peak correlation (CTUC-COSY) NMR experiment on rigid solids under ultrafast-MAS conditions, where the sensitivity of the experiment is enhanced by the reduced spin-spin relaxation rate and the use of low radio-frequency power for heteronuclear decoupling during the evolution intervals of the pulse sequence. In addition, we experimentally demonstrate the performance of a proton-detected pulse sequence to obtain a 3D (1)H/(13)C/(1)H chemical shift correlation spectrum by incorporating an additional cross-polarization period in the CTUC-COSY pulse sequence to enable proton chemical shift evolution and proton detection in the incrementable t1 and t3 periods, respectively. In addition to through-space and through-bond (13)C/(1)H and (13)C/(13)C chemical shift correlations, the 3D (1)H/(13)C/(1)H experiment also provides a COSY-type (1)H/(1)H chemical shift correlation spectrum, where only the chemical shifts of those protons, which are bonded to two neighboring carbons, are correlated. By extracting 2D F1/F3 slices ((1)H/(1)H chemical shift correlation spectrum) at different (13)C chemical shift frequencies from the 3D (1)H/(13)C/(1)H spectrum, resonances of proton atoms located close to a specific carbon atom can be identified. Overall, the through-bond and through-space homonuclear/heteronuclear proximities determined from the 3D (1)H/(13)C/(1)H experiment would be useful to study the structure and dynamics of a variety of chemical and biological solids.
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Affiliation(s)
- Rongchun Zhang
- Biophysics and Department of Chemistry, The University of Michigan, Ann Arbor, Michigan 48109-1055, USA
| | - Ayyalusamy Ramamoorthy
- Biophysics and Department of Chemistry, The University of Michigan, Ann Arbor, Michigan 48109-1055, USA
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13
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Yang C, Zhu L, Kudla RA, Hartman JD, Al-Kaysi RO, Monaco S, Schatschneider B, Magalhães A, Beran GJO, Bardeen CJ, Mueller LJ. Crystal structure of the meta-stable intermediate in the photomechanical, crystal-to-crystal reaction of 9-tert-butyl anthracene ester. CrystEngComm 2016. [DOI: 10.1039/c6ce00742b] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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14
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Wang JR, Zhu B, Yu Q, Mei X. Selective crystallization of vitamin D3for the preparation of novel conformational polymorphs with distinctive chemical stability. CrystEngComm 2016. [DOI: 10.1039/c5ce02431e] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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15
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Powell J, Kalakewich K, Uribe-Romo FJ, Harper JK. Solid-state NMR and DFT predictions of differences in COOH hydrogen bonding in odd and even numbered n-alkyl fatty acids. Phys Chem Chem Phys 2016; 18:12541-9. [DOI: 10.1039/c6cp00416d] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
n-Alkyl fatty acids with an even or odd number of carbons are predicted to differ in COOH hydrogen bonding in the solid state.
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Affiliation(s)
- Jacob Powell
- Department of Chemistry
- University of Central Florida
- Orlando
- USA
| | | | | | - James K. Harper
- Department of Chemistry
- University of Central Florida
- Orlando
- USA
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16
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Kalakewich K, Iuliucci R, Mueller KT, Eloranta H, Harper JK. Monitoring the refinement of crystal structures with 15N solid-state NMR shift tensor data. J Chem Phys 2015; 143:194702. [DOI: 10.1063/1.4935367] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Affiliation(s)
- Keyton Kalakewich
- Department of Chemistry, University of Central Florida, 4104 Libra Drive, Orlando, Florida 32816, USA
| | - Robbie Iuliucci
- Department of Chemistry, Washington and Jefferson College, 60 Lincoln Street, Washington, Pennsylvania 15301, USA
| | - Karl T. Mueller
- Department of Chemistry, Penn State University, University Park, Pennsylvania 16802, USA
- Physical and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
| | - Harriet Eloranta
- Department of Chemistry, University of Central Florida, 4104 Libra Drive, Orlando, Florida 32816, USA
| | - James K. Harper
- Department of Chemistry, University of Central Florida, 4104 Libra Drive, Orlando, Florida 32816, USA
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17
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Hartman JD, Neubauer TJ, Caulkins BG, Mueller LJ, Beran GJO. Converging nuclear magnetic shielding calculations with respect to basis and system size in protein systems. JOURNAL OF BIOMOLECULAR NMR 2015; 62:327-40. [PMID: 25993979 PMCID: PMC4512207 DOI: 10.1007/s10858-015-9947-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 05/12/2015] [Indexed: 05/25/2023]
Abstract
Ab initio chemical shielding calculations greatly facilitate the interpretation of nuclear magnetic resonance (NMR) chemical shifts in biological systems, but the large sizes of these systems requires approximations in the chemical models used to represent them. Achieving good convergence in the predicted chemical shieldings is necessary before one can unravel how other complex structural and dynamical factors affect the NMR measurements. Here, we investigate how to balance trade-offs between using a better basis set or a larger cluster model for predicting the chemical shieldings of the substrates in two representative examples of protein-substrate systems involving different domains in tryptophan synthase: the N-(4'-trifluoromethoxybenzoyl)-2-aminoethyl phosphate (F9) ligand which binds in the α active site, and the 2-aminophenol quinonoid intermediate formed in the β active site. We first demonstrate that a chemically intuitive three-layer, locally dense basis model that uses a large basis on the substrate, a medium triple-zeta basis to describe its hydrogen-bonding partners and/or surrounding van der Waals cavity, and a crude basis set for more distant atoms provides chemical shieldings in good agreement with much more expensive large basis calculations. Second, long-range quantum mechanical interactions are important, and one can accurately estimate them as a small-basis correction to larger-basis calculations on a smaller cluster. The combination of these approaches enables one to perform density functional theory NMR chemical shift calculations in protein systems that are well-converged with respect to both basis set and cluster size.
