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Funk LM, Poschmann G, Rabe von Pappenheim F, Chari A, Stegmann KM, Dickmanns A, Wensien M, Eulig N, Paknia E, Heyne G, Penka E, Pearson AR, Berndt C, Fritz T, Bazzi S, Uranga J, Mata RA, Dobbelstein M, Hilgenfeld R, Curth U, Tittmann K. Multiple redox switches of the SARS-CoV-2 main protease in vitro provide opportunities for drug design. Nat Commun 2024; 15:411. [PMID: 38195625 PMCID: PMC10776599 DOI: 10.1038/s41467-023-44621-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Accepted: 12/21/2023] [Indexed: 01/11/2024] Open
Abstract
Besides vaccines, the development of antiviral drugs targeting SARS-CoV-2 is critical for preventing future COVID outbreaks. The SARS-CoV-2 main protease (Mpro), a cysteine protease with essential functions in viral replication, has been validated as an effective drug target. Here, we show that Mpro is subject to redox regulation in vitro and reversibly switches between the enzymatically active dimer and the functionally dormant monomer through redox modifications of cysteine residues. These include a disulfide-dithiol switch between the catalytic cysteine C145 and cysteine C117, and generation of an allosteric cysteine-lysine-cysteine SONOS bridge that is required for structural stability under oxidative stress conditions, such as those exerted by the innate immune system. We identify homo- and heterobifunctional reagents that mimic the redox switching and inhibit Mpro activity. The discovered redox switches are conserved in main proteases from other coronaviruses, e.g. MERS-CoV and SARS-CoV, indicating their potential as common druggable sites.
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Affiliation(s)
- Lisa-Marie Funk
- Department of Molecular Enzymology, Göttingen Center of Molecular Biosciences, Georg-August University Göttingen, Julia-Lermontowa-Weg 3, D-37077, Göttingen, Germany
- Max-Planck-Institute for Multidisciplinary Sciences, Am Fassberg 11, D-37077, Göttingen, Germany
| | - Gereon Poschmann
- Institute of Molecular Medicine, Proteome Research, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine University Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Fabian Rabe von Pappenheim
- Department of Molecular Enzymology, Göttingen Center of Molecular Biosciences, Georg-August University Göttingen, Julia-Lermontowa-Weg 3, D-37077, Göttingen, Germany
- Max-Planck-Institute for Multidisciplinary Sciences, Am Fassberg 11, D-37077, Göttingen, Germany
| | - Ashwin Chari
- Department of Structural Dynamics, Max-Planck-Institute for Multidisciplinary Sciences, Am Fassberg 11, D-37077, Göttingen, Germany
| | - Kim M Stegmann
- Institute of Molecular Oncology, University Medical Center Göttingen, Justus-von-Liebig-Weg 11, 37077, Göttingen, Germany
| | - Antje Dickmanns
- Institute of Molecular Oncology, University Medical Center Göttingen, Justus-von-Liebig-Weg 11, 37077, Göttingen, Germany
| | - Marie Wensien
- Department of Molecular Enzymology, Göttingen Center of Molecular Biosciences, Georg-August University Göttingen, Julia-Lermontowa-Weg 3, D-37077, Göttingen, Germany
- Max-Planck-Institute for Multidisciplinary Sciences, Am Fassberg 11, D-37077, Göttingen, Germany
| | - Nora Eulig
- Department of Molecular Enzymology, Göttingen Center of Molecular Biosciences, Georg-August University Göttingen, Julia-Lermontowa-Weg 3, D-37077, Göttingen, Germany
- Max-Planck-Institute for Multidisciplinary Sciences, Am Fassberg 11, D-37077, Göttingen, Germany
| | - Elham Paknia
- Department of Structural Dynamics, Max-Planck-Institute for Multidisciplinary Sciences, Am Fassberg 11, D-37077, Göttingen, Germany
| | - Gabi Heyne
- Department of Structural Dynamics, Max-Planck-Institute for Multidisciplinary Sciences, Am Fassberg 11, D-37077, Göttingen, Germany
| | - Elke Penka
- Department of Molecular Enzymology, Göttingen Center of Molecular Biosciences, Georg-August University Göttingen, Julia-Lermontowa-Weg 3, D-37077, Göttingen, Germany
- Max-Planck-Institute for Multidisciplinary Sciences, Am Fassberg 11, D-37077, Göttingen, Germany
| | - Arwen R Pearson
- Institute for Nanostructure and Solid-State Physics, Hamburg Centre for Ultrafast Imaging, Hamburg University, HARBOR, Luruper Chaussee 149, Hamburg, 22761, Germany
| | - Carsten Berndt
- Department of Neurology, Medical Faculty, Heinrich-Heine University Düsseldorf, Moorenstr. 5, 40225, Düsseldorf, Germany
| | - Tobias Fritz
- Institute of Physical Chemistry, Georg-August University Göttingen, Tammannstraße 6, D-37077, Göttingen, Germany
| | - Sophia Bazzi
- Institute of Physical Chemistry, Georg-August University Göttingen, Tammannstraße 6, D-37077, Göttingen, Germany
| | - Jon Uranga
- Institute of Physical Chemistry, Georg-August University Göttingen, Tammannstraße 6, D-37077, Göttingen, Germany
| | - Ricardo A Mata
- Institute of Physical Chemistry, Georg-August University Göttingen, Tammannstraße 6, D-37077, Göttingen, Germany
| | - Matthias Dobbelstein
- Institute of Molecular Oncology, University Medical Center Göttingen, Justus-von-Liebig-Weg 11, 37077, Göttingen, Germany
| | - Rolf Hilgenfeld
- Institute for Biochemistry, Lübeck University, Ratzeburger Allee 160, 23562, Lübeck, Germany
- German Center for Infection Research, Hamburg - Lübeck-Borstel-Riems Site, University of Lübeck, Ratzeburger Allee 160, 23562, Lübeck, Germany
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany
| | - Kai Tittmann
- Department of Molecular Enzymology, Göttingen Center of Molecular Biosciences, Georg-August University Göttingen, Julia-Lermontowa-Weg 3, D-37077, Göttingen, Germany.
- Max-Planck-Institute for Multidisciplinary Sciences, Am Fassberg 11, D-37077, Göttingen, Germany.
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Oleshko O, Vollack-Hesse N, Tiede A, Hegermann J, Curth U, Werwitzke S. von Willebrand factor modulates immune complexes and the recall response against factor VIII in a murine hemophilia A model. Blood Adv 2023; 7:6771-6781. [PMID: 37756521 PMCID: PMC10660012 DOI: 10.1182/bloodadvances.2023010388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 09/13/2023] [Accepted: 09/16/2023] [Indexed: 09/29/2023] Open
Abstract
Achieving tolerance toward factor VIII (FVIII) remains an important goal of hemophilia treatment. Up to 40% of patients with severe hemophilia A (HA) develop neutralizing antibodies against FVIII, and the only proven treatment to achieve tolerance is infusion of FVIII over prolonged periods in the context of immune tolerance induction. Here, we addressed the role of von Willebrand factor (VWF) as a modulator of anti-FVIII antibody effector functions and the FVIII-specific recall response in an HA mouse model. Analytical ultracentrifugation was used to demonstrate formation of FVIII-containing immune complexes (FVIII-ICs). VWF did not fully prevent FVIII-IC formation but was rather incorporated into larger macromolecular complexes. VWF prevented binding of FVIII-ICs to complement C1q, most efficiently when it was preincubated with FVIII before the addition of antibodies. It also prevented binding to immobilized Fc-γ receptor and to bone marrow-derived dendritic cells. An in vitro model of the anti-FVIII recall response demonstrated that addition of VWF to FVIII abolished the proliferation of FVIII-specific antibody-secreting cells. After adoptive transfer of sensitized splenocytes into immunocompetent HA mice, the FVIII recall response was diminished by VWF. In summary, these data indicate that VWF modulates the formation and effector functions of FVIII-ICs and attenuates the secondary immune response to FVIII in HA mice.
