1
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Sučec I, Pankratova Y, Parasar M, Hong M. Transmembrane conformation of the envelope protein of an alpha coronavirus, NL63. Protein Sci 2024; 33:e4923. [PMID: 38501465 PMCID: PMC10949323 DOI: 10.1002/pro.4923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 01/26/2024] [Accepted: 01/27/2024] [Indexed: 03/20/2024]
Abstract
The envelope (E) proteins of coronaviruses (CoVs) form cation-conducting channels that are associated with the pathogenicity of these viruses. To date, high-resolution structural information about these viroporins is limited to the SARS-CoV E protein. To broaden our structural knowledge of other members of this family of viroporins, we now investigate the conformation of the E protein of the human coronavirus (hCoV), NL63. Using two- and three-dimensional magic-angle-spinning NMR, we have measured 13 C and 15 N chemical shifts of the transmembrane domain of E (ETM), which yielded backbone (ϕ, ψ) torsion angles. We further measured the water accessibility of NL63 ETM at neutral pH versus acidic pH in the presence of Ca2+ ions. These data show that NL63 ETM adopts a regular α-helical conformation that is unaffected by pH and the N-terminal ectodomain. Interestingly, the water accessibility of NL63 ETM increases only modestly at acidic pH in the presence of Ca2+ compared to neutral pH, in contrast to SARS ETM, which becomes much more hydrated at acidic pH. This difference suggests a structural basis for the weaker channel conductance of α-CoV compared to β-CoV E proteins. The weaker E channel activity may in turn contribute to the reduced virulence of hCoV-NL63 compared to SARS-CoV viruses.
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Affiliation(s)
- Iva Sučec
- Department of ChemistryMassachusetts Institute of TechnologyCambridgeMassachusettsUSA
| | - Yanina Pankratova
- Department of ChemistryMassachusetts Institute of TechnologyCambridgeMassachusettsUSA
| | - Mriganka Parasar
- Department of ChemistryMassachusetts Institute of TechnologyCambridgeMassachusettsUSA
| | - Mei Hong
- Department of ChemistryMassachusetts Institute of TechnologyCambridgeMassachusettsUSA
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2
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Mammeri NE, Dregni AJ, Duan P, Hong M. Structures of AT8 and PHF1 phosphomimetic tau: Insights into the posttranslational modification code of tau aggregation. Proc Natl Acad Sci U S A 2024; 121:e2316175121. [PMID: 38408247 DOI: 10.1073/pnas.2316175121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Accepted: 01/29/2024] [Indexed: 02/28/2024] Open
Abstract
The microtubule-associated protein tau aggregates into amyloid fibrils in Alzheimer's disease and other neurodegenerative diseases. In these tauopathies, tau is hyperphosphorylated, suggesting that this posttranslational modification (PTM) may induce tau aggregation. Tau is also phosphorylated in normal developing brains. To investigate how tau phosphorylation induces amyloid fibrils, here we report the atomic structures of two phosphomimetic full-length tau fibrils assembled without anionic cofactors. We mutated key Ser and Thr residues to Glu in two regions of the protein. One construct contains three Glu mutations at the epitope of the anti-phospho-tau antibody AT8 (AT8-3E tau), whereas the other construct contains four Glu mutations at the epitope of the antibody PHF1 (PHF1-4E tau). Solid-state NMR data show that both phosphomimetic tau mutants form homogeneous fibrils with a single set of chemical shifts. The AT8-3E tau rigid core extends from the R3 repeat to the C terminus, whereas the PHF1-4E tau rigid core spans R2, R3, and R4 repeats. Cryoelectron microscopy data show that AT8-3E tau forms a triangular multi-layered core, whereas PHF1-4E tau forms a triple-stranded core. Interestingly, a construct combining all seven Glu mutations exhibits the same conformation as PHF1-4E tau. Scalar-coupled NMR data additionally reveal the dynamics and shape of the fuzzy coat surrounding the rigid cores. These results demonstrate that specific PTMs induce structurally specific tau aggregates, and the phosphorylation code of tau contains redundancy.
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Affiliation(s)
- Nadia El Mammeri
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Aurelio J Dregni
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Pu Duan
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - Mei Hong
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139
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3
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Nimerovsky E, Varkey AC, Kim M, Becker S, Andreas LB. Simplified Preservation of Equivalent Pathways Spectroscopy. JACS Au 2023; 3:2763-2771. [PMID: 37885577 PMCID: PMC10598565 DOI: 10.1021/jacsau.3c00312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 09/27/2023] [Accepted: 09/27/2023] [Indexed: 10/28/2023]
Abstract
Inspired by the recently proposed transverse mixing optimal control pulses (TROP) approach for improving signal in multidimensional magic-angle spinning (MAS) NMR experiments, we present simplified preservation of equivalent pathways spectroscopy (SPEPS). It transfers both transverse components of magnetization that occur during indirect evolutions, theoretically enabling a √2 improvement in sensitivity for each such dimension. We compare SPEPS transfer with TROP and cross-polarization (CP) using membrane protein and fibril samples at MAS of 55 and 100 kHz. In three-dimensional (3D) (H)CANH spectra, SPEPS outperformed TROP and CP by factors of on average 1.16 and 1.69, respectively, for the membrane protein, but only a marginal improvement of 1.09 was observed for the fibril. These differences are discussed, making note of the longer transfer time used for CP, 14 ms, as compared with 2.9 and 3.6 ms for SPEPS and TROP, respectively. Using SPEPS for two transfers in the 3D (H)CANCO experiment resulted in an even larger benefit in signal intensity, with an average improvement of 1.82 as compared with CP. This results in multifold time savings, in particular considering the weaker peaks that are observed to benefit the most from SPEPS.
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Affiliation(s)
- Evgeny Nimerovsky
- Department of NMR based Structural
Biology, Max Planck Institute for Multidisciplinary
Sciences, Am Fassberg 11, Göttingen 37077, Germany
| | - Abel Cherian Varkey
- Department of NMR based Structural
Biology, Max Planck Institute for Multidisciplinary
Sciences, Am Fassberg 11, Göttingen 37077, Germany
| | - Myeongkyu Kim
- Department of NMR based Structural
Biology, Max Planck Institute for Multidisciplinary
Sciences, Am Fassberg 11, Göttingen 37077, Germany
| | - Stefan Becker
- Department of NMR based Structural
Biology, Max Planck Institute for Multidisciplinary
Sciences, Am Fassberg 11, Göttingen 37077, Germany
| | - Loren B. Andreas
- Department of NMR based Structural
Biology, Max Planck Institute for Multidisciplinary
Sciences, Am Fassberg 11, Göttingen 37077, Germany
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4
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Biedenbänder T, Bensons ER, Corzilius B. Serial Polarization Transfer by Combination of Cross-Relaxation and Rotational Resonance for Sensitivity-Enhanced Solid-State NMR. Chemphyschem 2023; 24:e202300206. [PMID: 37306393 DOI: 10.1002/cphc.202300206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 06/04/2023] [Accepted: 06/12/2023] [Indexed: 06/13/2023]
Abstract
Methods which induce site-specificity and sensitivity enhancement in solid-state magic-angle spinning NMR spectroscopy become more important for structural biology due to the increasing size of molecules under investigation. Recently, several strategies have been developed to increase site specificity and thus reduce signal overlap. Under dynamic nuclear polarization (DNP) for NMR signal enhancement, it is possible to use cross-relaxation transfer induced by select dynamic groups within the molecules which is exploited by SCREAM-DNP (Specific Cross Relaxation Enhancement by Active Motions under DNP). Here, we present an approach where we additionally reintroduce the homonuclear dipolar coupling with rotational resonance (R2 ) during SCREAM-DNP to further boost the selectivity of the experiment. Detailed analysis of the polarization buildup dynamics of 13 C-methyl polarization source and 13 C-carbonyl target in 2-13 C-ethyl 1-13 C-acetate provides information about the sought-after and spurious transfer pathways. We show that dipolar-recoupled transfer rates greatly exceed the DNP buildup dynamics in our model system, indicating that significantly larger distances can be selectively and efficiently hyperpolarized.
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Affiliation(s)
- Thomas Biedenbänder
- Institute of Chemistry, University of Rostock, Albert-Einstein-Str. 27, 18059, Rostock, Germany
- Department Life, Light & Matter, University of Rostock, Albert-Einstein-Str. 25, 18059, Rostock, Germany
| | - Edvards R Bensons
- Institute of Chemistry, University of Rostock, Albert-Einstein-Str. 27, 18059, Rostock, Germany
- Department Life, Light & Matter, University of Rostock, Albert-Einstein-Str. 25, 18059, Rostock, Germany
| | - Björn Corzilius
- Institute of Chemistry, University of Rostock, Albert-Einstein-Str. 27, 18059, Rostock, Germany
- Department Life, Light & Matter, University of Rostock, Albert-Einstein-Str. 25, 18059, Rostock, Germany
- Leibniz Institute for Catalysis, Albert-Einstein-Str. 29, 18059, Rostock, Germany
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5
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Wong A. A roadmap to high-resolution standard microcoil MAS NMR spectroscopy for metabolomics. NMR Biomed 2023; 36:e4683. [PMID: 34970795 DOI: 10.1002/nbm.4683] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 12/06/2021] [Accepted: 12/21/2021] [Indexed: 06/14/2023]
Abstract
Current microcoil probe technology has emerged as a significant advancement in NMR applications to biofluids research. It has continued to excel as a hyphenated tool with other prominent microdevices, opening many new possibilities in multiple omics fields. However, this does not hold for biological samples such as intact tissue or organisms, due to the considerable challenges of incorporating the microcoil in a magic-angle spinning (MAS) probe without relinquishing the high-resolution spectral data. Not until 2012 did a microcoil MAS probe show promise in profiling the metabolome in a submilligram tissue biopsy with spectral resolution on par with conventional high-resolution MAS (HR-MAS) NMR. This result subsequently triggered a great interest in the possibility of NMR analysis with microgram tissues and striving toward the probe development of "high-resolution" capable microcoil MAS NMR spectroscopy. This review gives an overview of the issues and challenges in the probe development and summarizes the advancements toward metabolomics.
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Affiliation(s)
- Alan Wong
- NIMBE, CEA, CNRS, Université Paris-Saclay, CEA Saclay, Gif-sur-Yvette, France
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6
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Bahri S, Silvers R, Michael B, Jaudzems K, Lalli D, Casano G, Ouari O, Lesage A, Pintacuda G, Linse S, Griffin RG. 1H detection and dynamic nuclear polarization-enhanced NMR of Aβ 1-42 fibrils. Proc Natl Acad Sci U S A 2022; 119:e2114413119. [PMID: 34969859 DOI: 10.1073/pnas.2114413119] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/03/2021] [Indexed: 12/25/2022] Open
Abstract
Amyloid-β (Aβ) is the subject of intense scrutiny because of its close association with Alzheimer’s disease (AD), which currently afflicts about 50 million people worldwide. The results reported in this manuscript focus on the new possibilities provided by ultrafast magic-angle spinning (MAS) 1H detection and fast-MAS dynamic nuclear polarization (DNP), which have ushered in a new era for NMR-based structural biology, but whose potential has not yet been fully exploited for the structural investigation of complex amyloid assemblies. This work demonstrates the expeditious structural analysis of amyloid fibrils, without requiring preparation of large sample amounts, and sets the stage for future studies of unlabeled AD peptides derived from tissue samples available in limited quantities. Several publications describing high-resolution structures of amyloid-β (Aβ) and other fibrils have demonstrated that magic-angle spinning (MAS) NMR spectroscopy is an ideal tool for studying amyloids at atomic resolution. Nonetheless, MAS NMR suffers from low sensitivity, requiring relatively large amounts of samples and extensive signal acquisition periods, which in turn limits the questions that can be addressed by atomic-level spectroscopic studies. Here, we show that these drawbacks are removed by utilizing two relatively recent additions to the repertoire of MAS NMR experiments—namely, 1H detection and dynamic nuclear polarization (DNP). We show resolved and sensitive two-dimensional (2D) and three-dimensional (3D) correlations obtained on 13C,15N-enriched, and fully protonated samples of M0Aβ1-42 fibrils by high-field 1H-detected NMR at 23.4 T and 18.8 T, and 13C-detected DNP MAS NMR at 18.8 T. These spectra enable nearly complete resonance assignment of the core of M0Aβ1-42 (K16-A42) using submilligram sample quantities, as well as the detection of numerous unambiguous internuclear proximities defining both the structure of the core and the arrangement of the different monomers. An estimate of the sensitivity of the two approaches indicates that the DNP experiments are currently ∼6.5 times more sensitive than 1H detection. These results suggest that 1H detection and DNP may be the spectroscopic approaches of choice for future studies of Aβ and other amyloid systems.
