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Erastova V, Evans IR, Glossop WN, Guryel S, Hodgkinson P, Kerr HE, Oganesyan VS, Softley LK, Wickins HM, Wilson MR. Unravelling Guest Dynamics in Crystalline Molecular Organics Using 2H Solid-State NMR and Molecular Dynamics Simulation. J Am Chem Soc 2024; 146:18360-18369. [PMID: 38935813 PMCID: PMC11240262 DOI: 10.1021/jacs.4c03246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 05/30/2024] [Accepted: 05/30/2024] [Indexed: 06/29/2024]
Abstract
2H solid-state NMR and atomistic molecular dynamics (MD) simulations are used to understand the disorder of guest solvent molecules in two cocrystal solvates of the pharmaceutical furosemide. Traditional approaches to interpreting the NMR data fail to provide a coherent model of molecular behavior and indeed give misleading kinetic data. In contrast, the direct prediction of the NMR properties from MD simulation trajectories allows the NMR data to be correctly interpreted in terms of combined jump-type and libration-type motions. Time-independent component analysis of the MD trajectories provides additional insights, particularly for motions that are invisible to NMR. This allows a coherent picture of the dynamics of molecules restricted in molecular-sized cavities to be determined.
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Affiliation(s)
- Valentina Erastova
- Department
of Chemistry, Durham University, Stockton Road, Durham DH1 3LE, U.K.
- Department
of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster
Road, Edinburgh EH9 3FJ, U.K.
| | - Ivana R. Evans
- Department
of Chemistry, Durham University, Stockton Road, Durham DH1 3LE, U.K.
| | - William N. Glossop
- Department
of Chemistry, Durham University, Stockton Road, Durham DH1 3LE, U.K.
| | - Songül Guryel
- Department
of Chemistry, Durham University, Stockton Road, Durham DH1 3LE, U.K.
| | - Paul Hodgkinson
- Department
of Chemistry, Durham University, Stockton Road, Durham DH1 3LE, U.K.
| | - Hannah E. Kerr
- Department
of Chemistry, Durham University, Stockton Road, Durham DH1 3LE, U.K.
| | | | - Lorna K. Softley
- Department
of Chemistry, Durham University, Stockton Road, Durham DH1 3LE, U.K.
| | - Helen M. Wickins
- Department
of Chemistry, Durham University, Stockton Road, Durham DH1 3LE, U.K.
| | - Mark R. Wilson
- Department
of Chemistry, Durham University, Stockton Road, Durham DH1 3LE, U.K.
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2
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Vugmeyster L, Ostrovsky D, Fu R. Carbon-detected deuterium solid-state NMR rotating frame relaxation measurements for protein methyl groups under magic angle spinning. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2024; 130:101922. [PMID: 38417233 PMCID: PMC11015826 DOI: 10.1016/j.ssnmr.2024.101922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 02/16/2024] [Accepted: 02/20/2024] [Indexed: 03/01/2024]
Abstract
Deuterium rotating frame solid-state NMR relaxation measurements (2H R1ρ) are important tools in quantitative studies of molecular dynamics. We demonstrate how 2H to 13C cross-polarization (CP) approaches under 10-40 kHz magic angle spinning rates can be combined with the 2H R1ρ blocks to allow for extension of deuterium rotating frame relaxation studies to methyl groups in biomolecules. This extension permits detection on the 13C nuclei and, hence, for the achievement of site-specific resolution. The measurements are demonstrated using a nine-residue low complexity peptide with the sequence GGKGMGFGL, in which a single selective -13CD3 label is placed at the methionine residue. Carbon-detected measurements are compared with the deuterium direct-detection results, which allows for fine-tuning of experimental approaches. In particular, we show how the adiabatic respiration CP scheme and the double adiabatic sweep on the 2H and 13C channels can be combined with the 2H R1ρ relaxation rates measurement. Off-resonance 2H R1ρ measurements are investigated in addition to the on-resonance condition, as they extent the range of effective spin-locking field.