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Affiliation(s)
- Joshua D. Hartman
- Department of Chemistry, University of California at Riverside, Riverside, CA 92521, Tel.: +1-951-827-7869
| | - Thomas J. Neubauer
- Department of Chemistry, University of California at Riverside, Riverside, CA 92521, Tel.: +1-951-827-7869
| | - Bethany G. Caulkins
- Department of Chemistry, University of California at Riverside, Riverside, CA 92521, Tel.: +1-951-827-7869
| | - Leonard J. Mueller
- Department of Chemistry, University of California at Riverside, Riverside, CA 92521, Tel.: +1-951-827-7869
| | - Gregory J. O. Beran
- Department of Chemistry, University of California at Riverside, Riverside, CA 92521, Tel.: +1-951-827-7869
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Li S, Trébosc J, Lafon O, Zhou L, Shen M, Pourpoint F, Amoureux JP, Deng F. Observation of 1H-13C and 1H-1H proximities in a paramagnetic solid by NMR at high magnetic field under ultra-fast MAS. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2015; 251:36-42. [PMID: 25557861 DOI: 10.1016/j.jmr.2014.11.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 11/28/2014] [Accepted: 11/30/2014] [Indexed: 06/04/2023]
Abstract
The assignment of NMR signals in paramagnetic solids is often challenging since: (i) the large paramagnetic shifts often mask the diamagnetic shifts specific to the local chemical environment, and (ii) the hyperfine interactions with unpaired electrons broaden the NMR spectra and decrease the coherence lifetime, thus reducing the efficiency of usual homo- and hetero-nuclear NMR correlation experiments. Here we show that the assignment of (1)H and (13)C signals in isotopically unmodified paramagnetic compounds with moderate hyperfine interactions can be facilitated by the use of two two-dimensional (2D) experiments: (i) (1)H-(13)C correlations with (1)H detection and (ii) (1)H-(1)H double-quantum↔single-quantum correlations. These methods are experimentally demonstrated on isotopically unmodified copper (II) complex of l-alanine at high magnetic field (18.8 T) and ultra-fast Magic Angle Spinning (MAS) frequency of 62.5 kHz. Compared to (13)C detection, we show that (1)H detection leads to a 3-fold enhancement in sensitivity for (1)H-(13)C 2D correlation experiments. By combining (1)H-(13)C and (1)H-(1)H 2D correlation experiments with the analysis of (13)C longitudinal relaxation times, we have been able to assign the (1)H and (13)C signals of each l-alanine ligand.
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Affiliation(s)
- Shenhui Li
- National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Julien Trébosc
- Univ. Lille North of France, Unit of Catalysis and Chemistry of Solids (UCCS), CNRS UMR 8181, ENSCL, Univ. Lille 1, Villeneuve d'Ascq 59652, France
| | - Olivier Lafon
- Univ. Lille North of France, Unit of Catalysis and Chemistry of Solids (UCCS), CNRS UMR 8181, ENSCL, Univ. Lille 1, Villeneuve d'Ascq 59652, France.
| | - Lei Zhou
- National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Ming Shen
- Univ. Lille North of France, Unit of Catalysis and Chemistry of Solids (UCCS), CNRS UMR 8181, ENSCL, Univ. Lille 1, Villeneuve d'Ascq 59652, France; Physics Department & Shanghai Key Laboratory of Magnetic Resonance, East China Normal University, Shanghai 200062, China
| | - Frédérique Pourpoint
- Univ. Lille North of France, Unit of Catalysis and Chemistry of Solids (UCCS), CNRS UMR 8181, ENSCL, Univ. Lille 1, Villeneuve d'Ascq 59652, France
| | - Jean-Paul Amoureux
- Univ. Lille North of France, Unit of Catalysis and Chemistry of Solids (UCCS), CNRS UMR 8181, ENSCL, Univ. Lille 1, Villeneuve d'Ascq 59652, France; Physics Department & Shanghai Key Laboratory of Magnetic Resonance, East China Normal University, Shanghai 200062, China.
| | - Feng Deng
- National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China.
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Mueller LJ, Dunn MF. NMR crystallography of enzyme active sites: probing chemically detailed, three-dimensional structure in tryptophan synthase. Acc Chem Res 2013; 46:2008-17. [PMID: 23537227 DOI: 10.1021/ar3003333] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
NMR crystallography--the synergistic combination of X-ray diffraction, solid-state NMR spectroscopy, and computational chemistry--offers unprecedented insight into three-dimensional, chemically detailed structure. Initially, researchers used NMR crystallography to refine diffraction data from organic and inorganic solids. Now we are applying this technique to explore active sites in biomolecules, where it reveals chemically rich detail concerning the interactions between enzyme site residues and the reacting substrate. Researchers cannot achieve this level of detail from X-ray, NMR,or computational methodologies in isolation. For example, typical X-ray crystal structures (1.5-2.5 Å resolution) of enzyme-bound intermediates identify possible hydrogen-bonding interactions between site residues and substrate but do not directly identify the protonation states. Solid-state NMR can provide chemical shifts for selected atoms of enzyme-substrate complexes, but without a larger structural framework in which to interpret them only empirical correlations with local chemical structure are possible. Ab initio calculations and molecular mechanics can build models for enzymatic processes, but they rely on researcher-specified chemical details. Together, however, X-ray diffraction, solid-state NMR spectroscopy, and computational chemistry can provide consistent and testable models for structure and function of enzyme active sites: X-ray crystallography provides a coarse framework upon which scientists can develop models of the active site using computational chemistry; they can then distinguish these models by comparing calculated NMR chemical shifts with the results of solid-state NMR spectroscopy experiments. Conceptually, each technique is a puzzle piece offering a generous view of the big picture. Only when correctly pieced together, however, can they reveal the big picture at the highest possible resolution. In this Account, we detail our first steps in the development of NMR crystallography applied to enzyme catalysis. We begin with a brief introduction to NMR crystallography and then define the process that we have employed to probe the active site in the β-subunit of tryptophan synthase with unprecedented atomic-level resolution. This approach has resulted in a novel structural hypothesis for the protonation state of the quinonoid intermediate in tryptophan synthase and its surprising role in directing the next step in the catalysis of L-Trp formation.
