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Fiorucci L, Schiavina M, Felli IC, Pierattelli R, Ravera E. Are Protein Conformational Ensembles in Agreement with Experimental Data? A Geometrical Interpretation of the Problem. J Chem Inf Model 2024. [PMID: 38959217 DOI: 10.1021/acs.jcim.4c00582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/05/2024]
Abstract
The conformational variability of biological macromolecules can play an important role in their biological function. Therefore, understanding conformational variability is expected to be key for predicting the behavior of a particular molecule in the context of organism-wide studies. Several experimental methods have been developed and deployed for accessing this information, and computational methods are continuously updated for the profitable integration of different experimental sources. The outcome of this endeavor is conformational ensembles, which may vary significantly in properties and composition when different ensemble reconstruction methods are used, and this raises the issue of comparing the predicted ensembles against experimental data. In this article, we discuss a geometrical formulation to provide a framework for understanding the agreement of an ensemble prediction to the experimental observations.
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Affiliation(s)
- Letizia Fiorucci
- Department of Chemistry "Ugo Schiff" and Magnetic Resonance Center (CERM), University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Florence, Italy
- Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP), Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Florence, Italy
| | - Marco Schiavina
- Department of Chemistry "Ugo Schiff" and Magnetic Resonance Center (CERM), University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Florence, Italy
- Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP), Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Florence, Italy
| | - Isabella C Felli
- Department of Chemistry "Ugo Schiff" and Magnetic Resonance Center (CERM), University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Florence, Italy
- Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP), Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Florence, Italy
| | - Roberta Pierattelli
- Department of Chemistry "Ugo Schiff" and Magnetic Resonance Center (CERM), University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Florence, Italy
- Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP), Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Florence, Italy
| | - Enrico Ravera
- Department of Chemistry "Ugo Schiff" and Magnetic Resonance Center (CERM), University of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Florence, Italy
- Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP), Via Luigi Sacconi 6, 50019 Sesto Fiorentino, Florence, Italy
- Florence Data Science, University of Florence, Viale G.B. Morgagni 59, 50134 Florence, Italy
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2
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Gigli L, Silva JM, Cerofolini L, Macedo AL, Geraldes CFGC, Suturina EA, Calderone V, Fragai M, Parigi G, Ravera E, Luchinat C. Machine Learning-Enhanced Quantum Chemistry-Assisted Refinement of the Active Site Structure of Metalloproteins. Inorg Chem 2024; 63:10713-10725. [PMID: 38805564 DOI: 10.1021/acs.inorgchem.4c01274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2024]
Abstract
Understanding the fine structural details of inhibitor binding at the active site of metalloenzymes can have a profound impact on the rational drug design targeted to this broad class of biomolecules. Structural techniques such as NMR, cryo-EM, and X-ray crystallography can provide bond lengths and angles, but the uncertainties in these measurements can be as large as the range of values that have been observed for these quantities in all the published structures. This uncertainty is far too large to allow for reliable calculations at the quantum chemical (QC) levels for developing precise structure-activity relationships or for improving the energetic considerations in protein-inhibitor studies. Therefore, the need arises to rely upon computational methods to refine the active site structures well beyond the resolution obtained with routine application of structural methods. In a recent paper, we have shown that it is possible to refine the active site of cobalt(II)-substituted MMP12, a metalloprotein that is a relevant drug target, by matching to the experimental pseudocontact shifts (PCS) those calculated using multireference ab initio QC methods. The computational cost of this methodology becomes a significant bottleneck when the starting structure is not sufficiently close to the final one, which is often the case with biomolecular structures. To tackle this problem, we have developed an approach based on a neural network (NN) and a support vector regression (SVR) and applied it to the refinement of the active site structure of oxalate-inhibited human carbonic anhydrase 2 (hCAII), another prototypical metalloprotein target. The refined structure gives a remarkably good agreement between the QC-calculated and the experimental PCS. This study not only contributes to the knowledge of CAII but also demonstrates the utility of combining machine learning (ML) algorithms with QC calculations, offering a promising avenue for investigating other drug targets and complex biological systems in general.
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Affiliation(s)
- Lucia Gigli
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino 50019, Italy
- Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino 50019, Italy
- Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Sesto Fiorentino 50019, Italy
| | - José Malanho Silva
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino 50019, Italy
- Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino 50019, Italy
- Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Sesto Fiorentino 50019, Italy
- UCIBIO, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2819-516 Caparica, Portugal
| | - Linda Cerofolini
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino 50019, Italy
- Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino 50019, Italy
- Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Sesto Fiorentino 50019, Italy
| | - Anjos L Macedo
- UCIBIO, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2819-516 Caparica, Portugal
- Associate Laboratory i4HB─Institute for Health and Bioeconomy, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2819-516 Caparica, Portugal
| | - Carlos F G C Geraldes
- Department of Life Sciences, Faculty of Science and Technology, 3000-393 Coimbra, Portugal
- Coimbra Chemistry Center─Institute of Molecular Sciences (CCC-IMS), University of Coimbra, 3004-535 Coimbra, Portugal
| | | | - Vito Calderone
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino 50019, Italy
- Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino 50019, Italy
- Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Sesto Fiorentino 50019, Italy
| | - Marco Fragai
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino 50019, Italy
- Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino 50019, Italy
- Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Sesto Fiorentino 50019, Italy
| | - Giacomo Parigi
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino 50019, Italy
- Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino 50019, Italy
- Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Sesto Fiorentino 50019, Italy
| | - Enrico Ravera
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino 50019, Italy
- Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino 50019, Italy
- Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Sesto Fiorentino 50019, Italy
- Florence Data Science, University of Florence, Florence 50134, Italy
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino 50019, Italy
- Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino 50019, Italy
- Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Sesto Fiorentino 50019, Italy
- Giotto Biotech, S.R.L., Sesto Fiorentino 50019, Italy
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3
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Silva JM, Cerofolini L, Carvalho AL, Ravera E, Fragai M, Parigi G, Macedo AL, Geraldes CFGC, Luchinat C. Elucidating the concentration-dependent effects of thiocyanate binding to carbonic anhydrase. J Inorg Biochem 2023; 244:112222. [PMID: 37068394 DOI: 10.1016/j.jinorgbio.2023.112222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 03/28/2023] [Accepted: 04/09/2023] [Indexed: 04/19/2023]
Abstract
Many proteins naturally carry metal centers, with a large share of them being in the active sites of several enzymes. Paramagnetic effects are a powerful source of structural information and, therefore, if the native metal is paramagnetic, or it can be functionally substituted with a paramagnetic one, paramagnetic effects can be used to study the metal sites, as well as the overall structure of the protein. One notable example is cobalt(II) substitution for zinc(II) in carbonic anhydrase. In this manuscript we investigate the effects of sodium thiocyanate on the chemical environment of the metal ion of the human carbonic anhydrase II. The electron paramagnetic resonance (EPR) titration of the cobalt(II) protein with thiocyanate shows that the EPR spectrum changes from A-type to C-type on passing from 1:1 to 1:1000-fold ligand excess. This indicates the occurrence of a change in the electronic structure, which may reflect a sizable change in the metal coordination environment in turn caused by a modification of the frozen solvent glass. However, paramagnetic nuclear magnetic resonance (NMR) data indicate that the metal coordination cage remains unperturbed even in 1:1000-fold ligand excess. This result proves that the C-type EPR spectrum observed at large ligand concentration should be ascribed to the low temperature at which EPR measurements are performed, which impacts on the structure of the protein when it is destabilized by a high concentration of a chaotropic agent.
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Affiliation(s)
- José Malanho Silva
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino 50019, Italy; UCIBIO, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2819-516 Caparica, Portugal
| | - Linda Cerofolini
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino 50019, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino 50019, Italy
| | - Ana Luísa Carvalho
- UCIBIO, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2819-516 Caparica, Portugal; Associate Laboratory i4HB - Institute for Health and Bioeconomy, NOVA School of Science and Technology, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Enrico Ravera
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino 50019, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino 50019, Italy; Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Sesto Fiorentino, 50019, Italy
| | - Marco Fragai
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino 50019, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino 50019, Italy; Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Sesto Fiorentino, 50019, Italy
| | - Giacomo Parigi
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino 50019, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino 50019, Italy; Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Sesto Fiorentino, 50019, Italy
| | - Anjos L Macedo
- UCIBIO, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2819-516 Caparica, Portugal; Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino 50019, Italy
| | - Carlos F G C Geraldes
- Department of Life Sciences, Faculty of Science and Technology, 3000-393 Coimbra, Portugal; Coimbra Chemistry Center- Institute of Molecular Sciences (CCC-IMS), University of Coimbra, 3004-535 Coimbra, Portugal
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino 50019, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Sesto Fiorentino 50019, Italy; Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), Sesto Fiorentino, 50019, Italy; Giotto Biotech, S.R.L, Sesto Fiorentino, Florence 50019, Italy.