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Affiliation(s)
- Liliya Vugmeyster
- Department of Chemistry, University of Colorado Denver, Denver, CO, 80204, USA.
| | - Dmitry Ostrovsky
- Department of Mathematics, University of Colorado Denver, Denver, CO, 80204, USA
| | - Riqiang Fu
- National High Field Magnetic Laboratory, Tallahassee, FL, 32310, USA
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3
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Vugmeyster L, Ostrovsky D, Rodgers A, Gwin K, Smirnov SL, McKnight CJ, Fu R. Persistence of Methionine Side Chain Mobility at Low Temperatures in a Nine-Residue Low Complexity Peptide, as Probed by 2 H Solid-State NMR. Chemphyschem 2024; 25:e202300565. [PMID: 38175858 PMCID: PMC10922872 DOI: 10.1002/cphc.202300565] [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: 08/09/2023] [Revised: 12/01/2023] [Indexed: 01/06/2024]
Abstract
Methionine side chains are flexible entities which play important roles in defining hydrophobic interfaces. We utilize deuterium static solid-state NMR to assess rotameric inter-conversions and other dynamic modes of the methionine in the context of a nine-residue random-coil peptide (RC9) with the low-complexity sequence GGKGMGFGL. The measurements in the temperature range of 313 to 161 K demonstrate that the rotameric interconversions in the hydrated solid powder state persist to temperatures below 200 K. Removal of solvation significantly reduces the rate of the rotameric motions. We employed 2 H NMR line shape analysis, longitudinal and rotation frame relaxation, and chemical exchange saturation transfer methods and found that the combination of multiple techniques creates a significantly more refined model in comparison with a single technique. Further, we compare the most essential features of the dynamics in RC9 to two different methionine-containing systems, characterized previously. Namely, the M35 of hydrated amyloid-β1-40 in the three-fold symmetric polymorph as well as Fluorenylmethyloxycarbonyl (FMOC)-methionine amino acid with the bulky hydrophobic group. The comparison suggests that the driving force for the enhanced methionine side chain mobility in RC9 is the thermodynamic factor stemming from distributions of rotameric populations, rather than the increase in the rate constant.
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Affiliation(s)
- Liliya Vugmeyster
- Department of Chemistry, University of Colorado Denver, Denver CO USA 80204
| | - Dmitry Ostrovsky
- Department of Mathematics, University of Colorado Denver, Denver CO USA 80204
| | - Aryana Rodgers
- Department of Chemistry, University of Colorado Denver, Denver CO USA 80204
| | - Kirsten Gwin
- Department of Chemistry, University of Colorado Denver, Denver CO USA 80204
| | - Serge L. Smirnov
- Department of Chemistry, Western Washington University, Bellingham, WA 98225
| | - C. James McKnight
- Department of Pharmacology, Physiology and Biophysics, Boston University Chobanian and Avedisian School of Medicine, Boston, MA, 02118
| | - Riqiang Fu
- National High Magnetic Field Laboratory, Tallahassee, FL USA 32310
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4
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Vugmeyster L, Au DF, Frazier B, Qiang W, Ostrovsky D. Rigidifying of the internal dynamics of amyloid-beta fibrils generated in the presence of synaptic plasma vesicles. Phys Chem Chem Phys 2024; 26:5466-5478. [PMID: 38277177 PMCID: PMC10956644 DOI: 10.1039/d3cp04824a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2024]
Abstract
We investigated the changes in internal flexibility of amyloid-β1-40 (Aβ) fibrils grown in the presence of rat synaptic plasma vesicles. The fibrils are produced using a modified seeded growth protocol, in which the Aβ concentration is progressively increased at the expense of the decreased lipid to protein ratio. The morphologies of each generation are carefully assessed at several fibrils' growth time points using transmission electron microscopy. The side-chain dynamics in the fibrils is investigated using deuterium solid-state NMR measurements, with techniques spanning line shapes analysis and several NMR relaxation rates measurements. The dynamics is probed in the site-specific fashion in the hydrophobic C-terminal domain and the disordered N-terminal domain. An overall strong rigidifying effect is observed in comparison with the wild-type fibrils generated in the absence of the membranes. In particular, the overall large-scale fluctuations of the N-terminal domain are significantly reduced, and the activation energies of rotameric inter-conversion in methyl-bearing side-chains of the core (L17, L34, M35, V36), as well as the ring-flipping motions of F19 are increased, indicating a restricted core environment. Membrane-induced flexibility changes in Aβ aggregates can be important for the re-alignment of protein aggregates within the membrane, which in turn would act as a disruption pathway of the bilayers' integrity.
