51
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Bahramzadeh A, Jiang H, Huber T, Otting G. Two Histidines in an α‐Helix: A Rigid Co
2+
‐Binding Motif for PCS Measurements by NMR Spectroscopy. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201802501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Alireza Bahramzadeh
- Research School of Chemistry The Australian National University Canberra ACT 2601 Australia
| | - Hailun Jiang
- Research School of Chemistry The Australian National University Canberra ACT 2601 Australia
| | - Thomas Huber
- Research School of Chemistry The Australian National University Canberra ACT 2601 Australia
| | - Gottfried Otting
- Research School of Chemistry The Australian National University Canberra ACT 2601 Australia
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52
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Ganser LR, Lee J, Rangadurai A, Merriman DK, Kelly ML, Kansal AD, Sathyamoorthy B, Al-Hashimi HM. High-performance virtual screening by targeting a high-resolution RNA dynamic ensemble. Nat Struct Mol Biol 2018; 25:425-434. [PMID: 29728655 PMCID: PMC5942591 DOI: 10.1038/s41594-018-0062-4] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 03/27/2018] [Indexed: 12/22/2022]
Abstract
Dynamic ensembles hold great promise in advancing RNA-targeted drug discovery. Here we subjected the transactivation response element (TAR) RNA from human immunodeficiency virus type-1 to experimental high-throughput screening against ~100,000 drug-like small molecules. Results were augmented with 170 known TAR-binding molecules and used to generate sublibraries optimized for evaluating enrichment when virtually screening a dynamic ensemble of TAR determined by combining NMR spectroscopy data and molecular dynamics simulations. Ensemble-based virtual screening scores molecules with an area under the receiver operator characteristic curve of ~0.85-0.94 and with ~40-75% of all hits falling within the top 2% of scored molecules. The enrichment decreased significantly for ensembles generated from the same molecular dynamics simulations without input NMR data and for other control ensembles. The results demonstrate that experimentally determined RNA ensembles can significantly enrich libraries with true hits and that the degree of enrichment is dependent on the accuracy of the ensemble.
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Affiliation(s)
- Laura R Ganser
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, USA
| | - Janghyun Lee
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Atul Rangadurai
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, USA
| | | | - Megan L Kelly
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, USA
| | - Aman D Kansal
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, USA
| | | | - Hashim M Al-Hashimi
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, USA.
- Department of Chemistry, Duke University, Durham, NC, USA.
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53
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Bahramzadeh A, Jiang H, Huber T, Otting G. Two Histidines in an α‐Helix: A Rigid Co
2+
‐Binding Motif for PCS Measurements by NMR Spectroscopy. Angew Chem Int Ed Engl 2018; 57:6226-6229. [DOI: 10.1002/anie.201802501] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Indexed: 01/26/2023]
Affiliation(s)
- Alireza Bahramzadeh
- Research School of Chemistry The Australian National University Canberra ACT 2601 Australia
| | - Hailun Jiang
- Research School of Chemistry The Australian National University Canberra ACT 2601 Australia
| | - Thomas Huber
- Research School of Chemistry The Australian National University Canberra ACT 2601 Australia
| | - Gottfried Otting
- Research School of Chemistry The Australian National University Canberra ACT 2601 Australia
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54
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Kovalevskiy O, Nicholls RA, Long F, Carlon A, Murshudov GN. Overview of refinement procedures within REFMAC5: utilizing data from different sources. Acta Crystallogr D Struct Biol 2018; 74:215-227. [PMID: 29533229 PMCID: PMC5947762 DOI: 10.1107/s2059798318000979] [Citation(s) in RCA: 159] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 01/16/2018] [Indexed: 01/10/2023] Open
Abstract
Refinement is a process that involves bringing into agreement the structural model, available prior knowledge and experimental data. To achieve this, the refinement procedure optimizes a posterior conditional probability distribution of model parameters, including atomic coordinates, atomic displacement parameters (B factors), scale factors, parameters of the solvent model and twin fractions in the case of twinned crystals, given observed data such as observed amplitudes or intensities of structure factors. A library of chemical restraints is typically used to ensure consistency between the model and the prior knowledge of stereochemistry. If the observation-to-parameter ratio is small, for example when diffraction data only extend to low resolution, the Bayesian framework implemented in REFMAC5 uses external restraints to inject additional information extracted from structures of homologous proteins, prior knowledge about secondary-structure formation and even data obtained using different experimental methods, for example NMR. The refinement procedure also generates the `best' weighted electron-density maps, which are useful for further model (re)building. Here, the refinement of macromolecular structures using REFMAC5 and related tools distributed as part of the CCP4 suite is discussed.
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Affiliation(s)
- Oleg Kovalevskiy
- Structural Studies Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, England
| | - Robert A. Nicholls
- Structural Studies Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, England
| | - Fei Long
- Structural Studies Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, England
| | - Azzurra Carlon
- Magnetic Resonance Center (CERM), University of Florence and Interuniversity Consortium for Magnetic Resonance of Metalloproteins (CIRMMP), Via L. Sacconi 6, 50019 Sesto Fiorentino (FI), Italy
| | - Garib N. Murshudov
- Structural Studies Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, England
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55
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Abstract
NMR spectroscopy and other solution methods are increasingly being used to obtain novel insights into the mechanisms by which MAPK regulatory proteins bind and direct the activity of MAPKs. Here, we describe how interactions between the MAPK p38α and its regulatory proteins are studied using NMR spectroscopy, isothermal titration calorimetry, and small angle X-ray scattering (SAXS).
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Affiliation(s)
- Wolfgang Peti
- Department of Molecular Pharmacology, Physiology and Biotechnology, Brown University, Providence, RI, 02912, USA. .,Department of Chemistry, Brown University, Providence, RI, 02912, USA.
| | - Rebecca Page
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, 02912, USA
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56
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Lehner F, Kudlinzki D, Richter C, Müller-Werkmeister HM, Eberl KB, Bredenbeck J, Schwalbe H, Silvers R. Impact of Azidohomoalanine Incorporation on Protein Structure and Ligand Binding. Chembiochem 2017; 18:2340-2350. [DOI: 10.1002/cbic.201700437] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Florian Lehner
- Organic Chemistry and Chemical Biology; Goethe University Frankfurt; Max-von-Laue-Strasse 7 60438 Frankfurt am Main Germany
| | - Denis Kudlinzki
- Organic Chemistry and Chemical Biology; Goethe University Frankfurt; Max-von-Laue-Strasse 7 60438 Frankfurt am Main Germany
- German Cancer Consortium; DKTK; German Cancer Research Center; DKFZ; Im Neuenheimer Feld 280 69120 Heidelberg Germany
| | - Christian Richter
- Organic Chemistry and Chemical Biology; Goethe University Frankfurt; Max-von-Laue-Strasse 7 60438 Frankfurt am Main Germany
| | | | - Katharina B. Eberl
- Institute for Biophysics; Goethe University Frankfurt; Max-von-Laue-Strasse 1 60438 Frankfurt am Main Germany
| | - Jens Bredenbeck
- Institute for Biophysics; Goethe University Frankfurt; Max-von-Laue-Strasse 1 60438 Frankfurt am Main Germany
| | - Harald Schwalbe
- Organic Chemistry and Chemical Biology; Goethe University Frankfurt; Max-von-Laue-Strasse 7 60438 Frankfurt am Main Germany
| | - Robert Silvers
- Organic Chemistry and Chemical Biology; Goethe University Frankfurt; Max-von-Laue-Strasse 7 60438 Frankfurt am Main Germany
- Present address: Francis Bitter Magnet Laboratory; Massachusetts Institute of Technology; Cambridge MA 02139 USA
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57
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Milanowski DJ, Oku N, Cartner LK, Bokesch HR, Williamson RT, Saurí J, Liu Y, Blinov KA, Ding Y, Li XC, Ferreira D, Walker LA, Khan S, Davies-Coleman MT, Kelley JA, McMahon JB, Martin GE, Gustafson KR. Unequivocal determination of caulamidines A and B: application and validation of new tools in the structure elucidation tool box. Chem Sci 2017; 9:307-314. [PMID: 29619201 PMCID: PMC5868047 DOI: 10.1039/c7sc01996c] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 11/03/2017] [Indexed: 01/21/2023] Open
Abstract
Newly described NMR experimental approaches can provide valuable structural details and a complementary means of structure verification.
Ambiguities and errors in the structural assignment of organic molecules hinder both drug discovery and total synthesis efforts. Newly described NMR experimental approaches can provide valuable structural details and a complementary means of structure verification. The caulamidines are trihalogenated alkaloids from a marine bryozoan with an unprecedented structural scaffold. Their unique carbon and nitrogen framework was deduced by conventional NMR methods supplemented by new experiments that define 2-bond heteronuclear connectivities, reveal very long-range connectivity data, or visualize the 35,37Cl isotopic effect on chlorinated carbons. Computer-assisted structural elucidation (CASE) analysis of the spectroscopic data for caulamidine A provided only one viable structural alternative. Anisotropic NMR parameters, specifically residual dipolar coupling and residual chemical shift anisotropy data, were measured for caulamidine A and compared to DFT-calculated values for the proposed structure, the CASE-derived alternative structure, and two energetically feasible stereoisomers. Anisotropy-based NMR experiments provide a global, orthogonal means to verify complex structures free from investigator bias. The anisotropic NMR data were fully consistent with the assigned structure and configuration of caulamidine A. Caulamidine B has the same heterocyclic scaffold as A but a different composition and pattern of halogen substitution. Caulamidines A and B inhibited both wild-type and drug-resistant strains of the malaria parasite Plasmodium falciparum at low micromolar concentrations, yet were nontoxic to human cells.