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Affiliation(s)
- Olga Oleshko
- Department of Hematology, Hemostasis, Oncology and Stem Cell Transplantation, Hannover Medical School, Hannover, Germany
| | - Nadine Vollack-Hesse
- Department of Hematology, Hemostasis, Oncology and Stem Cell Transplantation, Hannover Medical School, Hannover, Germany
| | - Andreas Tiede
- Department of Hematology, Hemostasis, Oncology and Stem Cell Transplantation, Hannover Medical School, Hannover, Germany
| | - Jan Hegermann
- Research Core Unit Electron Microscopy, Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Sonja Werwitzke
- Department of Hematology, Hemostasis, Oncology and Stem Cell Transplantation, Hannover Medical School, Hannover, Germany
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3
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Naniima P, Naimo E, Koch S, Curth U, Alkharsah KR, Ströh LJ, Binz A, Beneke JM, Vollmer B, Böning H, Borst EM, Desai P, Bohne J, Messerle M, Bauerfeind R, Legrand P, Sodeik B, Schulz TF, Krey T. Assembly of infectious Kaposi's sarcoma-associated herpesvirus progeny requires formation of a pORF19 pentamer. PLoS Biol 2021; 19:e3001423. [PMID: 34735435 PMCID: PMC8568140 DOI: 10.1371/journal.pbio.3001423] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 09/22/2021] [Indexed: 12/25/2022] Open
Abstract
Herpesviruses cause severe diseases particularly in immunocompromised patients. Both genome packaging and release from the capsid require a unique portal channel occupying one of the 12 capsid vertices. Here, we report the 2.6 Å crystal structure of the pentameric pORF19 of the γ-herpesvirus Kaposi’s sarcoma-associated herpesvirus (KSHV) resembling the portal cap that seals this portal channel. We also present the structure of its β-herpesviral ortholog, revealing a striking structural similarity to its α- and γ-herpesviral counterparts despite apparent differences in capsid association. We demonstrate pORF19 pentamer formation in solution and provide insights into how pentamerization is triggered in infected cells. Mutagenesis in its lateral interfaces blocked pORF19 pentamerization and severely affected KSHV capsid assembly and production of infectious progeny. Our results pave the way to better understand the role of pORF19 in capsid assembly and identify a potential novel drug target for the treatment of herpesvirus-induced diseases. In herpesviruses, genome packaging and release from the capsid require a unique portal channel. Here, the authors have resolved the crystal structure of a pentameric KSHV pORF19 assembly and find that it resembles the herpesviral portal cap and provides insights how the viral genome is retained within the capsid.
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Affiliation(s)
- Peter Naniima
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Center for Infection Research (DZIF), partner sites Hannover-Braunschweig and Hamburg-Lübeck-Borstel-Riems, Braunschweig, Germany
| | - Eleonora Naimo
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Center for Infection Research (DZIF), partner sites Hannover-Braunschweig and Hamburg-Lübeck-Borstel-Riems, Braunschweig, Germany
| | - Sandra Koch
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Center for Infection Research (DZIF), partner sites Hannover-Braunschweig and Hamburg-Lübeck-Borstel-Riems, Braunschweig, Germany
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Khaled R. Alkharsah
- Department of Microbiology, College of Medicine, Imam Abdulrahman Bin Faisal University (IAU), Dammam, Saudi Arabia
| | - Luisa J. Ströh
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Anne Binz
- Institute of Virology, Hannover Medical School, Hannover, Germany
- Excellence Cluster 2155 RESIST, Hannover Medical School, Hannover, Germany
| | - Jan-Marc Beneke
- Center of Structural and Cell Biology in Medicine, Institute of Biochemistry, University of Luebeck, Luebeck, Germany
| | - Benjamin Vollmer
- Centre for Structural Systems Biology, Leibniz-Institut für Experimentelle Virologie (HPI), Hamburg, Germany
| | - Heike Böning
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Eva Maria Borst
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Prashant Desai
- Department of Oncology, The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, The Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Jens Bohne
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Martin Messerle
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Center for Infection Research (DZIF), partner sites Hannover-Braunschweig and Hamburg-Lübeck-Borstel-Riems, Braunschweig, Germany
- Excellence Cluster 2155 RESIST, Hannover Medical School, Hannover, Germany
| | - Rudolf Bauerfeind
- Research Core Unit Laser Microscopy, Hannover Medical School, Hannover, Germany
| | - Pierre Legrand
- Synchrotron SOLEIL, L’Orme des Merisiers, Gif-sur-Yvette, France
| | - Beate Sodeik
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Center for Infection Research (DZIF), partner sites Hannover-Braunschweig and Hamburg-Lübeck-Borstel-Riems, Braunschweig, Germany
- Excellence Cluster 2155 RESIST, Hannover Medical School, Hannover, Germany
| | - Thomas F. Schulz
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Center for Infection Research (DZIF), partner sites Hannover-Braunschweig and Hamburg-Lübeck-Borstel-Riems, Braunschweig, Germany
- Excellence Cluster 2155 RESIST, Hannover Medical School, Hannover, Germany
| | - Thomas Krey
- Institute of Virology, Hannover Medical School, Hannover, Germany
- German Center for Infection Research (DZIF), partner sites Hannover-Braunschweig and Hamburg-Lübeck-Borstel-Riems, Braunschweig, Germany
- Excellence Cluster 2155 RESIST, Hannover Medical School, Hannover, Germany
- Center of Structural and Cell Biology in Medicine, Institute of Biochemistry, University of Luebeck, Luebeck, Germany
- Centre for Structural Systems Biology (CSSB), Hamburg, Germany
- * E-mail:
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Rai A, Klare JP, Reinke PYA, Englmaier F, Fohrer J, Fedorov R, Taft MH, Chizhov I, Curth U, Plettenburg O, Manstein DJ. Structural and Biochemical Characterization of a Dye-Decolorizing Peroxidase from Dictyostelium discoideum. Int J Mol Sci 2021; 22:ijms22126265. [PMID: 34200865 PMCID: PMC8230527 DOI: 10.3390/ijms22126265] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 05/29/2021] [Accepted: 06/05/2021] [Indexed: 12/23/2022] Open
Abstract
A novel cytoplasmic dye-decolorizing peroxidase from Dictyostelium discoideum was investigated that oxidizes anthraquinone dyes, lignin model compounds, and general peroxidase substrates such as ABTS efficiently. Unlike related enzymes, an aspartate residue replaces the first glycine of the conserved GXXDG motif in Dictyostelium DyPA. In solution, Dictyostelium DyPA exists as a stable dimer with the side chain of Asp146 contributing to the stabilization of the dimer interface by extending the hydrogen bond network connecting two monomers. To gain mechanistic insights, we solved the Dictyostelium DyPA structures in the absence of substrate as well as in the presence of potassium cyanide and veratryl alcohol to 1.7, 1.85, and 1.6 Å resolution, respectively. The active site of Dictyostelium DyPA has a hexa-coordinated heme iron with a histidine residue at the proximal axial position and either an activated oxygen or CN- molecule at the distal axial position. Asp149 is in an optimal conformation to accept a proton from H2O2 during the formation of compound I. Two potential distal solvent channels and a conserved shallow pocket leading to the heme molecule were found in Dictyostelium DyPA. Further, we identified two substrate-binding pockets per monomer in Dictyostelium DyPA at the dimer interface. Long-range electron transfer pathways associated with a hydrogen-bonding network that connects the substrate-binding sites with the heme moiety are described.
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Affiliation(s)
- Amrita Rai
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for Medical Research Carl Neuberg Str. 1, D-30625 Hannover, Germany; (A.R.); (P.Y.A.R.); (M.H.T.); (I.C.); (U.C.)
- Department of Structural Biochemistry, Max Planck Institute of Molecular Physiology, D-44227 Dortmund, Germany
| | - Johann P. Klare
- Department of Physics, University of Osnabrueck, Barbarastrasse 7, D-49076 Osnabrück, Germany;
| | - Patrick Y. A. Reinke
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for Medical Research Carl Neuberg Str. 1, D-30625 Hannover, Germany; (A.R.); (P.Y.A.R.); (M.H.T.); (I.C.); (U.C.)