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7
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Goldbourt A. Distance measurements to quadrupolar nuclei: Evolution of the rotational echo double resonance technique. Magn Reson Chem 2021; 59:908-919. [PMID: 33729630 DOI: 10.1002/mrc.5150] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 03/09/2021] [Accepted: 03/10/2021] [Indexed: 06/12/2023]
Abstract
Molecular structure determination is the basis for understanding chemical processes and the property of materials. The direct dependence of the magnetic dipolar interaction on the distance makes solid-state nuclear magnetic resonance (NMR) an excellent tool to study molecular structure when X-ray crystallography fails to provide atomic-resolution data. Although techniques to measure distances between pairs of isolated nuclear spin-1/2 pairs are routine and easy to implement using the rotational echo double resonance (REDOR) experiment (Gullion & Schaefer, 1989), the existence of a nucleus with a spin > 1/2, appearing in approximately 75% of the elements in the periodic table, poses a challenge due to difficulties stemming from the large nuclear quadrupolar coupling constant (QCC). This mini-review presents the existing solid-state magic-angle spinning NMR techniques aimed toward the efficient and accurate determination of internuclear distances between a spin-1/2 and a "quadrupolar" nucleus having a spin larger than one half. Analytical expressions are provided for the various recoupling curves stemming from different techniques, and a coherent nomenclature for these various techniques is suggested. Treatment of some special cases such as multiple spin effects and spins with close Larmor frequencies is also discussed. The most advanced methods can recouple spins with quadrupolar frequencies up to tens of megahertz and beyond, expanding the distance measurement capabilities of solid-state NMR to an increasingly growing number of applications and nuclear spin systems.
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Affiliation(s)
- Amir Goldbourt
- School of Chemistry, Tel Aviv University, Tel Aviv, Israel
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8
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Nimerovsky E, Movellan KT, Zhang XC, Forster MC, Najbauer E, Xue K, Dervişoǧlu R, Giller K, Griesinger C, Becker S, Andreas LB. Proton Detected Solid-State NMR of Membrane Proteins at 28 Tesla (1.2 GHz) and 100 kHz Magic-Angle Spinning. Biomolecules 2021; 11:752. [PMID: 34069858 PMCID: PMC8157399 DOI: 10.3390/biom11050752] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 05/09/2021] [Accepted: 05/11/2021] [Indexed: 12/25/2022] Open
Abstract
The available magnetic field strength for high resolution NMR in persistent superconducting magnets has recently improved from 23.5 to 28 Tesla, increasing the proton resonance frequency from 1 to 1.2 GHz. For magic-angle spinning (MAS) NMR, this is expected to improve resolution, provided the sample preparation results in homogeneous broadening. We compare two-dimensional (2D) proton detected MAS NMR spectra of four membrane proteins at 950 and 1200 MHz. We find a consistent improvement in resolution that scales superlinearly with the increase in magnetic field for three of the four examples. In 3D and 4D spectra, which are now routinely acquired, this improvement indicates the ability to resolve at least 2 and 2.5 times as many signals, respectively.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Loren B. Andreas
- Department for NMR-Based Structural Biology, Max-Planck-Institute for Biophysical Chemistry, 37077 Göttingen, Germany; (E.N.); (K.T.M.); (X.C.Z.); (M.C.F.); (E.N.); (K.X.); (R.D.); (K.G.); (C.G.); (S.B.)
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9
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Porat G, Lusky OS, Dayan N, Goldbourt A. Nonuniformly sampled exclusively- 13 C/ 15 N 4D solid-state NMR experiments: Assignment and characterization of IKe phage capsid. Magn Reson Chem 2021; 59:237-246. [PMID: 32603513 DOI: 10.1002/mrc.5072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 06/11/2020] [Accepted: 06/27/2020] [Indexed: 06/11/2023]
Abstract
An important step in the process of protein research by NMR is the assignment of chemical shifts. In the coat protein of IKe bacteriophage, there are 53 residues making up a long helix resulting in relatively high spectral ambiguity. Assignment thus requires the collection of a set of three-dimensional (3D) experiments and the preparation of sparsely labeled samples. Increasing the dimensionality can facilitate fast and reliable assignment of IKe and of larger proteins. Recent progress in nonuniform sampling techniques made the application of multidimensional NMR solid-state experiments beyond 3D more practical. 4D 1 H-detected experiments have been demonstrated in high-fields and at spinning speeds of 60 kHz and higher but are not practical at spinning speeds of 10-20 kHz for fully protonated proteins. Here, we demonstrate the applicability of a nonuniformly sampled 4D 13 C/15 N-only correlation experiment performed at a moderate field of 14.1 T, which can incorporate sufficiently long acquisition periods in all dimensions. We show how a single CANCOCX experiment, supported by several 2D carbon-based correlation experiments, is utilized for the assignment of heteronuclei in the coat protein of the IKe bacteriophage. One sparsely labeled sample was used to validate sidechain assignment of several hydrophobic-residue sidechains. A comparison to solution NMR studies of isolated IKe coat proteins embedded in micelles points to key residues involved in structural rearrangement of the capsid upon assembly of the virus. The benefits of 4D to a quicker assignment are discussed, and the method may prove useful for studying proteins at relatively low fields.
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Affiliation(s)
- Gal Porat
- School of Chemistry, Tel Aviv University, Ramat Aviv, Tel Aviv, 6997801, Israel
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware, 19716, USA
| | - Orr Simon Lusky
- School of Chemistry, Tel Aviv University, Ramat Aviv, Tel Aviv, 6997801, Israel
| | - Nir Dayan
- School of Chemistry, Tel Aviv University, Ramat Aviv, Tel Aviv, 6997801, Israel
- Schulich Faculty of Chemistry, Technion-Institute of Technology, Haifa, Israel
| | - Amir Goldbourt
- School of Chemistry, Tel Aviv University, Ramat Aviv, Tel Aviv, 6997801, Israel
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10
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Wu G, Terskikh V, Wong A. Perspectives of fast magic-angle spinning 87 Rb NMR of organic solids at high magnetic fields. Magn Reson Chem 2021; 59:162-171. [PMID: 32893369 DOI: 10.1002/mrc.5097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 08/31/2020] [Accepted: 09/02/2020] [Indexed: 06/11/2023]
Abstract
We report solid-state 87 Rb NMR spectra from two Rb-ionophore complexes obtained with fast magic-angle spinning (MAS) (up to 60 kHz) at 21.1 T. These Rb-ionophore complexes containing macrocycles such as benzo-15-crown-5 and cryptand [2.2.2] are typical of organic Rb salts that exhibit very large 87 Rb quadrupole coupling constants (close to 20 MHz). We have also obtained static 87 Rb NMR spectra for these two compounds and determined both 87 Rb quadrupole coupling and chemical shift tensors. The experimental 87 Rb NMR tensor parameters are compared with those obtained by quantum chemical computations. Our results demonstrate that the combination of fast MAS (60 kHz or higher) and a high magnetic field (21.1 T or higher) is sufficient to produce high-quality solid-state 87 Rb NMR spectra for organic Rb solids at the natural abundance level. We anticipate that, with additional 87 Rb isotope enrichment (up to 99%), the sensitivity of solid-state 87 Rb NMR will be 400 times higher than 39 K NMR, which makes the former an attractive surrogate probe for studying K+ ion binding in biological systems.
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Affiliation(s)
- Gang Wu
- Department of Chemistry, Queen's University, Kingston, ON, Canada
| | - Victor Terskikh
- Department of Chemistry, Queen's University, Kingston, ON, Canada
- Department of Chemistry, University of Ottawa, Ottawa, ON, Canada
| | - Alan Wong
- Department of Chemistry, Queen's University, Kingston, ON, Canada
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11
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Messinger RJ, Vu Huynh T, Bouchet R, Sarou-Kanian V, Deschamps M. Magic-angle-spinning-induced local ordering in polymer electrolytes and its effects on solid-state diffusion and relaxation NMR measurements. Magn Reson Chem 2020; 58:1118-1129. [PMID: 32324938 DOI: 10.1002/mrc.5033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 04/15/2020] [Accepted: 04/17/2020] [Indexed: 06/11/2023]
Abstract
Magic-angle-spinning (MAS) enhances sensitivity and resolution in solid-state nuclear magnetic resonance (NMR) measurements. MAS is obtained by aerodynamic levitation and drive of a rotor, which results in large centrifugal forces that may affect the physical state of soft materials, such as polymers, and subsequent solid-state NMR measurements. Here, we investigate the effects of MAS on the solid-state NMR measurements of a polymer electrolyte for lithium-ion battery applications, poly(ethylene oxide) (PEO) doped with the lithium salt LiTFSI. We show that MAS induces local chain ordering, which manifests itself as characteristic lineshapes with doublet-like splittings in subsequent solid-state 1 H, 7 Li, and 19 F static NMR spectra characterizing the PEO chains and solvated ions. MAS results in distributions of stresses and hence local chain orientations within the rotor, yielding distributions in the local magnetic susceptibility tensor that give rise to the observed NMR anisotropy and lineshapes. The effects of MAS were investigated on solid-state 7 Li and 19 F pulsed-field-gradient (PFG) diffusion and 7 Li longitudinal relaxation NMR measurements. Activation energies for ion diffusion were affected modestly by MAS. 7 Li longitudinal relaxation rates, which are sensitive to lithium-ion dynamics in the nanosecond regime, were essentially unchanged by MAS. We recommend that NMR researchers studying soft polymeric materials use only the spin rates necessary to achieve the desired enhancements in sensitivity and resolution, as well as acquire static NMR spectra after MAS experiments to reveal any signs of stress-induced local ordering.