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Affiliation(s)
- Dennis J Milanowski
- Molecular Targets Laboratory , Center for Cancer Research , National Cancer Institute , Frederick , Maryland 21702-1201 , USA .
| | - Naoya Oku
- Molecular Targets Laboratory , Center for Cancer Research , National Cancer Institute , Frederick , Maryland 21702-1201 , USA .
| | - Laura K Cartner
- Molecular Targets Laboratory , Center for Cancer Research , National Cancer Institute , Frederick , Maryland 21702-1201 , USA . .,Basic Science Program, Leidos Biomedical Research, Inc. , Frederick National Laboratory for Cancer Research , Frederick , Maryland 21702-1201 , USA
| | - Heidi R Bokesch
- Molecular Targets Laboratory , Center for Cancer Research , National Cancer Institute , Frederick , Maryland 21702-1201 , USA . .,Basic Science Program, Leidos Biomedical Research, Inc. , Frederick National Laboratory for Cancer Research , Frederick , Maryland 21702-1201 , USA
| | - R Thomas Williamson
- Structure Elucidation Group, Process and Analytical Research and Development , Merck & Co. Inc. , Rahway , New Jersey 07065 , USA .
| | - Josep Saurí
- Structure Elucidation Group, Process and Analytical Research and Development , Merck & Co. Inc. , Rahway , New Jersey 07065 , USA .
| | - Yizhou Liu
- Structure Elucidation Group, Process and Analytical Research and Development , Merck & Co. Inc. , Rahway , New Jersey 07065 , USA .
| | | | - Yuanqing Ding
- National Center for Natural Products Research , Department of BioMolecular Sciences , Division of Pharmacognosy , School of Pharmacy , University of Mississippi , Oxford , Mississippi 38655 , USA
| | - Xing-Cong Li
- National Center for Natural Products Research , Department of BioMolecular Sciences , Division of Pharmacognosy , School of Pharmacy , University of Mississippi , Oxford , Mississippi 38655 , USA
| | - Daneel Ferreira
- National Center for Natural Products Research , Department of BioMolecular Sciences , Division of Pharmacognosy , School of Pharmacy , University of Mississippi , Oxford , Mississippi 38655 , USA
| | - Larry A Walker
- National Center for Natural Products Research , Department of BioMolecular Sciences , Division of Pharmacognosy , School of Pharmacy , University of Mississippi , Oxford , Mississippi 38655 , USA
| | - Shabana Khan
- National Center for Natural Products Research , Department of BioMolecular Sciences , Division of Pharmacognosy , School of Pharmacy , University of Mississippi , Oxford , Mississippi 38655 , USA
| | | | - James A Kelley
- Chemical Biology Laboratory , Center for Cancer Research , National Cancer Institute , Frederick , Maryland 21702-1201 , USA
| | - James B McMahon
- Molecular Targets Laboratory , Center for Cancer Research , National Cancer Institute , Frederick , Maryland 21702-1201 , USA .
| | - Gary E Martin
- Structure Elucidation Group, Process and Analytical Research and Development , Merck & Co. Inc. , Rahway , New Jersey 07065 , USA .
| | - Kirk R Gustafson
- Molecular Targets Laboratory , Center for Cancer Research , National Cancer Institute , Frederick , Maryland 21702-1201 , USA .
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58
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Ravera E, Parigi G, Luchinat C. Perspectives on paramagnetic NMR from a life sciences infrastructure. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2017; 282:154-169. [PMID: 28844254 DOI: 10.1016/j.jmr.2017.07.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 07/28/2017] [Accepted: 07/31/2017] [Indexed: 05/17/2023]
Abstract
The effects arising in NMR spectroscopy because of the presence of unpaired electrons, collectively referred to as "paramagnetic NMR" have attracted increasing attention over the last decades. From the standpoint of the structural and mechanistic biology, paramagnetic NMR provides long range restraints that can be used to assess the accuracy of crystal structures in solution and to improve them by simultaneous refinements through NMR and X-ray data. These restraints also provide information on structure rearrangements and conformational variability in biomolecular systems. Theoretical improvements in quantum chemistry calculations can nowadays allow for accurate calculations of the paramagnetic data from a molecular structural model, thus providing a tool to refine the metal coordination environment by matching the paramagnetic effects observed far away from the metal. Furthermore, the availability of an improved technology (higher fields and faster magic angle spinning) has promoted paramagnetic NMR applications in the fast-growing area of biomolecular solid-state NMR. Major improvements in dynamic nuclear polarization have been recently achieved, especially through the exploitation of the Overhauser effect occurring through the contact-driven relaxation mechanism: the very large enhancement of the 13C signal observed in a variety of liquid organic compounds at high fields is expected to open up new perspectives for applications of solution NMR.
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Affiliation(s)
- Enrico Ravera
- Magnetic Resonance Center (CERM) and Department of Chemistry "Ugo Schiff", University of Florence, via Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Giacomo Parigi
- Magnetic Resonance Center (CERM) and Department of Chemistry "Ugo Schiff", University of Florence, via Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM) and Department of Chemistry "Ugo Schiff", University of Florence, via Sacconi 6, 50019 Sesto Fiorentino, Italy.
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59
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Cornilescu G, Ramos Alvarenga RF, Wyche TP, Bugni TS, Gil RR, Cornilescu CC, Westler WM, Markley JL, Schwieters CD. Progressive Stereo Locking (PSL): A Residual Dipolar Coupling Based Force Field Method for Determining the Relative Configuration of Natural Products and Other Small Molecules. ACS Chem Biol 2017; 12:2157-2163. [PMID: 28617580 DOI: 10.1021/acschembio.7b00281] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Establishing the relative configuration of a bioactive natural product represents the most challenging part in determining its structure. Residual dipolar couplings (RDCs) are sensitive probes of the relative spatial orientation of internuclear vectors. We adapted a force field structure calculation methodology to allow free sampling of both R and S configurations of the stereocenters of interest. The algorithm uses a floating alignment tensor in a simulated annealing protocol to identify the conformations and configurations that best fit experimental RDC and distance restraints (from NOE and J-coupling data). A unique configuration (for rigid molecules) or a very small number of configurations (for less rigid molecules) of the structural models having the lowest chiral angle energies and reasonable magnitudes of the alignment tensor are provided as the best predictions of the unknown configuration. For highly flexible molecules, the progressive locking of their stereocenters into their statistically dominant R or S state dramatically reduces the number of possible relative configurations. The result is verified by checking that the same configuration is obtained by initiating the locking from different regions of the molecule. For all molecules tested having known configurations (with conformations ranging from mostly rigid to highly flexible), the method accurately determined the correct configuration.
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Affiliation(s)
| | - René F. Ramos Alvarenga
- Pharmaceutical
Sciences Division, School of Pharmacy, University of Wisconsin—Madison, Madison, Wisconsin 53705, United States
| | - Thomas P. Wyche
- Pharmaceutical
Sciences Division, School of Pharmacy, University of Wisconsin—Madison, Madison, Wisconsin 53705, United States
- Biological
Chemistry and Molecular Pharmacology Department, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Tim S. Bugni
- Pharmaceutical
Sciences Division, School of Pharmacy, University of Wisconsin—Madison, Madison, Wisconsin 53705, United States
| | - Roberto R. Gil
- Department
of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | | | | | | | - Charles D. Schwieters
- Center for
Information Technology, National Institutes of Health, Bethesda, Maryland 20892-5624, United States
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60
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Khoo Y, Singer A, Cowburn D. Integrating NOE and RDC using sum-of-squares relaxation for protein structure determination. JOURNAL OF BIOMOLECULAR NMR 2017; 68:163-185. [PMID: 28616711 PMCID: PMC11347928 DOI: 10.1007/s10858-017-0108-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 03/31/2017] [Indexed: 06/07/2023]
Abstract
We revisit the problem of protein structure determination from geometrical restraints from NMR, using convex optimization. It is well-known that the NP-hard distance geometry problem of determining atomic positions from pairwise distance restraints can be relaxed into a convex semidefinite program (SDP). However, often the NOE distance restraints are too imprecise and sparse for accurate structure determination. Residual dipolar coupling (RDC) measurements provide additional geometric information on the angles between atom-pair directions and axes of the principal-axis-frame. The optimization problem involving RDC is highly non-convex and requires a good initialization even within the simulated annealing framework. In this paper, we model the protein backbone as an articulated structure composed of rigid units. Determining the rotation of each rigid unit gives the full protein structure. We propose solving the non-convex optimization problems using the sum-of-squares (SOS) hierarchy, a hierarchy of convex relaxations with increasing complexity and approximation power. Unlike classical global optimization approaches, SOS optimization returns a certificate of optimality if the global optimum is found. Based on the SOS method, we proposed two algorithms-RDC-SOS and RDC-NOE-SOS, that have polynomial time complexity in the number of amino-acid residues and run efficiently on a standard desktop. In many instances, the proposed methods exactly recover the solution to the original non-convex optimization problem. To the best of our knowledge this is the first time SOS relaxation is introduced to solve non-convex optimization problems in structural biology. We further introduce a statistical tool, the Cramér-Rao bound (CRB), to provide an information theoretic bound on the highest resolution one can hope to achieve when determining protein structure from noisy measurements using any unbiased estimator. Our simulation results show that when the RDC measurements are corrupted by Gaussian noise of realistic variance, both SOS based algorithms attain the CRB. We successfully apply our method in a divide-and-conquer fashion to determine the structure of ubiquitin from experimental NOE and RDC measurements obtained in two alignment media, achieving more accurate and faster reconstructions compared to the current state of the art.
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Affiliation(s)
- Y Khoo
- Department of Physics, Princeton University, Princeton, NJ, 08540, USA.
- Department of Mathematics, Stanford University, Stanford, CA, 94305, USA.
| | - A Singer
- Department of Mathematics and PACM, Princeton University, Princeton, NJ, 08544, USA
| | - D Cowburn
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
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61
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Structural basis for ligand binding to an enzyme by a conformational selection pathway. Proc Natl Acad Sci U S A 2017; 114:6298-6303. [PMID: 28559350 DOI: 10.1073/pnas.1700919114] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Proteins can bind target molecules through either induced fit or conformational selection pathways. In the conformational selection model, a protein samples a scarcely populated high-energy state that resembles a target-bound conformation. In enzymatic catalysis, such high-energy states have been identified as crucial entities for activity and the dynamic interconversion between ground states and high-energy states can constitute the rate-limiting step for catalytic turnover. The transient nature of these states has precluded direct observation of their properties. Here, we present a molecular description of a high-energy enzyme state in a conformational selection pathway by an experimental strategy centered on NMR spectroscopy, protein engineering, and X-ray crystallography. Through the introduction of a disulfide bond, we succeeded in arresting the enzyme adenylate kinase in a closed high-energy conformation that is on-pathway for catalysis. A 1.9-Å X-ray structure of the arrested enzyme in complex with a transition state analog shows that catalytic sidechains are properly aligned for catalysis. We discovered that the structural sampling of the substrate free enzyme corresponds to the complete amplitude that is associated with formation of the closed and catalytically active state. In addition, we found that the trapped high-energy state displayed improved ligand binding affinity, compared with the wild-type enzyme, demonstrating that substrate binding to the high-energy state is not occluded by steric hindrance. Finally, we show that quenching of fast time scale motions observed upon ligand binding to adenylate kinase is dominated by enzyme-substrate interactions and not by intramolecular interactions resulting from the conformational change.