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4
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Andrałojć W, Wieruszewska J, Pasternak K, Gdaniec Z. Solution Structure of a Lanthanide-binding DNA Aptamer Determined Using High Quality pseudocontact shift restraints. Chemistry 2022; 28:e202202114. [PMID: 36043489 PMCID: PMC9828363 DOI: 10.1002/chem.202202114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Indexed: 01/12/2023]
Abstract
In this contribution we report the high-resolution NMR structure of a recently identified lanthanide-binding aptamer (LnA). We demonstrate that the rigid lanthanide binding by LnA allows for the measurement of anisotropic paramagnetic NMR restraints which to date remain largely inaccessible for nucleic acids. One type of such restraints - pseudocontact shifts (PCS) induced by four different paramagnetic lanthanides - was extensively used throughout the current structure determination study and the measured PCS turned out to be exceptionally well reproduced by the final aptamer structure. This finding opens the perspective for a broader application of paramagnetic effects in NMR studies of nucleic acids through the transplantation of the binding site found in LnA into other DNA/RNA systems.
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Affiliation(s)
- Witold Andrałojć
- Institute of Bioorganic ChemistryPolish Academy of SciencesNoskowskiego 12/1461-704 PoznanPoland
| | - Julia Wieruszewska
- Institute of Bioorganic ChemistryPolish Academy of SciencesNoskowskiego 12/1461-704 PoznanPoland
| | - Karol Pasternak
- Institute of Bioorganic ChemistryPolish Academy of SciencesNoskowskiego 12/1461-704 PoznanPoland
| | - Zofia Gdaniec
- Institute of Bioorganic ChemistryPolish Academy of SciencesNoskowskiego 12/1461-704 PoznanPoland
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5
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Srour B, Gervason S, Hoock MH, Monfort B, Want K, Larkem D, Trabelsi N, Landrot G, Zitolo A, Fonda E, Etienne E, Gerbaud G, Müller CS, Oltmanns J, Gordon JB, Yadav V, Kleczewska M, Jelen M, Toledano MB, Dutkiewicz R, Goldberg DP, Schünemann V, Guigliarelli B, Burlat B, Sizun C, D'Autréaux B. Iron Insertion at the Assembly Site of the ISCU Scaffold Protein Is a Conserved Process Initiating Fe-S Cluster Biosynthesis. J Am Chem Soc 2022; 144:17496-17515. [PMID: 36121382 PMCID: PMC10163866 DOI: 10.1021/jacs.2c06338] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Iron-sulfur (Fe-S) clusters are prosthetic groups of proteins biosynthesized on scaffold proteins by highly conserved multi-protein machineries. Biosynthesis of Fe-S clusters into the ISCU scaffold protein is initiated by ferrous iron insertion, followed by sulfur acquisition, via a still elusive mechanism. Notably, whether iron initially binds to the ISCU cysteine-rich assembly site or to a cysteine-less auxiliary site via N/O ligands remains unclear. We show here by SEC, circular dichroism (CD), and Mössbauer spectroscopies that iron binds to the assembly site of the monomeric form of prokaryotic and eukaryotic ISCU proteins via either one or two cysteines, referred to the 1-Cys and 2-Cys forms, respectively. The latter predominated at pH 8.0 and correlated with the Fe-S cluster assembly activity, whereas the former increased at a more acidic pH, together with free iron, suggesting that it constitutes an intermediate of the iron insertion process. Iron not binding to the assembly site was non-specifically bound to the aggregated ISCU, ruling out the existence of a structurally defined auxiliary site in ISCU. Characterization of the 2-Cys form by site-directed mutagenesis, CD, NMR, X-ray absorption, Mössbauer, and electron paramagnetic resonance spectroscopies showed that the iron center is coordinated by four strictly conserved amino acids of the assembly site, Cys35, Asp37, Cys61, and His103, in a tetrahedral geometry. The sulfur receptor Cys104 was at a very close distance and apparently bound to the iron center when His103 was missing, which may enable iron-dependent sulfur acquisition. Altogether, these data provide the structural basis to elucidate the Fe-S cluster assembly process and establish that the initiation of Fe-S cluster biosynthesis by insertion of a ferrous iron in the assembly site of ISCU is a conserved mechanism.
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Affiliation(s)
- Batoul Srour
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Sylvain Gervason
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Maren Hellen Hoock
- Fachbereich Physik, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 56, 67663 Kaiserslautern, Germany
| | - Beata Monfort
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Kristian Want
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Djabir Larkem
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Nadine Trabelsi
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Gautier Landrot
- Synchrotron SOLEIL, L'Orme des Merisiers, BP48 Saint Aubin 91192 Gif-Sur-Yvette, France
| | - Andrea Zitolo
- Synchrotron SOLEIL, L'Orme des Merisiers, BP48 Saint Aubin 91192 Gif-Sur-Yvette, France
| | - Emiliano Fonda
- Synchrotron SOLEIL, L'Orme des Merisiers, BP48 Saint Aubin 91192 Gif-Sur-Yvette, France
| | - Emilien Etienne
- Aix Marseille Univ, CNRS, Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP), 31 Chemin Joseph Aiguier, 13402 Marseille, France
| | - Guillaume Gerbaud
- Aix Marseille Univ, CNRS, Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP), 31 Chemin Joseph Aiguier, 13402 Marseille, France
| | - Christina Sophia Müller
- Fachbereich Physik, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 56, 67663 Kaiserslautern, Germany
| | - Jonathan Oltmanns
- Fachbereich Physik, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 56, 67663 Kaiserslautern, Germany
| | - Jesse B Gordon
- Department of Chemistry, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland 21218, United States
| | - Vishal Yadav
- Department of Chemistry, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland 21218, United States
| | - Malgorzata Kleczewska
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307 Gdansk, Poland
| | - Marcin Jelen
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307 Gdansk, Poland
| | - Michel B Toledano
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Rafal Dutkiewicz
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307 Gdansk, Poland
| | - David P Goldberg
- Department of Chemistry, The Johns Hopkins University, 3400 N. Charles Street, Baltimore, Maryland 21218, United States
| | - Volker Schünemann
- Fachbereich Physik, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 56, 67663 Kaiserslautern, Germany
| | - Bruno Guigliarelli
- Aix Marseille Univ, CNRS, Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP), 31 Chemin Joseph Aiguier, 13402 Marseille, France
| | - Bénédicte Burlat
- Aix Marseille Univ, CNRS, Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP), 31 Chemin Joseph Aiguier, 13402 Marseille, France
| | - Christina Sizun
- Institut de Chimie des Substances Naturelles, CNRS, Université Paris Saclay, Avenue de La Terrasse, 91190 Gif-sur-Yvette, France
| | - Benoit D'Autréaux
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
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6
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Chen JL, Li B, Ma B, Su XC. Distinct stereospecific effect of chiral tether between a tag and protein on the rigidity of paramagnetic tag. JOURNAL OF BIOMOLECULAR NMR 2022; 76:107-119. [PMID: 35841475 DOI: 10.1007/s10858-022-00399-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Accepted: 06/28/2022] [Indexed: 06/15/2023]
Abstract
Flexibility between the paramagnetic tag and its protein conjugates is a common yet unresolved issue in the applications of paramagnetic NMR spectroscopy in biological systems. The flexibility greatly attenuates the magnetic anisotropy and compromises paramagnetic effects especially for pseudocontact shift and residual dipolar couplings. Great efforts have been made to improve the rigidity of paramagnetic tag in the protein conjugates, however, the effect of local environment vicinal to the protein ligation site on the paramagnetic effects remains poorly understood. In the present work, the stereospecific effect of chiral tether between the protein and a tag on the paramagnetic effects produced by the tag attached via a D- and L-type linker between the protein and paramagnetic metal chelating moiety was assessed. The remarkable chiral effect of the D- and L-type tether between the tag and the protein on the rigidity of paramagnetic tag is disclosed in a number of protein-tag-Ln complexes. The chiral tether formed between the D-type tag and L-type protein surface minimizes the effect of the local environment surrounding the ligation site on the averaging of paramagnetic tag, which is helpful to preserve the rigidity of a paramagnetic tag in the protein conjugates.