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Affiliation(s)
- Robert J Messinger
- Department of Chemical Engineering, The City College of New York, CUNY, New York, NY, 10031, USA
| | - Tan Vu Huynh
- CEMHTI, CNRS UPR 3079, Université d'Orléans, Orléans, F-45071, France
- RS2E, Réseau sur le Stockage Électrochimique de l'Énergie, FR CNRS 3459, F-80039, Amiens, France
| | - Renaud Bouchet
- LEPMI, CNRS UMR 5279, Université Grenoble Alpes, Grenoble, F-38000, France
| | - Vincent Sarou-Kanian
- CEMHTI, CNRS UPR 3079, Université d'Orléans, Orléans, F-45071, France
- RS2E, Réseau sur le Stockage Électrochimique de l'Énergie, FR CNRS 3459, F-80039, Amiens, France
| | - Michaël Deschamps
- CEMHTI, CNRS UPR 3079, Université d'Orléans, Orléans, F-45071, France
- RS2E, Réseau sur le Stockage Électrochimique de l'Énergie, FR CNRS 3459, F-80039, Amiens, France
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12
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Schubeis T, Le Marchand T, Daday C, Kopec W, Tekwani Movellan K, Stanek J, Schwarzer TS, Castiglione K, de Groot BL, Pintacuda G, Andreas LB. A β-barrel for oil transport through lipid membranes: Dynamic NMR structures of AlkL. Proc Natl Acad Sci U S A 2020; 117:21014-21. [PMID: 32817429 DOI: 10.1073/pnas.2002598117] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Here we show how AlkL, a minimalistic outer-membrane protein from oil-consuming bacteria, exploits dynamics of extracellular loops to channel substrate across the polysaccharide barrier and into the hydrophobic interior of the outer membrane. This work represents a unique example of a side-by-side atomic-level structure determination by solution NMR in detergents and by solid-state NMR in lipid bilayers, which critically demonstrates the importance of a lipid environment to investigate function. Corroborating our experimental measurements, molecular-dynamics simulations capture substrate transit via lateral openings. The capacity to unravel membrane protein function under near-native conditions, fueled by the latest method developments, opens up a new frontier for their investigation, and provides thereby for improved fundamental insights into biological processes. The protein AlkL is known to increase permeability of the outer membrane of bacteria for hydrophobic molecules, yet the mechanism of transport has not been determined. Differing crystal and NMR structures of homologous proteins resulted in a controversy regarding the degree of structure and the role of long extracellular loops. Here we solve this controversy by determining the de novo NMR structure in near-native lipid bilayers, and by accessing structural dynamics relevant to hydrophobic substrate permeation through molecular-dynamics simulations and by characteristic NMR relaxation parameters. Dynamic lateral exit sites large enough to accommodate substrates such as carvone or octane occur through restructuring of a barrel extension formed by the extracellular loops.
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13
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Affiliation(s)
- Mattias Edén
- Physical Chemistry Division, Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91 Stockholm, Sweden
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14
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Hoffmann J, Ruta J, Shi C, Hendriks K, Chevelkov V, Franks WT, Oschkinat H, Giller K, Becker S, Lange A. Protein resonance assignment by BSH-CP-based 3D solid-state NMR experiments: A practical guide. Magn Reson Chem 2020; 58:445-465. [PMID: 31691361 DOI: 10.1002/mrc.4945] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 07/05/2019] [Accepted: 09/17/2019] [Indexed: 06/10/2023]
Abstract
Solid-state NMR (ssNMR) spectroscopy has evolved into a powerful method to obtain structural information and to study the dynamics of proteins at atomic resolution and under physiological conditions. The method is especially well suited to investigate insoluble and noncrystalline proteins that cannot be investigated easily by X-ray crystallography or solution NMR. To allow for detailed analysis of ssNMR data, the assignment of resonances to the protein atoms is essential. For this purpose, a set of three-dimensional (3D) spectra needs to be acquired. Band-selective homo-nuclear cross-polarization (BSH-CP) is an effective method for magnetization transfer between carbonyl carbon (CO) and alpha carbon (CA) atoms, which is an important transfer step in multidimensional ssNMR experiments. This tutorial describes the detailed procedure for the chemical shift assignment of the backbone atoms of 13 C-15 N-labeled proteins by BSH-CP-based 13 C-detected ssNMR experiments. A set of six 3D experiments is used for unambiguous assignment of the protein backbone as well as certain side-chain resonances. The tutorial especially addresses scientists with little experience in the field of ssNMR and provides all the necessary information for protein assignment in an efficient, time-saving approach.
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Affiliation(s)
- Jutta Hoffmann
- Department of Molecular Biophysics, Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
| | - Julia Ruta
- Department of Molecular Biophysics, Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
| | - Chaowei Shi
- Department of Molecular Biophysics, Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
| | - Kitty Hendriks
- Department of Molecular Biophysics, Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
| | - Veniamin Chevelkov
- Department of Molecular Biophysics, Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
| | - W Trent Franks
- Department of NMR-supported Structural Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
| | - Hartmut Oschkinat
- Department of NMR-supported Structural Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
| | - Karin Giller
- Department of NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Stefan Becker
- Department of NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Adam Lange
- Department of Molecular Biophysics, Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany
- Institut für Biologie, Humboldt-Universität zu Berlin, Berlin, Germany
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15
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Lucas-Torres C, Wong A. Current Developments in µMAS NMR Analysis for Metabolomics. Metabolites 2019; 9:metabo9020029. [PMID: 30736341 PMCID: PMC6410107 DOI: 10.3390/metabo9020029] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Revised: 02/02/2019] [Accepted: 02/02/2019] [Indexed: 12/30/2022] Open
Abstract
Analysis of microscopic specimens has emerged as a useful analytical application in metabolomics because of its capacity for characterizing a highly homogenous sample with a specific interest. The undeviating analysis helps to unfold the hidden activities in a bulk specimen and contributes to the understanding of the fundamental metabolisms in life. In NMR spectroscopy, micro(µ)-probe technology is well-established and -adopted to the microscopic level of biofluids. However, this is quite the contrary with specimens such as tissue, cell and organism. This is due to the substantial difficulty of developing a sufficient µ-size magic-angle spinning (MAS) probe for sub-milligram specimens with the capability of high-quality data acquisition. It was not until 2012; a µMAS probe had emerged and shown promises to µg analysis; since, a continuous advancement has been made striving for the possibility of µMAS to be an effective NMR spectroscopic analysis. Herein, the mini-review highlights the progress of µMAS development—from an impossible scenario to an attainable solution—and describes a few demonstrative metabolic profiling studies. The review will also discuss the current challenges in µMAS NMR analysis and its potential to metabolomics.
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Affiliation(s)
| | - Alan Wong
- NIMBE, CEA, CNRS, Université Paris-Saclay, CEA Saclay 91191 Gif-sur-Yvette, France.
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16
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Najbauer EE, Movellan KT, Schubeis T, Schwarzer T, Castiglione K, Giller K, Pintacuda G, Becker S, Andreas LB. Probing Membrane Protein Insertion into Lipid Bilayers by Solid-State NMR. Chemphyschem 2018; 20:302-310. [PMID: 30452110 DOI: 10.1002/cphc.201800793] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 11/08/2018] [Indexed: 11/09/2022]
Abstract
Determination of the environment surrounding a protein is often key to understanding its function and can also be used to infer the structural properties of the protein. By using proton-detected solid-state NMR, we show that reduced spin diffusion within the protein under conditions of fast magic-angle spinning, high magnetic field, and sample deuteration allows the efficient measurement of site-specific exposure to mobile water and lipids. We demonstrate this site specificity on two membrane proteins, the human voltage dependent anion channel, and the alkane transporter AlkL from Pseudomonas putida. Transfer from lipids is observed selectively in the membrane spanning region, and an average lipid-protein transfer rate of 6 s-1 was determined for residues protected from exchange. Transfer within the protein, as tracked in the 15 N-1 H 2D plane, was estimated from initial rates and found to be in a similar range of about 8 to 15 s-1 for several resolved residues, explaining the site specificity.
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Affiliation(s)
- Eszter E Najbauer
- Department of NMR based Structural Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077, Göttingen, Germany
| | - Kumar Tekwani Movellan
- Department of NMR based Structural Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077, Göttingen, Germany
| | - Tobias Schubeis
- Centre de RMN à Très Hauts Champs, Institut des Sciences Analytiques, UMR 5280/CNRS, ENS Lyon, UCB Lyon 1, Université de Lyon, Villeurbanne, France
| | - Tom Schwarzer
- Institute of Biochemical Engineering, Technical University of Munich, Boltzmannstraße 15, D-85748, Garching, Germany
| | - Kathrin Castiglione
- Institute of Bioprocess Engineering, Friedrich-Alexander-Universität Erlangen-Nürnberg, Paul-Gordan-Straße 3, 91052, Erlangen, Germany
| | - Karin Giller
- Department of NMR based Structural Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077, Göttingen, Germany
| | - Guido Pintacuda
- Centre de RMN à Très Hauts Champs, Institut des Sciences Analytiques, UMR 5280/CNRS, ENS Lyon, UCB Lyon 1, Université de Lyon, Villeurbanne, France
| | - Stefan Becker
- Department of NMR based Structural Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077, Göttingen, Germany
| | - Loren B Andreas
- Department of NMR based Structural Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077, Göttingen, Germany
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17
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Poulhazan A, Arnold AA, Warschawski DE, Marcotte I. Unambiguous Ex Situ and in Cell 2D 13C Solid-State NMR Characterization of Starch and Its Constituents. Int J Mol Sci 2018; 19:E3817. [PMID: 30513587 PMCID: PMC6320826 DOI: 10.3390/ijms19123817] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 11/23/2018] [Accepted: 11/28/2018] [Indexed: 11/23/2022] Open
Abstract
Starch is the most abundant energy storage molecule in plants and is an essential part of the human diet. This glucose polymer is composed of amorphous and crystalline domains in different forms (A and B types) with specific physicochemical properties that determine its bioavailability for an organism, as well as its value in the food industry. Using two-dimensional (2D) high resolution solid-state nuclear magnetic resonance (SS-NMR) on 13C-labelled starches that were obtained from Chlamydomonas reinhardtii microalgae, we established a complete and unambiguous assignment for starch and its constituents (amylopectin and amylose) in the two crystalline forms and in the amorphous state. We also assigned so far unreported non-reducing end groups and assessed starch chain length, crystallinity and amylose content. Starch was then characterized in situ, i.e., by 13C solid-state NMR of intact microalgal cells. Our in-cell methodology also enabled the identification of the effect of nitrogen starvation on starch metabolism. This work shows how solid-state NMR can enable the identification of starch structure, chemical modifications and biosynthesis in situ in intact microorganisms, eliminating time consuming and potentially altering purification steps.
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Affiliation(s)
- Alexandre Poulhazan
- Department of Chemistry, Université du Québec à Montréal, Downtown Station, P.O. Box 8888, Montreal, QC H3C 3P8, Canada.
| | - Alexandre A Arnold
- Department of Chemistry, Université du Québec à Montréal, Downtown Station, P.O. Box 8888, Montreal, QC H3C 3P8, Canada.
| | - Dror E Warschawski
- Department of Chemistry, Université du Québec à Montréal, Downtown Station, P.O. Box 8888, Montreal, QC H3C 3P8, Canada.
- Laboratoire de Biologie Physico-Chimique des Protéines Membranaires, UMR 7099, CNRS, Université Paris Diderot and IBPC, 13 rue Pierre et Marie-Curie, 75005 Paris, France.
| | - Isabelle Marcotte
- Department of Chemistry, Université du Québec à Montréal, Downtown Station, P.O. Box 8888, Montreal, QC H3C 3P8, Canada.
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18
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Aharoni T, Goldbourt A. Dynamics and Rigidity of an Intact Filamentous Bacteriophage Virus Probed by Magic Angle Spinning NMR. Chemistry 2018; 24:8737-8741. [PMID: 29660798 DOI: 10.1002/chem.201800532] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 04/11/2018] [Indexed: 12/12/2022]
Abstract
The capsid dynamics of filamentous bacteriophages is related to their function, stability, and interactions with the genome, and can be assessed by measuring the chemical shift anisotropy (CSA) of 15 N amides, which are sensitive to large amplitude motions. In this study, CSA recoupling experiments under magic-angle spinning NMR were used to probe the dynamics of the y21m capsid mutant of fd bacteriophage. Based on fitting the generated CSA lineshapes, residues located in the N-terminus undergo increased motional amplitudes suggesting its global motion, whereas other backbone residues are rigid, and imply a tight hydrophobic packing of the phage.