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Affiliation(s)
- Liliya Vugmeyster
- Department of Chemistry, University of Colorado Denver, Denver, CO, USA, 80204.
| | - Dan Fai Au
- Department of Chemistry, University of Colorado Denver, Denver, CO, USA, 80204.
| | - Bailey Frazier
- Department of Chemistry, University of Colorado Denver, Denver, CO, USA, 80204.
| | - Wei Qiang
- Department of Chemistry, Binghamton University, Binghamton, New York, USA, 13902
| | - Dmitry Ostrovsky
- Department of Mathematics, University of Colorado Denver, Denver, CO, USA, 80204
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Vugmeyster L, Rodgers A, Ostrovsky D, James McKnight C, Fu R. Deuteron off-resonance rotating frame relaxation for the characterization of slow motions in rotating and static solid-state proteins. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2023; 352:107493. [PMID: 37271094 PMCID: PMC10330767 DOI: 10.1016/j.jmr.2023.107493] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 05/24/2023] [Accepted: 05/25/2023] [Indexed: 06/06/2023]
Abstract
We demonstrate the feasibility of deuterium solid-state NMR off-resonance rotating frame relaxation measurements for studies of slow motions in biomolecular solids. The pulse sequence, which includes adiabatic pulses for magnetization alignment, is illustrated for static and magic-angle spinning conditions away from rotary resonances. We apply the measurements for three systems with selective deuterium labels at methyl groups: a) a model compound, Fluorenylmethyloxycarbonyl methionine-D3 amino acid, for which the principles of the measurements and corresponding motional modeling based on rotameric interconversions are demonstrated; b) amyloid-β1-40 fibrils labeled at a single alanine methyl group located in the disordered N-terminal domain. This system has been extensively studied in prior work and here serves as a test of the method for complex biological systems. The essential features of the dynamics consist of large-scale rearrangements of the disordered N-terminal domain and the conformational exchange between the free and bound forms of the domain, the latter one due to transient interactions with the structured core of the fibrils. and c) a 15-residue helical peptide which belongs to the predicted α-helical domain near the N-terminus of apolipoprotein B. The peptide is solvated with triolein and incorporates a selectively labeled leucine methyl groups. The method permits model refinement, indicating rotameric interconversions with a distribution of rate constants.
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Affiliation(s)
- Liliya Vugmeyster
- Department of Chemistry, University of Colorado Denver, Denver, CO 80204, USA.