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Affiliation(s)
- Jia-Liang Chen
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Bin Li
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Bo Ma
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Xun-Cheng Su
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China.
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7
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Ravera E, Gigli L, Fiorucci L, Luchinat C, Parigi G. The evolution of paramagnetic NMR as a tool in structural biology. Phys Chem Chem Phys 2022; 24:17397-17416. [PMID: 35849063 DOI: 10.1039/d2cp01838a] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Paramagnetic NMR data contain extremely accurate long-range information on metalloprotein structures and, when used in the frame of integrative structural biology approaches, they allow for the retrieval of structural details to a resolution that is not achievable using other techniques. Paramagnetic data thus represent an extremely powerful tool to refine protein models in solution, especially when coupled to X-ray or cryoelectron microscopy data, to monitor the formation of complexes and determine the relative arrangements of their components, and to highlight the presence of conformational heterogeneity. More recently, theoretical and computational advancements in quantum chemical calculations of paramagnetic NMR observables are progressively opening new routes in structural biology, because they allow for the determination of the structure within the coordination sphere of the metal center, thus acting as a loupe on sites that are difficult to observe but very important for protein function.
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Affiliation(s)
- Enrico Ravera
- Magnetic Resonance Center (CERM), University of Florence, via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, via della Lastruccia 3, Sesto Fiorentino, 50019, Italy.,Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.
| | - Lucia Gigli
- Magnetic Resonance Center (CERM), University of Florence, via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, via della Lastruccia 3, Sesto Fiorentino, 50019, Italy.,Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.
| | - Letizia Fiorucci
- Magnetic Resonance Center (CERM), University of Florence, via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, via della Lastruccia 3, Sesto Fiorentino, 50019, Italy.,Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM), University of Florence, via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, via della Lastruccia 3, Sesto Fiorentino, 50019, Italy.,Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.
| | - Giacomo Parigi
- Magnetic Resonance Center (CERM), University of Florence, via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, via della Lastruccia 3, Sesto Fiorentino, 50019, Italy.,Consorzio Interuniversitario Risonanze Magnetiche Metallo Proteine (CIRMMP), via Luigi Sacconi 6, Sesto Fiorentino, 50019, Italy.
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8
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Hou XN, Tochio H. Characterizing conformational ensembles of multi-domain proteins using anisotropic paramagnetic NMR restraints. Biophys Rev 2022; 14:55-66. [PMID: 35340613 PMCID: PMC8921464 DOI: 10.1007/s12551-021-00916-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 11/16/2021] [Indexed: 01/13/2023] Open
Abstract
It has been over two decades since paramagnetic NMR started to form part of the essential techniques for structural analysis of proteins under physiological conditions. Paramagnetic NMR has significantly expanded our understanding of the inherent flexibility of proteins, in particular, those that are formed by combinations of two or more domains. Here, we present a brief overview of techniques to characterize conformational ensembles of such multi-domain proteins using paramagnetic NMR restraints produced through anisotropic metals, with a focus on the basics of anisotropic paramagnetic effects, the general procedures of conformational ensemble reconstruction, and some representative reweighting approaches.
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Affiliation(s)
- Xue-Ni Hou
- Department of Biophysics, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, 606-8502 Japan
| | - Hidehito Tochio
- Department of Biophysics, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, 606-8502 Japan
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9
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Müntener T, Joss D, Häussinger D, Hiller S. Pseudocontact Shifts in Biomolecular NMR Spectroscopy. Chem Rev 2022; 122:9422-9467. [PMID: 35005884 DOI: 10.1021/acs.chemrev.1c00796] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Paramagnetic centers in biomolecules, such as specific metal ions that are bound to a protein, affect the nuclei in their surrounding in various ways. One of these effects is the pseudocontact shift (PCS), which leads to strong chemical shift perturbations of nuclear spins, with a remarkably long range of 50 Å and beyond. The PCS in solution NMR is an effect originating from the anisotropic part of the dipole-dipole interaction between the magnetic momentum of unpaired electrons and nuclear spins. The PCS contains spatial information that can be exploited in multiple ways to characterize structure, function, and dynamics of biomacromolecules. It can be used to refine structures, magnify effects of dynamics, help resonance assignments, allows for an intermolecular positioning system, and gives structural information in sensitivity-limited situations where all other methods fail. Here, we review applications of the PCS in biomolecular solution NMR spectroscopy, starting from early works on natural metalloproteins, following the development of non-natural tags to chelate and attach lanthanoid ions to any biomolecular target to advanced applications on large biomolecular complexes and inside living cells. We thus hope to not only highlight past applications but also shed light on the tremendous potential the PCS has in structural biology.
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Affiliation(s)
- Thomas Müntener
- Biozentrum, University of Basel, Spitalstrasse 41, 4056 Basel, Switzerland
| | - Daniel Joss
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Daniel Häussinger
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Sebastian Hiller
- Biozentrum, University of Basel, Spitalstrasse 41, 4056 Basel, Switzerland
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10
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Honorato RV, Koukos PI, Jiménez-García B, Tsaregorodtsev A, Verlato M, Giachetti A, Rosato A, Bonvin AMJJ. Structural Biology in the Clouds: The WeNMR-EOSC Ecosystem. Front Mol Biosci 2021; 8:729513. [PMID: 34395534 PMCID: PMC8356364 DOI: 10.3389/fmolb.2021.729513] [Citation(s) in RCA: 281] [Impact Index Per Article: 93.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 07/13/2021] [Indexed: 12/05/2022] Open
Abstract
Structural biology aims at characterizing the structural and dynamic properties of biological macromolecules at atomic details. Gaining insight into three dimensional structures of biomolecules and their interactions is critical for understanding the vast majority of cellular processes, with direct applications in health and food sciences. Since 2010, the WeNMR project (www.wenmr.eu) has implemented numerous web-based services to facilitate the use of advanced computational tools by researchers in the field, using the high throughput computing infrastructure provided by EGI. These services have been further developed in subsequent initiatives under H2020 projects and are now operating as Thematic Services in the European Open Science Cloud portal (www.eosc-portal.eu), sending >12 millions of jobs and using around 4,000 CPU-years per year. Here we review 10 years of successful e-infrastructure solutions serving a large worldwide community of over 23,000 users to date, providing them with user-friendly, web-based solutions that run complex workflows in structural biology. The current set of active WeNMR portals are described, together with the complex backend machinery that allows distributed computing resources to be harvested efficiently.
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Affiliation(s)
- Rodrigo V Honorato
- Bijvoet Centre for Biomolecular Research, Faculty of Science, Department of Chemistry, Utrecht University, Utrecht, Netherlands
| | - Panagiotis I Koukos
- Bijvoet Centre for Biomolecular Research, Faculty of Science, Department of Chemistry, Utrecht University, Utrecht, Netherlands
| | - Brian Jiménez-García
- Bijvoet Centre for Biomolecular Research, Faculty of Science, Department of Chemistry, Utrecht University, Utrecht, Netherlands
| | | | | | - Andrea Giachetti
- Department of Chemistry and Magnetic Resonance Center, University of Florence, and C.I.R.M.M.P, Fiorentino, Italy
| | - Antonio Rosato
- Department of Chemistry and Magnetic Resonance Center, University of Florence, and C.I.R.M.M.P, Fiorentino, Italy
| | - Alexandre M J J Bonvin
- Bijvoet Centre for Biomolecular Research, Faculty of Science, Department of Chemistry, Utrecht University, Utrecht, Netherlands
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11
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Ravera E, Gigli L, Suturina EA, Calderone V, Fragai M, Parigi G, Luchinat C. A High-Resolution View of the Coordination Environment in a Paramagnetic Metalloprotein from its Magnetic Properties. Angew Chem Int Ed Engl 2021; 60:14960-14966. [PMID: 33595173 DOI: 10.1002/anie.202101149] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Indexed: 12/13/2022]
Abstract
Metalloproteins constitute a significant fraction of the proteome of all organisms and their characterization is critical for both basic sciences and biomedical applications. A large portion of metalloproteins bind paramagnetic metal ions, and paramagnetic NMR spectroscopy has been widely used in their structural characterization. However, the signals of nuclei in the immediate vicinity of the metal center are often broadened beyond detection. In this work, we show that it is possible to determine the coordination environment of the paramagnetic metal in the protein at a resolution inaccessible to other techniques. Taking the structure of a diamagnetic analogue as a starting point, a geometry optimization is carried out by fitting the pseudocontact shifts obtained from first principles quantum chemical calculations to the experimental ones.