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Affiliation(s)
- Leonard J. Mueller
- Department of Chemistry and ‡Department of Biochemistry, University of California, Riverside, California 92521, United States
| | - Michael F. Dunn
- Department of Chemistry and ‡Department of Biochemistry, University of California, Riverside, California 92521, United States
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20
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Harper JK, Iuliucci R, Gruber M, Kalakewich K. Refining crystal structures with experimental 13C NMR shift tensors and lattice-including electronic structure methods. CrystEngComm 2013. [DOI: 10.1039/c3ce40108a] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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21
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Chierotti MR, Gobetto R. NMR crystallography: the use of dipolar interactions in polymorph and co-crystal investigation. CrystEngComm 2013. [DOI: 10.1039/c3ce41026a] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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22
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Czernek J, Pawlak T, Potrzebowski MJ, Brus J. The comparison of approaches to the solid-state NMR-based structural refinement of vitamin B1 hydrochloride and of its monohydrate. Chem Phys Lett 2013. [DOI: 10.1016/j.cplett.2012.11.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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23
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Takahashi H, Lee D, Dubois L, Bardet M, Hediger S, De Paëpe G. Rapid Natural-Abundance 2D13C-13C Correlation Spectroscopy Using Dynamic Nuclear Polarization Enhanced Solid-State NMR and Matrix-Free Sample Preparation. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201206102] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Takahashi H, Lee D, Dubois L, Bardet M, Hediger S, De Paëpe G. Rapid natural-abundance 2D 13C-13C correlation spectroscopy using dynamic nuclear polarization enhanced solid-state NMR and matrix-free sample preparation. Angew Chem Int Ed Engl 2012; 51:11766-9. [PMID: 23081784 DOI: 10.1002/anie.201206102] [Citation(s) in RCA: 128] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Indexed: 11/11/2022]
Affiliation(s)
- Hiroki Takahashi
- Laboratoire de Chimie Inorganique et Biologique, UMR-E3 CEA/UJF & CNRS, Institut Nanosciences et Cryogénie (CEA/DSM), 38054 Grenoble, France
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25
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Deschamps M, Cadars S, Gilbert E, Azaïs P, Raymundo-Pinero E, Béguin F, Massiot D. A solid-state NMR study of C(70): a model molecule for amorphous carbons. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2012; 42:81-86. [PMID: 22316606 DOI: 10.1016/j.ssnmr.2012.01.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2011] [Revised: 01/08/2012] [Accepted: 01/13/2012] [Indexed: 05/31/2023]
Abstract
We show that natural abundance, solid-state MAS-NMR (13)C INADEQUATE spectra can be recorded for crystallized C(70), using the through-bond J-coupling for the magnetization transfer. The effect of strong J-coupling can be lessened at high magnetic fields, allowing the observation of cross-peaks between close resonances. DFT calculations of the chemical shifts show an excellent agreement with the experimental values. A correlation is observed between the average CCC bond angles and the (13)C chemical shift, offering a way to understand the dispersion of (13)C chemical shifts in nanoporous activated carbons in terms of local deviations from planarity.
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Affiliation(s)
- Michaël Deschamps
- CNRS-CEMHTI, UPR 3079, 1D Avenue de la Recherche Scientifique, 45071 Orléans cedex 2, France.
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26
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Nomura K, Lintuluoto M, Morigaki K. Hydration and temperature dependence of 13C and 1H NMR spectra of the DMPC phospholipid membrane and complete resonance assignment of its crystalline state. J Phys Chem B 2011; 115:14991-5001. [PMID: 22044314 DOI: 10.1021/jp208958a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Inhomogeneous line broadening due to conformational distributions of molecules is one of the troublesome problems in solid-state NMR spectroscopy. The best possible way to avoid it is to crystallize the sample. Here, we present a highly resolved (13)C cross-polarization (CP) magic angle spinning (MAS) NMR spectrum of the highly ordered crystalline 1,2-dimyrystoyl-sn-glycero-3-phosphocholine (DMPC) and completely assigned it using two-dimensional (2D) solid-state NMR spectra, dipolar heteronuclear correlation (HETCOR) spectra, scalar heteronuclear J coupling based chemical shift correlation (MAS-J-HMQC) spectra, and Dipolar Assisted Rotational Resonance (DARR) spectra. A comparison between assigned chemical shift values by solid-state NMR in this study and the calculated chemical shift values for X-ray crystal DMPC structures shows good agreement, indicating that the two isomers in the crystalline DMPC take the same conformation as the X-ray crystal structure. The phase diagram of the low hydration level of DMPC (3 ≤ n(W) ≤ 12) determined by (1)H and (13)C NMR spectra indicates that DMPC takes a crystalline state only in a very narrow region around n(W) = 4 and T < 313 K. These findings provide us with conformational information on crystalline DMPC and the physical properties of DMPC at a low hydration level and can possibly help us obtain a highly resolved solid-state NMR spectrum of microcrystalline membrane-associated protein samples.
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Affiliation(s)
- Kaoru Nomura
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Mishima-Gun, Osaka, Japan.
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27
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Webber AL, Emsley L, Claramunt RM, Brown SP. NMR crystallography of campho[2,3-c]pyrazole (Z' = 6): combining high-resolution 1H-13C solid-state MAS NMR spectroscopy and GIPAW chemical-shift calculations. J Phys Chem A 2011; 114:10435-42. [PMID: 20815383 DOI: 10.1021/jp104901j] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
(1)H-(13)C two-dimensional magic-angle spinning (MAS) solid-state NMR correlation spectra, recorded with the MAS-J-HMQC experiment, are presented for campho[2,3-c]pyrazole. For each (13)C moiety, there are six resonances associated with the six distinct molecules in the asymmetric unit cell (Z' = 6). The one-bond C-H correlations observed in the 2D (1)H-(13)C MAS-J-HMQC spectra allow the experimental determination of the (1)H and (13)C chemical shifts associated with the separate CH, CH(2), and CH(3) groups. (1)H and (13)C chemical shifts calculated by using the GIPAW (Gauge Including Projector Augmented Waves) plane-wave pseudopotential approach are presented. Calculations for the whole unit cell (12 × 29 = 348 atoms, with geometry optimization of all atoms) allow the assignment of the experimental (1)H and (13)C chemical shifts to the six distinct molecules. The calculated chemical shifts for the full crystal structure are compared with those for isolated molecules as extracted from the geometry-optimized crystal structure. In this way, the effect of intermolecular interactions on the observed chemical shifts is quantified. In particular, the calculations are sufficiently precise to differentiate the small (<1 ppm) differences between the (1)H chemical shifts of the six resonances associated with each distinct CH or CH(2) moiety.
