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Lenard AJ, Mulder FAA, Madl T. Solvent paramagnetic relaxation enhancement as a versatile method for studying structure and dynamics of biomolecular systems. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2022; 132-133:113-139. [PMID: 36496256 DOI: 10.1016/j.pnmrs.2022.09.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 09/14/2022] [Accepted: 09/15/2022] [Indexed: 06/17/2023]
Abstract
Solvent paramagnetic relaxation enhancement (sPRE) is a versatile nuclear magnetic resonance (NMR)-based method that allows characterization of the structure and dynamics of biomolecular systems through providing quantitative experimental information on solvent accessibility of NMR-active nuclei. Addition of soluble paramagnetic probes to the solution of a biomolecule leads to paramagnetic relaxation enhancement in a concentration-dependent manner. Here we review recent progress in the sPRE-based characterization of structural and dynamic properties of biomolecules and their complexes, and aim to deliver a comprehensive illustration of a growing number of applications of the method to various biological systems. We discuss the physical principles of sPRE measurements and provide an overview of available co-solute paramagnetic probes. We then explore how sPRE, in combination with complementary biophysical techniques, can further advance biomolecular structure determination, identification of interaction surfaces within protein complexes, and probing of conformational changes and low-population transient states, as well as deliver insights into weak, nonspecific, and transient interactions between proteins and co-solutes. In addition, we present examples of how the incorporation of solvent paramagnetic probes can improve the sensitivity of NMR experiments and discuss the prospects of applying sPRE to NMR metabolomics, drug discovery, and the study of intrinsically disordered proteins.
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Affiliation(s)
- Aneta J Lenard
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Ageing, Molecular Biology and Biochemistry, Research Unit Integrative Structural Biology, Medical University of Graz, 8010 Graz, Austria.
| | - Frans A A Mulder
- Interdisciplinary Nanoscience Center and Department of Chemistry, University of Aarhus, DK-8000 Aarhus, Denmark; Institute of Biochemistry, Johannes Kepler Universität Linz, 4040 Linz, Austria.
| | - Tobias Madl
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Ageing, Molecular Biology and Biochemistry, Research Unit Integrative Structural Biology, Medical University of Graz, 8010 Graz, Austria; BioTechMed-Graz, 8010 Graz, Austria.
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2
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Miao Q, Nitsche C, Orton H, Overhand M, Otting G, Ubbink M. Paramagnetic Chemical Probes for Studying Biological Macromolecules. Chem Rev 2022; 122:9571-9642. [PMID: 35084831 PMCID: PMC9136935 DOI: 10.1021/acs.chemrev.1c00708] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Indexed: 12/11/2022]
Abstract
Paramagnetic chemical probes have been used in electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) spectroscopy for more than four decades. Recent years witnessed a great increase in the variety of probes for the study of biological macromolecules (proteins, nucleic acids, and oligosaccharides). This Review aims to provide a comprehensive overview of the existing paramagnetic chemical probes, including chemical synthetic approaches, functional properties, and selected applications. Recent developments have seen, in particular, a rapid expansion of the range of lanthanoid probes with anisotropic magnetic susceptibilities for the generation of structural restraints based on residual dipolar couplings and pseudocontact shifts in solution and solid state NMR spectroscopy, mostly for protein studies. Also many new isotropic paramagnetic probes, suitable for NMR measurements of paramagnetic relaxation enhancements, as well as EPR spectroscopic studies (in particular double resonance techniques) have been developed and employed to investigate biological macromolecules. Notwithstanding the large number of reported probes, only few have found broad application and further development of probes for dedicated applications is foreseen.