- Division for Structural Biochemistry, Hannover Medical School, Carl Neuberg Str. 1, D-30625 Hannover, Germany;
- Center for Free-Electron Laser Science, German Electron Synchrotron (DESY), Notkestr. 85, D-22607 Hamburg, Germany
| | - Felix Englmaier
- Institute of Medicinal Chemistry, Helmholtz Zentrum München (GmbH), German Research Center for Environmental Health, Ingolstädter Landstraße 1, D-85764 Neuherberg, Germany; (F.E.); (O.P.)
- Center of Biomolecular Drug Research (BMWZ), Institute of Organic Chemistry, Leibniz University Hannover, Schneiderberg 1b, D-30167 Hannover, Germany;
| | - Jörg Fohrer
- Center of Biomolecular Drug Research (BMWZ), Institute of Organic Chemistry, Leibniz University Hannover, Schneiderberg 1b, D-30167 Hannover, Germany;
- NMR Department of the Department of Chemistry, Technical University Darmstadt, Clemens Schöpf Institute for Organic Chemistry and Biochemistry, Alarich-Weiss-Strasse 4, D-64287 Darmstadt, Germany
| | - Roman Fedorov
- Division for Structural Biochemistry, Hannover Medical School, Carl Neuberg Str. 1, D-30625 Hannover, Germany;
| | - Manuel H. Taft
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for Medical Research Carl Neuberg Str. 1, D-30625 Hannover, Germany; (A.R.); (P.Y.A.R.); (M.H.T.); (I.C.); (U.C.)
| | - Igor Chizhov
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for Medical Research Carl Neuberg Str. 1, D-30625 Hannover, Germany; (A.R.); (P.Y.A.R.); (M.H.T.); (I.C.); (U.C.)
- Division for Structural Biochemistry, Hannover Medical School, Carl Neuberg Str. 1, D-30625 Hannover, Germany;
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for Medical Research Carl Neuberg Str. 1, D-30625 Hannover, Germany; (A.R.); (P.Y.A.R.); (M.H.T.); (I.C.); (U.C.)
- Division for Structural Biochemistry, Hannover Medical School, Carl Neuberg Str. 1, D-30625 Hannover, Germany;
| | - Oliver Plettenburg
- Institute of Medicinal Chemistry, Helmholtz Zentrum München (GmbH), German Research Center for Environmental Health, Ingolstädter Landstraße 1, D-85764 Neuherberg, Germany; (F.E.); (O.P.)
- Center of Biomolecular Drug Research (BMWZ), Institute of Organic Chemistry, Leibniz University Hannover, Schneiderberg 1b, D-30167 Hannover, Germany;
| | - Dietmar J. Manstein
- Institute for Biophysical Chemistry, Hannover Medical School, Fritz Hartmann Centre for Medical Research Carl Neuberg Str. 1, D-30625 Hannover, Germany; (A.R.); (P.Y.A.R.); (M.H.T.); (I.C.); (U.C.)
- Division for Structural Biochemistry, Hannover Medical School, Carl Neuberg Str. 1, D-30625 Hannover, Germany;
- RESiST, Cluster of Excellence 2155, Medizinische Hochschule Hannover, D-30625 Hannover, Germany
- Correspondence: ; Tel.: +49-511-5323700
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Bogutzki A, Curth U. Analytical Ultracentrifugation for Analysis of Protein-Nucleic Acid Interactions. Methods Mol Biol 2021; 2263:397-421. [PMID: 33877610 DOI: 10.1007/978-1-0716-1197-5_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Analytical ultracentrifugation is a powerful tool to characterize interactions of macromolecules in solution. In sedimentation velocity experiments, the sedimentation of interaction partners and complexes can be monitored directly and can be used to characterize interactions quantitatively. As an example, we show how the interaction of the clamp loader subcomplex of DNA polymerase III from E. coli and a template/primer DNA saturated with single-stranded DNA-binding protein can be analyzed by analytical ultracentrifugation with fluorescence detection.
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Affiliation(s)
- Andrea Bogutzki
- Hannover Medical School, Institute for Biophysical Chemistry, Hannover, Germany
| | - Ute Curth
- Hannover Medical School, Institute for Biophysical Chemistry, Hannover, Germany.
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Fiebig T, Cramer JT, Bethe A, Baruch P, Curth U, Führing JI, Buettner FFR, Vogel U, Schubert M, Fedorov R, Mühlenhoff M. Structural and mechanistic basis of capsule O-acetylation in Neisseria meningitidis serogroup A. Nat Commun 2020; 11:4723. [PMID: 32948778 PMCID: PMC7501274 DOI: 10.1038/s41467-020-18464-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 08/20/2020] [Indexed: 02/08/2023] Open
Abstract
O-Acetylation of the capsular polysaccharide (CPS) of Neisseria meningitidis serogroup A (NmA) is critical for the induction of functional immune responses, making this modification mandatory for CPS-based anti-NmA vaccines. Using comprehensive NMR studies, we demonstrate that O-acetylation stabilizes the labile anomeric phosphodiester-linkages of the NmA-CPS and occurs in position C3 and C4 of the N-acetylmannosamine units due to enzymatic transfer and non-enzymatic ester migration, respectively. To shed light on the enzymatic transfer mechanism, we solved the crystal structure of the capsule O-acetyltransferase CsaC in its apo and acceptor-bound form and of the CsaC-H228A mutant as trapped acetyl-enzyme adduct in complex with CoA. Together with the results of a comprehensive mutagenesis study, the reported structures explain the strict regioselectivity of CsaC and provide insight into the catalytic mechanism, which relies on an unexpected Gln-extension of a classical Ser-His-Asp triad, embedded in an α/β-hydrolase fold.
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Affiliation(s)
- Timm Fiebig
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany.
| | | | - Andrea Bethe
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Petra Baruch
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Jana I Führing
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
- Fraunhofer International Consortium for Anti-Infective Research (iCAIR), Hannover, Germany
| | - Falk F R Buettner
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Ulrich Vogel
- Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
| | - Mario Schubert
- Department of Biosciences, University of Salzburg, Salzburg, Austria
| | - Roman Fedorov
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Martina Mühlenhoff
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany.
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7
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Zhang L, Lin D, Sun X, Curth U, Drosten C, Sauerhering L, Becker S, Rox K, Hilgenfeld R. Crystal structure of SARS-CoV-2 main protease provides a basis for design of improved α-ketoamide inhibitors. Science 2020. [PMID: 32198291 DOI: 10.1038/s41586-020-2223] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) is a global health emergency. An attractive drug target among coronaviruses is the main protease (Mpro, also called 3CLpro) because of its essential role in processing the polyproteins that are translated from the viral RNA. We report the x-ray structures of the unliganded SARS-CoV-2 Mpro and its complex with an α-ketoamide inhibitor. This was derived from a previously designed inhibitor but with the P3-P2 amide bond incorporated into a pyridone ring to enhance the half-life of the compound in plasma. On the basis of the unliganded structure, we developed the lead compound into a potent inhibitor of the SARS-CoV-2 Mpro The pharmacokinetic characterization of the optimized inhibitor reveals a pronounced lung tropism and suitability for administration by the inhalative route.
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Affiliation(s)
- Linlin Zhang
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, 23562 Lübeck, Germany
- German Center for Infection Research (DZIF), Hamburg-Lübeck-Borstel-Riems Site, University of Lübeck, 23562 Lübeck, Germany
| | - Daizong Lin
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, 23562 Lübeck, Germany
- Changchun Discovery Sciences Ltd., 789 Shunda Road, Changchun, Jilin 130012, China
| | - Xinyuanyuan Sun
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, 23562 Lübeck, Germany
- German Center for Infection Research (DZIF), Hamburg-Lübeck-Borstel-Riems Site, University of Lübeck, 23562 Lübeck, Germany
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Christian Drosten
- Institute of Virology, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Lucie Sauerhering
- Institute of Virology, University of Marburg, 35043 Marburg, Germany
- German Center for Infection Research (DZIF), Marburg-Gießen-Langen Site, University of Marburg, 35043 Marburg, Germany
| | - Stephan Becker
- Institute of Virology, University of Marburg, 35043 Marburg, Germany
- German Center for Infection Research (DZIF), Marburg-Gießen-Langen Site, University of Marburg, 35043 Marburg, Germany
| | - Katharina Rox
- Department of Chemical Biology, Helmholtz Center for Infection Research (HZI), 38124 Braunschweig, Germany
- German Center for Infection Research (DZIF), Hannover-Braunschweig Site, Helmholtz Center for Infection Research, 38124 Braunschweig, Germany
| | - Rolf Hilgenfeld
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, 23562 Lübeck, Germany.