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62
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Chiliveri SC, Deshmukh MV. Recent excitements in protein NMR: Large proteins and biologically relevant dynamics. J Biosci 2017; 41:787-803. [PMID: 27966496 DOI: 10.1007/s12038-016-9640-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The advent of Transverse Relaxation Optimized SpectroscopY (TROSY) and perdeuteration allowed biomolecular NMR spectroscopists to overcome the size limitation barrier (approx. 20 kDa) in de novo structure determination of proteins. The utility of these techniques was immediately demonstrated on large proteins and protein complexes (e.g. GroELGroES, ClpP protease, Hsp90-p53, 20S proteasome, etc.). Further, recent methodological developments such as Residual Dipolar Couplings and Paramagnetic Relaxation Enhancement allowed accurate measurement of long-range structural restraints. Additionally, Carr-Purcell-Meiboom-Gill (CPMG), rotating frame relaxation experiments (R1(rho)) and saturation transfer experiments (CEST and DEST) created never-before accessibility to the (mu)s-ms timescale dynamic parameters that led to the deeper understanding of biological processes. Meanwhile, the excitement in the field continued with a series of developments in the fast data acquisition methods allowing rapid structural studies on less stable proteins. This review aims to discuss important developments in the field of biomolecular NMR spectroscopy in the recent past, i.e., in the post TROSY era. These developments not only gave access to the structural studies of large protein assemblies, but also revolutionized tools in the arsenal of today's biomolecular NMR and point to a bright future of biomolecular NMR spectroscopy.
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63
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Nitsche C, Otting G. Pseudocontact shifts in biomolecular NMR using paramagnetic metal tags. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2017; 98-99:20-49. [PMID: 28283085 DOI: 10.1016/j.pnmrs.2016.11.001] [Citation(s) in RCA: 115] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 11/11/2016] [Accepted: 11/12/2016] [Indexed: 05/14/2023]
Affiliation(s)
- Christoph Nitsche
- Australian National University, Research School of Chemistry, Canberra, ACT 2601, Australia.
| | - Gottfried Otting
- Australian National University, Research School of Chemistry, Canberra, ACT 2601, Australia. http://www.rsc.anu.edu.au/~go/index.html
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64
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Yu F, Qiao J, Robblee J, Tsao D, Anderson J, Capila I. An Integrated Approach to Unique NMR Assignment of Methionine Methyl Resonances in Proteins. Anal Chem 2017; 89:1610-1616. [PMID: 28208280 DOI: 10.1021/acs.analchem.6b03705] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Fei Yu
- Momenta Pharmaceuticals Inc., 675 West Kendall Street, Cambridge, Massachusetts 02142, United States
| | - Jing Qiao
- Momenta Pharmaceuticals Inc., 675 West Kendall Street, Cambridge, Massachusetts 02142, United States
| | - John Robblee
- Momenta Pharmaceuticals Inc., 675 West Kendall Street, Cambridge, Massachusetts 02142, United States
| | - Desiree Tsao
- Momenta Pharmaceuticals Inc., 675 West Kendall Street, Cambridge, Massachusetts 02142, United States
| | - James Anderson
- Momenta Pharmaceuticals Inc., 675 West Kendall Street, Cambridge, Massachusetts 02142, United States
| | - Ishan Capila
- Momenta Pharmaceuticals Inc., 675 West Kendall Street, Cambridge, Massachusetts 02142, United States
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65
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Min J, Shih WM, Bellot G. Designing DNA Nanotube Liquid Crystals as a Weak-Alignment Medium for NMR Structure Determination of Membrane Proteins. Methods Mol Biol 2017; 1500:203-215. [PMID: 27813010 DOI: 10.1007/978-1-4939-6454-3_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Thirty percent of the human proteome is composed of membrane proteins that can perform a wide range of cellular functions and communications. They represent the core of modern medicine as the targets of about 50 % of all prescription pharmaceuticals. However, elucidating the structure of membrane proteins has represented a constant challenge, even in the modern era. To date, only a few hundred high-resolution structural models of membrane proteins are available. This chapter describes the emergence of DNA nanotechnology as a powerful tool for the structural characterization of membrane protein using solution-state nuclear magnetic resonance (NMR) spectroscopy. Here, we detail the large-scale synthesis of detergent-resistant DNA nanotubes that can be assembled into a dilute liquid crystal to be used as a weak-alignment media in solution NMR structure determination of membrane proteins.
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Affiliation(s)
- John Min
- Department of Genetics, Harvard Medical School, Boston, MA, 02115, USA
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, 02115, USA
- Sculpting Evolution Group, Media Lab, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - William M Shih
- Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, 02115, USA
- Department of Cancer Biology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, 02115, USA
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, 02115, USA
| | - Gaëtan Bellot
- Institut de Génomique Fonctionnelle, Centre National de la Recherche Scientifique, CNRS Unité Mixte de Recherche UMR 5203, Institut National de la Santé et de la Recherche Médicale, INSERM U1191, Montpellier, 34000, France.
- Université de Montpellier, Montpellier, 34000, France.
- Institut de Génomique Fonctionnelle, 141 rue de la Cardonille, Montpellier, Cedex 5, 34094, France.
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66
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Schmidts V. Perspectives in the application of residual dipolar couplings in the structure elucidation of weakly aligned small molecules. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2017; 55:54-60. [PMID: 27743456 DOI: 10.1002/mrc.4543] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 10/10/2016] [Accepted: 10/13/2016] [Indexed: 05/28/2023]
Abstract
This perspective article aims to review the general methodology in the application of residual dipolar couplings (RDCs) in the structure elucidation of small molecules and give the author's view on challenges for future applications. Recent improvements in the availability of alignment media, new pulse sequences for the measurement of couplings and improvements in the analysis software have garnered widespread interest in the technique. However, further generalization is needed in order to make RDC analysis into a truly "routine" method. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Volker Schmidts
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Darmstadt, Germany
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67
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Abstract
It is well-established that dynamics are central to protein function; their importance is implicitly acknowledged in the principles of the Monod, Wyman and Changeux model of binding cooperativity, which was originally proposed in 1965. Nowadays the concept of protein dynamics is formulated in terms of the energy landscape theory, which can be used to understand protein folding and conformational changes in proteins. Because protein dynamics are so important, a key to understanding protein function at the molecular level is to design experiments that allow their quantitative analysis. Nuclear magnetic resonance (NMR) spectroscopy is uniquely suited for this purpose because major advances in theory, hardware, and experimental methods have made it possible to characterize protein dynamics at an unprecedented level of detail. Unique features of NMR include the ability to quantify dynamics (i) under equilibrium conditions without external perturbations, (ii) using many probes simultaneously, and (iii) over large time intervals. Here we review NMR techniques for quantifying protein dynamics on fast (ps-ns), slow (μs-ms), and very slow (s-min) time scales. These techniques are discussed with reference to some major discoveries in protein science that have been made possible by NMR spectroscopy.
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68
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Kaltschnee L, Knoll K, Schmidts V, Adams RW, Nilsson M, Morris GA, Thiele CM. Extraction of distance restraints from pure shift NOE experiments. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2016; 271:99-109. [PMID: 27591956 DOI: 10.1016/j.jmr.2016.08.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 08/15/2016] [Accepted: 08/16/2016] [Indexed: 06/06/2023]
Abstract
NMR techniques incorporating pure shift methods to improve signal resolution have recently attracted much attention, owing to their potential use in studies of increasingly complex molecular systems. Extraction of frequencies from these simplified spectra enables easier structure determination, but only a few of the methods presented provide structural parameters derived from signal integral measurements. In particular, for quantification of the nuclear Overhauser effect (NOE) it is highly desirable to utilize pure shift techniques where signal overlap normally prevents accurate signal integration, to enable measurement of a larger number of interatomic distances. However, robust methods for the measurement of interatomic distances using the recently developed pure shift techniques have not been reported to date. In this work we discuss some of the factors determining the accuracy of measurements of signal integrals in interferogram-based Zangger-Sterk (ZS) pure shift NMR experiments. The ZS broadband homodecoupling technique is used in different experiments designed for quantitative NOE determination from pure shift spectra. It is shown that the techniques studied can be used for quantitative extraction of NOE-derived distance restraints, as exemplified for the test case of strychnine.
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Affiliation(s)
- Lukas Kaltschnee
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, D-64287 Darmstadt, Germany
| | - Kevin Knoll
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, D-64287 Darmstadt, Germany
| | - Volker Schmidts
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, D-64287 Darmstadt, Germany
| | - Ralph W Adams
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Mathias Nilsson
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Gareth A Morris
- School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Christina M Thiele
- Clemens-Schöpf-Institut für Organische Chemie und Biochemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 16, D-64287 Darmstadt, Germany.
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69
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Borkar AN, Bardaro MF, Camilloni C, Aprile FA, Varani G, Vendruscolo M. Structure of a low-population binding intermediate in protein-RNA recognition. Proc Natl Acad Sci U S A 2016; 113:7171-6. [PMID: 27286828 PMCID: PMC4932932 DOI: 10.1073/pnas.1521349113] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The interaction of the HIV-1 protein transactivator of transcription (Tat) and its cognate transactivation response element (TAR) RNA transactivates viral transcription and represents a paradigm for the widespread occurrence of conformational rearrangements in protein-RNA recognition. Although the structures of free and bound forms of TAR are well characterized, the conformations of the intermediates in the binding process are still unknown. By determining the free energy landscape of the complex using NMR residual dipolar couplings in replica-averaged metadynamics simulations, we observe two low-population intermediates. We then rationally design two mutants, one in the protein and another in the RNA, that weaken specific nonnative interactions that stabilize one of the intermediates. By using surface plasmon resonance, we show that these mutations lower the release rate of Tat, as predicted. These results identify the structure of an intermediate for RNA-protein binding and illustrate a general strategy to achieve this goal with high resolution.