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Affiliation(s)
- Amy L Webber
- Department of Physics, University of Warwick, Coventry CV4 7AL, UK
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28
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Lai J, Niks D, Wang Y, Domratcheva T, Barends TRM, Schwarz F, Olsen RA, Elliott DW, Fatmi MQ, Chang CEA, Schlichting I, Dunn MF, Mueller LJ. X-ray and NMR Crystallography in an Enzyme Active Site: The Indoline Quinonoid Intermediate in Tryptophan Synthase. J Am Chem Soc 2010; 133:4-7. [DOI: 10.1021/ja106555c] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jinfeng Lai
- Departments of Chemistry and Biochemistry, University of California, Riverside, California 92521, United States, and Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - Dimitri Niks
- Departments of Chemistry and Biochemistry, University of California, Riverside, California 92521, United States, and Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - Yachong Wang
- Departments of Chemistry and Biochemistry, University of California, Riverside, California 92521, United States, and Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - Tatiana Domratcheva
- Departments of Chemistry and Biochemistry, University of California, Riverside, California 92521, United States, and Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - Thomas R. M. Barends
- Departments of Chemistry and Biochemistry, University of California, Riverside, California 92521, United States, and Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - Friedrich Schwarz
- Departments of Chemistry and Biochemistry, University of California, Riverside, California 92521, United States, and Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - Ryan A. Olsen
- Departments of Chemistry and Biochemistry, University of California, Riverside, California 92521, United States, and Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - Douglas W. Elliott
- Departments of Chemistry and Biochemistry, University of California, Riverside, California 92521, United States, and Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - M. Qaiser Fatmi
- Departments of Chemistry and Biochemistry, University of California, Riverside, California 92521, United States, and Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - Chia-en A. Chang
- Departments of Chemistry and Biochemistry, University of California, Riverside, California 92521, United States, and Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - Ilme Schlichting
- Departments of Chemistry and Biochemistry, University of California, Riverside, California 92521, United States, and Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - Michael F. Dunn
- Departments of Chemistry and Biochemistry, University of California, Riverside, California 92521, United States, and Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
| | - Leonard J. Mueller
- Departments of Chemistry and Biochemistry, University of California, Riverside, California 92521, United States, and Department of Biomolecular Mechanisms, Max Planck Institute for Medical Research, 69120 Heidelberg, Germany
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29
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Bryce DL. A computational investigation of J couplings involving ²⁷Al, ¹⁷O, and ³¹P. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2010; 48 Suppl 1:S69-S75. [PMID: 20589723 DOI: 10.1002/mrc.2630] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Indirect nuclear spin-spin (J) couplings between (31)P, (27)Al, and (17)O are computed for Cl(3)POAlCl(3), Ph(3)PO, Ph(3)PAlCl(3), Al(H(2)O)(6)(3+), an aluminophosphate model system, and grossite model systems, using the B3LYP hybrid functional and the pcJ-n and aug-pcJ-n basis sets. The results provide computational corroboration of the existence of J coupling constants between (31)P, (17)O, and (27)Al of suitable magnitude for INEPT-style experiments in which connectivity is established as a result of magnetization transfer using these couplings. Potentially useful correlations between structure (bond lengths, angles, dihedrals) and the coupling constants (1)J((27)Al, (17)O), (1)J((31)P, (17)O), and (2)J((31)P, (27)Al) are presented. Calculated values of near zero for both (1)J((27)Al, (17)O) and (2)J((31)P, (27)Al), depending on the molecule and the geometry, suggest that some structurally important correlations could be absent in NMR spectra which rely on magnetization transfers solely based on these isotropic coupling constants.
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Affiliation(s)
- David L Bryce
- Department of Chemistry and Centre for Catalysis Research and Innovation, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada.
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30
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Webber AL, Elena B, Griffin JM, Yates JR, Pham TN, Mauri F, Pickard CJ, Gil AM, Stein R, Lesage A, Emsley L, Brown SP. Complete (1)H resonance assignment of beta-maltose from (1)H-(1)H DQ-SQ CRAMPS and (1)H (DQ-DUMBO)-(13)C SQ refocused INEPT 2D solid-state NMR spectra and first principles GIPAW calculations. Phys Chem Chem Phys 2010; 12:6970-83. [PMID: 20480118 DOI: 10.1039/c001290d] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A disaccharide is a challenging case for high-resolution (1)H solid-state NMR because of the 24 distinct protons (14 aliphatic and 10 OH) having (1)H chemical shifts that all fall within a narrow range of approximately 3 to 7 ppm. High-resolution (1)H (500 MHz) double-quantum (DQ) combined rotation and multiple pulse sequence (CRAMPS) solid-state NMR spectra of beta-maltose monohydrate are presented. (1)H-(1)H DQ-SQ CRAMPS spectra are presented together with (1)H (DQ)-(13)C correlation spectra obtained with a new pulse sequence that correlates a high-resolution (1)H DQ dimension with a (13)C single quantum (SQ) dimension using the refocused INEPT pulse-sequence element to transfer magnetization via one-bond (13)C-(1)H J couplings. Compared to the observation of only a single broad peak in a (1)H DQ spectrum recorded at 30 kHz magic-angle spinning (MAS), the use of DUMBO (1)H homonuclear decoupling in the (1)H DQ CRAMPS experiment allows the resolution of distinct DQ correlation peaks which, in combination with first-principles chemical shift calculations based on the GIPAW (Gauge Including Projector Augmented Waves) plane-wave pseudopotential approach, enables the assignment of the (1)H resonances to the 24 distinct protons. We believe this to be the first experimental solid-state NMR determination of the hydroxyl OH (1)H chemical shifts for a simple sugar. Variable-temperature (1)H-(1)H DQ CRAMPS spectra reveal small increases in the (1)H chemical shifts of the OH resonances upon decreasing the temperature from 348 K to 248 K.