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Affiliation(s)
- Tom Aharoni
- School of Chemistry, The Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv, 6997801, Israel
| | - Amir Goldbourt
- School of Chemistry, The Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv, 6997801, Israel
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19
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Xiang S, le Paige UB, Horn V, Houben K, Baldus M, van Ingen H. Site-Specific Studies of Nucleosome Interactions by Solid-State NMR Spectroscopy. Angew Chem Int Ed Engl 2018; 57:4571-4575. [PMID: 29465771 PMCID: PMC5947581 DOI: 10.1002/anie.201713158] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 02/08/2018] [Indexed: 01/01/2023]
Abstract
Chromatin function depends on a dense network of interactions between nucleosomes and a wide range of proteins. A detailed description of these protein-nucleosome interactions is required to reach a full molecular understanding of chromatin function in both genetics and epigenetics. Herein, we show that the structure, dynamics, and interactions of nucleosomes can be interrogated in a residue-specific manner by using state-of-the-art solid-state NMR spectroscopy. Using sedimented nucleosomes, high-resolution spectra were obtained for both flexible histone tails and the non-mobile histone core. Through co-sedimentation of a nucleosome-binding peptide, we demonstrate that protein-binding sites on the nucleosome surface can be determined. We believe that this approach holds great promise as it is generally applicable, extendable to include the structure and dynamics of the bound proteins, and scalable to interactions of proteins with higher-order chromatin structures, including isolated and cellular chromatin.
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Affiliation(s)
- ShengQi Xiang
- NMR Spectroscopy Research GroupBijvoet Center for Biomolecular ResearchUtrecht UniversityPadualaan 83584 CHUtrechtThe Netherlands
| | - Ulric B. le Paige
- Macromolecular BiochemistryLeiden Institute of ChemistryLeiden UniversityEinsteinweg 552333 CCLeidenThe Netherlands
- Current address: NMR Spectroscopy Research GroupBijvoet Center for Biomolecular ResearchUtrecht UniversityPadualaan 83584 CHUtrechtThe Netherlands
| | - Velten Horn
- Macromolecular BiochemistryLeiden Institute of ChemistryLeiden UniversityEinsteinweg 552333 CCLeidenThe Netherlands
- Current address: NMR Spectroscopy Research GroupBijvoet Center for Biomolecular ResearchUtrecht UniversityPadualaan 83584 CHUtrechtThe Netherlands
| | - Klaartje Houben
- NMR Spectroscopy Research GroupBijvoet Center for Biomolecular ResearchUtrecht UniversityPadualaan 83584 CHUtrechtThe Netherlands
- Current address: DSM Food SpecialtiesDSM Biotechnology CenterAlexander Flemminglaan 12613 AXDelftThe Netherlands
| | - Marc Baldus
- NMR Spectroscopy Research GroupBijvoet Center for Biomolecular ResearchUtrecht UniversityPadualaan 83584 CHUtrechtThe Netherlands
| | - Hugo van Ingen
- Macromolecular BiochemistryLeiden Institute of ChemistryLeiden UniversityEinsteinweg 552333 CCLeidenThe Netherlands
- Current address: NMR Spectroscopy Research GroupBijvoet Center for Biomolecular ResearchUtrecht UniversityPadualaan 83584 CHUtrechtThe Netherlands
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20
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Loquet A, Tolchard J, Berbon M, Martinez D, Habenstein B. Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy. J Vis Exp 2017:55779. [PMID: 28994783 PMCID: PMC5752270 DOI: 10.3791/55779] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Supramolecular protein assemblies play fundamental roles in biological processes ranging from host-pathogen interaction, viral infection to the propagation of neurodegenerative disorders. Such assemblies consist in multiple protein subunits organized in a non-covalent way to form large macromolecular objects that can execute a variety of cellular functions or cause detrimental consequences. Atomic insights into the assembly mechanisms and the functioning of those macromolecular assemblies remain often scarce since their inherent insolubility and non-crystallinity often drastically reduces the quality of the data obtained from most techniques used in structural biology, such as X-ray crystallography and solution Nuclear Magnetic Resonance (NMR). We here present magic-angle spinning solid-state NMR spectroscopy (SSNMR) as a powerful method to investigate structures of macromolecular assemblies at atomic resolution. SSNMR can reveal atomic details on the assembled complex without size and solubility limitations. The protocol presented here describes the essential steps from the production of 13C/15N isotope-labeled macromolecular protein assemblies to the acquisition of standard SSNMR spectra and their analysis and interpretation. As an example, we show the pipeline of a SSNMR structural analysis of a filamentous protein assembly.
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Affiliation(s)
- Antoine Loquet
- Institute of Chemistry, Biology of Membranes, Nanoobjects, UMR5248 CNRS, Université de Bordeaux;
| | - James Tolchard
- Institute of Chemistry, Biology of Membranes, Nanoobjects, UMR5248 CNRS, Université de Bordeaux
| | - Melanie Berbon
- Institute of Chemistry, Biology of Membranes, Nanoobjects, UMR5248 CNRS, Université de Bordeaux
| | - Denis Martinez
- Institute of Chemistry, Biology of Membranes, Nanoobjects, UMR5248 CNRS, Université de Bordeaux
| | - Birgit Habenstein
- Institute of Chemistry, Biology of Membranes, Nanoobjects, UMR5248 CNRS, Université de Bordeaux;
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21
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Frantsuzov I, Vasa SK, Ernst M, Brown SP, Zorin V, Kentgens APM, Hodgkinson P. Rationalising Heteronuclear Decoupling in Refocussing Applications of Solid-State NMR Spectroscopy. Chemphyschem 2017; 18:394-405. [PMID: 28111874 PMCID: PMC5396389 DOI: 10.1002/cphc.201601003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 11/07/2016] [Indexed: 12/16/2022]
Abstract
Factors affecting the performance of 1 H heteronuclear decoupling sequences for magic-angle spinning (MAS) NMR spectroscopy of organic solids are explored, as observed by time constants for the decay of nuclear magnetisation under a spin-echo (T2' ). By using a common protocol over a wide range of experimental conditions, including very high magnetic fields and very high radio-frequency (RF) nutation rates, decoupling performance is observed to degrade consistently with increasing magnetic field. Inhomogeneity of the RF field is found to have a significant impact on T2' values, with differences of about 20 % observed between probes with different coil geometries. Increasing RF nutation rates dramatically improve robustness with respect to RF offset, but the performance of phase-modulated sequences degrades at the very high nutation rates achievable in microcoils as a result of RF transients. The insights gained provide better understanding of the factors limiting decoupling performance under different conditions, and the high values of T2' observed (which generally exceed previous literature values) provide reference points for experiments involving spin magnetisation refocussing, such as 2D correlation spectra and measuring small spin couplings.
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Affiliation(s)
- Ilya Frantsuzov
- Department of ChemistryDurham UniversitySouth RoadDurhamDH1 3LEUnited Kingdom
| | - Suresh K. Vasa
- Institute for Molecules and MaterialsRadboud UniversityHeyendaalseweg 1356525 EDNijmegenThe Netherlands
| | - Matthias Ernst
- Laboratory of Physical ChemistryETH ZürichVladimir-Prelog-Weg 28093ZürichSwitzerland
| | - Steven P. Brown
- Department of PhysicsUniversity of WarwickCoventryCV4 7ALUnited Kingdom
| | - Vadim Zorin
- Agilent Technologies (UK) Ltd.6 Mead RoadYarntonOxfordshireOX5 1QUUnited Kingdom
- Mestrelab ResearchS.L Feliciano Barrera 9B—Bajo15706Santiago de CompostelaSpain
| | - Arno P. M. Kentgens
- Institute for Molecules and MaterialsRadboud UniversityHeyendaalseweg 1356525 EDNijmegenThe Netherlands
| | - Paul Hodgkinson
- Department of ChemistryDurham UniversitySouth RoadDurhamDH1 3LEUnited Kingdom
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22
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Thomas B, Rombouts J, Oostergetel GT, Gupta KBSS, Buda F, Lammertsma K, Orru R, de Groot HJM. A Hybrid Solid-State NMR and Electron Microscopy Structure-Determination Protocol for Engineering Advanced para-Crystalline Optical Materials. Chemistry 2017; 23:3280-3284. [PMID: 28117921 PMCID: PMC5347911 DOI: 10.1002/chem.201700324] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Indexed: 01/04/2023]
Abstract
Hybrid magic‐angle spinning (MAS) NMR spectroscopy and TEM were demonstrated for de novo structure determination of para‐crystalline materials with a bioinspired fused naphthalene diimide (NDI)–salphen–phenazine prototype light‐harvesting compound. Starting from chiral building blocks with C2 molecular symmetry, the asymmetric unit was determined by MAS NMR spectroscopy, index low‐resolution TEM diffraction data, and resolve reflection conditions, and for the first time the ability to determine the space group from reciprocal space data using this hybrid approach was shown. Transfer of molecular C2 symmetry into P2/c packing symmetry provided a connection across length scales to overcome both lack of long‐range order and missing diffraction‐phase information. Refinement with heteronuclear distance constraints confirmed the racemic P2/c packing that was scaffolded by molecular recognition of salphen zinc in a pseudo‐octahedral environment with bromide and with alkyl chains folding along the phenazine. The NDI light‐harvesting stacks ran orthogonal to the intermolecular electric dipole moment present in the solid. Finally, the orientation of flexible lamellae on an electrode surface was determined.
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Affiliation(s)
- Brijith Thomas
- Leiden Institute of Chemistry, Einsteinweg 55, 2333CC, Leiden, The Netherlands
| | - Jeroen Rombouts
- Vrije University Amsterdam, De Boelelaan 1083, 1081 HV, Amsterdam, The Netherlands
| | - Gert T Oostergetel
- Groningen Biomolecular Sciences and Biotechnology Institute, Nijenborgh 7, 9747 AG, Groningen, The Netherlands
| | | | - Francesco Buda
- Leiden Institute of Chemistry, Einsteinweg 55, 2333CC, Leiden, The Netherlands
| | - Koop Lammertsma
- Vrije University Amsterdam, De Boelelaan 1083, 1081 HV, Amsterdam, The Netherlands.,Department of Chemistry, University of Johannesburg, Auckland Park, Johannesburg, 2006, South Africa
| | - Romano Orru
- Vrije University Amsterdam, De Boelelaan 1083, 1081 HV, Amsterdam, The Netherlands
| | - Huub J M de Groot
- Leiden Institute of Chemistry, Einsteinweg 55, 2333CC, Leiden, The Netherlands
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23
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Wiegand T, Cadalbert R, Gardiennet C, Timmins J, Terradot L, Böckmann A, Meier BH. Monitoring ssDNA Binding to the DnaB Helicase from Helicobacter pylori by Solid-State NMR Spectroscopy. Angew Chem Int Ed Engl 2016; 55:14164-14168. [PMID: 27709753 DOI: 10.1002/anie.201607295] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 08/23/2016] [Indexed: 11/11/2022]
Abstract
DnaB helicases are bacterial, ATP-driven enzymes that unwind double-stranded DNA during DNA replication. Herein, we study the sequential binding of the "non-hydrolysable" ATP analogue AMP-PNP and of single-stranded (ss) DNA to the dodecameric DnaB helicase from Helicobacter pylori using solid-state NMR. Phosphorus cross-polarization experiments monitor the binding of AMP-PNP and DNA to the helicase. 13 C chemical-shift perturbations (CSPs) are used to detect conformational changes in the protein upon binding. The helicase switches upon AMP-PNP addition into a conformation apt for ssDNA binding, and AMP-PNP is hydrolyzed and released upon binding of ssDNA. Our study sheds light on the conformational changes which are triggered by the interaction with AMP-PNP and are needed for ssDNA binding of H. pylori DnaB in vitro. They also demonstrate the level of detail solid-state NMR can provide for the characterization of protein-DNA interactions and the interplay with ATP or its analogues.