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Affiliation(s)
- Aditi N Borkar
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Michael F Bardaro
- Department of Chemistry, University of Washington, Seattle, WA 98197-1700
| | - Carlo Camilloni
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Francesco A Aprile
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Gabriele Varani
- Department of Chemistry, University of Washington, Seattle, WA 98197-1700
| | - Michele Vendruscolo
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom;
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70
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Björling A, Niebling S, Marcellini M, van der Spoel D, Westenhoff S. Deciphering solution scattering data with experimentally guided molecular dynamics simulations. J Chem Theory Comput 2016; 11:780-7. [PMID: 25688181 PMCID: PMC4325560 DOI: 10.1021/ct5009735] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Indexed: 01/26/2023]
Abstract
![]()
Time-resolved
X-ray solution scattering is an increasingly popular
method to measure conformational changes in proteins. Extracting structural
information from the resulting difference X-ray scattering data is
a daunting task. We present a method in which the limited but precious
information encoded in such scattering curves is combined with the
chemical knowledge of molecular force fields. The molecule of interest
is then refined toward experimental data using molecular dynamics
simulation. Therefore, the energy landscape is biased toward conformations
that agree with experimental data. We describe and verify the method,
and we provide an implementation in GROMACS.
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Affiliation(s)
- Alexander Björling
- Department of Chemistry and Molecular Biology, University of Gothenburg, SE-405 30 Gothenburg, Sweden
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71
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Abstract
Allostery is a ubiquitous biological regulatory process in which distant binding sites within a protein or enzyme are functionally and thermodynamically coupled. Allosteric interactions play essential roles in many enzymological mechanisms, often facilitating formation of enzyme-substrate complexes and/or product release. Thus, elucidating the forces that drive allostery is critical to understanding the complex transformations of biomolecules. Currently, a number of models exist to describe allosteric behavior, taking into account energetics as well as conformational rearrangements and fluctuations. In the following Review, we discuss the use of solution NMR techniques designed to probe allosteric mechanisms in enzymes. NMR spectroscopy is unequaled in its ability to detect structural and dynamical changes in biomolecules, and the case studies presented herein demonstrate the range of insights to be gained from this valuable method. We also provide a detailed technical discussion of several specialized NMR experiments that are ideally suited for the study of enzymatic allostery.
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Affiliation(s)
- George P. Lisi
- Department of Chemistry, Yale University, New Haven, CT 06520
| | - J. Patrick Loria
- Department of Chemistry, Yale University, New Haven, CT 06520
- Department of Molecular Biophysics & Biochemistry, Yale University, New Haven, CT 06520
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72
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Venditti V, Egner TK, Clore GM. Hybrid Approaches to Structural Characterization of Conformational Ensembles of Complex Macromolecular Systems Combining NMR Residual Dipolar Couplings and Solution X-ray Scattering. Chem Rev 2016; 116:6305-22. [PMID: 26739383 PMCID: PMC5590664 DOI: 10.1021/acs.chemrev.5b00592] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Solving structures or structural ensembles of large macromolecular systems in solution poses a challenging problem. While NMR provides structural information at atomic resolution, increased spectral complexity, chemical shift overlap, and short transverse relaxation times (associated with slow tumbling) render application of the usual techniques that have been so successful for medium sized systems (<50 kDa) difficult. Solution X-ray scattering, on the other hand, is not limited by molecular weight but only provides low resolution structural information related to the overall shape and size of the system under investigation. Here we review how combining atomic resolution structures of smaller domains with sparse experimental data afforded by NMR residual dipolar couplings (which yield both orientational and shape information) and solution X-ray scattering data in rigid-body simulated annealing calculations provides a powerful approach for investigating the structural aspects of conformational dynamics in large multidomain proteins. The application of this hybrid methodology is illustrated for the 128 kDa dimer of bacterial Enzyme I which exists in a variety of open and closed states that are sampled at various points in the catalytic cycles, and for the capsid protein of the human immunodeficiency virus.
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Affiliation(s)
- Vincenzo Venditti
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa 50011, United States
| | - Timothy K. Egner
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, United States
| | - G. Marius Clore
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0520, United States
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73
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Hansen MR, Hanson P, Pardi A. Pf1 filamentous phage as an alignment tool for generating local and global structural information in nucleic acids. J Biomol Struct Dyn 2016; 17 Suppl 1:365-9. [PMID: 22607445 DOI: 10.1080/07391102.2000.10506642] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Abstract Pf1 filamentous phage represent a simple versatile method for generating partially ordered macromolecules in solution. The phage allow tunable degrees of alignment of macromolecules under a wide range of temperature and solvent conditions. The negatively charged phage are ideal for aligning negatively charged nucleic acids and these phage-nucleic acid solutions are stable indefinitely. We have used Pf1 phage to align various DNA and RNA molecules in solution for measurement of dipolar coupling interactions. These dipolar couplings can be used to improve the local structure of nucleic acids. More importantly they also contain information on the global structure, such as DNA bending, which presently cannot be obtained by standard NMR methods. The principles involved in using Pf1 phage to generate solutions of partially order macromolecules will be discussed. The use of (1)H-(1)H, (1)H-(13)C and (1)H-(15)N dipolar couplings for generating angle constraints for structure refinement of nucleic acids will also be discussed.
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Affiliation(s)
- M R Hansen
- a Department of Chemistry and Biochemistry , University of Colorado at Boulder , Boulder , CO , 80309-0215
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74
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Shi X, Rienstra CM. Site-Specific Internal Motions in GB1 Protein Microcrystals Revealed by 3D ²H-¹³C-¹³C Solid-State NMR Spectroscopy. J Am Chem Soc 2016; 138:4105-19. [PMID: 26849428 PMCID: PMC4819898 DOI: 10.1021/jacs.5b12974] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Indexed: 02/04/2023]
Abstract
(2)H quadrupolar line shapes deliver rich information about protein dynamics. A newly designed 3D (2)H-(13)C-(13)C solid-state NMR magic angle spinning (MAS) experiment is presented and demonstrated on the microcrystalline β1 immunoglobulin binding domain of protein G (GB1). The implementation of (2)H-(13)C adiabatic rotor-echo-short-pulse-irradiation cross-polarization (RESPIRATION CP) ensures the accuracy of the extracted line shapes and provides enhanced sensitivity relative to conventional CP methods. The 3D (2)H-(13)C-(13)C spectrum reveals (2)H line shapes for 140 resolved aliphatic deuterium sites. Motional-averaged (2)H quadrupolar parameters obtained from the line-shape fitting identify side-chain motions. Restricted side-chain dynamics are observed for a number of polar residues including K13, D22, E27, K31, D36, N37, D46, D47, K50, and E56, which we attribute to the effects of salt bridges and hydrogen bonds. In contrast, we observe significantly enhanced side-chain flexibility for Q2, K4, K10, E15, E19, N35, N40, and E42, due to solvent exposure and low packing density. T11, T16, and T17 side chains exhibit motions with larger amplitudes than other Thr residues due to solvent interactions. The side chains of L5, V54, and V29 are highly rigid because they are packed in the core of the protein. High correlations were demonstrated between GB1 side-chain dynamics and its biological function. Large-amplitude side-chain motions are observed for regions contacting and interacting with immunoglobulin G (IgG). In contrast, rigid side chains are primarily found for residues in the structural core of the protein that are absent from protein binding and interactions.
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Affiliation(s)
- Xiangyan Shi
- Department of Chemistry, University of Illinois at Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States
| | - Chad M. Rienstra
- Department of Chemistry, University of Illinois at Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States
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75
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Carlon A, Ravera E, Andrałojć W, Parigi G, Murshudov GN, Luchinat C. How to tackle protein structural data from solution and solid state: An integrated approach. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2016; 92-93:54-70. [PMID: 26952192 DOI: 10.1016/j.pnmrs.2016.01.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 01/13/2016] [Accepted: 01/13/2016] [Indexed: 05/17/2023]
Abstract
Long-range NMR restraints, such as diamagnetic residual dipolar couplings and paramagnetic data, can be used to determine 3D structures of macromolecules. They are also used to monitor, and potentially to improve, the accuracy of a macromolecular structure in solution by validating or "correcting" a crystal model. Since crystal structures suffer from crystal packing forces they may not be accurate models for the macromolecular structures in solution. However, the presence of real differences should be tested for by simultaneous refinement of the structure using both crystal and solution NMR data. To achieve this, the program REFMAC5 from CCP4 was modified to allow the simultaneous use of X-ray crystallographic and paramagnetic NMR data and/or diamagnetic residual dipolar couplings. Inconsistencies between crystal structures and solution NMR data, if any, may be due either to structural rearrangements occurring on passing from the solution to solid state, or to a greater degree of conformational heterogeneity in solution with respect to the crystal. In the case of multidomain proteins, paramagnetic restraints can provide the correct mutual orientations and positions of domains in solution, as well as information on the conformational variability experienced by the macromolecule.
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Affiliation(s)
- Azzurra Carlon
- Magnetic Resonance Center (CERM) and Department of Chemistry "Ugo Schiff", University of Florence, Italy(1).
| | - Enrico Ravera
- Magnetic Resonance Center (CERM) and Department of Chemistry "Ugo Schiff", University of Florence, Italy(1).
| | - Witold Andrałojć
- Magnetic Resonance Center (CERM) and Department of Chemistry "Ugo Schiff", University of Florence, Italy(1).
| | - Giacomo Parigi
- Magnetic Resonance Center (CERM) and Department of Chemistry "Ugo Schiff", University of Florence, Italy(1).
| | - Garib N Murshudov
- MRC Laboratory for Molecular Biology, Francis Crick Ave, Cambridge CB2 0QH, UK.
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM) and Department of Chemistry "Ugo Schiff", University of Florence, Italy(1).
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76
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Barb AW, Subedi GP. An encodable lanthanide binding tag with reduced size and flexibility for measuring residual dipolar couplings and pseudocontact shifts in large proteins. JOURNAL OF BIOMOLECULAR NMR 2016; 64:75-85. [PMID: 26728077 PMCID: PMC4884023 DOI: 10.1007/s10858-015-0009-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 12/28/2015] [Indexed: 05/03/2023]
Abstract
Metal ions serve important roles in structural biology applications from long-range perturbations seen in magnetic resonance experiments to electron-dense signatures in X-ray crystallography data; however, the metal ion must be secured in a molecular framework to achieve the maximum benefit. Polypeptide-based lanthanide-binding tags (LBTs) represent one option that can be directly encoded within a recombinant protein expression construct. However, LBTs often exhibit significant mobility relative to the target molecule. Here we report the characterization of improved LBTs sequences for insertion into a protein loop. These LBTs were inserted to connect two parallel alpha helices of an immunoglobulin G (IgG)-binding Z domain platform. Variants A and B bound Tb(3+) with high affinity (0.70 and 0.13 μM, respectively) and displayed restricted LBT motion. Compared to the parent construct, the metal-bound A experienced a 2.5-fold reduction in tag motion as measured by magnetic field-induced residual dipolar couplings and was further studied in a 72.2 kDa complex with the human IgG1 fragment crystallizable (IgG1 Fc) glycoprotein. The appearance of both pseudo-contact shifts (-0.221 to 0.081 ppm) and residual dipolar couplings (-7.6 to 14.3 Hz) of IgG1 Fc resonances in the IgG1 Fc:(variant A:Tb(3+))2 complex indicated structural restriction of the LBT with respect to the Fc. These studies highlight the applicability of improved LBT sequences with reduced mobility to probe the structure of macromolecular systems.