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Affiliation(s)
- Amy L Webber
- Department of Physics, University of Warwick, Coventry, CV4 7AL, UK
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31
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Johnston JC, Iuliucci RJ, Facelli JC, Fitzgerald G, Mueller KT. Intermolecular shielding contributions studied by modeling the (13)C chemical-shift tensors of organic single crystals with plane waves. J Chem Phys 2009; 131:144503. [PMID: 19831448 PMCID: PMC2771050 DOI: 10.1063/1.3225270] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2009] [Accepted: 08/17/2009] [Indexed: 11/14/2022] Open
Abstract
In order to predict accurately the chemical shift of NMR-active nuclei in solid phase systems, magnetic shielding calculations must be capable of considering the complete lattice structure. Here we assess the accuracy of the density functional theory gauge-including projector augmented wave method, which uses pseudopotentials to approximate the nodal structure of the core electrons, to determine the magnetic properties of crystals by predicting the full chemical-shift tensors of all (13)C nuclides in 14 organic single crystals from which experimental tensors have previously been reported. Plane-wave methods use periodic boundary conditions to incorporate the lattice structure, providing a substantial improvement for modeling the chemical shifts in hydrogen-bonded systems. Principal tensor components can now be predicted to an accuracy that approaches the typical experimental uncertainty. Moreover, methods that include the full solid-phase structure enable geometry optimizations to be performed on the input structures prior to calculation of the shielding. Improvement after optimization is noted here even when neutron diffraction data are used for determining the initial structures. After geometry optimization, the isotropic shift can be predicted to within 1 ppm.
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Affiliation(s)
- Jessica C Johnston
- Department of Chemistry, Washington and Jefferson College, Washington, Pennsylvania 15301, USA
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32
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Mousavi M, Yu SSF, Tzou DLM. A (13)C solid-state NMR analysis of vitamin D compounds. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2009; 36:24-31. [PMID: 19493660 DOI: 10.1016/j.ssnmr.2009.04.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2009] [Revised: 03/25/2009] [Accepted: 04/22/2009] [Indexed: 05/27/2023]
Abstract
(13)C cross-polarization/magic-angle spinning (CP/MAS) solid-state NMR spectroscopy has been employed to analyze four vitamin D compounds, namely vitamin D3 (D3), vitamin D2 (D2), and the precursors ergosterol (Erg) and 7-dehydrocholesterol (7DHC). The (13)C NMR spectrum of D3 displays a doublet pattern for each of the carbon atoms, while that of Erg contains both singlet and doublet patterns. In the cases of 7DHC and D2, the (13)C spectra display various multiplet patterns, viz. singlets, doublets, triplets, and quartets. To overcome the signal overlap between the (13)C resonances of protonated and unprotonated carbons, we have subjected these vitamin D compounds to 1D (1)H-filtered (13)C CP/MAS and {(1)H}/(13)C heteronuclear correlation (Hetcor) NMR experiments. As a result, assisted by solution NMR data, all of the (13)C resonances have been successfully assigned to the respective carbon atoms of these vitamin D compounds. The (13)C multiplets are interpreted due to the presence of s-cis and s-trans configurations in the alpha- and beta-molecular conformers, consistent with computer molecular modeling determined by molecular dynamics and energy minimization calculations. To further characterize the ring conformations in D3, we have successfully extracted chemical shift tensor elements for the (13)C doublets. It is demonstrated that (13)C solid-state NMR spectroscopy provides a robust and high sensitive means of characterizing molecular conformations in vitamin D compounds.
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Affiliation(s)
- Mansoureh Mousavi
- Institute of Chemistry, Academia Sinica, Nankang, Taipei 11529, Taiwan, ROC
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33
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Molecular structure of actein: 13C CPMAS NMR, IR, X-ray diffraction studies and theoretical DFT–GIAO calculations. J Mol Struct 2009. [DOI: 10.1016/j.molstruc.2009.06.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Tian Y, Chen L, Niks D, Kaiser JM, Lai J, Rienstra CM, Dunn MF, Mueller LJ. J-Based 3D sidechain correlation in solid-state proteins. Phys Chem Chem Phys 2009; 11:7078-86. [PMID: 19652843 PMCID: PMC2798598 DOI: 10.1039/b911570f] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Scalar-based three-dimensional homonuclear correlation experiments are reported for (13)C sidechain correlation in solid-state proteins. These experiments are based on a sensitive constant-time format, in which homonuclear scalar couplings are utilized for polarization transfer, but decoupled during chemical shift evolution, to yield highly resolved indirect dimensions and band selectivity as desired. The methods therefore yield spectra of high quality that give unique sets of sidechain correlations for small proteins even at 9.4 Tesla (400 MHz (1)H frequency). We demonstrate versions of the pulse sequence that enable correlation from the sidechain to the backbone carbonyl as well as purely sidechain correlation sets; together these two data sets provide the majority of (13)C-(13)C correlations for assignment. The polarization transfer efficiency is approximately 30% over two bonds. In the protein GB1 (56 residues), we find essentially all cross peaks uniquely resolved. We find similar efficiency of transfer (approximately 30%) in the 140 kDa tryptophan synthase (TS), since the relaxation rates of immobilized solid proteins are not sensitive to global molecular tumbling, as long as the correlation time is much longer than the magic-angle spinning rotor period. In 3D data sets of TS at 400 MHz, some peaks are resolved and, in combination with higher field data sets, we anticipate that assignments will be possible; in this vein, we demonstrate 2D (13)C-(13)C spectra of TS at 900 MHz that are well resolved. These results together provide optimism about the prospects for assigning the spectra of such large enzymes in the solid state.