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Affiliation(s)
- Qing Miao
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, Leiden 2333 CC, The Netherlands
- School
of Chemistry &Chemical Engineering, Shaanxi University of Science & Technology, Xi’an710021, China
| | - Christoph Nitsche
- Research
School of Chemistry, The Australian National
University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
| | - Henry Orton
- Research
School of Chemistry, The Australian National
University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
- ARC
Centre of Excellence for Innovations in Peptide & Protein Science,
Research School of Chemistry, Australian
National University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
| | - Mark Overhand
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, Leiden 2333 CC, The Netherlands
| | - Gottfried Otting
- Research
School of Chemistry, The Australian National
University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
- ARC
Centre of Excellence for Innovations in Peptide & Protein Science,
Research School of Chemistry, Australian
National University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
| | - Marcellus Ubbink
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, Leiden 2333 CC, The Netherlands
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3
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Probing Surfaces in Dynamic Protein Interactions. J Mol Biol 2020; 432:2949-2972. [DOI: 10.1016/j.jmb.2020.02.032] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2019] [Revised: 02/22/2020] [Accepted: 02/24/2020] [Indexed: 01/09/2023]
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Khade PM, Kumar A, Jernigan RL. Characterizing and Predicting Protein Hinges for Mechanistic Insight. J Mol Biol 2019; 432:508-522. [PMID: 31786268 DOI: 10.1016/j.jmb.2019.11.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 11/01/2019] [Accepted: 11/15/2019] [Indexed: 12/21/2022]
Abstract
The functioning of proteins requires highly specific dynamics, which depend critically on the details of how amino acids are packed. Hinge motions are the most common type of large motion, typified by the opening and closing of enzymes around their substrates. The packing and geometries of residues are characterized here by graph theory. This characterization is sufficient to enable reliable hinge predictions from a single static structure, and notably, this can be from either the open or the closed form of a structure. This new method to identify hinges within protein structures is called PACKMAN. The predicted hinges are validated by using permutation tests on B-factors. Hinge prediction results are compared against lists of manually curated hinge residues, and the results suggest that PACKMAN is robust enough to reproduce the known conformational changes and is able to predict hinge regions equally well from either the open or the closed forms of a protein. A group of 167 protein pairs with open and closed structures has been investigated Examples are shown for several additional proteins, including Zika virus nonstructured (NS) proteins where there are 6 hinge regions in the NS5 protein, 5 hinge regions in the NS2B bound in the NS3 protease complex and 5 hinges in the NS3- helicase protein. Results obtained from this method can be important for generating conformational ensembles of protein targets for drug design. PACKMAN is freely accessible at (https://PACKMAN.bb.iastate.edu/).
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Affiliation(s)
- Pranav M Khade
- Bioinformatics and Computational Biology Program, Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA, 50011, USA
| | - Ambuj Kumar
- Bioinformatics and Computational Biology Program, Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA, 50011, USA
| | - Robert L Jernigan
- Bioinformatics and Computational Biology Program, Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA, 50011, USA.
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5
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Hartlmüller C, Spreitzer E, Göbl C, Falsone F, Madl T. NMR characterization of solvent accessibility and transient structure in intrinsically disordered proteins. JOURNAL OF BIOMOLECULAR NMR 2019; 73:305-317. [PMID: 31297688 PMCID: PMC6692294 DOI: 10.1007/s10858-019-00248-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Accepted: 04/11/2019] [Indexed: 05/12/2023]
Abstract
In order to understand the conformational behavior of intrinsically disordered proteins (IDPs) and their biological interaction networks, the detection of residual structure and long-range interactions is required. However, the large number of degrees of conformational freedom of disordered proteins require the integration of extensive sets of experimental data, which are difficult to obtain. Here, we provide a straightforward approach for the detection of residual structure and long-range interactions in IDPs under near-native conditions using solvent paramagnetic relaxation enhancement (sPRE). Our data indicate that for the general case of an unfolded chain, with a local flexibility described by the overwhelming majority of available combinations, sPREs of non-exchangeable protons can be accurately predicted through an ensemble-based fragment approach. We show for the disordered protein α-synuclein and disordered regions of the proteins FOXO4 and p53 that deviation from random coil behavior can be interpreted in terms of intrinsic propensity to populate local structure in interaction sites of these proteins and to adopt transient long-range structure. The presented modification-free approach promises to be applicable to study conformational dynamics of IDPs and other dynamic biomolecules in an integrative approach.
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Affiliation(s)
- Christoph Hartlmüller
- Center for Integrated Protein Science Munich (CIPSM) at the Department of Chemistry, Technische Universität München, Lichtenbergstrasse 4, 87548, Garching, Germany
| | - Emil Spreitzer
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Institute of Molecular Biology & Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6, 8010, Graz, Austria
| | - Christoph Göbl
- The Campbell Family Institute for Breast Cancer Research at Princess Margaret Cancer Centre, 610 University Avenue, Toronto, ON, M5G 2M9, Canada
| | - Fabio Falsone
- Institute of Pharmaceutical Sciences, University of Graz, Schubertstrasse 1, 8010, Graz, Austria
| | - Tobias Madl
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Institute of Molecular Biology & Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6, 8010, Graz, Austria.