| | - Aryana Rodgers
- Department of Chemistry, University of Colorado Denver, Denver, CO 80204, USA
| | - Dmitry Ostrovsky
- Department of Mathematics, University of Colorado Denver, Denver, CO 80204, USA
| | - C James McKnight
- Department of Pharmacology, Physiology and Biophysics, Boston University Chobanian and Avedisian School of Medicine, Boston, MA 02118, United States
| | - Riqiang Fu
- National High Field Magnetic Laboratory, Tallahassee, FL 32310, USA
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6
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Akbey Ü. Site-specific protein backbone deuterium 2H α quadrupolar patterns by proton-detected quadruple-resonance 3D 2H αc αNH MAS NMR spectroscopy. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2023; 125:101861. [PMID: 36989552 DOI: 10.1016/j.ssnmr.2023.101861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 02/23/2023] [Accepted: 03/06/2023] [Indexed: 06/11/2023]
Abstract
A novel deuterium-excited and proton-detected quadruple-resonance three-dimensional (3D) 2HαcαNH MAS nuclear magnetic resonance (NMR) method is presented to obtain site-specific 2Hα deuterium quadrupolar couplings from protein backbone, as an extension to the 2D version of the experiment reported earlier. Proton-detection results in high sensitivity compared to the heteronuclei detection methods. Utilizing four independent radiofrequency (RF) channels (quadruple-resonance), we managed to excite the 2Hα, then transfer deuterium polarization to its attached Cα, followed by polarization transfers to the neighboring backbone nitrogen and then to the amide proton for detection. This experiment results in an easy to interpret HSQC-like 2D 1H-15N fingerprint NMR spectrum, which contains site-specific deuterium quadrupolar patterns in the indirect third dimension. Provided that four-channel NMR probe technology is available, the setup of the 2HαcαNH experiment is relatively straightforward, by using low power deuterium excitation and polarization transfer schemes we have been developing. To our knowledge, this is the first demonstration of a quadruple-resonance MAS NMR experiment to link 2Hα quadrupolar couplings to proton-detection, extending our previous triple-resonance demonstrations. Distortion-free excitation and polarization transfer of ∼160-170 kHz 2Hα quadrupolar coupling were presented by using a deuterium RF strength of ∼20 kHz. From these 2Hα patterns, an average backbone order parameter of S = 0.92 was determined on a deuterated SH3 sample, with an average η = 0.22. These indicate that SH3 backbone represents sizable dynamics in the microsecond timescale where the 2Hα lineshape is sensitive. Moreover, site-specific 2Hα T1 relaxation times were obtained for a proof of concept. This 3D 2HαcαNH NMR experiment has the potential to determine structure and dynamics of perdeuterated proteins by utilizing deuterium as a novel reporter.
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Affiliation(s)
- Ümit Akbey
- Department of Structural Biology, School of Medicine, University of Pittsburgh, Biomedical Science Tower 3, 3501 Fifth Avenue, Pittsburgh, 15261, United States.
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7
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Borcik C, Eason IR, Vanderloop B, Wylie BJ. 2H, 13C-Cholesterol for Dynamics and Structural Studies of Biological Membranes. ACS OMEGA 2022; 7:17151-17160. [PMID: 35647452 PMCID: PMC9134247 DOI: 10.1021/acsomega.2c00796] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 04/08/2022] [Indexed: 05/19/2023]
Abstract
We present a cost-effective means of 2H and 13C enrichment of cholesterol. This method exploits the metabolism of 2H,13C-acetate into acetyl-CoA, the first substrate in the mevalonate pathway. We show that growing the cholesterol producing strain RH6827 of Saccharomyces cerevisiae in 2H,13C-acetate-enriched minimal media produces a skip-labeled pattern of deuteration. We characterize this cholesterol labeling pattern by mass spectrometry and solid-state nuclear magnetic resonance spectroscopy. It is confirmed that most 2H nuclei retain their original 2H-13C bonds from acetate throughout the biosynthetic pathway. We then quantify the changes in 13C chemical shifts brought by deuteration and the impact upon 13C-13C spin diffusion. Finally, using adiabatic rotor echo short pulse irradiation cross-polarization (RESPIRATIONCP), we acquire the 2H-13C correlation spectra to site specifically quantify cholesterol dynamics in two model membranes as a function of temperature. These measurements show that cholesterol acyl chains at physiological temperatures in mixtures of 1-palmitoyl-2-oleoylphosphatidylcholine (POPC), sphingomyelin, and cholesterol are more dynamic than cholesterol in POPC. However, this overall change in motion is not uniform across the cholesterol molecule. This result establishes that this cholesterol labeling pattern will have great utility in reporting on cholesterol dynamics and orientation in a variety of environments and with different membrane bilayer components, as well as monitoring the mevalonate pathway product interactions within the bilayer. Finally, the flexibility and universality of acetate labeling will allow this technique to be widely applied to a large range of lipids and other natural products.