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Affiliation(s)
- Adam W Barb
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, 2214 Molecular Biology Building, Ames, IA, 50011, USA.
| | - Ganesh P Subedi
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, 2214 Molecular Biology Building, Ames, IA, 50011, USA
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77
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Chen JL, Yang Y, Zhang LL, Liang H, Huber T, Su XC, Otting G. Analysis of the solution conformations of T4 lysozyme by paramagnetic NMR spectroscopy. Phys Chem Chem Phys 2016; 18:5850-9. [DOI: 10.1039/c5cp07196h] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Paramagnetic data show that the average structure of T4-lysozyme in solution is more open than its crystal structure.
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Affiliation(s)
- Jia-Liang Chen
- State Key Laboratory of Elemento-organic Chemistry
- The Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)
- Nankai University
- Tianjin 300071
- China
| | - Yin Yang
- State Key Laboratory of Elemento-organic Chemistry
- The Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)
- Nankai University
- Tianjin 300071
- China
| | - Lin-Lin Zhang
- State Key Laboratory of Elemento-organic Chemistry
- The Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)
- Nankai University
- Tianjin 300071
- China
| | - Haobo Liang
- Research School of Chemistry
- Australian National University
- Canberra
- Australia
| | - Thomas Huber
- Research School of Chemistry
- Australian National University
- Canberra
- Australia
| | - Xun-Cheng Su
- State Key Laboratory of Elemento-organic Chemistry
- The Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)
- Nankai University
- Tianjin 300071
- China
| | - Gottfried Otting
- Research School of Chemistry
- Australian National University
- Canberra
- Australia
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78
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Camilloni C, Vendruscolo M. Using Pseudocontact Shifts and Residual Dipolar Couplings as Exact NMR Restraints for the Determination of Protein Structural Ensembles. Biochemistry 2015; 54:7470-6. [DOI: 10.1021/acs.biochem.5b01138] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Carlo Camilloni
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Michele Vendruscolo
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
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79
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Salmon L, Blackledge M. Investigating protein conformational energy landscapes and atomic resolution dynamics from NMR dipolar couplings: a review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2015; 78:126601. [PMID: 26517337 DOI: 10.1088/0034-4885/78/12/126601] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Nuclear magnetic resonance spectroscopy is exquisitely sensitive to protein dynamics. In particular inter-nuclear dipolar couplings, that become measurable in solution when the protein is dissolved in a dilute liquid crystalline solution, report on all conformations sampled up to millisecond timescales. As such they provide the opportunity to describe the Boltzmann distribution present in solution at atomic resolution, and thereby to map the conformational energy landscape in unprecedented detail. The development of analytical methods and approaches based on numerical simulation and their application to numerous biologically important systems is presented.
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Affiliation(s)
- Loïc Salmon
- Université Grenoble Alpes, Institut de Biologie Structurale (IBS), F-38027 Grenoble, France. CEA, DSV, IBS, F-38027 Grenoble, France. CNRS, IBS, F-38027 Grenoble, France
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80
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Takeuchi K, Arthanari H, Shimada I, Wagner G. Nitrogen detected TROSY at high field yields high resolution and sensitivity for protein NMR. JOURNAL OF BIOMOLECULAR NMR 2015; 63:323-331. [PMID: 26497830 PMCID: PMC4749451 DOI: 10.1007/s10858-015-9991-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2015] [Accepted: 10/01/2015] [Indexed: 05/18/2023]
Abstract
Detection of (15)N in multidimensional NMR experiments of proteins has sparsely been utilized because of the low gyromagnetic ratio (γ) of nitrogen and the presumed low sensitivity of such experiments. Here we show that selecting the TROSY components of proton-attached (15)N nuclei (TROSY (15)NH) yields high quality spectra in high field magnets (>600 MHz) by taking advantage of the slow (15)N transverse relaxation and compensating for the inherently low (15)N sensitivity. The (15)N TROSY transverse relaxation rates increase modestly with molecular weight but the TROSY gain in peak heights depends strongly on the magnetic field strength. Theoretical simulations predict that the narrowest line width for the TROSY (15)NH component can be obtained at 900 MHz, but sensitivity reaches its maximum around 1.2 GHz. Based on these considerations, a (15)N-detected 2D (1)H-(15)N TROSY-HSQC ((15)N-detected TROSY-HSQC) experiment was developed and high-quality 2D spectra were recorded at 800 MHz in 2 h for 1 mM maltose-binding protein at 278 K (τc ~ 40 ns). Unlike for (1)H detected TROSY, deuteration is not mandatory to benefit (15)N detected TROSY due to reduced dipolar broadening, which facilitates studies of proteins that cannot be deuterated, especially in cases where production requires eukaryotic expression systems. The option of recording (15)N TROSY of proteins expressed in H2O media also alleviates the problem of incomplete amide proton back exchange, which often hampers the detection of amide groups in the core of large molecular weight proteins that are expressed in D2O culture media and cannot be refolded for amide back exchange. These results illustrate the potential of (15)NH-detected TROSY experiments as a means to exploit the high resolution offered by high field magnets near and above 1 GHz.
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Affiliation(s)
- Koh Takeuchi
- Molecular Profiling Research Center for Drug Discovery, National Institute for Advanced Industrial Science and Technology, Tokyo, 135-0063, Japan
- PRESTO, JST, Tokyo, 135-0063, Japan
| | - Haribabu Arthanari
- Department of Biochemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, MA, 02115, USA
| | - Ichio Shimada
- Molecular Profiling Research Center for Drug Discovery, National Institute for Advanced Industrial Science and Technology, Tokyo, 135-0063, Japan.
- Graduate Schools of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
| | - Gerhard Wagner
- Department of Biochemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, MA, 02115, USA.
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81
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Vammi V, Song G. Ensembles of a small number of conformations with relative populations. JOURNAL OF BIOMOLECULAR NMR 2015; 63:341-351. [PMID: 26474790 DOI: 10.1007/s10858-015-9993-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 10/14/2015] [Indexed: 06/05/2023]
Abstract
In our previous work, we proposed a new way to represent protein native states, using ensembles of a small number of conformations with relative Populations, or ESP in short. Using Ubiquitin as an example, we showed that using a small number of conformations could greatly reduce the potential of overfitting and assigning relative populations to protein ensembles could significantly improve their quality. To demonstrate that ESP indeed is an excellent alternative to represent protein native states, in this work we compare the quality of two ESP ensembles of Ubiquitin with several well-known regular ensembles or average structure representations. Extensive amount of significant experimental data are employed to achieve a thorough assessment. Our results demonstrate that ESP ensembles, though much smaller in size comparing to regular ensembles, perform equally or even better sometimes in all four different types of experimental data used in the assessment, namely, the residual dipolar couplings, residual chemical shift anisotropy, hydrogen exchange rates, and solution scattering profiles. This work further underlines the significance of having relative populations in describing the native states.
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Affiliation(s)
- Vijay Vammi
- Bioinformatics and Computational Biology Program, Department of Computer Science, Iowa State University, 226 Atanasoff Hall, Ames, IA, 50011, USA.
| | - Guang Song
- Bioinformatics and Computational Biology Program, Department of Computer Science, Iowa State University, 226 Atanasoff Hall, Ames, IA, 50011, USA
- Baker Center for Bioinformatics and Biological Statistics, Iowa State University, Ames, IA, USA
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82
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Ren A, Xue Y, Peselis A, Serganov A, Al-Hashimi HM, Patel DJ. Structural and Dynamic Basis for Low-Affinity, High-Selectivity Binding of L-Glutamine by the Glutamine Riboswitch. Cell Rep 2015; 13:1800-13. [PMID: 26655897 DOI: 10.1016/j.celrep.2015.10.062] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 08/17/2015] [Accepted: 10/20/2015] [Indexed: 12/24/2022] Open
Abstract
Naturally occurring L-glutamine riboswitches occur in cyanobacteria and marine metagenomes, where they reside upstream of genes involved in nitrogen metabolism. By combining X-ray, NMR, and MD, we characterized an L-glutamine-dependent conformational transition in the Synechococcus elongatus glutamine riboswitch from tuning fork to L-shaped alignment of stem segments. This transition generates an open ligand-binding pocket with L-glutamine selectivity enforced by Mg(2+)-mediated intermolecular interactions. The transition also stabilizes the P1 helix through a long-range "linchpin" Watson-Crick G-C pair-capping interaction, while melting a short helix below P1 potentially capable of modulating downstream readout. NMR data establish that the ligand-free glutamine riboswitch in Mg(2+) solution exists in a slow equilibrium between flexible tuning fork and a minor conformation, similar, but not identical, to the L-shaped bound conformation. We propose that an open ligand-binding pocket combined with a high conformational penalty for forming the ligand-bound state provide mechanisms for reducing binding affinity while retaining high selectivity.
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Affiliation(s)
- Aiming Ren
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA
| | - Yi Xue
- Department of Biochemistry and Chemistry, Duke University Medical Center, Durham, NC 27710, USA
| | - Alla Peselis
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10016, USA
| | - Alexander Serganov
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10016, USA
| | - Hashim M Al-Hashimi
- Department of Biochemistry and Chemistry, Duke University Medical Center, Durham, NC 27710, USA.
| | - Dinshaw J Patel
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA.