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Affiliation(s)
- Thomas Wiegand
- Physical Chemistry, ETH Zurich, 8093, Zurich, Switzerland
| | | | - Carole Gardiennet
- Institut de Biologie et Chimie des Protéines, Molecular Microbiology and Structural Biochemistry, UMR 5086 CNRS, Université de Lyon, 7 passage du Vercors, 69367, Lyon, France.,CRM2, UMR 7036 CNRS/, Université de Lorraine, Faculté des Sciences et Technologies, BP 70239, Boulevard des Aiguillettes, 54506, Vandoeuvre-lès-Nancy, France
| | - Joanna Timmins
- Univ. Grenoble Alpes, CEA,CNRS, F-, 38044, Grenoble, France
| | - Laurent Terradot
- Institut de Biologie et Chimie des Protéines, Molecular Microbiology and Structural Biochemistry, UMR 5086 CNRS, Université de Lyon, 7 passage du Vercors, 69367, Lyon, France.
| | - Anja Böckmann
- Institut de Biologie et Chimie des Protéines, Molecular Microbiology and Structural Biochemistry, UMR 5086 CNRS, Université de Lyon, 7 passage du Vercors, 69367, Lyon, France.
| | - Beat H Meier
- Physical Chemistry, ETH Zurich, 8093, Zurich, Switzerland.
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24
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Andreas LB, Jaudzems K, Stanek J, Lalli D, Bertarello A, Le Marchand T, Cala-De Paepe D, Kotelovica S, Akopjana I, Knott B, Wegner S, Engelke F, Lesage A, Emsley L, Tars K, Herrmann T, Pintacuda G. Structure of fully protonated proteins by proton-detected magic-angle spinning NMR. Proc Natl Acad Sci U S A 2016; 113:9187-92. [PMID: 27489348 DOI: 10.1073/pnas.1602248113] [Citation(s) in RCA: 184] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Protein structure determination by proton-detected magic-angle spinning (MAS) NMR has focused on highly deuterated samples, in which only a small number of protons are introduced and observation of signals from side chains is extremely limited. Here, we show in two fully protonated proteins that, at 100-kHz MAS and above, spectral resolution is high enough to detect resolved correlations from amide and side-chain protons of all residue types, and to reliably measure a dense network of (1)H-(1)H proximities that define a protein structure. The high data quality allowed the correct identification of internuclear distance restraints encoded in 3D spectra with automated data analysis, resulting in accurate, unbiased, and fast structure determination. Additionally, we find that narrower proton resonance lines, longer coherence lifetimes, and improved magnetization transfer offset the reduced sample size at 100-kHz spinning and above. Less than 2 weeks of experiment time and a single 0.5-mg sample was sufficient for the acquisition of all data necessary for backbone and side-chain resonance assignment and unsupervised structure determination. We expect the technique to pave the way for atomic-resolution structure analysis applicable to a wide range of proteins.
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25
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Kempgens P, Britton J. Powder-XRD and (14) N magic angle-spinning solid-state NMR spectroscopy of some metal nitrides. Magn Reson Chem 2016; 54:371-376. [PMID: 26687421 DOI: 10.1002/mrc.4395] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 11/02/2015] [Accepted: 11/10/2015] [Indexed: 06/05/2023]
Abstract
Some metal nitrides (TiN, ZrN, InN, GaN, Ca3 N2 , Mg3 N2 , and Ge3 N4 ) have been studied by powder X-ray diffraction (XRD) and (14) N magic angle-spinning (MAS) solid-state NMR spectroscopy. For Ca3 N2 , Mg3 N2 , and Ge3 N4 , no (14) N NMR signal was observed. Low speed (νr = 2 kHz for TiN, ZrN, and GaN; νr = 1 kHz for InN) and 'high speed' (νr = 15 kHz for TiN; νr = 5 kHz for ZrN; νr = 10 kHz for InN and GaN) MAS NMR experiments were performed. For TiN, ZrN, InN, and GaN, powder-XRD was used to identify the phases present in each sample. The number of peaks observed for each sample in their (14) N MAS solid-state NMR spectrum matches perfectly well with the number of nitrogen-containing phases identified by powder-XRD. The (14) N MAS solid-state NMR spectra are symmetric and dominated by the quadrupolar interaction. The envelopes of the spinning sidebands manifold are Lorentzian, and it is concluded that there is a distribution of the quadrupolar coupling constants Qcc 's arising from structural defects in the compounds studied.
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Affiliation(s)
- Pierre Kempgens
- Department of Chemistry, Rhodes University, Grahamstown, 6140, South Africa
| | - Jonathan Britton
- Department of Chemistry, Rhodes University, Grahamstown, 6140, South Africa
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26
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Lamley JM, Öster C, Stevens RA, Lewandowski JR. Intermolecular Interactions and Protein Dynamics by Solid-State NMR Spectroscopy. Angew Chem Int Ed Engl 2015; 54:15374-8. [PMID: 26537742 PMCID: PMC4736466 DOI: 10.1002/anie.201509168] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Indexed: 11/23/2022]
Abstract
Understanding the dynamics of interacting proteins is a crucial step toward describing many biophysical processes. Here we investigate the backbone dynamics for protein GB1 in two different assemblies: crystalline GB1 and the precipitated GB1–antibody complex with a molecular weight of more than 300 kDa. We perform these measurements on samples containing as little as eight nanomoles of GB1. From measurements of site‐specific 15N relaxation rates including relaxation dispersion we obtain snapshots of dynamics spanning nine orders of magnitude in terms of the time scale. A comparison of measurements for GB1 in either environment reveals that while many of the dynamic features of the protein are conserved between them (in particular for the fast picosecond–nanosecond motions), much greater differences occur for slow motions with motions in the >500 ns range being more prevalent in the complex. The data suggest that GB1 can potentially undergo a small‐amplitude overall anisotropic motion sampling the interaction interface in the complex.
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Affiliation(s)
- Jonathan M Lamley
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL (UK)
| | - Carl Öster
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL (UK)
| | - Rebecca A Stevens
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL (UK)
| | - Józef R Lewandowski
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL (UK).
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27
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Morag O, Sgourakis NG, Baker D, Goldbourt A. The NMR-Rosetta capsid model of M13 bacteriophage reveals a quadrupled hydrophobic packing epitope. Proc Natl Acad Sci U S A 2015; 112:971-6. [PMID: 25587134 PMCID: PMC4313819 DOI: 10.1073/pnas.1415393112] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Filamentous phage are elongated semiflexible ssDNA viruses that infect bacteria. The M13 phage, belonging to the family inoviridae, has a length of ∼1 μm and a diameter of ∼7 nm. Here we present a structural model for the capsid of intact M13 bacteriophage using Rosetta model building guided by structure restraints obtained from magic-angle spinning solid-state NMR experimental data. The C5 subunit symmetry observed in fiber diffraction studies was enforced during model building. The structure consists of stacked pentamers with largely alpha helical subunits containing an N-terminal type II β-turn; there is a rise of 16.6-16.7 Å and a tilt of 36.1-36.6° between consecutive pentamers. The packing of the subunits is stabilized by a repeating hydrophobic stacking pocket; each subunit participates in four pockets by contributing different hydrophobic residues, which are spread along the subunit sequence. Our study provides, to our knowledge, the first magic-angle spinning NMR structure of an intact filamentous virus capsid and further demonstrates the strength of this technique as a method of choice to study noncrystalline, high-molecular-weight molecular assemblies.
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Affiliation(s)
- Omry Morag
- School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Ramat Aviv 69978, Tel Aviv, Israel; and
| | | | - David Baker
- Department of Biochemistry, University of Washington, Seattle, WA 98195
| | - Amir Goldbourt
- School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Ramat Aviv 69978, Tel Aviv, Israel; and
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28
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Sengupta I, Gao M, Arachchige RJ, Nadaud PS, Cunningham TF, Saxena S, Schwieters CD, Jaroniec CP. Protein structural studies by paramagnetic solid-state NMR spectroscopy aided by a compact cyclen-type Cu(II) binding tag. J Biomol NMR 2015; 61:1-6. [PMID: 25432438 PMCID: PMC4304965 DOI: 10.1007/s10858-014-9880-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 11/18/2014] [Indexed: 05/07/2023]
Abstract
Paramagnetic relaxation enhancements (PREs) are a rich source of structural information in protein solid-state NMR spectroscopy. Here we demonstrate that PRE measurements in natively diamagnetic proteins are facilitated by a thiol-reactive compact, cyclen-based, high-affinity Cu(2+) binding tag, 1-[2-(pyridin-2-yldisulfanyl)ethyl]-1,4,7,10-tetraazacyclododecane (TETAC), that overcomes the key shortcomings associated with the use of larger, more flexible metal-binding tags. Using the TETAC-Cu(2+) K28C mutant of B1 immunoglobulin-binding domain of protein G as a model, we find that amino acid residues located within ~10 Å of the Cu(2+) center experience considerable transverse PREs leading to severely attenuated resonances in 2D (15)N-(13)C correlation spectra. For more distant residues, electron-nucleus distances are accessible via quantitative measurements of longitudinal PREs, and we demonstrate such measurements for (15)N-Cu(2+) distances up to ~20 Å.
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Affiliation(s)
- Ishita Sengupta
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Min Gao
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Rajith J. Arachchige
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Philippe S. Nadaud
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Timothy F. Cunningham
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Sunil Saxena
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Charles D. Schwieters
- Center for Information Technology, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Christopher P. Jaroniec
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
- Corresponding author: Christopher P. Jaroniec,
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29
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Niu Z, Zhao W, Zhang Z, Xiao F, Tang X, Yang J. The molecular structure of Alzheimer β-amyloid fibrils formed in the presence of phospholipid vesicles. Angew Chem Int Ed Engl 2014; 53:9294-7. [PMID: 24810551 DOI: 10.1002/anie.201311106] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2013] [Indexed: 11/06/2022]
Abstract
β-amyloid (Aβ) fibrils are the major species involved in Alzheimer's disease (AD). An atomic-resolution molecular structure of Aβ40 fibrils formed in the presence of lipid vesicles was obtained by using magic angle spinning (MAS) solid-state NMR spectroscopy. The fibril structures formed in the presence of the lipid vesicles are remarkably different from those formed in solution. These results provide insights into the molecular mechanism of Aβ aggregation in the presence of lipid vesicles.