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Affiliation(s)
- Enrico Ravera
- Magnetic Resonance Center (CERM), University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP), Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | - Lucia Gigli
- Magnetic Resonance Center (CERM), University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP), Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | | | - Vito Calderone
- Magnetic Resonance Center (CERM), University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP), Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | - Marco Fragai
- Magnetic Resonance Center (CERM), University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP), Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | - Giacomo Parigi
- Magnetic Resonance Center (CERM), University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP), Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM), University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP), Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019, Sesto Fiorentino, Italy
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12
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Ravera E, Gigli L, Suturina EA, Calderone V, Fragai M, Parigi G, Luchinat C. A High‐Resolution View of the Coordination Environment in a Paramagnetic Metalloprotein from its Magnetic Properties. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202101149] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Enrico Ravera
- Magnetic Resonance Center (CERM) University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP) Via L. Sacconi 6 50019 Sesto Fiorentino Italy
- Department of Chemistry “Ugo Schiff” University of Florence Via della Lastruccia 3 50019 Sesto Fiorentino Italy
| | - Lucia Gigli
- Magnetic Resonance Center (CERM) University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP) Via L. Sacconi 6 50019 Sesto Fiorentino Italy
- Department of Chemistry “Ugo Schiff” University of Florence Via della Lastruccia 3 50019 Sesto Fiorentino Italy
| | | | - Vito Calderone
- Magnetic Resonance Center (CERM) University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP) Via L. Sacconi 6 50019 Sesto Fiorentino Italy
- Department of Chemistry “Ugo Schiff” University of Florence Via della Lastruccia 3 50019 Sesto Fiorentino Italy
| | - Marco Fragai
- Magnetic Resonance Center (CERM) University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP) Via L. Sacconi 6 50019 Sesto Fiorentino Italy
- Department of Chemistry “Ugo Schiff” University of Florence Via della Lastruccia 3 50019 Sesto Fiorentino Italy
| | - Giacomo Parigi
- Magnetic Resonance Center (CERM) University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP) Via L. Sacconi 6 50019 Sesto Fiorentino Italy
- Department of Chemistry “Ugo Schiff” University of Florence Via della Lastruccia 3 50019 Sesto Fiorentino Italy
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM) University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP) Via L. Sacconi 6 50019 Sesto Fiorentino Italy
- Department of Chemistry “Ugo Schiff” University of Florence Via della Lastruccia 3 50019 Sesto Fiorentino Italy
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13
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Abstract
The variety of magnetic properties exhibited by paramagnetic lanthanoids provides outstanding information in NMR-based structural biology and therefore can be a very useful tool for characterizing lanthanoid-binding proteins. Because of their dependence on the relative positions of the protein nuclei and of the lanthanoid ion, the paramagnetic restraints (PCS, PRDC and PRE) provide information on structure and dynamics of proteins. In this Chapter, we cover the use of lanthanoids in structural biology including protein sample preparation, NMR experiments and data interpretation.
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14
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Wang Y, An L, Yang Y, Yao L. Generating Five Independent Molecular Alignments for Simultaneous Protein Structure and Dynamics Determination Using Nuclear Magnetic Resonance Spectroscopy. Anal Chem 2020; 92:15263-15269. [PMID: 33166130 DOI: 10.1021/acs.analchem.0c02882] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Residual dipolar couplings (RDCs) are commonly used in NMR for protein structure and dynamics studies, but it is challenging to generate five independent RDC data sets (required for simultaneous structure and dynamics determination) for most protein molecules in the magnetic field. In this work, a reporter protein with a lanthanide tag is introduced to create five independent alignments. This reporter protein is then attached to target proteins where five independent sets of RDCs are also obtained for the target proteins. The fitting of RDCs provides important information about the structure and dynamics of the target proteins. The method is simple and effective and, in principle, can be used to generate complete sets of RDCs for different protein molecules.
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Affiliation(s)
| | - Liaoyuan An
- University of Chinese Academy of Sciences, Beijing 100049, China
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15
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Softley CA, Bostock MJ, Popowicz GM, Sattler M. Paramagnetic NMR in drug discovery. JOURNAL OF BIOMOLECULAR NMR 2020; 74:287-309. [PMID: 32524233 PMCID: PMC7311382 DOI: 10.1007/s10858-020-00322-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 05/26/2020] [Indexed: 05/05/2023]
Abstract
The presence of an unpaired electron in paramagnetic molecules generates significant effects in NMR spectra, which can be exploited to provide restraints complementary to those used in standard structure-calculation protocols. NMR already occupies a central position in drug discovery for its use in fragment screening, structural biology and validation of ligand-target interactions. Paramagnetic restraints provide unique opportunities, for example, for more sensitive screening to identify weaker-binding fragments. A key application of paramagnetic NMR in drug discovery, however, is to provide new structural restraints in cases where crystallography proves intractable. This is particularly important at early stages in drug-discovery programs where crystal structures of weakly-binding fragments are difficult to obtain and crystallization artefacts are probable, but structural information about ligand poses is crucial to guide medicinal chemistry. Numerous applications show the value of paramagnetic restraints to filter computational docking poses and to generate interaction models. Paramagnetic relaxation enhancements (PREs) generate a distance-dependent effect, while pseudo-contact shift (PCS) restraints provide both distance and angular information. Here, we review strategies for introducing paramagnetic centers and discuss examples that illustrate the utility of paramagnetic restraints in drug discovery. Combined with standard approaches, such as chemical shift perturbation and NOE-derived distance information, paramagnetic NMR promises a valuable source of information for many challenging drug-discovery programs.
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Affiliation(s)
- Charlotte A Softley
- Biomolecular NMR and Center for Integrated Protein Science Munich at Department Chemie, Technical University of Munich, Lichtenbergstraße 4, 85747, Garching, Germany
- Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764, Neuherberg, Germany
| | - Mark J Bostock
- Biomolecular NMR and Center for Integrated Protein Science Munich at Department Chemie, Technical University of Munich, Lichtenbergstraße 4, 85747, Garching, Germany
- Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764, Neuherberg, Germany
| | - Grzegorz M Popowicz
- Biomolecular NMR and Center for Integrated Protein Science Munich at Department Chemie, Technical University of Munich, Lichtenbergstraße 4, 85747, Garching, Germany
- Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764, Neuherberg, Germany
| | - Michael Sattler
- Biomolecular NMR and Center for Integrated Protein Science Munich at Department Chemie, Technical University of Munich, Lichtenbergstraße 4, 85747, Garching, Germany.
- Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764, Neuherberg, Germany.
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16
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Denis M, Softley C, Giuntini S, Gentili M, Ravera E, Parigi G, Fragai M, Popowicz G, Sattler M, Luchinat C, Cerofolini L, Nativi C. The Photocatalyzed Thiol-ene reaction: A New Tag to Yield Fast, Selective and reversible Paramagnetic Tagging of Proteins. Chemphyschem 2020; 21:863-869. [PMID: 32092218 PMCID: PMC7384118 DOI: 10.1002/cphc.202000071] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 02/21/2020] [Indexed: 11/18/2022]
Abstract
Paramagnetic restraints have been used in biomolecular NMR for the last three decades to elucidate and refine biomolecular structures, but also to characterize protein-ligand interactions. A common technique to generate such restraints in proteins, which do not naturally contain a (paramagnetic) metal, consists in the attachment to the protein of a lanthanide-binding-tag (LBT). In order to design such LBTs, it is important to consider the efficiency and stability of the conjugation, the geometry of the complex (conformational exchanges and coordination) and the chemical inertness of the ligand. Here we describe a photo-catalyzed thiol-ene reaction for the cysteine-selective paramagnetic tagging of proteins. As a model, we designed an LBT with a vinyl-pyridine moiety which was used to attach our tag to the protein GB1 in fast and irreversible fashion. Our tag T1 yields magnetic susceptibility tensors of significant size with different lanthanides and has been characterized using NMR and relaxometry measurements.