- BioTechMed-Graz, Graz, Austria.
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Iwahara J, Zandarashvili L, Kemme CA, Esadze A. NMR-based investigations into target DNA search processes of proteins. Methods 2018; 148:57-66. [PMID: 29753002 DOI: 10.1016/j.ymeth.2018.05.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 05/04/2018] [Indexed: 10/16/2022] Open
Abstract
To perform their function, transcription factors and DNA-repair/modifying enzymes must first locate their targets in the vast presence of nonspecific, but structurally similar sites on genomic DNA. Before reaching their targets, these proteins stochastically scan DNA and dynamically move from one site to another on DNA. Solution NMR spectroscopy provides unique atomic-level insights into the dynamic DNA-scanning processes, which are difficult to gain by any other experimental means. In this review, we provide an introductory overview on the NMR methods for the structural, dynamic, and kinetic investigations of target DNA search by proteins. We also discuss advantages and disadvantages of these NMR methods over other methods such as single-molecule techniques and biochemical approaches.
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Affiliation(s)
- Junji Iwahara
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, United States.
| | - Levani Zandarashvili
- Department of Biochemistry and Biophysics, University of Pennsylvania, United States
| | - Catherine A Kemme
- Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, United States
| | - Alexandre Esadze
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University, United States
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Schulte M, Petrović D, Neudecker P, Hartmann R, Pietruszka J, Willbold S, Willbold D, Panwalkar V. Conformational Sampling of the Intrinsically Disordered C-Terminal Tail of DERA Is Important for Enzyme Catalysis. ACS Catal 2018; 8:3971-3984. [PMID: 30101036 PMCID: PMC6080863 DOI: 10.1021/acscatal.7b04408] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 03/24/2018] [Indexed: 12/13/2022]
Abstract
2-Deoxyribose-5-phosphate aldolase (DERA) catalyzes the reversible conversion of acetaldehyde and glyceraldehyde-3-phosphate into deoxyribose-5-phosphate. DERA is used as a biocatalyst for the synthesis of drugs such as statins and is a promising pharmaceutical target due to its involvement in nucleotide catabolism. Despite previous biochemical studies suggesting the catalytic importance of the C-terminal tyrosine residue found in several bacterial DERAs, the structural and functional basis of its participation in catalysis remains elusive because the electron density for the last eight to nine residues (i.e., the C-terminal tail) is absent in all available crystal structures. Using a combination of NMR spectroscopy and molecular dynamics simulations, we conclusively show that the rarely studied C-terminal tail of E. coli DERA (ecDERA) is intrinsically disordered and exists in equilibrium between open and catalytically relevant closed states, where the C-terminal tyrosine (Y259) enters the active site. Nuclear Overhauser effect distance restraints, obtained due to the presence of a substantial closed state population, were used to derive the solution-state structure of the ecDERA closed state. Real-time NMR hydrogen/deuterium exchange experiments reveal that Y259 is required for efficiency of the proton abstraction step of the catalytic reaction. Phosphate titration experiments show that, in addition to the phosphate-binding residues located near the active site, as observed in the available crystal structures, ecDERA contains previously unknown auxiliary phosphate-binding residues on the C-terminal tail which could facilitate in orienting Y259 in an optimal position for catalysis. Thus, we present significant insights into the structural and mechanistic importance of the ecDERA C-terminal tail and illustrate the role of conformational sampling in enzyme catalysis.