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Affiliation(s)
- Zheng Niu
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071 (P.R. China)
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30
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Affiliation(s)
- Eric D Watt
- Department of Chemistry, ‡Department of Biochemistry, and §Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign , 600 South Mathews Avenue, Urbana, Illinois 61801, Unites States
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31
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Lin P, Chen X, Moktan H, Arrese EL, Duan L, Wang L, Soulages JL, Zhou DH. Membrane attachment and structure models of lipid storage droplet protein 1. Biochim Biophys Acta 2013; 1838:874-81. [PMID: 24333382 DOI: 10.1016/j.bbamem.2013.12.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Revised: 11/29/2013] [Accepted: 12/05/2013] [Indexed: 02/08/2023]
Abstract
Neutral lipid triglycerides, a main reserve for fat and energy, are stored in organelles called lipid droplets. The storage and release of triglycerides are actively regulated by several proteins specific to the droplet surface, one of which in insects is PLIN1. PLIN1 plays a key role in the activation of triglyceride hydrolysis upon phosphorylation. However, the structure of PLIN1 and its relation to functions remain elusive due to its insolubility and crystallization difficulty. Here we report the first solid-state NMR study on the Drosophila melanogaster PLIN1 in combination with molecular dynamics simulation to show the structural basis for its lipid droplet attachment. NMR spin diffusion experiments were consistent with the predicted membrane attachment motif of PLIN1. The data indicated that PLIN1 has close contact with the terminal methyl groups of the phospholipid acyl chains. Structure models for the membrane attachment motif were generated based on hydrophobicity analysis and NMR membrane insertion depth information. Simulated NMR spectra from a trans-model agreed with experimental spectra. In this model, lipids from the bottom leaflet were very close to the surface in the region enclosed by membrane attachment motif. This may imply that in real lipid droplet, triglyceride molecules might be brought close to the surface by the same mechanism, ready to leave the droplet in the event of lipolysis. Juxtaposition of triglyceride lipase structure to the trans-model suggested a possible interaction of a conserved segment with the lipase by electrostatic interactions, opening the lipase lid to expose the catalytic center.
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Affiliation(s)
- Penghui Lin
- Department of Physics, 230 L Henry Bellmon Research Center, Oklahoma State University, Stillwater, OK 74078, USA
| | - Xiao Chen
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Hem Moktan
- Department of Physics, 230 L Henry Bellmon Research Center, Oklahoma State University, Stillwater, OK 74078, USA
| | - Estela L Arrese
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Lian Duan
- Department of Physics, 230 L Henry Bellmon Research Center, Oklahoma State University, Stillwater, OK 74078, USA
| | - Liying Wang
- Department of Physics, 230 L Henry Bellmon Research Center, Oklahoma State University, Stillwater, OK 74078, USA; State Key Laboratory of Magnetic Resonance and Atomic Molecular Physics, Wuhan Center for Magnetic Resonance, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Jose L Soulages
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Donghua H Zhou
- Department of Physics, 230 L Henry Bellmon Research Center, Oklahoma State University, Stillwater, OK 74078, USA.
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32
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Abstract
Bone minerals possess two primary hydrogen sources: hydroxide ions in the nanocrystalline core and structural water in the amorphous surface layer. In order to accurately measure their concentrations using hydrogen to phosphorus cross polarization NMR spectroscopy, it is necessary to analyze the dependence of signal intensities on serial contact times, namely, cross polarization kinetics. A reliable protocol is developed to iteratively decompose the severely overlapped spectra and to analyze the cross-polarization kinetics, leading to measurement of hydroxyl and structural water concentrations. Structural water concentration is used to estimate mineral specific surface area and nanocrystal thickness for intact bone.
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Affiliation(s)
- Amanda J Taylor
- Department of Physics, Oklahoma State University, Stillwater, OK, USA 74078
| | - Elizabeth Rendina
- Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK, USA 74078
| | - Brenda J Smith
- Department of Nutritional Sciences, Oklahoma State University, Stillwater, OK, USA 74078
| | - Donghua H Zhou
- Department of Physics, Oklahoma State University, Stillwater, OK, USA 74078
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33
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McCrate OA, Zhou X, Reichhardt C, Cegelski L. Sum of the parts: composition and architecture of the bacterial extracellular matrix. J Mol Biol 2013; 425:4286-94. [PMID: 23827139 PMCID: PMC3812305 DOI: 10.1016/j.jmb.2013.06.022] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 06/06/2013] [Indexed: 11/18/2022]
Abstract
Bacterial biofilms are complex multicellular assemblies that exhibit resistance to antibiotics and contribute to the pathogenesis of serious and chronic infectious diseases. New approaches and quantitative data are needed to define the molecular composition of bacterial biofilms. Escherichia coli biofilms are known to contain polysaccharides and functional amyloid fibers termed curli, yet accurate determinations of biofilm composition at the molecular level have been elusive. The ability to define the composition of the extracellular matrix (ECM) is crucial for the elucidation of structure-function relationships that will aid the development of chemical strategies to disrupt biofilms. We have developed an approach that integrates non-perturbative preparation of the ECM with electron microscopy, biochemistry, and solid-state NMR spectroscopy to define the chemical composition of the intact and insoluble ECM of a clinically important pathogenic bacterium--uropathogenic E. coli. Our data permitted a sum-of-all-the-parts analysis. Electron microscopy revealed supramolecular shell-like structures that encapsulated single cells and enmeshed the bacterial community. Biochemical and solid-state NMR measurements of the matrix and constitutive parts established that the matrix is composed of two major components, curli and cellulose, each in a quantifiable amount. This approach to quantifying the matrix composition is widely applicable to other organisms and to examining the influence of biofilm inhibitors. Collectively, our NMR spectra and the electron micrographs of the purified ECM inspire us to consider the biofilm matrix not as an undefined slime, but as an assembly of polymers with a defined composition and architecture.
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Affiliation(s)
| | | | | | - Lynette Cegelski
- Department of Chemistry, Stanford University, Stanford, CA 94305
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34
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Mainz A, Religa TL, Sprangers R, Linser R, Kay LE, Reif B. NMR spectroscopy of soluble protein complexes at one mega-dalton and beyond. Angew Chem Int Ed Engl 2013; 52:8746-51. [PMID: 23873792 DOI: 10.1002/anie.201301215] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Revised: 04/30/2013] [Indexed: 01/07/2023]
Affiliation(s)
- Andi Mainz
- Munich Center for Integrated Protein Science at the Department Chemie, Technische Universität München, Lichtenbergstrasse 4, 85747 Garching, Germany
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35
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Wang T, Yao H, Hong M. Determining the depth of insertion of dynamically invisible membrane peptides by gel-phase ¹H spin diffusion heteronuclear correlation NMR. J Biomol NMR 2013; 56:139-148. [PMID: 23606274 PMCID: PMC3700645 DOI: 10.1007/s10858-013-9730-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2013] [Accepted: 04/10/2013] [Indexed: 05/28/2023]
Abstract
Solid-state NMR determination of the depth of insertion of membrane peptides and proteins has so far utilized (1)H spin diffusion and paramagnetic relaxation enhancement experiments, which are typically conducted in the liquid-crystalline phase of the lipid bilayer. For membrane proteins or peptide assemblies that undergo intermediate-timescale motion in the liquid-crystalline membrane, these approaches are no longer applicable because the protein signals are broadened beyond detection. Here we show that the rigid-solid HETCOR experiment, with an additional spin diffusion period, can be used to determine the depth of proteins in gel-phase lipid membranes, where the proteins are immobilized to give high-intensity solid-state NMR spectra. Demonstration on two membrane peptides with known insertion depths shows that well-inserted peptides give rise to high lipid cross peak intensities and low water cross peaks within a modest spin diffusion mixing time, while surface-bound peptides have higher water than lipid cross peaks. Furthermore, well-inserted membrane peptides have nearly identical (1)H cross sections as the lipid chains, indicating equilibration of the peptide and lipid magnetization. Using this approach, we measured the membrane topology of the α-helical fusion peptide of the paramyxovirus, PIV5, in the anionic POPC/POPG membrane, in which the peptide undergoes intermediate-timescale motion at physiological temperature. The gel-phase HETCOR spectra indicate that the α-helical fusion peptide is well inserted into the POPC/POPG bilayer, spanning both leaflets. This insertion motif gives insight into the functional role of the α-helical PIV5 fusion peptide in virus-cell membrane fusion.
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Affiliation(s)
| | | | - M. Hong
- Corresponding author: Mei Hong Tel: 515-294-3521, Fax: 515-294-0105,
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36
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Leftin A, Job C, Beyer K, Brown MF. Solid-state ¹³C NMR reveals annealing of raft-like membranes containing cholesterol by the intrinsically disordered protein α-Synuclein. J Mol Biol 2013; 425:2973-87. [PMID: 23583776 DOI: 10.1016/j.jmb.2013.04.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2012] [Revised: 03/14/2013] [Accepted: 04/02/2013] [Indexed: 11/20/2022]
Abstract
Misfolding and aggregation of the intrinsically disordered protein α-Synuclein (αS) in Lewy body plaques are characteristic markers of late-stage Parkinson's disease. It is well established that membrane binding is initiated at the N-terminus of the protein and affects biasing of conformational ensembles of αS. However, little is understood about the effect of αS on the membrane lipid bilayer. One hypothesis is that intrinsically disordered αS alters the structural properties of the membrane, thereby stabilizing the bilayer against fusion. Here, we used two-dimensional (13)C separated local-field NMR to study interaction of the wild-type α-Synuclein (wt-αS) or its N-terminal (1-25) amino acid sequence (N-αS) with a cholesterol-enriched ternary membrane system. This lipid bilayer mimics cellular raft-like domains in the brain that are proposed to be involved in neuronal membrane fusion. The two-dimensional dipolar-recoupling pulse sequence DROSS (dipolar recoupling on-axis with scaling and shape preservation) was implemented to measure isotropic (13)C chemical shifts and (13)C-(1)H residual dipolar couplings under magic-angle spinning. Site-specific changes in NMR chemical shifts and segmental order parameters indicate that both wt-αS and N-αS bind to the membrane interface and change lipid packing within raft-like membranes. Mean-torque modeling of (13)C-(1)H NMR order parameters shows that αS induces a remarkable thinning of the bilayer (≈6Å), accompanied by an increase in phospholipid cross-sectional area (≈10Å(2)). This perturbation is characterized as membrane annealing and entails structural remodeling of the raft-like liquid-ordered phase. We propose this process is implicated in regulation of synaptic membrane fusion that may be altered by aggregation of αS in Parkinson's disease.
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37
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Zhou DH, Nieuwkoop AJ, Berthold DA, Comellas G, Sperling LJ, Tang M, Shah GJ, Brea EJ, Lemkau LR, Rienstra CM. Solid-state NMR analysis of membrane proteins and protein aggregates by proton detected spectroscopy. J Biomol NMR 2012; 54:291-305. [PMID: 22986689 PMCID: PMC3484199 DOI: 10.1007/s10858-012-9672-z] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2012] [Accepted: 09/05/2012] [Indexed: 05/04/2023]
Abstract
Solid-state NMR has emerged as an important tool for structural biology and chemistry, capable of solving atomic-resolution structures for proteins in membrane-bound and aggregated states. Proton detection methods have been recently realized under fast magic-angle spinning conditions, providing large sensitivity enhancements for efficient examination of uniformly labeled proteins. The first and often most challenging step of protein structure determination by NMR is the site-specific resonance assignment. Here we demonstrate resonance assignments based on high-sensitivity proton-detected three-dimensional experiments for samples of different physical states, including a fully-protonated small protein (GB1, 6 kDa), a deuterated microcrystalline protein (DsbA, 21 kDa), a membrane protein (DsbB, 20 kDa) prepared in a lipid environment, and the extended core of a fibrillar protein (α-synuclein, 14 kDa). In our implementation of these experiments, including CONH, CO(CA)NH, CANH, CA(CO)NH, CBCANH, and CBCA(CO)NH, dipolar-based polarization transfer methods have been chosen for optimal efficiency for relatively high protonation levels (full protonation or 100 % amide proton), fast magic-angle spinning conditions (40 kHz) and moderate proton decoupling power levels. Each H-N pair correlates exclusively to either intra- or inter-residue carbons, but not both, to maximize spectral resolution. Experiment time can be reduced by at least a factor of 10 by using proton detection in comparison to carbon detection. These high-sensitivity experiments are especially important for membrane proteins, which often have rather low expression yield. Proton-detection based experiments are expected to play an important role in accelerating protein structure elucidation by solid-state NMR with the improved sensitivity and resolution.