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Affiliation(s)
- Maxime Denis
- Giotto Biotech, S.R.LVia Madonna del piano 650019Sesto Fiorentino (FI)Italy
- Department of Chemistry “Ugo Schiff”University of FlorenceVia della Lastruccia 350019Sesto Fiorentino (FI), Italy
| | - Charlotte Softley
- Biomolecular NMR, Department ChemieTechnical University of MunichLichtenbergstrasse 485747GarchingGermany
- Institute of Structural BiologyHelmholtz Center MunichNeuherbergGermany
| | - Stefano Giuntini
- Department of Chemistry “Ugo Schiff”University of FlorenceVia della Lastruccia 350019Sesto Fiorentino (FI), Italy
- Magnetic Resonance Center (CERM)University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (C.I.R.M.M.P)Via L. Sacconi 650019Sesto FIorentino (FI)Italy
| | - Matteo Gentili
- Giotto Biotech, S.R.LVia Madonna del piano 650019Sesto Fiorentino (FI)Italy
| | - Enrico Ravera
- Magnetic Resonance Center (CERM)University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (C.I.R.M.M.P)Via L. Sacconi 650019Sesto FIorentino (FI)Italy
| | - Giacomo Parigi
- Department of Chemistry “Ugo Schiff”University of FlorenceVia della Lastruccia 350019Sesto Fiorentino (FI), Italy
- Magnetic Resonance Center (CERM)University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (C.I.R.M.M.P)Via L. Sacconi 650019Sesto FIorentino (FI)Italy
| | - Marco Fragai
- Department of Chemistry “Ugo Schiff”University of FlorenceVia della Lastruccia 350019Sesto Fiorentino (FI), Italy
- Magnetic Resonance Center (CERM)University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (C.I.R.M.M.P)Via L. Sacconi 650019Sesto FIorentino (FI)Italy
| | - Grzegorz Popowicz
- Institute of Structural BiologyHelmholtz Center MunichNeuherbergGermany
| | - Michael Sattler
- Biomolecular NMR, Department ChemieTechnical University of MunichLichtenbergstrasse 485747GarchingGermany
- Institute of Structural BiologyHelmholtz Center MunichNeuherbergGermany
| | - Claudio Luchinat
- Department of Chemistry “Ugo Schiff”University of FlorenceVia della Lastruccia 350019Sesto Fiorentino (FI), Italy
- Magnetic Resonance Center (CERM)University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (C.I.R.M.M.P)Via L. Sacconi 650019Sesto FIorentino (FI)Italy
| | - Linda Cerofolini
- Magnetic Resonance Center (CERM)University of Florence, and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (C.I.R.M.M.P)Via L. Sacconi 650019Sesto FIorentino (FI)Italy
| | - Cristina Nativi
- Department of Chemistry “Ugo Schiff”University of FlorenceVia della Lastruccia 350019Sesto Fiorentino (FI), Italy
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17
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Orton H, Huber T, Otting G. Paramagpy: software for fitting magnetic susceptibility tensors using paramagnetic effects measured in NMR spectra. MAGNETIC RESONANCE (GOTTINGEN, GERMANY) 2020; 1:1-12. [PMID: 37904891 PMCID: PMC10500712 DOI: 10.5194/mr-1-1-2020] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 01/20/2020] [Indexed: 11/01/2023]
Abstract
Paramagnetic metal ions with fast-relaxing electrons generate pseudocontact shifts (PCSs), residual dipolar couplings (RDCs), paramagnetic relaxation enhancements (PREs) and cross-correlated relaxation (CCR) in the nuclear magnetic resonance (NMR) spectra of the molecules they bind to. These effects offer long-range structural information in molecules equipped with binding sites for such metal ions. Here we present the new open-source software Paramagpy, which has been written in Python 3 with a graphic user interface. Paramagpy combines the functionalities of different currently available programs to support the fitting of magnetic susceptibility tensors using PCS, RDC, PRE and CCR data and molecular coordinates in Protein Data Bank (PDB) format, including a convenient graphical user interface. Paramagpy uses efficient fitting algorithms to avoid local minima and supports corrections to back-calculated PCS and PRE data arising from cross-correlation effects with chemical shift tensors. The source code is available from 10.5281/zenodo.3594568 .
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Affiliation(s)
- Henry William Orton
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Thomas Huber
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Gottfried Otting
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
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18
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Schirò A, Carlon A, Parigi G, Murshudov G, Calderone V, Ravera E, Luchinat C. On the complementarity of X-ray and NMR data. JOURNAL OF STRUCTURAL BIOLOGY-X 2020; 4:100019. [PMID: 32647823 PMCID: PMC7337059 DOI: 10.1016/j.yjsbx.2020.100019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/28/2019] [Accepted: 01/02/2020] [Indexed: 12/20/2022]
Abstract
X-ray crystallography and NMR contain complementary information for the structural characterization of biological macromolecules. X-ray diffraction is primarily sensitive to the overall shape of the molecule, whereas NMR is mostly sensitive to the atomic detail. Their combination can therefore provide a stronger justification for the resulting structure. For their combination we have recently proposed REFMAC-NMR, which relies on primary data from both techniques for joint refinement. This possibility raises the compelling question of how far the complementarity can be extended. In this paper, we describe an integrative approach to the refinement with NMR data of four X-ray structures of hen-egg-white lysozyme, solved at atomic resolution in four different crystal forms, and we demonstrate that the outcome critically depends on the crystal form itself, reflecting the sensitivity of NMR to fine details.
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Affiliation(s)
- Antonio Schirò
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019 Sesto Fiorentino, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy
| | - Azzurra Carlon
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019 Sesto Fiorentino, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy
| | - Giacomo Parigi
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019 Sesto Fiorentino, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy
| | - Garib Murshudov
- MRC Laboratory for Molecular Biology, Francis Crick Ave, Cambridge CB2 0QH, UK
| | - Vito Calderone
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), 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
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019 Sesto Fiorentino, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019 Sesto Fiorentino, Italy.,Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy
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19
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Joss D, Winter F, Häussinger D. A novel, rationally designed lanthanoid chelating tag delivers large paramagnetic structural restraints for biomolecular NMR. Chem Commun (Camb) 2020; 56:12861-12864. [DOI: 10.1039/d0cc04337k] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel, rationally designed lanthanoid chelating tag enables fast ligation to biomacromolecules and delivers long-range structural restraints by NMR.
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Affiliation(s)
- Daniel Joss
- Department of Chemistry
- University of Basel
- Basel 4056
- Switzerland
| | - Florine Winter
- Department of Chemistry
- University of Basel
- Basel 4056
- Switzerland
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20
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Carlon A, Gigli L, Ravera E, Parigi G, Gronenborn AM, Luchinat C. Assessing Structural Preferences of Unstructured Protein Regions by NMR. Biophys J 2019; 117:1948-1953. [PMID: 31676138 PMCID: PMC7018990 DOI: 10.1016/j.bpj.2019.10.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 09/30/2019] [Accepted: 10/08/2019] [Indexed: 11/28/2022] Open
Abstract
Biomacromolecules, such as proteins, often exhibit significant motions intimately associated with their function. Intrinsically disordered proteins and proteins with intrinsically disordered regions, although extremely important for a plethora of cellular functions, are difficult to structurally characterize at the atomic level because the experimental parameters report on ensemble and time averages. Here, we demonstrate for the C-terminal domain of the human immunodeficiency virus type 1 capsid protein that NMR and, in particular, residual dipolar couplings (RDCs) measured for the folded portion of the protein can inform on the structural preferences of the unstructured portion using RDC-prediction tools and the maximum occurrence approach.