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Affiliation(s)
- Marianne Schulte
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
- Institute of Complex Systems 6 (ICS-6): Structural Biochemistry, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Dušan Petrović
- Institute of Complex Systems 6 (ICS-6): Structural Biochemistry, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Philipp Neudecker
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
- Institute of Complex Systems 6 (ICS-6): Structural Biochemistry, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Rudolf Hartmann
- Institute of Complex Systems 6 (ICS-6): Structural Biochemistry, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Jörg Pietruszka
- Institute of Bioorganic Chemistry, Heinrich-Heine-Universität im Forschungszentrum Jülich, 52425 Jülich, Germany
- Institute of Bio- and Geosciences 1 (IBG-1): Biotechnology, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Sabine Willbold
- Central Institute of Engineering, Electronics and Analytics (ZEA-3), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Dieter Willbold
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
- Institute of Complex Systems 6 (ICS-6): Structural Biochemistry, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Vineet Panwalkar
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
- Institute of Complex Systems 6 (ICS-6): Structural Biochemistry, Forschungszentrum Jülich, 52425 Jülich, Germany
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8
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Hartlmüller C, Göbl C, Madl T. Prediction of Protein Structure Using Surface Accessibility Data. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201604788] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Christoph Hartlmüller
- Center for Integrated Protein Science Munich Technische Universität München Department of Chemistry Lichtenbergstrasse 4 85748 Garching Germany
- Institute of Structural Biology Helmholtz Zentrum München Ingolstädter Landstrasse 1 85764 Neuherberg Germany
| | - Christoph Göbl
- Center for Integrated Protein Science Munich Technische Universität München Department of Chemistry Lichtenbergstrasse 4 85748 Garching Germany
- Institute of Structural Biology Helmholtz Zentrum München Ingolstädter Landstrasse 1 85764 Neuherberg Germany
| | - Tobias Madl
- Center for Integrated Protein Science Munich Technische Universität München Department of Chemistry Lichtenbergstrasse 4 85748 Garching Germany
- Institute of Structural Biology Helmholtz Zentrum München Ingolstädter Landstrasse 1 85764 Neuherberg Germany
- Institute of Molecular Biology & Biochemistry Center of Molecular Medicine Medical University of Graz 8010 Graz Austria
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9
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Hartlmüller C, Göbl C, Madl T. Prediction of Protein Structure Using Surface Accessibility Data. Angew Chem Int Ed Engl 2016; 55:11970-4. [PMID: 27560616 PMCID: PMC5026166 DOI: 10.1002/anie.201604788] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 07/12/2016] [Indexed: 11/06/2022]
Abstract
An approach to the de novo structure prediction of proteins is described that relies on surface accessibility data from NMR paramagnetic relaxation enhancements by a soluble paramagnetic compound (sPRE). This method exploits the distance-to-surface information encoded in the sPRE data in the chemical shift-based CS-Rosetta de novo structure prediction framework to generate reliable structural models. For several proteins, it is demonstrated that surface accessibility data is an excellent measure of the correct protein fold in the early stages of the computational folding algorithm and significantly improves accuracy and convergence of the standard Rosetta structure prediction approach.
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Affiliation(s)
- Christoph Hartlmüller
- Center for Integrated Protein Science Munich, Technische Universität München, Department of Chemistry, Lichtenbergstrasse 4, 85748, Garching, Germany.,Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764, Neuherberg, Germany
| | - Christoph Göbl
- Center for Integrated Protein Science Munich, Technische Universität München, Department of Chemistry, Lichtenbergstrasse 4, 85748, Garching, Germany.,Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764, Neuherberg, Germany
| | - Tobias Madl
- Center for Integrated Protein Science Munich, Technische Universität München, Department of Chemistry, Lichtenbergstrasse 4, 85748, Garching, Germany. .,Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764, Neuherberg, Germany. .,Institute of Molecular Biology & Biochemistry, Center of Molecular Medicine, Medical University of Graz, 8010, Graz, Austria.
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10
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Göbl C, Madl T, Simon B, Sattler M. NMR approaches for structural analysis of multidomain proteins and complexes in solution. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2014; 80:26-63. [PMID: 24924266 DOI: 10.1016/j.pnmrs.2014.05.003] [Citation(s) in RCA: 130] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 05/14/2014] [Indexed: 05/22/2023]
Abstract
NMR spectroscopy is a key method for studying the structure and dynamics of (large) multidomain proteins and complexes in solution. It plays a unique role in integrated structural biology approaches as especially information about conformational dynamics can be readily obtained at residue resolution. Here, we review NMR techniques for such studies focusing on state-of-the-art tools and practical aspects. An efficient approach for determining the quaternary structure of multidomain complexes starts from the structures of individual domains or subunits. The arrangement of the domains/subunits within the complex is then defined based on NMR measurements that provide information about the domain interfaces combined with (long-range) distance and orientational restraints. Aspects discussed include sample preparation, specific isotope labeling and spin labeling; determination of binding interfaces and domain/subunit arrangements from chemical shift perturbations (CSP), nuclear Overhauser effects (NOEs), isotope editing/filtering, cross-saturation, and differential line broadening; and based on paramagnetic relaxation enhancements (PRE) using covalent and soluble spin labels. Finally, the utility of complementary methods such as small-angle X-ray or neutron scattering (SAXS, SANS), electron paramagnetic resonance (EPR) or fluorescence spectroscopy techniques is discussed. The applications of NMR techniques are illustrated with studies of challenging (high molecular weight) protein complexes.