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Affiliation(s)
- Ye Tian
- Department of Chemistry, University of California, Riverside, California 92521
| | - Lingling Chen
- Department of Chemistry, University of California, Riverside, California 92521
| | - Dimitri Niks
- Department of Biochemistry, University of California, Riverside, California 92521
| | - J. Michael Kaiser
- Department of Chemistry, University of California, Riverside, California 92521
| | - Jinfeng Lai
- Department of Chemistry, University of California, Riverside, California 92521
| | - Chad M. Rienstra
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801
| | - Michael F. Dunn
- Department of Biochemistry, University of California, Riverside, California 92521
| | - Leonard J. Mueller
- Department of Chemistry, University of California, Riverside, California 92521
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35
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Brown SP. Recent Advances in Solid-State MAS NMR Methodology for Probing Structure and Dynamics in Polymeric and Supramolecular Systems. Macromol Rapid Commun 2009; 30:688-716. [DOI: 10.1002/marc.200800816] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2008] [Accepted: 02/06/2009] [Indexed: 01/12/2023]
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36
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Lee D, Struppe J, Elliott DW, Mueller LJ, Titman JJ. Sensitive absorptive refocused scalar correlation NMR spectroscopy in solids. Phys Chem Chem Phys 2009; 11:3547-53. [PMID: 19421560 DOI: 10.1039/b818867j] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new two-dimensional NMR experiment is described which is suitable for obtaining magic angle spinning (MAS) scalar correlation spectra in solids. The new experiment has several advantages, including increased cross peak intensities, coupled with good suppression of the diagonal. Its utility is demonstrated via assignments of the carbon-13 MAS spectra of progesterone at natural abundance and of the polymer phase of 50%-U-13C-CsC60.
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Affiliation(s)
- Daniel Lee
- School of Chemistry, University of Nottingham, University Park, Nottingham, UK NG7 2RD
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Lesage A. Recent advances in solid-state NMR spectroscopy of spin I = 1/2 nuclei. Phys Chem Chem Phys 2009; 11:6876-91. [DOI: 10.1039/b907733m] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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38
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Brouwer DH. A structure refinement strategy for NMR crystallography: an improved crystal structure of silica-ZSM-12 zeolite from 29Si chemical shift tensors. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2008; 194:136-146. [PMID: 18656402 DOI: 10.1016/j.jmr.2008.06.020] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2008] [Revised: 06/26/2008] [Accepted: 06/26/2008] [Indexed: 05/26/2023]
Abstract
A strategy for performing crystal structure refinements with NMR chemical shift tensors is described in detail and implemented for the zeolite silica-ZSM-12 (framework type code MTW). The 29Si chemical shift tensors were determined from a slow magic-angle spinning spectrum obtained at an ultrahigh magnetic field of 21.1T. The Si and O atomic coordinate parameters were optimized to give the best agreement between experimentally measured and ab initio calculated principal components of the 29Si chemical shift tensors, with the closest Si-O, O-O, and Si-Si distances restrained to correspond with the distributions of the distances found in a set of single-crystal X-ray diffraction (XRD) structures of high-silica zeolites. An improved structure for the silica-ZSM-12 zeolite, compared to a prior structure derived from powder XRD data, is obtained in which the agreement between the experimental and calculated 29Si chemical shift tensors is dramatically improved, the Si-O, O-O, and Si-Si distances correspond to the expected distributions, while the calculated powder XRD pattern remains in good agreement with the experimental powder XRD data. It is anticipated that this "NMR crystallography" structure refinement strategy will be an important tool for the accurate structure determination of materials that are difficult to fully characterize by traditional diffraction methods.
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Affiliation(s)
- Darren H Brouwer
- Steacie Institute for Molecular Science, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ont., Canada.
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39
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Harris RK, Hodgkinson P, Pickard CJ, Yates JR, Zorin V. Chemical shift computations on a crystallographic basis: some reflections and comments. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2007; 45 Suppl 1:S174-S186. [PMID: 18157842 DOI: 10.1002/mrc.2132] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Computations for chemical shifts of molecular organic compounds using the gauge-including projector augmented wave method and the NMR-CASTEP code are reviewed. The methods are briefly introduced, and some general aspects involving the sources of uncertainty in the results are explored. The limitations are outlined. Successful applications of the computations to problems of interpretation of NMR results are discussed and the range of areas in which useful information is obtained is illustrated by examples. The particular value of the computations for comparing shifts between resonances where the same chemical site is involved is emphasised. Such cases arise for shifts between different crystallographically independent molecules of the same chemical species, between polymorphs and for shift anisotropies and asymmetries.
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Affiliation(s)
- Robin K Harris
- Department of Chemistry, University of Durham, South Road, Durham DH1 3LE, UK.
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40
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Chen L, Kaiser JM, Lai J, Polenova T, Yang J, Rienstra CM, Mueller LJ. J-based 2D homonuclear and heteronuclear correlation in solid-state proteins. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2007; 45 Suppl 1:S84-S92. [PMID: 18157839 DOI: 10.1002/mrc.2107] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Scalar-based two-dimensional heteronuclear experiments are reported for NCO and NCA chemical shift correlation in the solid state. In conjunction with homonuclear CACO correlation, these experiments form a useful set for tracing connectivities and assigning backbone resonances in solid-state proteins. The applicability of this approach is demonstrated on two proteins, the β 1 immunoglobulin binding domain of protein G at 9.4 T and reassembled thioredoxin at 14.1 T, using different decoupling conditions and MAS frequencies. These constant-time J-based correlation experiments exhibit increased resolution in the indirect dimension owing to homonuclear and heteronuclear decoupling, and because the indirect evolution and transfer periods are combined into a single constant time interval, this increased resolution is not obtained at the cost of sensitivity. These experiments are also shown to be compatible with in-phase anti-phase (IPAP) selection, giving increased resolution in the directly detected dimension.