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83
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Newby FN, De Simone A, Yagi-Utsumi M, Salvatella X, Dobson CM, Vendruscolo M. Structure-Free Validation of Residual Dipolar Coupling and Paramagnetic Relaxation Enhancement Measurements of Disordered Proteins. Biochemistry 2015; 54:6876-86. [DOI: 10.1021/acs.biochem.5b00670] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Francisco N. Newby
- Department
of Chemistry, University of Cambridge, Cambridge CB2 1EW, U.K
| | - Alfonso De Simone
- Department
of Life Sciences, Imperial College London, South Kensington, London SW7 2AZ, U.K
| | - Maho Yagi-Utsumi
- Department
of Chemistry, University of Cambridge, Cambridge CB2 1EW, U.K
- Institute
for Integrative Bioscience, National Institutes of Natural Sciences, 5-1 Higashiyama Myodaiji, Okazaki 444-8787, Japan
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84
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Nowakowski M, Saxena S, Stanek J, Żerko S, Koźmiński W. Applications of high dimensionality experiments to biomolecular NMR. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2015; 90-91:49-73. [PMID: 26592945 DOI: 10.1016/j.pnmrs.2015.07.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 07/03/2015] [Accepted: 07/03/2015] [Indexed: 05/23/2023]
Abstract
High dimensionality NMR experiments facilitate resonance assignment and precise determination of spectral parameters such as coupling constants. Sparse non-uniform sampling enables acquisition of experiments of high dimensionality with high resolution in acceptable time. In this review we present and compare some significant applications of NMR experiments of dimensionality higher than three in the field of biomolecular studies in solution.
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Affiliation(s)
- Michał Nowakowski
- Biological and Chemical Research Centre, Faculty of Chemistry, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Saurabh Saxena
- Biological and Chemical Research Centre, Faculty of Chemistry, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Jan Stanek
- Biological and Chemical Research Centre, Faculty of Chemistry, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Szymon Żerko
- Biological and Chemical Research Centre, Faculty of Chemistry, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Wiktor Koźmiński
- Biological and Chemical Research Centre, Faculty of Chemistry, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland.
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85
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Zhao B, Zhang Q. Measuring Residual Dipolar Couplings in Excited Conformational States of Nucleic Acids by CEST NMR Spectroscopy. J Am Chem Soc 2015; 137:13480-3. [PMID: 26462068 DOI: 10.1021/jacs.5b09014] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Nucleic acids undergo structural transitions to access sparsely populated and transiently lived conformational states--or excited conformational states--that play important roles in diverse biological processes. Despite ever-increasing detection of these functionally essential states, 3D structure determination of excited states (ESs) of RNA remains elusive. This is largely due to challenges in obtaining high-resolution structural constraints in these ESs by conventional structural biology approaches. Here, we present nucleic-acid-optimized chemical exchange saturation transfer (CEST) NMR spectroscopy for measuring residual dipolar couplings (RDCs), which provide unique long-range angular constraints in ESs of nucleic acids. We demonstrate these approaches on a fluoride riboswitch, where one-bond (13)C-(1)H RDCs from both base and sugar moieties provide direct structural probes into an ES of the ligand-free riboswitch.
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Affiliation(s)
- Bo Zhao
- Department of Biochemistry and Biophysics and ‡Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States
| | - Qi Zhang
- Department of Biochemistry and Biophysics and ‡Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599, United States
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86
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Salmon L, Giambaşu GM, Nikolova EN, Petzold K, Bhattacharya A, Case DA, Al-Hashimi HM. Modulating RNA Alignment Using Directional Dynamic Kinks: Application in Determining an Atomic-Resolution Ensemble for a Hairpin using NMR Residual Dipolar Couplings. J Am Chem Soc 2015; 137:12954-65. [PMID: 26306428 PMCID: PMC4748170 DOI: 10.1021/jacs.5b07229] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Approaches that combine experimental data and computational molecular dynamics (MD) to determine atomic resolution ensembles of biomolecules require the measurement of abundant experimental data. NMR residual dipolar couplings (RDCs) carry rich dynamics information, however, difficulties in modulating overall alignment of nucleic acids have limited the ability to fully extract this information. We present a strategy for modulating RNA alignment that is based on introducing variable dynamic kinks in terminal helices. With this strategy, we measured seven sets of RDCs in a cUUCGg apical loop and used this rich data set to test the accuracy of an 0.8 μs MD simulation computed using the Amber ff10 force field as well as to determine an atomic resolution ensemble. The MD-generated ensemble quantitatively reproduces the measured RDCs, but selection of a sub-ensemble was required to satisfy the RDCs within error. The largest discrepancies between the RDC-selected and MD-generated ensembles are observed for the most flexible loop residues and backbone angles connecting the loop to the helix, with the RDC-selected ensemble resulting in more uniform dynamics. Comparison of the RDC-selected ensemble with NMR spin relaxation data suggests that the dynamics occurs on the ps-ns time scales as verified by measurements of R(1ρ) relaxation-dispersion data. The RDC-satisfying ensemble samples many conformations adopted by the hairpin in crystal structures indicating that intrinsic plasticity may play important roles in conformational adaptation. The approach presented here can be applied to test nucleic acid force fields and to characterize dynamics in diverse RNA motifs at atomic resolution.
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Affiliation(s)
- Loïc Salmon
- Department of Molecular, Cellular, and Developmental Biology and Howard Hughes Medical Institute, University of Michigan, Ann Arbor, Michigan, USA
| | - George M. Giambaşu
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey, USA
| | - Evgenia N. Nikolova
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Katja Petzold
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden
| | | | - David A. Case
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey, USA
| | - Hashim M. Al-Hashimi
- Department of Biochemistry and Chemistry, Duke University School of Medicine, Durham, North Carolina, USA
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87
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Yang S, Al-Hashimi HM. Unveiling Inherent Degeneracies in Determining Population-Weighted Ensembles of Interdomain Orientational Distributions Using NMR Residual Dipolar Couplings: Application to RNA Helix Junction Helix Motifs. J Phys Chem B 2015; 119:9614-26. [PMID: 26131693 DOI: 10.1021/acs.jpcb.5b03859] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
A growing number of studies employ time-averaged experimental data to determine dynamic ensembles of biomolecules. While it is well-known that different ensembles can satisfy experimental data to within error, the extent and nature of these degeneracies, and their impact on the accuracy of the ensemble determination remains poorly understood. Here, we use simulations and a recently introduced metric for assessing ensemble similarity to explore degeneracies in determining ensembles using NMR residual dipolar couplings (RDCs) with specific application to A-form helices in RNA. Various target ensembles were constructed representing different domain-domain orientational distributions that are confined to a topologically restricted (<10%) conformational space. Five independent sets of ensemble averaged RDCs were then computed for each target ensemble and a "sample and select" scheme used to identify degenerate ensembles that satisfy RDCs to within experimental uncertainty. We find that ensembles with different ensemble sizes and that can differ significantly from the target ensemble (by as much as ∑Ω ∼ 0.4 where ∑Ω varies between 0 and 1 for maximum and minimum ensemble similarity, respectively) can satisfy the ensemble averaged RDCs. These deviations increase with the number of unique conformers and breadth of the target distribution, and result in significant uncertainty in determining conformational entropy (as large as 5 kcal/mol at T = 298 K). Nevertheless, the RDC-degenerate ensembles are biased toward populated regions of the target ensemble, and capture other essential features of the distribution, including the shape. Our results identify ensemble size as a major source of uncertainty in determining ensembles and suggest that NMR interactions such as RDCs and spin relaxation, on their own, do not carry the necessary information needed to determine conformational entropy at a useful level of precision. The framework introduced here provides a general approach for exploring degeneracies in ensemble determination for different types of experimental data.
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Affiliation(s)
- Shan Yang
- †Department of Biochemistry, Stanford University School of Medicine, 279 Campus Drive, Stanford, California 94305, United States
| | - Hashim M Al-Hashimi
- ‡Department of Biochemistry and Chemistry, Duke University Medical Center, Durham, North Carolina 27705, United States
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88
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Andrałojć W, Berlin K, Fushman D, Luchinat C, Parigi G, Ravera E, Sgheri L. Information content of long-range NMR data for the characterization of conformational heterogeneity. JOURNAL OF BIOMOLECULAR NMR 2015; 62:353-71. [PMID: 26044033 PMCID: PMC4782772 DOI: 10.1007/s10858-015-9951-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 05/25/2015] [Indexed: 05/16/2023]
Abstract
Long-range NMR data, namely residual dipolar couplings (RDCs) from external alignment and paramagnetic data, are becoming increasingly popular for the characterization of conformational heterogeneity of multidomain biomacromolecules and protein complexes. The question addressed here is how much information is contained in these averaged data. We have analyzed and compared the information content of conformationally averaged RDCs caused by steric alignment and of both RDCs and pseudocontact shifts caused by paramagnetic alignment, and found that, despite the substantial differences, they contain a similar amount of information. Furthermore, using several synthetic tests we find that both sets of data are equally good towards recovering the major state(s) in conformational distributions.
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Affiliation(s)
- Witold Andrałojć
- Center for Magnetic Resonance (CERM), University of Florence, Via
L. Sacconi 6, 50019, Sesto Fiorentino, Italy
| | - Konstantin Berlin
- Department of Chemistry and Biochemistry, Center for Biomolecular
Structure and Organization, University of Maryland, College Park, MD 20742, USA
| | - David Fushman
- Department of Chemistry and Biochemistry, Center for Biomolecular
Structure and Organization, University of Maryland, College Park, MD 20742, USA
- Corresponding authors: David Fushman, ,
Claudio Luchinat,
| | - Claudio Luchinat
- Center for Magnetic Resonance (CERM), University of Florence, Via
L. Sacconi 6, 50019, Sesto Fiorentino, Italy
- Department of Chemistry "Ugo Schiff", University
of Florence, Via della Lastruccia 3, 50019, Sesto Fiorentino, Italy
- Corresponding authors: David Fushman, ,
Claudio Luchinat,
| | - Giacomo Parigi
- Center for Magnetic Resonance (CERM), University of Florence, Via
L. Sacconi 6, 50019, Sesto Fiorentino, Italy
- Department of Chemistry "Ugo Schiff", University
of Florence, Via della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | - Enrico Ravera
- Center for Magnetic Resonance (CERM), University of Florence, Via
L. Sacconi 6, 50019, Sesto Fiorentino, Italy
- Department of Chemistry "Ugo Schiff", University
of Florence, Via della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | - Luca Sgheri
- Istituto per le Applicazioni del Calcolo, Sezione di Firenze,
CNR, Via Madonna del Piano 10, 50019 Sesto Fiorentino, Italy
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89
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Olsson S, Ekonomiuk D, Sgrignani J, Cavalli A. Molecular Dynamics of Biomolecules through Direct Analysis of Dipolar Couplings. J Am Chem Soc 2015; 137:6270-8. [PMID: 25895902 DOI: 10.1021/jacs.5b01289] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Residual dipolar couplings (RDCs) are important probes in structural biology, but their analysis is often complicated by the determination of an alignment tensor or its associated assumptions. We here apply the maximum entropy principle to derive a tensor-free formalism which allows for direct, dynamic analysis of RDCs and holds the classic tensor formalism as a special case. Specifically, the framework enables us to robustly analyze data regardless of whether a clear separation of internal and overall dynamics is possible. Such a separation is often difficult in the core subjects of current structural biology, which include multidomain and intrinsically disordered proteins as well as nucleic acids. We demonstrate the method is tractable and self-consistent and generalizes to data sets comprised of observations from multiple different alignment conditions.