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Affiliation(s)
- Azzurra Carlon
- Magnetic Resonance Center, University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di Metallo Proteine, Sesto Fiorentino, Florence, Italy; Department of Chemistry "Ugo Schiff," University of Florence, Sesto Fiorentino, Florence, Italy
| | - Lucia Gigli
- Magnetic Resonance Center, University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di Metallo Proteine, Sesto Fiorentino, Florence, Italy; Department of Chemistry "Ugo Schiff," University of Florence, Sesto Fiorentino, Florence, Italy
| | - Enrico Ravera
- Magnetic Resonance Center, University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di Metallo Proteine, Sesto Fiorentino, Florence, Italy; Department of Chemistry "Ugo Schiff," University of Florence, Sesto Fiorentino, Florence, Italy
| | - Giacomo Parigi
- Magnetic Resonance Center, University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di Metallo Proteine, Sesto Fiorentino, Florence, Italy; Department of Chemistry "Ugo Schiff," University of Florence, Sesto Fiorentino, Florence, Italy
| | - Angela M Gronenborn
- Department of Structural Biology and Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania.
| | - Claudio Luchinat
- Magnetic Resonance Center, University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di Metallo Proteine, Sesto Fiorentino, Florence, Italy; Department of Chemistry "Ugo Schiff," University of Florence, Sesto Fiorentino, Florence, Italy.
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21
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Parigi G, Ravera E, Luchinat C. Magnetic susceptibility and paramagnetism-based NMR. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2019; 114-115:211-236. [PMID: 31779881 DOI: 10.1016/j.pnmrs.2019.06.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 06/17/2019] [Accepted: 06/17/2019] [Indexed: 05/18/2023]
Abstract
The magnetic interactions between the nuclear magnetic moment and the magnetic moment of unpaired electron(s) depend on the structure and dynamics of the molecules where the paramagnetic center is located and of their partners. The long-range nature of the magnetic interactions is thus a reporter of invaluable information for structural biology studies, when other techniques often do not provide enough data for the atomic-level characterization of the system. This precious information explains the flourishing of paramagnetism-assisted NMR studies in recent years. Many paramagnetic effects are related to the magnetic susceptibility of the paramagnetic metal. Although these effects have been known for more than half a century, different theoretical models and new approaches have been proposed in the last decade. In this review, we have summarized the consequences for NMR spectroscopy of magnetic interactions between nuclear and electron magnetic moments, and thus of the presence of a magnetic susceptibility due to metals, and we do so using a unified notation.
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Affiliation(s)
- Giacomo Parigi
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), 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
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019 Sesto Fiorentino, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019 Sesto Fiorentino, Italy; Department of Chemistry "Ugo Schiff", University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy.
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22
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Carlon A, Ravera E, Parigi G, Murshudov GN, Luchinat C. Joint X-ray/NMR structure refinement of multidomain/multisubunit systems. JOURNAL OF BIOMOLECULAR NMR 2019; 73:265-278. [PMID: 30311122 PMCID: PMC6692505 DOI: 10.1007/s10858-018-0212-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 10/06/2018] [Indexed: 06/08/2023]
Abstract
Data integration in structural biology has become a paradigm for the characterization of biomolecular systems, and it is now accepted that combining different techniques can fill the gaps in each other's blind spots. In this frame, one of the combinations, which we have implemented in REFMAC-NMR, is residual dipolar couplings from NMR together with experimental data from X-ray diffraction. The first are exquisitely sensitive to the local details but does not give any information about overall shape, whereas the latter encodes more the information about the overall shape but at the same time tends to miss the local details even at the highest resolutions. Once crystals are obtained, it is often rather easy to obtain a complete X-ray dataset, however it is time-consuming to obtain an exhaustive NMR dataset. Here, we discuss the effect of including a-priori knowledge on the properties of the system to reduce the number of experimental data needed to obtain a more complete picture. We thus introduce a set of new features of REFMAC-NMR that allow for improved handling of RDC data for multidomain proteins and multisubunit biomolecular complexes, and encompasses the use of pseudo-contact shifts as an additional source of NMR-based information. The new feature may either help in improving the refinement, or assist in spotting differences between the crystal and the solution data. We show three different examples where NMR and X-ray data can be reconciled to a unique structural model without invoking mobility.
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Affiliation(s)
- Azzurra Carlon
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Enrico Ravera
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019 Sesto Fiorentino, Italy
- Department of Chemistry “Ugo Schiff”, University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy
| | - Giacomo Parigi
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019 Sesto Fiorentino, Italy
- Department of Chemistry “Ugo Schiff”, University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy
| | - Garib N. Murshudov
- MRC Laboratory for Molecular Biology, Francis Crick Ave, CB2 0QH Cambridge, UK
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019 Sesto Fiorentino, Italy
- Department of Chemistry “Ugo Schiff”, University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, Italy
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23
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Cerofolini L, Giuntini S, Barbieri L, Pennestri M, Codina A, Fragai M, Banci L, Luchinat E, Ravera E. Real-Time Insights into Biological Events: In-Cell Processes and Protein-Ligand Interactions. Biophys J 2019; 116:239-247. [PMID: 30580921 PMCID: PMC6350048 DOI: 10.1016/j.bpj.2018.11.3132] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 10/30/2018] [Accepted: 11/27/2018] [Indexed: 11/15/2022] Open
Abstract
FlowNMR has the aim of continuously monitoring processes that occur in conditions that are not compatible with being carried out within a closed tube. However, it is sample intensive and not suitable for samples, such as proteins or living cells, that are often available in limited volumes and possibly low concentrations. We here propose a dialysis-based modification of a commercial flowNMR setup that allows for recycling the medium while confining the sample (proteins and cells) within the active volume of the tube. This approach is demonstrated in the specific cases of in-cell NMR and protein-based ligand studies.
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Affiliation(s)
- Linda Cerofolini
- Magnetic Resonance Center, University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine, Sesto Fiorentino, Italy
| | - Stefano Giuntini
- Magnetic Resonance Center, University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine, Sesto Fiorentino, Italy; Department of Chemistry, Ugo Schiff, University of Florence, Sesto Fiorentino, Italy
| | - Letizia Barbieri
- Magnetic Resonance Center, University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine, Sesto Fiorentino, Italy
| | | | - Anna Codina
- Bruker UK Limited, Banner Lane, Coventry, United Kingdom
| | - Marco Fragai
- Magnetic Resonance Center, University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine, Sesto Fiorentino, Italy; Department of Chemistry, Ugo Schiff, University of Florence, Sesto Fiorentino, Italy
| | - Lucia Banci
- Magnetic Resonance Center, University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine, Sesto Fiorentino, Italy; Department of Chemistry, Ugo Schiff, University of Florence, Sesto Fiorentino, Italy
| | - Enrico Luchinat
- Magnetic Resonance Center, University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine, Sesto Fiorentino, Italy; Department of Experimental and Clinical Biomedical Sciences, Mario Serio, University of Florence, Florence, Italy.
| | - Enrico Ravera
- Magnetic Resonance Center, University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine, Sesto Fiorentino, Italy; Department of Chemistry, Ugo Schiff, University of Florence, Sesto Fiorentino, Italy.