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Affiliation(s)
- Lingling Chen
- Department of Chemistry, University of California, Riverside, California 92521, USA
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41
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Harper JK, Strohmeier M, Grant DM. Pursuing structure in microcrystalline solids with independent molecules in the unit cell using 1H-13C correlation data. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2007; 189:20-31. [PMID: 17869558 PMCID: PMC2819409 DOI: 10.1016/j.jmr.2007.06.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2007] [Accepted: 06/23/2007] [Indexed: 05/14/2023]
Abstract
The (1)H-(13)C solid-state NMR heteronuclear correlation (HETCOR) experiment is demonstrated to provide shift assignments in certain powders that have two or more structurally independent molecules in the unit cell (i.e. multiple molecules per asymmetric unit). Although this class of solids is often difficult to characterize using other methods, HETCOR provides both the conventional assignment of shifts to molecular positions and associates many resonances with specific molecules in the asymmetric unit. Such assignments facilitate conformational characterization of the individual molecules of the asymmetric unit and the first such characterization solely from solid-state NMR data is described. HETCOR offers advantages in sensitivity over prior methods that assign resonances in the asymmetric unit by (13)C-(13)C correlations and therefore allows shorter average analysis times in natural abundance materials. The (1)H-(13)C analysis is demonstrated first on materials with known shift assignments from INADEQUATE data (santonin and Ca(OAc)(2) phase I) to verify the technique and subsequently is extended to a pair of unknown solids: (+)-catechin and Ca(OAc)(2) phase II. Sufficient sensitivity and resolution is achieved in the spectra to provide assignments to one of the specific molecules of the asymmetric unit at over 54% of the sites.
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Affiliation(s)
- James K. Harper
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, UT 84112, USA
| | - Mark Strohmeier
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, UT 84112, USA
| | - David M. Grant
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, UT 84112, USA
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42
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Heider EM, Harper JK, Grant DM. Structural characterization of an anhydrous polymorph of paclitaxel by solid-state NMR. Phys Chem Chem Phys 2007; 9:6083-97. [PMID: 18167583 DOI: 10.1039/b711027h] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The three-dimensional structure of a unique polymorph of the anticancer drug paclitaxel (Taxol) is established using solid state NMR (SSNMR) tensor ((13)C & (15)N) and heteronuclear correlation ((1)H-(13)C) data. The polymorph has two molecules per asymmetric unit (Z' = 2) and is thus the first conformational characterization with Z' > 1 established solely by SSNMR. Experimental data are correlated with structure through a series of computational models that extensively sample all conformations. For each computational model, corresponding tensor values are computed to supply comparisons with experimental information which, in turn, establishes paclitaxel's structure. Heteronuclear correlation data at thirteen key positions provide shift assignments to the asymmetric unit for each comparison. The two distinct molecules of the asymmetric unit possess nearly identical baccatin III moieties with matching conformations of the C10 acetyl moiety and, specifically, the torsion angle formed by C30-O-C10-C9. Additionally, both are found to exhibit an extended conformation of the phenylisoserine sidechain at C13 with notable differences in the dihedral angles centered around the rotation axes of O-C13, C2'-C1' and C3'-C2'.
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Affiliation(s)
- Elizabeth M Heider
- Department of Physics and Astronomy, Tufts University, Medford, MA 02155, USA
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43
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Cadars S, Sein J, Duma L, Lesage A, Pham TN, Baltisberger JH, Brown SP, Emsley L. The refocused INADEQUATE MAS NMR experiment in multiple spin-systems: interpreting observed correlation peaks and optimising lineshapes. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2007; 188:24-34. [PMID: 17588789 DOI: 10.1016/j.jmr.2007.05.016] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2007] [Accepted: 05/18/2007] [Indexed: 05/12/2023]
Abstract
The robustness of the refocused INADEQUATE MAS NMR pulse sequence for probing through-bond connectivities has been demonstrated in a large range of solid-state applications. This pulse sequence nevertheless suffers from artifacts when applied to multispin systems, e.g. uniformly labeled (13)C solids, which distort the lineshapes and can potentially result in misleading correlation peaks. In this paper, we present a detailed account that combines product-operator analysis, numerical simulations and experiments of the behavior of a three-spin system during the refocused INADEQUATE pulse sequence. The origin of undesired anti-phase contributions to the spectral lineshapes are described, and we show that they do not interfere with the observation of long-range correlations (e.g. two-bond (13)C-(13)C correlations). The suppression of undesired contributions to the refocused INADEQUATE spectra is shown to require the removal of zero-quantum coherences within a z-filter. A method is proposed to eliminate zero-quantum coherences through dephasing by heteronuclear dipolar couplings, which leads to pure in-phase spectra.
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Affiliation(s)
- Sylvian Cadars
- Laboratoire de Chimie (UMR 5182 CNRS/ENS Lyon), Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364 Lyon Cedex 07, France
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44
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Pickard CJ, Salager E, Pintacuda G, Elena B, Emsley L. Resolving Structures from Powders by NMR Crystallography Using Combined Proton Spin Diffusion and Plane Wave DFT Calculations. J Am Chem Soc 2007; 129:8932-3. [PMID: 17602560 DOI: 10.1021/ja071829h] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Chris J Pickard
- Laboratoire de Chimie (UMR 5182 CNRS/ENS), Ecole Normale Supérieure de Lyon, 69364 Lyon, France
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45
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Mifsud N, Elena B, Pickard CJ, Lesage A, Emsley L. Assigning powders to crystal structures by high-resolution (1)H-(1)H double quantum and (1)H-(13)C J-INEPT solid-state NMR spectroscopy and first principles computation. A case study of penicillin G. Phys Chem Chem Phys 2006; 8:3418-22. [PMID: 16855720 DOI: 10.1039/b605227d] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We show how powder samples at natural isotopic abundance can be assigned to crystal structures by using high-resolution proton and carbon-13 solid-state NMR spectra in combination with first principles calculations. Homonuclear proton double-quantum spectra in combination with through-bond proton-carbon HSQC spectra are used to assign the NMR spectra. We then show that the proton chemical shifts can be included in the process of assigning the spectra to a crystal structure using first principles calculations. The method is demonstrated on the K salt of penicillin G.