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Affiliation(s)
- Donghua H. Zhou
- Department of Physics, Oklahoma State University, Stillwater, OK 74074, USA,
| | - Andrew J. Nieuwkoop
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA
- Leibniz-Institut für Molekulare Pharmakologie, 13125 Berlin, Germany
| | - Deborah A. Berthold
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA
| | - Gemma Comellas
- Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA
| | - Lindsay J. Sperling
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Ming Tang
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA
| | - Gautam J. Shah
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA
| | - Elliott J. Brea
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA
| | - Luisel R. Lemkau
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA
| | - Chad M. Rienstra
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA
- Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA
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38
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Cukkemane A, Nand D, Gradmann S, Weingarth M, Kaupp UB, Baldus M. Solid-state NMR [13C,15N] resonance assignments of the nucleotide-binding domain of a bacterial cyclic nucleotide-gated channel. Biomol NMR Assign 2012; 6:225-9. [PMID: 22302441 PMCID: PMC3438399 DOI: 10.1007/s12104-012-9363-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 01/17/2012] [Indexed: 05/21/2023]
Abstract
Channels regulated by cyclic nucleotides are key signalling proteins in several biological pathways. The regulatory aspect is conferred by a C-terminal cyclic nucleotide-binding domain (CNBD). We report resonance assignments of the CNBD of a bacterial mlCNG channel obtained using 2D and 3D solid-state NMR under Magic-angle Spinning conditions. A secondary chemical shift analysis of the 141 residue protein suggests a three-dimensional fold seen in earlier X-ray and solution-state NMR work and points to spectroscopic polymorphism for a selected set of resonances.
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Affiliation(s)
- Abhishek Cukkemane
- Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Deepak Nand
- Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Sabine Gradmann
- Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Markus Weingarth
- Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - U. Benjamin Kaupp
- Center of Advanced European Studies and Research (Caesar), Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
| | - Marc Baldus
- Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
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39
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Hu KN, Qiang W, Bermejo GA, Schwieters CD, Tycko R. Restraints on backbone conformations in solid state NMR studies of uniformly labeled proteins from quantitative amide 15N-15N and carbonyl 13C-13C dipolar recoupling data. J Magn Reson 2012; 218:115-27. [PMID: 22449573 PMCID: PMC3568759 DOI: 10.1016/j.jmr.2012.03.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Accepted: 03/01/2012] [Indexed: 05/04/2023]
Abstract
Recent structural studies of uniformly (15)N, (13)C-labeled proteins by solid state nuclear magnetic resonance (NMR) rely principally on two sources of structural restraints: (i) restraints on backbone conformation from isotropic (15)N and (13)C chemical shifts, based on empirical correlations between chemical shifts and backbone torsion angles; (ii) restraints on inter-residue proximities from qualitative measurements of internuclear dipole-dipole couplings, detected as the presence or absence of inter-residue crosspeaks in multidimensional spectra. We show that site-specific dipole-dipole couplings among (15)N-labeled backbone amide sites and among (13)C-labeled backbone carbonyl sites can be measured quantitatively in uniformly-labeled proteins, using dipolar recoupling techniques that we call (15)N-BARE and (13)C-BARE (BAckbone REcoupling), and that the resulting data represent a new source of restraints on backbone conformation. (15)N-BARE and (13)C-BARE data can be incorporated into structural modeling calculations as potential energy surfaces, which are derived from comparisons between experimental (15)N and (13)C signal decay curves, extracted from crosspeak intensities in series of two-dimensional spectra, with numerical simulations of the (15)N-BARE and (13)C-BARE measurements. We demonstrate this approach through experiments on microcrystalline, uniformly (15)N, (13)C-labeled protein GB1. Results for GB1 show that (15)N-BARE and (13)C-BARE restraints are complementary to restraints from chemical shifts and inter-residue crosspeaks, improving both the precision and the accuracy of calculated structures.
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Affiliation(s)
- Kan-Nian Hu
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0520, United States
| | - Wei Qiang
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0520, United States
| | - Guillermo A. Bermejo
- Division of Computational Bioscience, Center for Information Technology, National Institutes of Health, Bethesda, MD 20892-5624, United States
| | - Charles D. Schwieters
- Division of Computational Bioscience, Center for Information Technology, National Institutes of Health, Bethesda, MD 20892-5624, United States
| | - Robert Tycko
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0520, United States
- Corresponding author. Address: National Institutes of Health, Building 5, Room 112, Bethesda, MD 20892-0520, United States. Fax: +1 301 496 0825. , (R. Tycko)
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40
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Abstract
We review the current state of membrane protein structure determination using solid-state nuclear magnetic resonance (NMR) spectroscopy. Multidimensional magic-angle-spinning correlation NMR combined with oriented-sample experiments has made it possible to measure a full panel of structural constraints of membrane proteins directly in lipid bilayers. These constraints include torsion angles, interatomic distances, oligomeric structure, protein dynamics, ligand structure and dynamics, and protein orientation and depth of insertion in the lipid bilayer. Using solid-state NMR, researchers have studied potassium channels, proton channels, Ca(2+) pumps, G protein-coupled receptors, bacterial outer membrane proteins, and viral fusion proteins to elucidate their mechanisms of action. Many of these membrane proteins have also been investigated in detergent micelles using solution NMR. Comparison of the solid-state and solution NMR structures provides important insights into the effects of the solubilizing environment on membrane protein structure and dynamics.
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Affiliation(s)
- Mei Hong
- Department of Chemistry, Iowa State University, Ames, 50011, USA.
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41
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Comellas G, Lemkau LR, Nieuwkoop AJ, Kloepper KD, Ladror DT, Ebisu R, Woods WS, Lipton AS, George JM, Rienstra CM. Structured regions of α-synuclein fibrils include the early-onset Parkinson's disease mutation sites. J Mol Biol 2011; 411:881-95. [PMID: 21718702 PMCID: PMC3157309 DOI: 10.1016/j.jmb.2011.06.026] [Citation(s) in RCA: 128] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2011] [Revised: 06/07/2011] [Accepted: 06/15/2011] [Indexed: 11/20/2022]
Abstract
α-Synuclein (AS) fibrils are the major component of Lewy bodies, the pathological hallmark of Parkinson's disease (PD). Here, we use results from an extensive investigation employing solid-state NMR to present a detailed structural characterization and conformational dynamics quantification of full-length AS fibrils. Our results show that the core extends with a repeated structural motif. This result disagrees with the previously proposed fold of AS fibrils obtained with limited solid-state NMR data. Additionally, our results demonstrate that the three single point mutations associated with early-onset PD-A30P, E46K and A53T-are located in structured regions. We find that E46K and A53T mutations, located in rigid β-strands of the wild-type fibrils, are associated with major and minor structural perturbations, respectively.
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Affiliation(s)
- Gemma Comellas
- Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois, 61801, USA
| | - Luisel R. Lemkau
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois, 61801, USA
| | - Andrew J. Nieuwkoop
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois, 61801, USA
| | - Kathryn D. Kloepper
- Department of Chemistry, Mercer University, 1400 Coleman Avenue, Macon, Georgia, 31207, USA
| | - Daniel T. Ladror
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois, 61801, USA
| | - Reika Ebisu
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois, 61801, USA
| | - Wendy S. Woods
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois, 61801, USA
| | - Andrew S. Lipton
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington, 99352, USA
| | - Julia M. George
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois, 61801, USA
| | - Chad M. Rienstra
- Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois, 61801, USA
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois, 61801, USA
- Department of Biochemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois, 61801, USA
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42
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Hu KN, Qiang W, Tycko R. A general Monte Carlo/simulated annealing algorithm for resonance assignment in NMR of uniformly labeled biopolymers. J Biomol NMR 2011; 50:267-76. [PMID: 21710190 PMCID: PMC3199575 DOI: 10.1007/s10858-011-9517-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Accepted: 05/09/2011] [Indexed: 05/05/2023]
Abstract
We describe a general computational approach to site-specific resonance assignments in multidimensional NMR studies of uniformly (15)N,(13)C-labeled biopolymers, based on a simple Monte Carlo/simulated annealing (MCSA) algorithm contained in the program MCASSIGN2. Input to MCASSIGN2 includes lists of multidimensional signals in the NMR spectra with their possible residue-type assignments (which need not be unique), the biopolymer sequence, and a table that describes the connections that relate one signal list to another. As output, MCASSIGN2 produces a high-scoring sequential assignment of the multidimensional signals, using a score function that rewards good connections (i.e., agreement between relevant sets of chemical shifts in different signal lists) and penalizes bad connections, unassigned signals, and assignment gaps. Examination of a set of high-scoring assignments from a large number of independent runs allows one to determine whether a unique assignment exists for the entire sequence or parts thereof. We demonstrate the MCSA algorithm using two-dimensional (2D) and three-dimensional (3D) solid state NMR spectra of several model protein samples (α-spectrin SH3 domain and protein G/B1 microcrystals, HET-s(218-289) fibrils), obtained with magic-angle spinning and standard polarization transfer techniques. The MCSA algorithm and MCASSIGN2 program can accommodate arbitrary combinations of NMR spectra with arbitrary dimensionality, and can therefore be applied in many areas of solid state and solution NMR.
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Affiliation(s)
- Kan-Nian Hu
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0520, USA
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43
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Comellas G, Lopez JJ, Nieuwkoop AJ, Lemkau LR, Rienstra CM. Straightforward, effective calibration of SPINAL-64 decoupling results in the enhancement of sensitivity and resolution of biomolecular solid-state NMR. J Magn Reson 2011; 209:131-5. [PMID: 21296014 PMCID: PMC3065959 DOI: 10.1016/j.jmr.2010.12.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Revised: 12/21/2010] [Accepted: 12/28/2010] [Indexed: 05/11/2023]
Abstract
We describe a simple yet highly effective optimization strategy for SPINAL-64 ¹H decoupling conditions for magic-angle spinning solid-state NMR. With adjustment of the phase angles in a coupled manner, the optimal conditions resulting from three parameter optimizations can be determined with adjustment of a single phase. Notably, echo T₂ relaxation times for ¹³C and ¹⁵N show significant enhancement (up to 64%), relative to the previous described SPINAL-64 conditions, under the moderate ¹H decoupling levels (60-100 kHz) and MAS rate (13.3 kHz) commonly employed for high-resolution SSNMR spectroscopy of proteins. Additionally, we also investigated the effect at higher spinning rate (33.3 kHz) and compared the results with other ¹H decoupling schemes (TPPM, XiX), as well as SPINAL-64 with the originally reported optimal values.
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Affiliation(s)
- Gemma Comellas
- Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801
| | - Jakob J. Lopez
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801
| | - Andrew J. Nieuwkoop
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801
| | - Luisel R. Lemkau
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801
| | - Chad M. Rienstra
- Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801
- Department of Biochemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801
- Corresponding author information: Chad M. Rienstra, Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA. Telephone: (+01) 217 244-4655. Fax: 217 244-3186.