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24
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Cerofolini L, Giuntini S, Carlon A, Ravera E, Calderone V, Fragai M, Parigi G, Luchinat C. Characterization of PEGylated Asparaginase: New Opportunities from NMR Analysis of Large PEGylated Therapeutics. Chemistry 2019; 25:1984-1991. [DOI: 10.1002/chem.201804488] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 11/09/2018] [Indexed: 11/12/2022]
Affiliation(s)
- Linda Cerofolini
- Magnetic Resonance Center (CERM)University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di, Metallo Proteine (CIRMMP) Via L. Sacconi 6 50019 Sesto Fiorentino Italy
| | - Stefano Giuntini
- Magnetic Resonance Center (CERM)University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di, Metallo Proteine (CIRMMP) Via L. Sacconi 6 50019 Sesto Fiorentino Italy
- Department of ChemistryUniversity of Florence Via della Lastruccia 3 50019 Sesto Fiorentino Italy
| | - Azzurra Carlon
- Magnetic Resonance Center (CERM)University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di, Metallo Proteine (CIRMMP) Via L. Sacconi 6 50019 Sesto Fiorentino Italy
| | - Enrico Ravera
- Magnetic Resonance Center (CERM)University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di, Metallo Proteine (CIRMMP) Via L. Sacconi 6 50019 Sesto Fiorentino Italy
- Department of ChemistryUniversity of Florence Via della Lastruccia 3 50019 Sesto Fiorentino Italy
| | - Vito Calderone
- Magnetic Resonance Center (CERM)University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di, Metallo Proteine (CIRMMP) Via L. Sacconi 6 50019 Sesto Fiorentino Italy
- Department of ChemistryUniversity of Florence Via della Lastruccia 3 50019 Sesto Fiorentino Italy
| | - Marco Fragai
- Magnetic Resonance Center (CERM)University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di, Metallo Proteine (CIRMMP) Via L. Sacconi 6 50019 Sesto Fiorentino Italy
- Department of ChemistryUniversity of Florence Via della Lastruccia 3 50019 Sesto Fiorentino Italy
| | - Giacomo Parigi
- Magnetic Resonance Center (CERM)University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di, Metallo Proteine (CIRMMP) Via L. Sacconi 6 50019 Sesto Fiorentino Italy
- Department of ChemistryUniversity of Florence Via della Lastruccia 3 50019 Sesto Fiorentino Italy
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM)University of Florence and Consorzio Interuniversitario Risonanze Magnetiche di, Metallo Proteine (CIRMMP) Via L. Sacconi 6 50019 Sesto Fiorentino Italy
- Department of ChemistryUniversity of Florence Via della Lastruccia 3 50019 Sesto Fiorentino Italy
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25
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Sala D, Musiani F, Rosato A. Application of Molecular Dynamics to the Investigation of Metalloproteins Involved in Metal Homeostasis. Eur J Inorg Chem 2018. [DOI: 10.1002/ejic.201800602] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Davide Sala
- Magnetic Resonance Center (CERM); University of Florence; Via Luigi Sacconi 6 50019 Sesto Fiorentino Italy
| | - Francesco Musiani
- Laboratory of Bioinorganic Chemistry; Department of Pharmacy and Biotechnology; University of Bologna; Viale Giuseppe Fanin 40, I 40127 Bologna Italy
| | - Antonio Rosato
- Magnetic Resonance Center (CERM); University of Florence; Via Luigi Sacconi 6 50019 Sesto Fiorentino Italy
- Consorzio Interuniversitario di Risonanze Magnetiche di Metallo Proteine; Via Luigi Sacconi 6 50019 Sesto Fiorentino Italy
- Department of Chemistry; University of Florence; Via della Lastruccia 3 50019 Sesto Fiorentino Italy
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26
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Müntener T, Kottelat J, Huber A, Häussinger D. New Lanthanide Chelating Tags for PCS NMR Spectroscopy with Reduction Stable, Rigid Linkers for Fast and Irreversible Conjugation to Proteins. Bioconjug Chem 2018; 29:3344-3351. [DOI: 10.1021/acs.bioconjchem.8b00512] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Thomas Müntener
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Jérémy Kottelat
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Annika Huber
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Daniel Häussinger
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
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27
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Paramagnetic NMR as a new tool in structural biology. Emerg Top Life Sci 2018; 2:19-28. [DOI: 10.1042/etls20170084] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2017] [Revised: 12/19/2017] [Accepted: 12/20/2017] [Indexed: 12/25/2022]
Abstract
NMR (nuclear magnetic resonance) investigation through the exploitation of paramagnetic effects is passing from an approach limited to few specialists in the field to a generally applicable method that must be considered, especially for the characterization of systems hardly affordable with other techniques. This is mostly due to the fact that paramagnetic data are long range in nature, thus providing information for the structural and dynamic characterization of complex biomolecular architectures in their native environment. On the other hand, this information usually needs to be complemented by data from other sources. Integration of paramagnetic NMR with other techniques, and the development of protocols for a joint analysis of all available data, is fundamental for achieving a comprehensive characterization of complex biological systems. We describe here a few examples of the new possibilities offered by paramagnetic data used in integrated structural approaches.
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28
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Cerofolini L, Staderini T, Giuntini S, Ravera E, Fragai M, Parigi G, Pierattelli R, Luchinat C. Long-range paramagnetic NMR data can provide a closer look on metal coordination in metalloproteins. J Biol Inorg Chem 2017; 23:71-80. [PMID: 29218635 DOI: 10.1007/s00775-017-1511-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 11/06/2017] [Indexed: 11/24/2022]
Abstract
Paramagnetic NMR data can be profitably incorporated in structural refinement protocols of metalloproteins or metal-substituted proteins, mostly as distance or angle restraints. However, they could in principle provide much more information, because the magnetic susceptibility of a paramagnetic metal ion is largely determined by its coordination sphere. This information can in turn be used to evaluate changes occurring in the coordination sphere of the metal when ligands (e.g.: inhibitors) are bound to the protein. This gives an experimental handle on the molecular structure in the vicinity of the metal which falls in the so-called blind sphere. The magnetic susceptibility anisotropy tensors of cobalt(II) and nickel(II) ions bound to human carbonic anhydrase II in free and inhibited forms have been determined. The change of the magnetic susceptibility anisotropy is directly linked to the binding mode of different ligands in the active site of the enzyme. Indication about the metal coordination sphere in the presence of an inhibitor in pharmaceutically relevant proteins could be important in the design of selective drugs with a structure-based approach.
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Affiliation(s)
- Linda Cerofolini
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy
| | - Tommaso Staderini
- Department of Chemistry "Ugo Schiff", University of Florence, Via Della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | - Stefano Giuntini
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), 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
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy
- Department of Chemistry "Ugo Schiff", University of Florence, Via Della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | - Marco Fragai
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy
- Department of Chemistry "Ugo Schiff", University of Florence, Via Della Lastruccia 3, 50019, Sesto Fiorentino, Italy
- Giotto Biotech S.R.L., Via Madonna del Piano 6, 50019, Sesto Fiorentino, Italy
| | - Giacomo Parigi
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy
- Department of Chemistry "Ugo Schiff", University of Florence, Via Della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | - Roberta Pierattelli
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy
- Department of Chemistry "Ugo Schiff", University of Florence, Via Della Lastruccia 3, 50019, Sesto Fiorentino, Italy
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM) and Interuniversity Consortium for Magnetic Resonance of Metallo Proteins (CIRMMP), Via L. Sacconi 6, 50019, Sesto Fiorentino, Italy.
- Department of Chemistry "Ugo Schiff", University of Florence, Via Della Lastruccia 3, 50019, Sesto Fiorentino, Italy.
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29
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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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30
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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: 84] [Impact Index Per Article: 12.0] [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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31
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Sala D, Giachetti A, Luchinat C, Rosato A. A protocol for the refinement of NMR structures using simultaneously pseudocontact shift restraints from multiple lanthanide ions. JOURNAL OF BIOMOLECULAR NMR 2016; 66:175-185. [PMID: 27771862 DOI: 10.1007/s10858-016-0065-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 09/29/2016] [Indexed: 06/06/2023]
Abstract
The binding of paramagnetic metal ions to proteins produces a number of different effects on the NMR spectra of the system. In particular, when the magnetic susceptibility of the metal ion is anisotropic, pseudocontact shifts (PCSs) arise and can be easily measured. They constitute very useful restraints for the solution structure determination of metal-binding proteins. In this context, there has been great interest in the use of lanthanide(III) ions to induce PCSs in diamagnetic proteins, e.g. through the replacement native calcium(II) ions. By preparing multiple samples in each of which a different ion of the lanthanide series is introduced, it is possible to obtain multiple independent PCS datasets that can be used synergistically to generate protein structure ensembles (typically called bundles). For typical NMR-based determination of protein structure, it is necessary to perform an energetic refinement of such initial bundles to obtain final structures whose geometric quality is suitable for deposition in the PDB. This can be conveniently done by using restrained molecular dynamics simulations (rMD) in explicit solvent. However, there are no available protocols for rMD using multiple PCS datasets as part of the restraints. In this work, we extended the PCS module of the AMBER MD package to handle multiple datasets and tuned a previously developed protocol for NMR structure refinement to achieve consistent convergence with PCS restraints. Test calculations with real experimental data show that this new implementation delivers the expected improvement of protein geometry, resulting in final structures that are of suitable quality for deposition. Furthermore, we observe that also initial structures generated only with traditional restraints can be successfully refined using traditional and PCS restraints simultaneously.