- German Center for Infection Research (DZIF), Hamburg-Lübeck-Borstel-Riems Site, University of Lübeck, 23562 Lübeck, Germany
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Zhang L, Lin D, Sun X, Curth U, Drosten C, Sauerhering L, Becker S, Rox K, Hilgenfeld R. Crystal structure of SARS-CoV-2 main protease provides a basis for design of improved α-ketoamide inhibitors. Science 2020. [PMID: 32198291 DOI: 10.1126/science:abb3405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) is a global health emergency. An attractive drug target among coronaviruses is the main protease (Mpro, also called 3CLpro) because of its essential role in processing the polyproteins that are translated from the viral RNA. We report the x-ray structures of the unliganded SARS-CoV-2 Mpro and its complex with an α-ketoamide inhibitor. This was derived from a previously designed inhibitor but with the P3-P2 amide bond incorporated into a pyridone ring to enhance the half-life of the compound in plasma. On the basis of the unliganded structure, we developed the lead compound into a potent inhibitor of the SARS-CoV-2 Mpro The pharmacokinetic characterization of the optimized inhibitor reveals a pronounced lung tropism and suitability for administration by the inhalative route.
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Affiliation(s)
- Linlin Zhang
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, 23562 Lübeck, Germany
- German Center for Infection Research (DZIF), Hamburg-Lübeck-Borstel-Riems Site, University of Lübeck, 23562 Lübeck, Germany
| | - Daizong Lin
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, 23562 Lübeck, Germany
- Changchun Discovery Sciences Ltd., 789 Shunda Road, Changchun, Jilin 130012, China
| | - Xinyuanyuan Sun
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, 23562 Lübeck, Germany
- German Center for Infection Research (DZIF), Hamburg-Lübeck-Borstel-Riems Site, University of Lübeck, 23562 Lübeck, Germany
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Christian Drosten
- Institute of Virology, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Lucie Sauerhering
- Institute of Virology, University of Marburg, 35043 Marburg, Germany
- German Center for Infection Research (DZIF), Marburg-Gießen-Langen Site, University of Marburg, 35043 Marburg, Germany
| | - Stephan Becker
- Institute of Virology, University of Marburg, 35043 Marburg, Germany
- German Center for Infection Research (DZIF), Marburg-Gießen-Langen Site, University of Marburg, 35043 Marburg, Germany
| | - Katharina Rox
- Department of Chemical Biology, Helmholtz Center for Infection Research (HZI), 38124 Braunschweig, Germany
- German Center for Infection Research (DZIF), Hannover-Braunschweig Site, Helmholtz Center for Infection Research, 38124 Braunschweig, Germany
| | - Rolf Hilgenfeld
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, 23562 Lübeck, Germany.
- German Center for Infection Research (DZIF), Hamburg-Lübeck-Borstel-Riems Site, University of Lübeck, 23562 Lübeck, Germany
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9
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Zhang L, Lin D, Sun X, Curth U, Drosten C, Sauerhering L, Becker S, Rox K, Hilgenfeld R. Crystal structure of SARS-CoV-2 main protease provides a basis for design of improved α-ketoamide inhibitors. Science 2020; 368:409-412. [PMID: 32198291 PMCID: PMC7164518 DOI: 10.1126/science.abb3405] [Citation(s) in RCA: 2054] [Impact Index Per Article: 513.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 03/18/2020] [Indexed: 12/12/2022]
Abstract
The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) is a global health emergency. An attractive drug target among coronaviruses is the main protease (Mpro, also called 3CLpro) because of its essential role in processing the polyproteins that are translated from the viral RNA. We report the x-ray structures of the unliganded SARS-CoV-2 Mpro and its complex with an α-ketoamide inhibitor. This was derived from a previously designed inhibitor but with the P3-P2 amide bond incorporated into a pyridone ring to enhance the half-life of the compound in plasma. On the basis of the unliganded structure, we developed the lead compound into a potent inhibitor of the SARS-CoV-2 Mpro The pharmacokinetic characterization of the optimized inhibitor reveals a pronounced lung tropism and suitability for administration by the inhalative route.
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Affiliation(s)
- Linlin Zhang
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, 23562 Lübeck, Germany
- German Center for Infection Research (DZIF), Hamburg-Lübeck-Borstel-Riems Site, University of Lübeck, 23562 Lübeck, Germany
| | - Daizong Lin
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, 23562 Lübeck, Germany
- Changchun Discovery Sciences Ltd., 789 Shunda Road, Changchun, Jilin 130012, China
| | - Xinyuanyuan Sun
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, 23562 Lübeck, Germany
- German Center for Infection Research (DZIF), Hamburg-Lübeck-Borstel-Riems Site, University of Lübeck, 23562 Lübeck, Germany
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Christian Drosten
- Institute of Virology, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Lucie Sauerhering
- Institute of Virology, University of Marburg, 35043 Marburg, Germany
- German Center for Infection Research (DZIF), Marburg-Gießen-Langen Site, University of Marburg, 35043 Marburg, Germany
| | - Stephan Becker
- Institute of Virology, University of Marburg, 35043 Marburg, Germany
- German Center for Infection Research (DZIF), Marburg-Gießen-Langen Site, University of Marburg, 35043 Marburg, Germany
| | - Katharina Rox
- Department of Chemical Biology, Helmholtz Center for Infection Research (HZI), 38124 Braunschweig, Germany
- German Center for Infection Research (DZIF), Hannover-Braunschweig Site, Helmholtz Center for Infection Research, 38124 Braunschweig, Germany
| | - Rolf Hilgenfeld
- Institute of Biochemistry, Center for Structural and Cell Biology in Medicine, University of Lübeck, 23562 Lübeck, Germany.
- German Center for Infection Research (DZIF), Hamburg-Lübeck-Borstel-Riems Site, University of Lübeck, 23562 Lübeck, Germany
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10
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Bogutzki A, Naue N, Litz L, Pich A, Curth U. E. coli primase and DNA polymerase III holoenzyme are able to bind concurrently to a primed template during DNA replication. Sci Rep 2019; 9:14460. [PMID: 31595021 PMCID: PMC6783573 DOI: 10.1038/s41598-019-51031-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Accepted: 09/24/2019] [Indexed: 11/15/2022] Open
Abstract
During DNA replication in E. coli, a switch between DnaG primase and DNA polymerase III holoenzyme (pol III) activities has to occur every time when the synthesis of a new Okazaki fragment starts. As both primase and the χ subunit of pol III interact with the highly conserved C-terminus of single-stranded DNA-binding protein (SSB), it had been proposed that the binding of both proteins to SSB is mutually exclusive. Using a replication system containing the origin of replication of the single-stranded DNA phage G4 (G4ori) saturated with SSB, we tested whether DnaG and pol III can bind concurrently to the primed template. We found that the addition of pol III does not lead to a displacement of primase, but to the formation of higher complexes. Even pol III-mediated primer elongation by one or several DNA nucleotides does not result in the dissociation of DnaG. About 10 nucleotides have to be added in order to displace one of the two primase molecules bound to SSB-saturated G4ori. The concurrent binding of primase and pol III is highly plausible, since even the SSB tetramer situated directly next to the 3′-terminus of the primer provides four C-termini for protein-protein interactions.
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Affiliation(s)
- Andrea Bogutzki
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, 30625, Carl-Neuberg-Str. 1, Germany
| | - Natalie Naue
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, 30625, Carl-Neuberg-Str. 1, Germany.,Inamed GmbH, Gauting, 82131, Germany
| | - Lidia Litz
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, 30625, Carl-Neuberg-Str. 1, Germany
| | - Andreas Pich
- Institute for Toxicology, Hannover Medical School, Hannover, 30625, Carl-Neuberg-Str. 1, Germany
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, 30625, Carl-Neuberg-Str. 1, Germany.