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44
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Franks WT, Atreya HS, Szyperski T, Rienstra CM. GFT projection NMR spectroscopy for proteins in the solid state. J Biomol NMR 2010; 48:213-23. [PMID: 21052779 PMCID: PMC3058792 DOI: 10.1007/s10858-010-9451-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2010] [Accepted: 09/26/2010] [Indexed: 05/12/2023]
Abstract
Recording of four-dimensional (4D) spectra for proteins in the solid state has opened new avenues to obtain virtually complete resonance assignments and three-dimensional (3D) structures of proteins. As in solution state NMR, the sampling of three indirect dimensions leads per se to long minimal measurement time. Furthermore, artifact suppression in solid state NMR relies primarily on radio-frequency pulse phase cycling. For an n-step phase cycle, the minimal measurement times of both 3D and 4D spectra are increased n times. To tackle the associated 'sampling problem' and to avoid sampling limited data acquisition, solid state G-Matrix Fourier Transform (SS GFT) projection NMR is introduced to rapidly acquire 3D and 4D spectral information. Specifically, (4,3)D (HA)CANCOCX and (3,2)D (HACA)NCOCX were implemented and recorded for the 6 kDa protein GB1 within about 10% of the time required for acquiring the conventional congeners with the same maximal evolution times and spectral widths in the indirect dimensions. Spectral analysis was complemented by comparative analysis of expected spectral congestion in conventional and GFT NMR experiments, demonstrating that high spectral resolution of the GFT NMR experiments enables one to efficiently obtain nearly complete resonance assignments even for large proteins.
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Affiliation(s)
- W. Trent Franks
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Hanudatta S. Atreya
- Department of Chemistry, State University of New York at Buffalo, Buffalo, NY 14260, USA
| | - Thomas Szyperski
- Department of Chemistry, State University of New York at Buffalo, Buffalo, NY 14260, USA
| | - Chad M. Rienstra
- Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA. Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA. Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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45
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Guan X, Stark RE. A general protocol for temperature calibration of MAS NMR probes at arbitrary spinning speeds. Solid State Nucl Magn Reson 2010; 38:74-76. [PMID: 21036557 PMCID: PMC3008415 DOI: 10.1016/j.ssnmr.2010.10.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2010] [Revised: 10/11/2010] [Accepted: 10/13/2010] [Indexed: 05/28/2023]
Abstract
A protocol using (207)Pb NMR of solid lead nitrate was developed to determine the temperature of magic-angle spinning (MAS) NMR probes over a range of nominal set temperatures and spinning speeds. Using BioMAS and FastMAS probes with typical sample spinning rates of 8 and 35 kHz, respectively, empirical equations were devised to predict the respective sample temperatures. These procedures provide a straightforward recipe for temperature calibration of any MAS probe.
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Affiliation(s)
| | - Ruth E. Stark
- Author to whom correspondence should be addressed. ; phone: +1-212-650-8916; FAX: +1-212-650-8719
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46
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Abstract
Charged residues play an important role in defining key mechanistic features in many biomolecules. Determining the pK(a) values of large, membrane or fibrillar proteins can be challenging with traditional methods. In this study we show how solid-state NMR is used to monitor chemical shift changes during a pH titration for the small soluble β1 immunoglobulin binding domain of protein G. The chemical shifts of all the amino acids with charged side-chains throughout the uniformly-(13)C,(15)N-labeled protein were monitored over several samples varying in pH; pK(a) values were determined from these shifts for E27, D36, and E42, and the bounds for the pK(a) of other acidic side-chain resonances were determined. Additionally, this study shows how the calculated pK(a) values give insights into the crystal packing of the protein.
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47
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Sharif S, Kim SJ, Labischinski H, Schaefer J. Characterization of peptidoglycan in fem-deletion mutants of methicillin-resistant Staphylococcus aureus by solid-state NMR. Biochemistry 2009; 48:3100-8. [PMID: 19309106 PMCID: PMC2785074 DOI: 10.1021/bi801750u] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Compositional analysis of the peptidoglycan (PG) of a wild-type methicillin-resistant Staphylococcus aureus and its fem-deletion mutants has been performed on whole cells and cell walls using stable-isotope labeling and rotational-echo double-resonance NMR. The labels included [1-(13)C,(15)N]glycine and l-[epsilon-(15)N]lysine (for a direct measure of the number of glycyl residues in the bridging segment), [1-(13)C]glycine and l-[epsilon-(15)N]lysine (concentration of bridge links), and d-[1-(13)C]alanine and [(15)N]glycine (concentrations of cross-links and wall teichoic acids). The bridging segment length changed from 5.0 glycyl residues (wild-type strain) to 2.5 +/- 0.1 (FemB) with modest changes in cross-link and bridge-link concentrations. This accurate in situ measurement for the FemB mutant indicates a heterogeneous PG structure with 25% monoglycyl and 75% triglycyl bridges. When the bridging segment was reduced to a single glycyl residue 1.0 +/- 0.1 (FemA), the level of cross-linking decreased by more than 20%, resulting in a high concentration of open N-terminal glycyl segments.
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Affiliation(s)
- Shasad Sharif
- Department of Chemistry, Washington University, One Brookings Drive, St. Louis, MO 63130
| | - Sung Joon Kim
- Department of Chemistry, Washington University, One Brookings Drive, St. Louis, MO 63130
| | - Harald Labischinski
- MerLion Pharmaceuticals GmbH, Robert-Rössle-Straβe 10, 13125 Berlin, Germany
| | - Jacob Schaefer
- Department of Chemistry, Washington University, One Brookings Drive, St. Louis, MO 63130
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48
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Cady SD, Mishanina TV, Hong M. Structure of amantadine-bound M2 transmembrane peptide of influenza A in lipid bilayers from magic-angle-spinning solid-state NMR: the role of Ser31 in amantadine binding. J Mol Biol 2009; 385:1127-41. [PMID: 19061899 PMCID: PMC4132896 DOI: 10.1016/j.jmb.2008.11.022] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2008] [Revised: 11/06/2008] [Accepted: 11/12/2008] [Indexed: 01/03/2023]
Abstract
The M2 proton channel of influenza A is the target of the antiviral drugs amantadine and rimantadine, whose effectiveness has been abolished by a single-site mutation of Ser31 to Asn in the transmembrane domain of the protein. Recent high-resolution structures of the M2 transmembrane domain obtained from detergent-solubilized protein in solution and crystal environments gave conflicting drug binding sites. We present magic-angle-spinning solid-state NMR results of Ser31 and a number of other residues in the M2 transmembrane peptide (M2TMP) bound to lipid bilayers. Comparison of the spectra of the membrane-bound apo and complexed M2TMP indicates that Ser31 is the site of the largest chemical shift perturbation by amantadine. The chemical shift constraints lead to a monomer structure with a small kink of the helical axis at Gly34. A tetramer model is then constructed using the helix tilt angle and several interhelical distances previously measured on unoriented bilayer samples. This tetramer model differs from the solution and crystal structures in terms of the openness of the N-terminus of the channel, the constriction at Ser31, and the side-chain conformations of Trp41, a residue important for channel gating. Moreover, the tetramer model suggests that Ser31 may interact with amantadine amine via hydrogen bonding. While the apo and drug-bound M2TMP have similar average structures, the complexed peptide has much narrower linewidths at physiological temperature, indicating drug-induced changes of the protein dynamics in the membrane. Further, at low temperature, several residues show narrower lines in the complexed peptide than the apo peptide, indicating that amantadine binding reduces the conformational heterogeneity of specific residues. The differences of the current solid-state NMR structure of the bilayer-bound M2TMP from the detergent-based M2 structures suggest that the M2 conformation is sensitive to the environment, and care must be taken when interpreting structural findings from non-bilayer samples.
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Affiliation(s)
- Sarah D Cady
- Department of Chemistry, Iowa State University, Ames, IA 50011, USA
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49
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Thurber KR, Tycko R. Measurement of sample temperatures under magic-angle spinning from the chemical shift and spin-lattice relaxation rate of 79Br in KBr powder. J Magn Reson 2009; 196:84-7. [PMID: 18930418 PMCID: PMC2632797 DOI: 10.1016/j.jmr.2008.09.019] [Citation(s) in RCA: 184] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2008] [Revised: 09/22/2008] [Accepted: 09/22/2008] [Indexed: 05/06/2023]
Abstract
Accurate determination of sample temperatures in solid state nuclear magnetic resonance (NMR) with magic-angle spinning (MAS) can be problematic, particularly because frictional heating and heating by radio-frequency irradiation can make the internal sample temperature significantly different from the temperature outside the MAS rotor. This paper demonstrates the use of (79)Br chemical shifts and spin-lattice relaxation rates in KBr powder as temperature-dependent parameters for the determination of internal sample temperatures. Advantages of this method include high signal-to-noise, proximity of the (79)Br NMR frequency to that of (13)C, applicability from 20 K to 320 K or higher, and simultaneity with adjustment of the MAS axis direction. We show that spin-lattice relaxation in KBr is driven by a quadrupolar mechanism. We demonstrate a simple approach to including KBr powder in hydrated samples, such as biological membrane samples, hydrated amyloid fibrils, and hydrated microcrystalline proteins, that allows direct assessment of the effects of frictional and radio-frequency heating under experimentally relevant conditions.
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Affiliation(s)
| | - Robert Tycko
- corresponding author: Dr. Robert Tycko, National Institutes of Health, Building 5, Room 112, Bethesda, MD 20892-0520. phone: 301-402-8272. fax: 301-496-0825. e-mail:
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50
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Breitung ST, Lopez JJ, Dürner G, Glaubitz C, Göbel MW, Suhartono M. A practical synthesis of the 16C/15N-labelled tripeptide N-formyl-Met-Leu-Phe, useful as a reference in solid-state NMR spectroscopy. Beilstein J Org Chem 2008; 4:35. [PMID: 18982075 PMCID: PMC2577282 DOI: 10.3762/bjoc.4.35] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2008] [Accepted: 10/01/2008] [Indexed: 11/29/2022] Open
Abstract
A mild synthetic method for N-formyl-Met-Leu-Phe-OH (1) is described. After Fmoc solid phase peptide synthesis, on-bead formylation and HPLC purification, more than 30 mg of the fully 13C/15N-labelled tripeptide 1 could be isolated in a typical batch. This peptide can be easily crystallised and is therefore well suited as a standard sample for setting up solid-state NMR experiments.
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Affiliation(s)
- Sven T Breitung
- Institute of Organic Chemistry and Chemical Biology, Johann Wolfgang Goethe University Frankfurt, Max-von-Laue-Str. 7, D-60438 Frankfurt am Main, Germany
| | - Jakob J Lopez
- Institute of Biophysical Chemistry, Johann Wolfgang Goethe University Frankfurt, Max-von-Laue-Str. 9, D-60438 Frankfurt am Main, Germany
| | - Gerd Dürner
- Institute of Organic Chemistry and Chemical Biology, Johann Wolfgang Goethe University Frankfurt, Max-von-Laue-Str. 7, D-60438 Frankfurt am Main, Germany
| | - Clemens Glaubitz
- Institute of Biophysical Chemistry, Johann Wolfgang Goethe University Frankfurt, Max-von-Laue-Str. 9, D-60438 Frankfurt am Main, Germany
| | - Michael W Göbel
- Institute of Organic Chemistry and Chemical Biology, Johann Wolfgang Goethe University Frankfurt, Max-von-Laue-Str. 7, D-60438 Frankfurt am Main, Germany
| | - Marcel Suhartono
- Institute of Organic Chemistry and Chemical Biology, Johann Wolfgang Goethe University Frankfurt, Max-von-Laue-Str. 7, D-60438 Frankfurt am Main, Germany
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