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8
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Vugmeyster L, Ostrovsky D, Greenwood A, Fu R. Deuteron rotating frame relaxation for the detection of slow motions in rotating solids. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2022; 337:107171. [PMID: 35219160 PMCID: PMC8994516 DOI: 10.1016/j.jmr.2022.107171] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 02/15/2022] [Accepted: 02/16/2022] [Indexed: 06/06/2023]
Abstract
We demonstrate experimental and computational approaches for measuring 2H rotating frame NMR relaxation for solid samples under magic angle spinning (MAS) conditions. The relaxation properties of the deuterium spin-1 system are dominated by the reorientation of the anisotropic quadrupolar tensors, with the effective quadrupolar coupling constant around 55 kHz for methyl groups. The technique is demonstrated using the model compound dimethyl-sulfone at MAS rates of 10 and 60 kHz as well as for an amyloid fibril sample comprising an amyloid-β (1-40) protein with a selective methyl group labeled in the disordered domain of the fibrils, at an MAS rate of 8 kHz. For both systems, the motional parameters fall well within the ranges determined by other techniques, thus validating its feasibility. Experimental and computational factors such as i) the probe's radio frequency inhomogeneity profiles, ii) rotary resonances at conditions for which the spin-lock field strength matches the half- or full-integer of the MAS rate, iii) the choice of MAS rates and spin-lock field strengths, and iv) simulations that account for the interconversion of multiple coherences for the spin-1 system under MAS and deviations from the analytical Redfield treatment are thoroughly considered.
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Affiliation(s)
- Liliya Vugmeyster
- Department of Chemistry, University of Colorado Denver, Denver, CO 80204, USA.
| | - Dmitry Ostrovsky
- Department of Mathematics, University of Colorado Denver, Denver, CO 80204, USA
| | - Alexander Greenwood
- Department of Chemistry, University of Cincinnati, Cincinnati, OH 45221-0172, USA
| | - Riqiang Fu
- National High Field Magnetic Laboratory, Tallahassee, FL 32310, USA
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9
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Akbey Ü. Site-specific protein methyl deuterium quadrupolar patterns by proton-detected 3D 2H- 13C- 1H MAS NMR spectroscopy. JOURNAL OF BIOMOLECULAR NMR 2022; 76:23-28. [PMID: 34997409 DOI: 10.1007/s10858-021-00388-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Accepted: 11/30/2021] [Indexed: 06/14/2023]
Abstract
Determination of protein structure and dynamics is key to understand the mechanism of protein action. Perdeuterated proteins have been used to obtain high resolution/sensitivty NMR experiments via proton-detection. These methods utilizes 1H, 13C and 15N nuclei for chemical shift dispersion or relaxation probes, despite the existing abundant deuterons. However, a high-sensitivity NMR method to utilize deuterons and e.g. determine site-specific deuterium quadrupolar pattern information has been lacking due to technical difficulties associated with deuterium's large quadrupolar couplings. Here, we present a novel deuterium-excited and proton-detected three-dimensional 2H-13C-1H MAS NMR experiment to utilize deuterons and to obtain site-specific methyl 2H quadrupolar patterns on detuterated proteins for the first time. A high-resolution fingerprint 1H-15N HSQC-spectrum is correlated with the anisotropic deuterium quadrupolar tensor in the third dimension. Results from a model perdeuterated protein has been shown.
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Affiliation(s)
- Ümit Akbey
- Radboud University, Magnetic Resonance Research Center, Institute for Molecules and Materials, Nijmegen, The Netherlands.