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Affiliation(s)
- Davide Sala
- Magnetic Resonance Center (CERM), University of Florence, Via Luigi Sacconi 6, 50019, Sesto Fiorentino, Italy
| | - Andrea Giachetti
- Magnetic Resonance Center (CERM), University of Florence, Via Luigi Sacconi 6, 50019, Sesto Fiorentino, Italy
| | - Claudio Luchinat
- Magnetic Resonance Center (CERM), University of Florence, Via Luigi Sacconi 6, 50019, Sesto Fiorentino, Italy.
- Department of Chemistry, University of Florence, Via della Lastruccia 3, 50019, Sesto Fiorentino, Italy.
| | - Antonio Rosato
- Magnetic Resonance Center (CERM), University of Florence, Via Luigi Sacconi 6, 50019, Sesto Fiorentino, Italy.
- Department of Chemistry, University of Florence, Via della Lastruccia 3, 50019, Sesto Fiorentino, Italy.
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32
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Baldoneschi V, Cerofolini L, Dragoni E, Storai A, Luchinat C, Fragai M, Richichi B, Nativi C. Active-Site Targeting Paramagnetic Probe for Matrix Metalloproteinases. Chempluschem 2016; 81:1333-1338. [DOI: 10.1002/cplu.201600375] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 09/23/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Veronica Baldoneschi
- Department of Chemistry “Ugo Schiff”; University of Florence; Via della Lastruccia 3-13 50019 Sesto Fiorentino Italy
| | - Linda Cerofolini
- Department of Chemistry “Ugo Schiff”; University of Florence; Via della Lastruccia 3-13 50019 Sesto Fiorentino Italy
- CERM; Univeristy of Florence; Via Sacconi 6 50019 Sesto Fiorentino Italy
| | - Elisa Dragoni
- Department of Chemistry “Ugo Schiff”; University of Florence; Via della Lastruccia 3-13 50019 Sesto Fiorentino Italy
| | - Andrea Storai
- Department of Chemistry “Ugo Schiff”; University of Florence; Via della Lastruccia 3-13 50019 Sesto Fiorentino Italy
| | - Claudio Luchinat
- Department of Chemistry “Ugo Schiff”; University of Florence; Via della Lastruccia 3-13 50019 Sesto Fiorentino Italy
- CERM; Univeristy of Florence; Via Sacconi 6 50019 Sesto Fiorentino Italy
| | - Marco Fragai
- Department of Chemistry “Ugo Schiff”; University of Florence; Via della Lastruccia 3-13 50019 Sesto Fiorentino Italy
- CERM; Univeristy of Florence; Via Sacconi 6 50019 Sesto Fiorentino Italy
| | - Barbara Richichi
- Department of Chemistry “Ugo Schiff”; University of Florence; Via della Lastruccia 3-13 50019 Sesto Fiorentino Italy
| | - Cristina Nativi
- Department of Chemistry “Ugo Schiff”; University of Florence; Via della Lastruccia 3-13 50019 Sesto Fiorentino Italy
- CERM; Univeristy of Florence; Via Sacconi 6 50019 Sesto Fiorentino Italy
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33
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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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34
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Yang Y, Huang F, Huber T, Su XC. Site-specific tagging proteins with a rigid, small and stable transition metal chelator, 8-hydroxyquinoline, for paramagnetic NMR analysis. JOURNAL OF BIOMOLECULAR NMR 2016; 64:103-113. [PMID: 26732873 DOI: 10.1007/s10858-016-0011-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 01/01/2016] [Indexed: 06/05/2023]
Abstract
Design of a paramagnetic metal binding motif in a protein is a valuable way for understanding the function, dynamics and interactions of a protein by paramagnetic NMR spectroscopy. Several strategies have been proposed to site-specifically tag proteins with paramagnetic lanthanide ions. Here we report a simple approach of engineering a transition metal binding motif via site-specific labelling of a protein with 2-vinyl-8-hydroxyquinoline (2V-8HQ). The protein-2V-8HQ adduct forms a stable complex with transition metal ions, Mn(II), Co(II), Ni(II), Cu(II) and Zn(II). The paramagnetic effects generated by these transition metal ions were evaluated by NMR spectroscopy. We show that 2V-8HQ is a rigid and stable transition metal binding tag. The coordination of the metal ion can be assisted by protein sidechains. More importantly, tunable paramagnetic tensors are simply obtained in an α-helix that possesses solvent exposed residues in positions i and i + 3, where i is the residue to be mutated to cysteine, i + 3 is Gln or Glu or i - 4 is His. The coordination of a sidechain carboxylate/amide or imidazole to cobalt(II) results in different structural geometries, leading to different paramagnetic tensors as shown by experimental data.
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Affiliation(s)
- Yin Yang
- State Key Laboratory of Elemento-Organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin, 300071, China
| | - Feng Huang
- State Key Laboratory of Elemento-Organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin, 300071, China
| | - Thomas Huber
- Research School of Chemistry, Australian National University, Canberra, ACT, 0200, Australia
| | - Xun-Cheng Su
- State Key Laboratory of Elemento-Organic Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University, Tianjin, 300071, China.
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35
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Carlon A, Ravera E, Hennig J, Parigi G, Sattler M, Luchinat C. Improved Accuracy from Joint X-ray and NMR Refinement of a Protein-RNA Complex Structure. J Am Chem Soc 2016; 138:1601-10. [PMID: 26761154 DOI: 10.1021/jacs.5b11598] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Integrated experimental approaches play an increasingly important role in structural biology, taking advantage of the complementary information provided by different techniques. In particular, the combination of NMR data with X-ray diffraction patterns may provide accurate and precise information about local conformations not available from average-resolution X-ray structures alone. Here, we refined the structure of a ternary protein-protein-RNA complex comprising three domains, Sxl and Unr, bound to a single-stranded region derived in the msl2 mRNA. The joint X-ray and NMR refinement reveals that-despite the poor quality of the fit found for the original structural model-the NMR data can be largely accommodated within the uncertainty in the atom positioning (structural noise) from the primary X-ray data and that the overall domain arrangements and binding interfaces are preserved on passing from the crystalline state to the solution. The refinement highlights local conformational differences, which provide additional information on specific features of the structure. For example, conformational dynamics and heterogeneity observed at the interface between the CSD1 and the Sxl protein components in the ternary complex are revealed by the combination of NMR and crystallographic data. The joint refinement protocol offers unique opportunities to detect structural differences arising from various experimental conditions and reveals static or dynamic differences in the conformation of the biomolecule between the solution and the crystals.
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Affiliation(s)
- Azzurra Carlon
- Magnetic Resonance Center "CERM" and Department of Chemistry "Ugo Schiff", University of Florence and Magnetic Resonance Consortium (CIRMMP) , Via L. Sacconi 6, 50019 Sesto Fiorentino, Firenze, Italy
| | - Enrico Ravera
- Magnetic Resonance Center "CERM" and Department of Chemistry "Ugo Schiff", University of Florence and Magnetic Resonance Consortium (CIRMMP) , Via L. Sacconi 6, 50019 Sesto Fiorentino, Firenze, Italy
| | - Janosch Hennig
- Center for Integrated Protein Science Munich (CIPSM) at Department Chemie, Technische Universität München , 85747 Garching, Germany.,Institute of Structural Biology, Helmholtz Zentrum München , 85764 Neuherberg, Germany
| | - Giacomo Parigi
- Magnetic Resonance Center "CERM" and Department of Chemistry "Ugo Schiff", University of Florence and Magnetic Resonance Consortium (CIRMMP) , Via L. Sacconi 6, 50019 Sesto Fiorentino, Firenze, Italy
| | - Michael Sattler
- Center for Integrated Protein Science Munich (CIPSM) at Department Chemie, Technische Universität München , 85747 Garching, Germany.,Institute of Structural Biology, Helmholtz Zentrum München , 85764 Neuherberg, Germany
| | - Claudio Luchinat
- Magnetic Resonance Center "CERM" and Department of Chemistry "Ugo Schiff", University of Florence and Magnetic Resonance Consortium (CIRMMP) , Via L. Sacconi 6, 50019 Sesto Fiorentino, Firenze, Italy
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