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Affiliation(s)
- Simon Olsson
- †Institute for Research in Biomedicine, Via Vincenzo Vela 6, CH-6500 Bellinzona, Switzerland.,‡Laboratory of Physical Chemistry, Eidgenössische Technische Hochschule Zürich, Vladimir-Prelog-Weg 2, 8093 Zürich, Switzerland
| | - Dariusz Ekonomiuk
- †Institute for Research in Biomedicine, Via Vincenzo Vela 6, CH-6500 Bellinzona, Switzerland
| | - Jacopo Sgrignani
- †Institute for Research in Biomedicine, Via Vincenzo Vela 6, CH-6500 Bellinzona, Switzerland
| | - Andrea Cavalli
- †Institute for Research in Biomedicine, Via Vincenzo Vela 6, CH-6500 Bellinzona, Switzerland.,§Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW United Kingdom
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90
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Park SH, Wang V, Radoicic J, De Angelis AA, Berkamp S, Opella SJ. Paramagnetic relaxation enhancement of membrane proteins by incorporation of the metal-chelating unnatural amino acid 2-amino-3-(8-hydroxyquinolin-3-yl)propanoic acid (HQA). JOURNAL OF BIOMOLECULAR NMR 2015; 61:185-96. [PMID: 25430059 PMCID: PMC4398598 DOI: 10.1007/s10858-014-9884-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 11/20/2014] [Indexed: 05/16/2023]
Abstract
The use of paramagnetic constraints in protein NMR is an active area of research because of the benefits of long-range distance measurements (>10 Å). One of the main issues in successful execution is the incorporation of a paramagnetic metal ion into diamagnetic proteins. The most common metal ion tags are relatively long aliphatic chains attached to the side chain of a selected cysteine residue with a chelating group at the end where it can undergo substantial internal motions, decreasing the accuracy of the method. An attractive alternative approach is to incorporate an unnatural amino acid that binds metal ions at a specific site on the protein using the methods of molecular biology. Here we describe the successful incorporation of the unnatural amino acid 2-amino-3-(8-hydroxyquinolin-3-yl)propanoic acid (HQA) into two different membrane proteins by heterologous expression in E. coli. Fluorescence and NMR experiments demonstrate complete replacement of the natural amino acid with HQA and stable metal chelation by the mutated proteins. Evidence of site-specific intra- and inter-molecular PREs by NMR in micelle solutions sets the stage for the use of HQA incorporation in solid-state NMR structure determinations of membrane proteins in phospholipid bilayers.
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91
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Crick DJ, Wang JX, Graham B, Swarbrick JD, Mott HR, Nietlispach D. Integral membrane protein structure determination using pseudocontact shifts. JOURNAL OF BIOMOLECULAR NMR 2015; 61:197-207. [PMID: 25604936 PMCID: PMC4412549 DOI: 10.1007/s10858-015-9899-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 01/13/2015] [Indexed: 05/16/2023]
Abstract
Obtaining enough experimental restraints can be a limiting factor in the NMR structure determination of larger proteins. This is particularly the case for large assemblies such as membrane proteins that have been solubilized in a membrane-mimicking environment. Whilst in such cases extensive deuteration strategies are regularly utilised with the aim to improve the spectral quality, these schemes often limit the number of NOEs obtainable, making complementary strategies highly beneficial for successful structure elucidation. Recently, lanthanide-induced pseudocontact shifts (PCSs) have been established as a structural tool for globular proteins. Here, we demonstrate that a PCS-based approach can be successfully applied for the structure determination of integral membrane proteins. Using the 7TM α-helical microbial receptor pSRII, we show that PCS-derived restraints from lanthanide binding tags attached to four different positions of the protein facilitate the backbone structure determination when combined with a limited set of NOEs. In contrast, the same set of NOEs fails to determine the correct 3D fold. The latter situation is frequently encountered in polytopical α-helical membrane proteins and a PCS approach is thus suitable even for this particularly challenging class of membrane proteins. The ease of measuring PCSs makes this an attractive route for structure determination of large membrane proteins in general.
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Affiliation(s)
- Duncan J. Crick
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Jue X. Wang
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Bim Graham
- Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, Australia
| | - James D. Swarbrick
- Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, Australia
| | - Helen R. Mott
- Department of Biochemistry, University of Cambridge, Cambridge, UK
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92
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Finzel K, Lee DJ, Burkart MD. Using modern tools to probe the structure-function relationship of fatty acid synthases. Chembiochem 2015; 16:528-547. [PMID: 25676190 PMCID: PMC4545599 DOI: 10.1002/cbic.201402578] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Indexed: 12/25/2022]
Abstract
Fatty acid biosynthesis is essential to life and represents one of the most conserved pathways in nature, preserving the same handful of chemical reactions across all species. Recent interest in the molecular details of the de novo fatty acid synthase (FAS) has been heightened by demand for renewable fuels and the emergence of multidrug-resistant bacterial strains. Central to FAS is the acyl carrier protein (ACP), a protein chaperone that shuttles the growing acyl chain between catalytic enzymes within the FAS. Human efforts to alter fatty acid biosynthesis for oil production, chemical feedstock, or antimicrobial purposes has been met with limited success, due in part to a lack of detailed molecular information behind the ACP-partner protein interactions inherent to the pathway. This review will focus on recently developed tools for the modification of ACP and analysis of protein-protein interactions, such as mechanism-based crosslinking, and the studies exploiting them. Discussion specific to each enzymatic domain will focus first on mechanism and known inhibitors, followed by available structures and known interactions with ACP. Although significant unknowns remain, new understandings of the intricacies of FAS point to future advances in manipulating this complex molecular factory.
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Affiliation(s)
- Kara Finzel
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358 (USA)
| | - D. John Lee
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358 (USA)
| | - Michael D. Burkart
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358 (USA)
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93
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Piccioli M, Turano P. Transient iron coordination sites in proteins: Exploiting the dual nature of paramagnetic NMR. Coord Chem Rev 2015. [DOI: 10.1016/j.ccr.2014.05.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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94
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Brutscher B, Felli IC, Gil-Caballero S, Hošek T, Kümmerle R, Piai A, Pierattelli R, Sólyom Z. NMR Methods for the Study of Instrinsically Disordered Proteins Structure, Dynamics, and Interactions: General Overview and Practical Guidelines. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 870:49-122. [PMID: 26387100 DOI: 10.1007/978-3-319-20164-1_3] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Thanks to recent improvements in NMR instrumentation, pulse sequence design, and sample preparation, a panoply of new NMR tools has become available for atomic resolution characterization of intrinsically disordered proteins (IDPs) that are optimized for the particular chemical and spectroscopic properties of these molecules. A wide range of NMR observables can now be measured on increasingly complex IDPs that report on their structural and dynamic properties in isolation, as part of a larger complex, or even inside an entire living cell. Herein we present basic NMR concepts, as well as optimised tools available for the study of IDPs in solution. In particular, the following sections are discussed hereafter: a short introduction to NMR spectroscopy and instrumentation (Sect. 3.1), the effect of order and disorder on NMR observables (Sect. 3.2), particular challenges and bottlenecks for NMR studies of IDPs (Sect. 3.3), 2D HN and CON NMR experiments: the fingerprint of an IDP (Sect. 3.4), tools for overcoming major bottlenecks of IDP NMR studies (Sect. 3.5), 13C detected experiments (Sect. 3.6), from 2D to 3D: from simple snapshots to site-resolved characterization of IDPs (Sect. 3.7), sequential NMR assignment: 3D experiments (Sect. 3.8), high-dimensional NMR experiments (nD, with n>3) (Sect. 3.9) and conclusions and perspectives (Sect. 3.10).
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Affiliation(s)
- Bernhard Brutscher
- Institut de Biologie Structurale, Université Grenoble 1, CNRS, CEA, 71 avenue des Martyrs, 38044, Grenoble Cedex 9, France.
| | - Isabella C Felli
- CERM and Department of Chemistry "Ugo Schiff", University of Florence, 50019, Via Luigi Sacconi 6, Sesto Fiorentino, Florence, Italy.
| | | | - Tomáš Hošek
- CERM and Department of Chemistry "Ugo Schiff", University of Florence, 50019, Via Luigi Sacconi 6, Sesto Fiorentino, Florence, Italy
| | - Rainer Kümmerle
- Bruker BioSpin AG, Industriestrasse 26, 8117, Fällanden, Switzerland
| | - Alessandro Piai
- CERM and Department of Chemistry "Ugo Schiff", University of Florence, 50019, Via Luigi Sacconi 6, Sesto Fiorentino, Florence, Italy
| | - Roberta Pierattelli
- CERM and Department of Chemistry "Ugo Schiff", University of Florence, 50019, Via Luigi Sacconi 6, Sesto Fiorentino, Florence, Italy.
| | - Zsófia Sólyom
- Institut de Biologie Structurale, Université Grenoble 1, CNRS, CEA, 71 avenue des Martyrs, 38044, Grenoble Cedex 9, France
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95
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Kragelj J, Blackledge M, Jensen MR. Ensemble Calculation for Intrinsically Disordered Proteins Using NMR Parameters. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 870:123-47. [PMID: 26387101 DOI: 10.1007/978-3-319-20164-1_4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Intrinsically disordered proteins (IDPs) perform their function despite their lack of well-defined tertiary structure. Residual structure has been observed in IDPs, commonly described as transient/dynamic or expressed in terms of fractional populations. In order to understand how the protein primary sequence dictates the dynamic and structural properties of IDPs and in general to understand how IDPs function, atomic-level descriptions are needed. Nuclear magnetic resonance spectroscopy provides information about local and long-range structure in IDPs at amino acid specific resolution and can be used in combination with ensemble descriptions to represent the dynamic nature of IDPs. In this chapter we describe sample-and-select approaches for ensemble modelling of local structural propensities in IDPs with specific emphasis on validation of these ensembles.