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11
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Zumbrägel FK, Machtens DA, Curth U, Lüder CG, Reubold TF, Eschenburg S. Survivin does not influence the anti-apoptotic action of XIAP on caspase-9. Biochem Biophys Res Commun 2017; 482:530-535. [DOI: 10.1016/j.bbrc.2016.11.094] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Accepted: 11/15/2016] [Indexed: 10/20/2022]
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12
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Reubold TF, Faelber K, Plattner N, Posor Y, Ketel K, Curth U, Schlegel J, Anand R, Manstein DJ, Noé F, Haucke V, Daumke O, Eschenburg S. Crystal structure of the dynamin tetramer. Nature 2015; 525:404-8. [PMID: 26302298 DOI: 10.1038/nature14880] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 08/03/2015] [Indexed: 12/21/2022]
Abstract
The mechanochemical protein dynamin is the prototype of the dynamin superfamily of large GTPases, which shape and remodel membranes in diverse cellular processes. Dynamin forms predominantly tetramers in the cytosol, which oligomerize at the neck of clathrin-coated vesicles to mediate constriction and subsequent scission of the membrane. Previous studies have described the architecture of dynamin dimers, but the molecular determinants for dynamin assembly and its regulation have remained unclear. Here we present the crystal structure of the human dynamin tetramer in the nucleotide-free state. Combining structural data with mutational studies, oligomerization measurements and Markov state models of molecular dynamics simulations, we suggest a mechanism by which oligomerization of dynamin is linked to the release of intramolecular autoinhibitory interactions. We elucidate how mutations that interfere with tetramer formation and autoinhibition can lead to the congenital muscle disorders Charcot-Marie-Tooth neuropathy and centronuclear myopathy, respectively. Notably, the bent shape of the tetramer explains how dynamin assembles into a right-handed helical oligomer of defined diameter, which has direct implications for its function in membrane constriction.
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Affiliation(s)
- Thomas F Reubold
- Institut für Biophysikalische Chemie, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Katja Faelber
- Max-Delbrück-Centrum für Molekulare Medizin, Kristallographie, Robert-Rössle-Straße 10, 13125 Berlin, Germany
| | - Nuria Plattner
- Institut für Mathematik, Freie Universität Berlin, Arnimallee 6, 14195 Berlin, Germany
| | - York Posor
- Leibniz-Institut für Molekulare Pharmakologie, Robert-Rössle-Straße 10, 13125 Berlin, Germany
| | - Katharina Ketel
- Leibniz-Institut für Molekulare Pharmakologie, Robert-Rössle-Straße 10, 13125 Berlin, Germany
| | - Ute Curth
- Institut für Biophysikalische Chemie, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.,Forschungseinrichtung Strukturanalyse, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Jeanette Schlegel
- Max-Delbrück-Centrum für Molekulare Medizin, Kristallographie, Robert-Rössle-Straße 10, 13125 Berlin, Germany
| | - Roopsee Anand
- Institut für Biophysikalische Chemie, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Dietmar J Manstein
- Institut für Biophysikalische Chemie, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.,Forschungseinrichtung Strukturanalyse, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Frank Noé
- Institut für Mathematik, Freie Universität Berlin, Arnimallee 6, 14195 Berlin, Germany
| | - Volker Haucke
- Leibniz-Institut für Molekulare Pharmakologie, Robert-Rössle-Straße 10, 13125 Berlin, Germany.,Institut für Chemie und Biochemie, Freie Universität Berlin, Takustraße 6, 14195 Berlin, Germany
| | - Oliver Daumke
- Max-Delbrück-Centrum für Molekulare Medizin, Kristallographie, Robert-Rössle-Straße 10, 13125 Berlin, Germany.,Institut für Chemie und Biochemie, Freie Universität Berlin, Takustraße 6, 14195 Berlin, Germany
| | - Susanne Eschenburg
- Institut für Biophysikalische Chemie, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
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13
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Lee C, Wigren E, Trček J, Peters V, Kim J, Hasni MS, Nimtz M, Lindqvist Y, Park C, Curth U, Lünsdorf H, Römling U. A novel protein quality control mechanism contributes to heat shock resistance of worldwide-distributed Pseudomonas aeruginosa clone C strains. Environ Microbiol 2015; 17:4511-26. [PMID: 26014207 DOI: 10.1111/1462-2920.12915] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2015] [Accepted: 05/19/2015] [Indexed: 11/30/2022]
Abstract
Pseudomonas aeruginosa is a highly successful nosocomial pathogen capable of causing a wide variety of infections with clone C strains most prevalent worldwide. In this study, we initially characterize a molecular mechanism of survival unique to clone C strains. We identified a P. aeruginosa clone C-specific genomic island (PACGI-1) that contains the highly expressed small heat shock protein sHsp20c, the founding member of a novel subclass of class B bacterial small heat shock proteins. sHsp20c and adjacent gene products are involved in resistance against heat shock. Heat stable sHsp20c is unconventionally expressed in stationary phase in a wide temperature range from 20 to 42°C. Purified sHsp20c has characteristic features of small heat shock protein class B as it is monodisperse, forms sphere-like 24-meric oligomers and exhibits significant chaperone activity. As the P. aeruginosa clone C population is significantly more heat shock resistant than genetically unrelated P. aeruginosa strains without sHsp20c, the horizontally acquired shsp20c operon might contribute to the survival of worldwide-distributed clone C strains.
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Affiliation(s)
- Changhan Lee
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Edvard Wigren
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Janja Trček
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Verena Peters
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Jihong Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 305-701, Korea
| | - Muhammad Sharif Hasni
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Manfred Nimtz
- The Helmholtz Center for Infection Research, Braunschweig, 38124, Germany
| | - Ylva Lindqvist
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Chankyu Park
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, 305-701, Korea
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, 30625, Germany
| | - Heinrich Lünsdorf
- The Helmholtz Center for Infection Research, Braunschweig, 38124, Germany
| | - Ute Römling
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
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14
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Zhao H, Ghirlando R, Alfonso C, Arisaka F, Attali I, Bain DL, Bakhtina MM, Becker DF, Bedwell GJ, Bekdemir A, Besong TMD, Birck C, Brautigam CA, Brennerman W, Byron O, Bzowska A, Chaires JB, Chaton CT, Cölfen H, Connaghan KD, Crowley KA, Curth U, Daviter T, Dean WL, Díez AI, Ebel C, Eckert DM, Eisele LE, Eisenstein E, England P, Escalante C, Fagan JA, Fairman R, Finn RM, Fischle W, de la Torre JG, Gor J, Gustafsson H, Hall D, Harding SE, Cifre JGH, Herr AB, Howell EE, Isaac RS, Jao SC, Jose D, Kim SJ, Kokona B, Kornblatt JA, Kosek D, Krayukhina E, Krzizike D, Kusznir EA, Kwon H, Larson A, Laue TM, Le Roy A, Leech AP, Lilie H, Luger K, Luque-Ortega JR, Ma J, May CA, Maynard EL, Modrak-Wojcik A, Mok YF, Mücke N, Nagel-Steger L, Narlikar GJ, Noda M, Nourse A, Obsil T, Park CK, Park JK, Pawelek PD, Perdue EE, Perkins SJ, Perugini MA, Peterson CL, Peverelli MG, Piszczek G, Prag G, Prevelige PE, Raynal BDE, Rezabkova L, Richter K, Ringel AE, Rosenberg R, Rowe AJ, Rufer AC, Scott DJ, Seravalli JG, Solovyova AS, Song R, Staunton D, Stoddard C, Stott K, Strauss HM, Streicher WW, Sumida JP, Swygert SG, Szczepanowski RH, Tessmer I, Toth RT, Tripathy A, Uchiyama S, Uebel SFW, Unzai S, Gruber AV, von Hippel PH, Wandrey C, Wang SH, Weitzel SE, Wielgus-Kutrowska B, Wolberger C, Wolff M, Wright E, Wu YS, Wubben JM, Schuck P. A multilaboratory comparison of calibration accuracy and the performance of external references in analytical ultracentrifugation. PLoS One 2015; 10:e0126420. [PMID: 25997164 PMCID: PMC4440767 DOI: 10.1371/journal.pone.0126420] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2015] [Accepted: 04/02/2015] [Indexed: 12/21/2022] Open
Abstract
Analytical ultracentrifugation (AUC) is a first principles based method to determine absolute sedimentation coefficients and buoyant molar masses of macromolecules and their complexes, reporting on their size and shape in free solution. The purpose of this multi-laboratory study was to establish the precision and accuracy of basic data dimensions in AUC and validate previously proposed calibration techniques. Three kits of AUC cell assemblies containing radial and temperature calibration tools and a bovine serum albumin (BSA) reference sample were shared among 67 laboratories, generating 129 comprehensive data sets. These allowed for an assessment of many parameters of instrument performance, including accuracy of the reported scan time after the start of centrifugation, the accuracy of the temperature calibration, and the accuracy of the radial magnification. The range of sedimentation coefficients obtained for BSA monomer in different instruments and using different optical systems was from 3.655 S to 4.949 S, with a mean and standard deviation of (4.304 ± 0.188) S (4.4%). After the combined application of correction factors derived from the external calibration references for elapsed time, scan velocity, temperature, and radial magnification, the range of s-values was reduced 7-fold with a mean of 4.325 S and a 6-fold reduced standard deviation of ± 0.030 S (0.7%). In addition, the large data set provided an opportunity to determine the instrument-to-instrument variation of the absolute radial positions reported in the scan files, the precision of photometric or refractometric signal magnitudes, and the precision of the calculated apparent molar mass of BSA monomer and the fraction of BSA dimers. These results highlight the necessity and effectiveness of independent calibration of basic AUC data dimensions for reliable quantitative studies.