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Affiliation(s)
- Christoph Göbl
- Biomolecular NMR and Center for Integrated Protein Science Munich at Department Chemie, Technische Universität München, Garching, Germany
| | - Tobias Madl
- Biomolecular NMR and Center for Integrated Protein Science Munich at Department Chemie, Technische Universität München, Garching, Germany; Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany; Institute of Molecular Biology, University of Graz, Graz, Austria.
| | - Bernd Simon
- European Molecular Biology Laboratory, Structural and Computational Biology Unit, Meyerhofstraße 1, 69117 Heidelberg, Germany
| | - Michael Sattler
- Biomolecular NMR and Center for Integrated Protein Science Munich at Department Chemie, Technische Universität München, Garching, Germany; Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany.
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11
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Duplex interrogation by a direct DNA repair protein in search of base damage. Nat Struct Mol Biol 2012; 19:671-6. [PMID: 22659876 PMCID: PMC3392526 DOI: 10.1038/nsmb.2320] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 04/30/2012] [Indexed: 12/04/2022]
Abstract
ALKBH2 is a direct DNA repair dioxygenase guarding mammalian genome against N1-methyladenine, N3-methylcytosine, and 1,N6-ethenoadenine damage. A prerequisite for repair is to identify these lesions in the genome. Here we present crystal structures of ALKBH2 bound to different duplex DNAs. Together with computational and biochemical analyses, our results suggest that DNA interrogation by ALKBH2 displays two novel features: i) ALKBH2 probes base-pair stability and detects base pairs with reduced stability; ii) ALKBH2 does not have nor need a “damage-checking site”, which is critical for preventing spurious base-cleavage for several glycosylases. The demethylation mechanism of ALKBH2 insures that only cognate lesions are oxidized and reversed to normal bases, and that a flipped, non-substrate base remains intact in the active site. Overall, the combination of duplex interrogation and oxidation chemistry allows ALKBH2 to detect and process diverse lesions efficiently and correctly.
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12
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Berlow RB, Swain M, Dalal S, Sweasy JB, Loria JP. Substrate-dependent millisecond domain motions in DNA polymerase β. J Mol Biol 2012; 419:171-82. [PMID: 22446382 DOI: 10.1016/j.jmb.2012.03.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 03/12/2012] [Accepted: 03/13/2012] [Indexed: 02/02/2023]
Abstract
DNA polymerase β (Pol β) is a 39-kDa enzyme that performs the vital cellular function of repairing damaged DNA. Mutations in Pol β have been linked to various cancers, and these mutations are further correlated with altered Pol β enzymatic activity. The fidelity of correct nucleotide incorporation into damaged DNA is essential for Pol β repair function, and several studies have implicated conformational changes in Pol β as a determinant of this repair fidelity. In this work, the rate constants for domain motions in Pol β have been determined by solution NMR relaxation dispersion for the apo and substrate-bound, binary forms of Pol β. In apo Pol β, molecular motions, primarily isolated to the DNA lyase domain, are observed to occur at 1400 s(-1). Additional analysis suggests that these motions allow apo Pol β to sample a conformation similar to the gapped DNA-substrate-bound form. Upon binding DNA, these lyase domain motions are significantly quenched, whereas evidence for conformational motions in the polymerase domain becomes apparent. These NMR studies suggest an alteration in the dynamic landscape of Pol β due to substrate binding. Moreover, a number of the flexible residues identified in this work are also the location of residues, which upon mutation lead to cancer phenotypes in vivo, which may be due to the intimate role of protein motions in Pol β fidelity.
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Affiliation(s)
- Rebecca B Berlow
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
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