- Department of Structural Biology, University of Pittsburgh School of Medicine, 3501 Fifth Ave., Pittsburgh, PA, USA.
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Ahlawat S, Mote KR, Lakomek NA, Agarwal V. Solid-State NMR: Methods for Biological Solids. Chem Rev 2022; 122:9643-9737. [PMID: 35238547 DOI: 10.1021/acs.chemrev.1c00852] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
In the last two decades, solid-state nuclear magnetic resonance (ssNMR) spectroscopy has transformed from a spectroscopic technique investigating small molecules and industrial polymers to a potent tool decrypting structure and underlying dynamics of complex biological systems, such as membrane proteins, fibrils, and assemblies, in near-physiological environments and temperatures. This transformation can be ascribed to improvements in hardware design, sample preparation, pulsed methods, isotope labeling strategies, resolution, and sensitivity. The fundamental engagement between nuclear spins and radio-frequency pulses in the presence of a strong static magnetic field is identical between solution and ssNMR, but the experimental procedures vastly differ because of the absence of molecular tumbling in solids. This review discusses routinely employed state-of-the-art static and MAS pulsed NMR methods relevant for biological samples with rotational correlation times exceeding 100's of nanoseconds. Recent developments in signal filtering approaches, proton methodologies, and multiple acquisition techniques to boost sensitivity and speed up data acquisition at fast MAS are also discussed. Several examples of protein structures (globular, membrane, fibrils, and assemblies) solved with ssNMR spectroscopy have been considered. We also discuss integrated approaches to structurally characterize challenging biological systems and some newly emanating subdisciplines in ssNMR spectroscopy.
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Affiliation(s)
- Sahil Ahlawat
- Tata Institute of Fundamental Research Hyderabad, Survey No. 36/P Gopanpally, Serilingampally, Ranga Reddy District, Hyderabad 500046, Telangana, India
| | - Kaustubh R Mote
- Tata Institute of Fundamental Research Hyderabad, Survey No. 36/P Gopanpally, Serilingampally, Ranga Reddy District, Hyderabad 500046, Telangana, India
| | - Nils-Alexander Lakomek
- University of Düsseldorf, Institute for Physical Biology, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Vipin Agarwal
- Tata Institute of Fundamental Research Hyderabad, Survey No. 36/P Gopanpally, Serilingampally, Ranga Reddy District, Hyderabad 500046, Telangana, India
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Reif B. Deuteration for High-Resolution Detection of Protons in Protein Magic Angle Spinning (MAS) Solid-State NMR. Chem Rev 2021; 122:10019-10035. [PMID: 34870415 DOI: 10.1021/acs.chemrev.1c00681] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Proton detection developed in the last 20 years as the method of choice to study biomolecules in the solid state. In perdeuterated proteins, proton dipolar interactions are strongly attenuated, which allows yielding of high-resolution proton spectra. Perdeuteration and backsubstitution of exchangeable protons is essential if samples are rotated with MAS rotation frequencies below 60 kHz. Protonated samples can be investigated directly without spin dilution using proton detection methods in case the MAS frequency exceeds 110 kHz. This review summarizes labeling strategies and the spectroscopic methods to perform experiments that yield assignments, quantitative information on structure, and dynamics using perdeuterated samples. Techniques for solvent suppression, H/D exchange, and deuterium spectroscopy are discussed. Finally, experimental and theoretical results that allow estimation of the sensitivity of proton detected experiments as a function of the MAS frequency and the external B0 field in a perdeuterated environment are compiled.
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Affiliation(s)
- Bernd Reif
- Bayerisches NMR Zentrum (BNMRZ) at the Department of Chemistry, Technische Universität München (TUM), Lichtenbergstr. 4, 85747 Garching, Germany.,Helmholtz-Zentrum München (HMGU), Deutsches Forschungszentrum für Gesundheit und Umwelt, Institute of Structural Biology (STB), Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
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