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Affiliation(s)
- Huaying Zhao
- Dynamics of Macromolecular Assembly Section, Laboratory of Cellular Imaging and Macromolecular Biophysics, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland, 20892, United States of America
| | - Rodolfo Ghirlando
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, 20892, United States of America
| | - Carlos Alfonso
- Analytical Ultracentrifugacion and Light Scattering Facility, Centro de Investigaciones Biológicas, CSIC, Madrid, 28040, Spain
| | - Fumio Arisaka
- Life Science Research Center, Nihon University, College of Bioresource Science, Fujisawa, 252–0880, Japan
| | - Ilan Attali
- Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv, 69978, Israel
| | - David L. Bain
- Department of Pharmaceutical Sciences, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado, 80045, United States of America
| | - Marina M. Bakhtina
- Department of Chemistry and Biochemistry, Center for Retrovirus Research, and Center for RNA Biology, The Ohio State University, Columbus, Ohio, 43210, United States of America
| | - Donald F. Becker
- Redox Biology Center, University of Nebraska-Lincoln, Lincoln, Nebraska, 68588, United States of America
| | - Gregory J. Bedwell
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, 35294, United States of America
| | - Ahmet Bekdemir
- Supramolecular Nanomaterials and Interfaces Laboratory, Institute of Materials, École Polytechnique Fédérale de Lausanne, Lausanne, CH-1015, Switzerland
| | - Tabot M. D. Besong
- National Centre for Macromolecular Hydrodynamics, University of Nottingham, School of Biosciences, Sutton Bonington, LE12 5RD, United Kingdom
| | | | - Chad A. Brautigam
- Department of Biophysics, The University of Texas Southwestern Medical Center, Dallas, Texas, 75390, United States of America
| | - William Brennerman
- Beckman Coulter, Inc., Life Science Division, Indianapolis, Indiana, 46268, United States of America
| | - Olwyn Byron
- School of Life Sciences, University of Glasgow, Glasgow, G37TT, United Kingdom
| | - Agnieszka Bzowska
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Warsaw, 02–089, Poland
| | - Jonathan B. Chaires
- JG Brown Cancer Center, University of Louisville, Louisville, Kentucky, 40202, United States of America
| | - Catherine T. Chaton
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, Cincinnati, Ohio, 45267, United States of America
| | - Helmut Cölfen
- Physical Chemistry, University of Konstanz, 78457, Konstanz, Germany
| | - Keith D. Connaghan
- Department of Pharmaceutical Sciences, University of Colorado Denver Anschutz Medical Campus, Aurora, Colorado, 80045, United States of America
| | - Kimberly A. Crowley
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, 01605, United States of America
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, 30625, Hannover, Germany
| | - Tina Daviter
- Institute of Structural and Molecular Biology Biophysics Centre, Birkbeck, University of London and University College London, London, WC1E 7HX, United Kingdom
| | - William L. Dean
- JG Brown Cancer Center, University of Louisville, Louisville, Kentucky, 40202, United States of America
| | - Ana I. Díez
- Department of Physical Chemistry, University of Murcia, Murcia, 30071, Spain
| | - Christine Ebel
- Univ. Grenoble Alpes, IBS, F-38044, Grenoble, France
- CNRS, IBS, F-38044, Grenoble, France
- CEA, IBS, F-38044, Grenoble, France
| | - Debra M. Eckert
- Protein Interactions Core, Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, 84112, United States of America
| | - Leslie E. Eisele
- Wadsworth Center, New York State Department of Health, Albany, New York, 12208, United States of America
| | - Edward Eisenstein
- Institute for Bioscience and Biotechnology Research, Fischell Department of Bioengineering, University of Maryland, Rockville, Maryland, 20850, United States of America
| | - Patrick England
- Institut Pasteur, Centre of Biophysics of Macromolecules and Their Interactions, Paris, 75724, France
| | - Carlos Escalante
- Department of Physiology and Biophysics, School of Medicine, Virginia Commonwealth University, Richmond, Virginia, 23220, United States of America
| | - Jeffrey A. Fagan
- Materials Science and Engineering Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland, 20899, United States of America
| | - Robert Fairman
- Department of Biology, Haverford College, Haverford, Pennsylvania, 19041, United States of America
| | - Ron M. Finn
- Laboratory of Chromatin Biochemistry, Max Planck Institute for Biophysical Chemistry, 37077, Göttingen, Germany
| | - Wolfgang Fischle
- Laboratory of Chromatin Biochemistry, Max Planck Institute for Biophysical Chemistry, 37077, Göttingen, Germany
| | | | - Jayesh Gor
- Department of Structural and Molecular Biology, Darwin Building, University College London, London, WC1E 6BT, United Kingdom
| | | | - Damien Hall
- Research School of Chemistry, Section on Biological Chemistry, The Australian National University, Acton, ACT 0200, Australia
| | - Stephen E. Harding
- National Centre for Macromolecular Hydrodynamics, University of Nottingham, School of Biosciences, Sutton Bonington, LE12 5RD, United Kingdom
| | | | - Andrew B. Herr
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, Cincinnati, Ohio, 45267, United States of America
| | - Elizabeth E. Howell
- Biochemistry, Cell and Molecular Biology Department, University of Tennessee, Knoxville, Tennessee, 37996–0840, United States of America
| | - Richard S. Isaac
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, 94158, United States of America
- Tetrad Graduate Program, University of California San Francisco, San Francisco, California, 94158, United States of America
| | - Shu-Chuan Jao
- Institute of Biological Chemistry, Academia Sinica, Taipei, 115, Taiwan
- Biophysics Core Facility, Scientific Instrument Center, Academia Sinica, Taipei, 115, Taiwan
| | - Davis Jose
- Institute of Molecular Biology and Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon, 97403, United States of America
| | - Soon-Jong Kim
- Department of Chemistry, Mokpo National University, Muan, 534–729, Korea
| | - Bashkim Kokona
- Department of Biology, Haverford College, Haverford, Pennsylvania, 19041, United States of America
| | - Jack A. Kornblatt
- Enzyme Research Group, Concordia University, Montreal, Quebec, H4B 1R6, Canada
| | - Dalibor Kosek
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, Prague, 12843, Czech Republic
| | - Elena Krayukhina
- Department of Biotechnology, Graduate School of Engineering, Osaka University, Suita, Osaka, 565–0871, Japan
| | - Daniel Krzizike
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado, 80523, United States of America
| | - Eric A. Kusznir
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-LaRoche Ltd., Basel, 4070, Switzerland
| | - Hyewon Kwon
- Analytical Biopharmacy Core, University of Washington, Seattle, Washington, 98195, United States of America
| | - Adam Larson
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, 94158, United States of America
- Tetrad Graduate Program, University of California San Francisco, San Francisco, California, 94158, United States of America
| | - Thomas M. Laue
- Department of Biochemistry, University of New Hampshire, Durham, New Hampshire, 03824, United States of America
| | - Aline Le Roy
- Univ. Grenoble Alpes, IBS, F-38044, Grenoble, France
- CNRS, IBS, F-38044, Grenoble, France
- CEA, IBS, F-38044, Grenoble, France
| | - Andrew P. Leech
- Technology Facility, Department of Biology, University of York, York, YO10 5DD, United Kingdom
| | - Hauke Lilie
- Institute of Biochemistry and Biotechnology, Martin-Luther University Halle-Wittenberg, 06120, Halle, Germany
| | - Karolin Luger
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado, 80523, United States of America
| | - Juan R. Luque-Ortega
- Analytical Ultracentrifugacion and Light Scattering Facility, Centro de Investigaciones Biológicas, CSIC, Madrid, 28040, Spain
| | - Jia Ma
- Dynamics of Macromolecular Assembly Section, Laboratory of Cellular Imaging and Macromolecular Biophysics, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland, 20892, United States of America
| | - Carrie A. May
- Department of Biochemistry, University of New Hampshire, Durham, New Hampshire, 03824, United States of America
| | - Ernest L. Maynard
- Department of Biochemistry, Uniformed Services University of the Health Sciences, Bethesda, Maryland, 20814, United States of America
| | - Anna Modrak-Wojcik
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Warsaw, 02–089, Poland
| | - Yee-Foong Mok
- Department of Biochemistry and Molecular Biology, Bio21 Instute of Molecular Science and Biotechnology, University of Melbourne, Parkville, 3010, Victoria, Australia