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Affiliation(s)
- Jaka Kragelj
- IBS, University Grenoble Alpes, 38044, Grenoble, France.,IBS, CNRS, 38044, Grenoble, France.,IBS, CEA, 38044, Grenoble, France
| | - Martin Blackledge
- IBS, University Grenoble Alpes, 38044, Grenoble, France.,IBS, CNRS, 38044, Grenoble, France.,IBS, CEA, 38044, Grenoble, France
| | - Malene Ringkjøbing Jensen
- IBS, University Grenoble Alpes, 38044, Grenoble, France. .,IBS, CNRS, 38044, Grenoble, France. .,IBS, CEA, 38044, Grenoble, France.
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96
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Sato S, Takeuchi R, Yagi-Utsumi M, Yamaguchi T, Yamaguchi Y, Kato K, Fujita M. A self-assembled, π-stacked complex as a finely-tunable magnetic aligner for biomolecular NMR applications. Chem Commun (Camb) 2015; 51:2540-3. [DOI: 10.1039/c4cc09354b] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The 1D aggregates of π-stacked self-assembled complexes worked as magnetic aligners upon an analyte protein to observe RDC in NMR.
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Affiliation(s)
- Sota Sato
- Department of Applied Chemistry
- School of Engineering
- The University of Tokyo
- Tokyo 113-8656
- Japan
| | - Ryosuke Takeuchi
- Department of Applied Chemistry
- School of Engineering
- The University of Tokyo
- Tokyo 113-8656
- Japan
| | - Maho Yagi-Utsumi
- Department of Life and Coordination-Complex Molecular Science
- Institute for Molecular Science and Department of Bioorganization Research
- Okazaki Institute for Integrative Bioscience
- National Institutes of Natural Sciences
- Okazaki
| | - Takumi Yamaguchi
- Department of Life and Coordination-Complex Molecular Science
- Institute for Molecular Science and Department of Bioorganization Research
- Okazaki Institute for Integrative Bioscience
- National Institutes of Natural Sciences
- Okazaki
| | - Yoshiki Yamaguchi
- Structural Glycobiology Team
- Systems Glycobiology Research Group
- RIKEN-Max Planck Joint Research Center for Systems Chemical Biology
- RIKEN Global Research Cluster
- Wako
| | - Koichi Kato
- Department of Life and Coordination-Complex Molecular Science
- Institute for Molecular Science and Department of Bioorganization Research
- Okazaki Institute for Integrative Bioscience
- National Institutes of Natural Sciences
- Okazaki
| | - Makoto Fujita
- Department of Applied Chemistry
- School of Engineering
- The University of Tokyo
- Tokyo 113-8656
- Japan
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97
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Rinaldelli M, Carlon A, Ravera E, Parigi G, Luchinat C. FANTEN: a new web-based interface for the analysis of magnetic anisotropy-induced NMR data. JOURNAL OF BIOMOLECULAR NMR 2015; 61:21-34. [PMID: 25416616 DOI: 10.1007/s10858-014-9877-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 11/15/2014] [Indexed: 05/17/2023]
Abstract
Pseudocontact shifts (PCSs) and residual dipolar couplings (RDCs) arising from the presence of paramagnetic metal ions in proteins as well as RDCs due to partial orientation induced by external orienting media are nowadays routinely measured as a part of the NMR characterization of biologically relevant systems. PCSs and RDCs are becoming more and more popular as restraints (1) to determine and/or refine protein structures in solution, (2) to monitor the extent of conformational heterogeneity in systems composed of rigid domains which can reorient with respect to one another, and (3) to obtain structural information in protein-protein complexes. The use of both PCSs and RDCs proceeds through the determination of the anisotropy tensors which are at the origin of these NMR observables. A new user-friendly web tool, called FANTEN (Finding ANisotropy TENsors), has been developed for the determination of the anisotropy tensors related to PCSs and RDCs and has been made freely available through the WeNMR ( http://fanten-enmr.cerm.unifi.it:8080 ) gateway. The program has many new features not available in other existing programs, among which the possibility of a joint analysis of several sets of PCS and RDC data and the possibility to perform rigid body minimizations.
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Affiliation(s)
- Mauro Rinaldelli
- CERM and Department of Chemistry "Ugo Schiff", University of Florence, via Sacconi 6, Sesto Fiorentino, Florence, Italy
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98
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Simin M, Irausquin S, Cole CA, Valafar H. Improvements to REDCRAFT: a software tool for simultaneous characterization of protein backbone structure and dynamics from residual dipolar couplings. JOURNAL OF BIOMOLECULAR NMR 2014; 60:241-264. [PMID: 25403759 DOI: 10.1007/s10858-014-9871-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 10/30/2014] [Indexed: 06/04/2023]
Abstract
Within the past two decades, there has been an increase in the acquisition of residual dipolar couplings (RDC) for investigations of biomolecular structures. Their use however is still not as widely adopted as the traditional methods of structure determination by NMR, despite their potential for extending the limits in studies that examine both the structure and dynamics of biomolecules. This is in part due to the difficulties associated with the analysis of this information-rich data type. The software analysis tool REDCRAFT was previously introduced to address some of these challenges. Here we describe and evaluate a number of additional features that have been incorporated in order to extend its computational and analytical capabilities. REDCRAFT's more traditional enhancements integrate a modified steric collision term, as well as structural refinement in the rotamer space. Other, non-traditional improvements include: the filtering of viable structures based on relative order tensor estimates, decimation of the conformational space based on structural similarity, and forward/reverse folding of proteins. Utilizing REDCRAFT's newest features we demonstrate de-novo folding of proteins 1D3Z and 1P7E to within less than 1.6 Å of the corresponding X-ray structures, using as many as four RDCs per residue and as little as two RDCs per residue, in two alignment media. We also show the successful folding of a structure to less than 1.6 Å of the X-ray structure using {C(i-1)-N(i), N(i)-H(i), and C(i-1)-H(i)} RDCs in one alignment medium, and only {N(i)-H(i)} in the second alignment medium (a set of data which can be collected on deuterated samples). The program is available for download from our website at http://ifestos.cse.sc.edu .
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Affiliation(s)
- Mikhail Simin
- Department of Computer Science and Engineering, University of South Carolina, Columbia, SC, 29208, USA
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99
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Ravera E, Salmon L, Fragai M, Parigi G, Al-Hashimi H, Luchinat C. Insights into domain-domain motions in proteins and RNA from solution NMR. Acc Chem Res 2014; 47:3118-26. [PMID: 25148413 PMCID: PMC4204921 DOI: 10.1021/ar5002318] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
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Many multidomain proteins and ribonucleic acids consist of domains
that autonomously fold and that are linked together by flexible junctions.
This architectural design allows domains to sample a wide range of
positions with respect to one another, yet do so in a way that retains
structural specificity, since the number of sampled conformations
remains extremely small compared to the total conformations that would
be sampled if the domains were connected by an infinitely long linker.
This “tuned” flexibility in interdomain conformation
is in turn used in many biochemical processes. There is great
interest in characterizing the dynamic properties
of multidomain systems, and moving beyond conventional descriptions
in terms of static structures, toward the characterization of population-weighted
ensembles describing a distribution of many conformations sampled
in solution. There is also great interest in understanding the design
principles and underlying physical and chemical interactions that
specify the nature of interdomain flexibility. NMR spectroscopy is
one of the most powerful techniques for characterizing motions in
complex biomolecules and has contributed greatly toward our basic
understanding of dynamics in proteins and nucleic acids and its role
in folding, recognition, and signaling. Here, we review methods
that have been developed in our laboratories
to address these challenges. Our approaches are based on the ability
of one domain of the molecule to self-align in a magnetic field, or
to dominate the overall orientation of the molecule, so that the conformational
freedom of other domains can be assessed by their degree of alignment
induced by the aligned part. In turn, this self-alignment ability
can be intrinsic or can be caused by tagging appropriate constructs
to the molecule of interest. In general, self-alignment is due to
magnetic susceptibility anisotropy. Nucleic acids with elongated helices
have this feature, as well as several paramagnetic metal centers that
can be found in, or attached to, a protein domain.
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Affiliation(s)
- Enrico Ravera
- CERM, University of Florence, Via Luigi Sacconi 6, 50019, Sesto Fiorentino, Italy
- Department of Chemistry “U. Schiff”, University of Florence, via della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | - Loïc Salmon
- Department
of Biophysics, University of Michigan, 830 N. University, Ann Arbor, Michigan 48109, United States
| | - Marco Fragai
- CERM, University of Florence, Via Luigi Sacconi 6, 50019, Sesto Fiorentino, Italy
- Department of Chemistry “U. Schiff”, University of Florence, via della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | - Giacomo Parigi
- CERM, University of Florence, Via Luigi Sacconi 6, 50019, Sesto Fiorentino, Italy
- Department of Chemistry “U. Schiff”, University of Florence, via della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | - Hashim Al-Hashimi
- Department
of Biochemistry and Department of Chemistry, Duke University School of Medicine, 307 Research Drive, Durham, North Carolina 27710, United States
| | - Claudio Luchinat
- CERM, University of Florence, Via Luigi Sacconi 6, 50019, Sesto Fiorentino, Italy
- Department of Chemistry “U. Schiff”, University of Florence, via della Lastruccia 3, 50019, Sesto Fiorentino, Italy
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100
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Camacho-Zarco AR, Munari F, Wegstroth M, Liu WM, Ubbink M, Becker S, Zweckstetter M. Multiple paramagnetic effects through a tagged reporter protein. Angew Chem Int Ed Engl 2014; 54:336-9. [PMID: 25293958 DOI: 10.1002/anie.201408615] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Indexed: 11/12/2022]
Abstract
Paramagnetic effects provide unique information about the structure and dynamics of biomolecules. We developed a method in which the lanthanoid tag is not directly attached to the protein of interest, but instead to a "reporter" protein, which binds and then transmits paramagnetic information to the target. The designed method allows access to a large number of paramagnetic restraints and residual dipolar couplings produced from independent molecular alignments in high-molecular-weight proteins with unknown 3D structure.
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Affiliation(s)
- Aldo R Camacho-Zarco
- Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen (Germany); German Center for Neurodegenerative Diseases (DZNE), Göttingen (Germany); Center for the Molecular Physiology of the Brain, University Medical Center, Göttingen (Germany)
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