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Affiliation(s)
- Nicolas Mifsud
- Laboratoire de Chimie (UMR 5182 ENS/CNRS), Laboratoire de Recherche Conventionné du CEA (DSV 23V/DSM 0432), Ecole Normale Supérieure de Lyon, 46, Allée d'Italie, 69364 Lyon, France
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46
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Fayon F, Roiland C, Emsley L, Massiot D. Triple-quantum correlation NMR experiments in solids using J-couplings. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2006; 179:49-57. [PMID: 16307897 DOI: 10.1016/j.jmr.2005.11.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2005] [Revised: 11/03/2005] [Accepted: 11/03/2005] [Indexed: 05/05/2023]
Abstract
We show that triple-quantum-single-quantum (TQ-SQ) correlation spectra of crystalline and disordered solids can be obtained under MAS using pulse sequences based on through-bond J-couplings. The feasibility of the experiments in coupled spin-1/2 systems is demonstrated for fully 13C-labelled L-alanine and Pb3P4O13 crystalline compounds, considered as model three-spin and four-spin systems, respectively. In the case of phosphate glasses, we show that the obtained TQ-SQ correlation spectra provide an improved description of the glass forming network connectivities and of the chain length distribution in the disordered network.
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Affiliation(s)
- Franck Fayon
- Centre de Recherches sur les Matériaux à Haute Température, CNRS, 45071 Orléans cedex 2, France.
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47
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Harris RK, Joyce SA, Pickard CJ, Cadars S, Emsley L. Assigning carbon-13 NMR spectra to crystal structures by the INADEQUATE pulse sequence and first principles computation: a case study of two forms of testosterone. Phys Chem Chem Phys 2005; 8:137-43. [PMID: 16482253 DOI: 10.1039/b513392k] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A (13)C CPMAS NMR experiment at high field (11.7 T) has produced significantly improved dispersion for the alpha form of testosterone, allowing revisions and extensions to be made to the assignments. Correlations shown by an INADEQUATE two-dimensional spectrum, recorded at 16.5 T, have allowed the components of most of the doublet signals to be grouped into two sets (for the two crystallographically independent molecules). First-principles computations, employing a fully solid-state approach, have been used to obtain values for the crystallographic splittings, which are discussed in relation to the experimental values. This procedure enables assignments to the two groups to be suggested for all but one of the remaining doublet signals. It also allows the two sets of signals to be identified specifically to the two independent molecules in the crystal structure. Computations were also carried out for the beta form of testosterone (a dihydrate). The shift differences between the alpha and beta forms were compared with the experimental data, with encouraging results. Comparisons were also made between computed and experimental shielding anisotropies and asymmetries for three of the carbons of the alpha form. The methodology has a high potential for future applications, though more examples need to be evaluated before general conclusions can be drawn.
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Affiliation(s)
- Robin K Harris
- Department of Chemistry, University of Durham, South Road, Durham DH1 3LE, UK.
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48
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Fayon F, Massiot D, Levitt MH, Titman JJ, Gregory DH, Duma L, Emsley L, Brown SP. Through-space contributions to two-dimensional double-quantum J correlation NMR spectra of magic-angle-spinning solids. J Chem Phys 2005; 122:194313. [PMID: 16161579 DOI: 10.1063/1.1898219] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
A routinely used assumption when interpreting two-dimensional NMR spectra obtained with a commonly used double-quantum (DQ) magic-angle-spining (MAS) pulse sequence referred to as the refocused incredible natural abundance double-quantum transfer experiment (INADEQUATE) [A. Lesage, M. Bardet, and L. Emsley, J. Am. Chem. Soc. 121, 10987 (1999)] has been that correlation peaks are only observed for pairs of nuclei with a through-bond connectivity. The validity of this assumption is addressed here by theory, experiment, and computer simulations. If the isotropic chemical shifts of the two nuclei are different and the MAS frequency is far from rotational resonance, the theoretical description demonstrates that DQ correlation peaks are indeed indicative of a J coupling. However, if the isotropic chemical shifts are the same, it is shown that DQ peaks can appear for pairs of nuclei even in the absence of a through-bond J coupling. These peaks appear in the specific case of a pair of nuclei with a nonzero through-space dipole-dipole coupling and chemical shift anisotropy tensors having different principal magnitudes or orientations, provided that the MAS frequency is comparable to or smaller than the chemical shift anisotropies. Experimental 31P spectra recorded on a sample of TiP2O7 and computer simulations show that the magnitude of these anomalous peaks increases with increasing B0 magnetic field and that they decrease with increasing MAS frequency. This behavior is explained theoretically.
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Affiliation(s)
- Franck Fayon
- Centre de Recherches sur les Matériaux à Haute Température, Centre National de la Recherche Scientifique (CNRS), 45071 Orléans Cedex 2, France
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49
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Mueller LJ, Elliott DW, Leskowitz GM, Struppe J, Olsen RA, Kim KC, Reed CA. Uniform-sign cross-peak double-quantum-filtered correlation spectroscopy. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2004; 168:327-335. [PMID: 15140444 DOI: 10.1016/j.jmr.2004.03.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2003] [Revised: 03/18/2004] [Indexed: 05/24/2023]
Abstract
We detail the uniform-sign cross-peak double-quantum-filtered correlation spectroscopy (UC2QF COSY) experiment, a new through-bond correlation method for disordered solids. This experiment is a refocused version of the popular double-quantum-filtered correlation spectroscopy experiment in liquids. Its key feature is that it provides in-phase and doubly absorptive line shapes, which renders it robust for chemical shift correlation in solids. Both theory and experiment point to distinct advantages of this protocol, which are illustrated by several experiments under challenging conditions, including fast magic-angle spinning (30kHz), anisotropic molecular motion, and (13)C correlation spectroscopy at the natural abundance isotope level.
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Affiliation(s)
- Leonard J Mueller
- Department of Chemistry, University of California, Riverside, CA 92521, USA.
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50
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Brus J, Jegorov A. Through-Bonds and Through-Space Solid-State NMR Correlations at Natural Isotopic Abundance: Signal Assignment and Structural Study of Simvastatin. J Phys Chem A 2004. [DOI: 10.1021/jp0498163] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jiri Brus
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovsky sq. 2, 162 06 Prague 6, Czech Republic, and IVAX Pharmaceutical sro, Research Unit, Branisovska 31, 370 05 Ceske Budejovice, Czech Republic
| | - Alexandr Jegorov
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovsky sq. 2, 162 06 Prague 6, Czech Republic, and IVAX Pharmaceutical sro, Research Unit, Branisovska 31, 370 05 Ceske Budejovice, Czech Republic
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