| | - Norbert Mücke
- Biophysics of Macromolecules, German Cancer Research Center, Heidelberg, 69120, Germany
| | | | - Geeta J. Narlikar
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, 94158, United States of America
| | - Masanori Noda
- Department of Biotechnology, Graduate School of Engineering, Osaka University, Suita, Osaka, 565–0871, Japan
| | - Amanda Nourse
- Molecular Interaction Analysis Shared Resource, St. Jude Children’s Research Hospital, Memphis, Tennessee, 38105, United States of America
| | - Tomas Obsil
- Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague, Prague, 12843, Czech Republic
| | - Chad K. Park
- Analytical Biophysics & Materials Characterization, Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona, 85721, United States of America
| | - Jin-Ku Park
- Central Instrument Center, Mokpo National University, Muan, 534–729, Korea
| | - Peter D. Pawelek
- Department of Chemistry and Biochemistry, Concordia University, Montreal, Quebec, H4B 1R6, Canada
| | - Erby E. Perdue
- Beckman Coulter, Inc., Life Science Division, Indianapolis, Indiana, 46268, United States of America
| | - Stephen J. Perkins
- Department of Structural and Molecular Biology, Darwin Building, University College London, London, WC1E 6BT, United Kingdom
| | - Matthew A. Perugini
- Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, 3086, Australia
| | - Craig L. Peterson
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, 01605, United States of America
| | - Martin G. Peverelli
- Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, 3086, Australia
| | - Grzegorz Piszczek
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, 20892, United States of America
| | - Gali Prag
- Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Peter E. Prevelige
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, 35294, United States of America
| | - Bertrand D. E. Raynal
- Institut Pasteur, Centre of Biophysics of Macromolecules and Their Interactions, Paris, 75724, France
| | - Lenka Rezabkova
- Laboratory of Biomolecular Research, Department of Biology and Chemistry, Paul Scherrer Institute, 5232, Villigen PSI, Switzerland
| | - Klaus Richter
- Department of Chemistry and Center for Integrated Protein Science, Technische Universität München, 85748, Garching, Germany
| | - Alison E. Ringel
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, 21205, United States of America
| | - Rose Rosenberg
- Physical Chemistry, University of Konstanz, 78457, Konstanz, Germany
| | - Arthur J. Rowe
- National Centre for Macromolecular Hydrodynamics, University of Nottingham, School of Biosciences, Sutton Bonington, LE12 5RD, United Kingdom
| | - Arne C. Rufer
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-LaRoche Ltd., Basel, 4070, Switzerland
| | - David J. Scott
- Research Complex at Harwell, Rutherford Appleton Laboratory, Oxfordshire, OX11 0FA, United Kingdom
| | - Javier G. Seravalli
- Redox Biology Center, University of Nebraska-Lincoln, Lincoln, Nebraska, 68588, United States of America
| | - Alexandra S. Solovyova
- Proteome and Protein Analysis, University of Newcastle, Newcastle upon Tyne, NE1 7RU, United Kingdom
| | - Renjie Song
- Wadsworth Center, New York State Department of Health, Albany, New York, 12208, United States of America
| | - David Staunton
- Molecular Biophysics Suite, Department of Biochemistry, Oxford, Oxon, OX1 3QU, United Kingdom
| | - Caitlin Stoddard
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, 94158, United States of America
- Tetrad Graduate Program, University of California San Francisco, San Francisco, California, 94158, United States of America
| | - Katherine Stott
- Biochemistry Department, University of Cambridge, Cambridge, CB2 1GA, United Kingdom
| | | | - Werner W. Streicher
- Protein Function and Interactions, Novo Nordisk Foundation Center for Protein Research, Copenhagen, 2200, Denmark
| | - John P. Sumida
- Analytical Biopharmacy Core, University of Washington, Seattle, Washington, 98195, United States of America
| | - Sarah G. Swygert
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, 01605, United States of America
| | - Roman H. Szczepanowski
- Core Facility, International Institute of Molecular and Cell Biology, Warsaw, 02–109, Poland
| | - Ingrid Tessmer
- Rudolf Virchow Center for Experimental Biomedicine, University of Würzburg, 97080, Würzburg, Germany
| | - Ronald T. Toth
- Macromolecule and Vaccine Stabilization Center, University of Kansas, Lawrence, Kansas, 66047, United States of America
| | - Ashutosh Tripathy
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States of America
| | - Susumu Uchiyama
- Department of Biotechnology, Graduate School of Engineering, Osaka University, Suita, Osaka, 565–0871, Japan
| | - Stephan F. W. Uebel
- Biochemistry Core Facility, Max Planck Institute of Biochemistry, 82152, Martinsried, Germany
| | - Satoru Unzai
- Drug Design Laboratory, Graduate School of Medical Life Science, Yokohama City University, Yokohama, 230–0045, Japan
| | - Anna Vitlin Gruber
- Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Peter H. von Hippel
- Institute of Molecular Biology and Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon, 97403, United States of America
| | - Christine Wandrey
- Laboratoire de Médecine Régénérative et de Pharmacobiologie, Ecole Polytechnique Fédérale de Lausanne, Lausanne, CH-1015, Switzerland
| | - Szu-Huan Wang
- Biophysics Core Facility, Scientific Instrument Center, Academia Sinica, Taipei, 115, Taiwan
| | - Steven E. Weitzel
- Institute of Molecular Biology and Department of Chemistry and Biochemistry, University of Oregon, Eugene, Oregon, 97403, United States of America
| | - Beata Wielgus-Kutrowska
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Warsaw, 02–089, Poland
| | - Cynthia Wolberger
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, 21205, United States of America
| | - Martin Wolff
- ICS-6, Structural Biochemistry, Research Center Juelich, 52428, Juelich, Germany
| | - Edward Wright
- Biochemistry, Cell and Molecular Biology Department, University of Tennessee, Knoxville, Tennessee, 37996–0840, United States of America
| | - Yu-Sung Wu
- Department of Chemical & Biomolecular Engineering, University of Delaware, Newark, Delaware, 19716, United States of America
| | - Jacinta M. Wubben
- Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria, 3086, Australia
| | - Peter Schuck
- Dynamics of Macromolecular Assembly Section, Laboratory of Cellular Imaging and Macromolecular Biophysics, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, Maryland, 20892, United States of America
- * E-mail:
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Kuhle K, Krausze J, Curth U, Rössle M, Heuner K, Lang C, Flieger A. Oligomerization inhibits Legionella pneumophila PlaB phospholipase A activity. J Biol Chem 2014; 289:18657-66. [PMID: 24811180 DOI: 10.1074/jbc.m114.573196] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The intracellularly replicating lung pathogen Legionella pneumophila consists of an extraordinary variety of phospholipases, including at least 15 different phospholipases A (PLA). Among them, PlaB, the first characterized member of a novel lipase family, is a hemolytic virulence factor that exhibits the most prominent PLA activity in L. pneumophila. We analyzed here protein oligomerization, the importance of oligomerization for activity, addressed further essential regions for activity within the PlaB C terminus, and the significance of PlaB-derived lipolytic activity for L. pneumophila intracellular replication. We determined by means of analytical ultracentrifugation and small angle x-ray scattering analysis that PlaB forms homodimers and homotetramers. The C-terminal 5, 10, or 15 amino acids, although the individual regions contributed to PLA activity, were not essential for protein tetramerization. Infection of mouse macrophages with L. pneumophila wild type, plaB knock-out mutant, and plaB complementing or various mutated plaB-harboring strains showed that catalytic activity of PlaB promotes intracellular replication. We observed that PlaB was most active in the lower nanomolar concentration range but not at or only at a low level at concentration above 0.1 μm where it exists in a dimer/tetramer equilibrium. We therefore conclude that PlaB is a virulence factor that, on the one hand, assembles in inactive tetramers at micromolar concentrations. On the other hand, oligomer dissociation at nanomolar concentrations activates PLA activity. Our data highlight the first example of concentration-dependent phospholipase inactivation by tetramerization, which may protect the bacterium from internal PLA activity, but enzyme dissociation may allow its activation after export.
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Affiliation(s)
- Katja Kuhle
- From the Robert Koch-Institut, 38855 Wernigerode
| | - Joern Krausze
- the Helmholtz Center for Infection Research, 38124 Braunschweig
| | - Ute Curth
- the Institute for Biophysical Chemistry, Hannover Medical School, 30625 Hannover
| | - Manfred Rössle
- the European Molecular Biology Laboratory, 22603 Hamburg Branch, c/o DESY, Hamburg, and the Lübeck University of Applied Sciences, 23562 Lübeck, Germany
| | - Klaus Heuner
- From the Robert Koch-Institut, 38855 Wernigerode
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16
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Ghirlando R, Zhao H, Balbo A, Piszczek G, Curth U, Brautigam CA, Schuck P. Measurement of the temperature of the resting rotor in analytical ultracentrifugation. Anal Biochem 2014; 458:37-9. [PMID: 24799348 DOI: 10.1016/j.ab.2014.04.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 04/21/2014] [Accepted: 04/22/2014] [Indexed: 11/27/2022]
Abstract
Accurate measurements of rotor temperature are critical for the interpretation of hydrodynamic parameters in analytical ultracentrifugation. We have recently developed methods for a more accurate determination of the temperature of a spinning rotor using iButton temperature loggers. Here we report that the temperature measured with the iButton on the counterbalance of a resting rotor, following thermal equilibration under high vacuum, closely corresponded to the temperature of the spinning rotor with a precision better than 0.2°C. This strategy offers an inexpensive and straightforward approach to monitor the accuracy of the temperature calibration and determine corrective temperature offsets.
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Affiliation(s)
- Rodolfo Ghirlando
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Huaying Zhao
- Dynamics of Macromolecular Assembly Section, Laboratory of Cellular Imaging and Macromolecular Biophysics, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA
| | - Andrea Balbo
- Bioengineering and Physical Science Shared Resource, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA
| | - Grzegorz Piszczek
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Chad A Brautigam
- Department of Biophysics, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Peter Schuck
- Dynamics of Macromolecular Assembly Section, Laboratory of Cellular Imaging and Macromolecular Biophysics, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA.
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17
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Zhao H, Ghirlando R, Piszczek G, Curth U, Brautigam CA, Schuck P. Recorded scan times can limit the accuracy of sedimentation coefficients in analytical ultracentrifugation. Anal Biochem 2013; 437:104-8. [PMID: 23458356 PMCID: PMC3676908 DOI: 10.1016/j.ab.2013.02.011] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 02/13/2013] [Accepted: 02/14/2013] [Indexed: 10/27/2022]
Abstract
We report systematic and large inaccuracies in the recorded elapsed time in data files from the analytical ultracentrifuge, leading to overestimates of the sedimentation coefficients of up to 10%. This far exceeds previously considered factors contributing to the uncertainty in this parameter and has significant ramifications for derived parameters such as hydrodynamic shape and molar mass estimates. The source of this error is currently unknown, but we found it to be quantitatively consistent across different instruments, increasing with rotor speed. Furthermore, its occurrence appears to correlate with the use of the latest data acquisition software from the manufacturer, in use in some of our laboratories for nearly 2 years. Many of the recently published sedimentation coefficients may need to be reexamined. The problem can be easily recognized by comparing the file timestamps provided by the operating system with the elapsed scan times recorded within the data files. Therefore, we implemented a routine in SEDFIT that can automatically examine the data files, alert the user to significant discrepancies, and correct the scan times accordingly. This eliminates errors in the recorded scan times.
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Affiliation(s)
- Huaying Zhao
- Dynamics of Macromolecular Assembly Section, Laboratory of Cellular Imaging and Macromolecular Biophysics, National Institute of Biomedical Imaging and Bioengineering, NIH, Bethesda, MD
| | - Rodolfo Ghirlando
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD
| | - Grzegorz Piszczek
- Biochemistry and Biophysics Center, National Heart, Lung and Blood Institute, NIH, Bethesda, MD
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Chad A. Brautigam
- Department of Biophysics, The University of Texas Southwestern Medical Center, Dallas, TX
| | - Peter Schuck
- Dynamics of Macromolecular Assembly Section, Laboratory of Cellular Imaging and Macromolecular Biophysics, National Institute of Biomedical Imaging and Bioengineering, NIH, Bethesda, MD
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18
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Ringel P, Krausze J, van den Heuvel J, Curth U, Pierik AJ, Herzog S, Mendel RR, Kruse T. Biochemical characterization of molybdenum cofactor-free nitrate reductase from Neurospora crassa. J Biol Chem 2013; 288:14657-14671. [PMID: 23539622 DOI: 10.1074/jbc.m113.457960] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Nitrate reductase (NR) is a complex molybdenum cofactor (Moco)-dependent homodimeric metalloenzyme that is vitally important for autotrophic organism as it catalyzes the first and rate-limiting step of nitrate assimilation. Beside Moco, eukaryotic NR also binds FAD and heme as additional redox active cofactors, and these are involved in electron transfer from NAD(P)H to the enzyme molybdenum center where reduction of nitrate to nitrite takes place. We report the first biochemical characterization of a Moco-free eukaryotic NR from the fungus Neurospora crassa, documenting that Moco is necessary and sufficient to induce dimer formation. The molybdenum center of NR reconstituted in vitro from apo-NR and Moco showed an EPR spectrum identical to holo-NR. Analysis of mutants unable to bind heme or FAD revealed that insertion of Moco into NR occurs independent from the insertion of any other NR redox cofactor. Furthermore, we showed that at least in vitro the active site formation of NR is an autonomous process.
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Affiliation(s)
- Phillip Ringel
- Department of Plant Biology, Braunschweig University of Technology, 38106 Braunschweig, Germany
| | - Joern Krausze
- Department of Molecular Structural Biology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany
| | - Joop van den Heuvel
- Department of Molecular Structural Biology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Antonio J Pierik
- Core Facility for Protein Spectroscopy, Institute of Cytobiology and Cytopathology, Phillips University, 35032 Marburg, Germany
| | - Stephanie Herzog
- Department of Plant Biology, Braunschweig University of Technology, 38106 Braunschweig, Germany
| | - Ralf R Mendel
- Department of Plant Biology, Braunschweig University of Technology, 38106 Braunschweig, Germany.
| | - Tobias Kruse
- Department of Plant Biology, Braunschweig University of Technology, 38106 Braunschweig, Germany
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Naue N, Beerbaum M, Bogutzki A, Schmieder P, Curth U. The helicase-binding domain of Escherichia coli DnaG primase interacts with the highly conserved C-terminal region of single-stranded DNA-binding protein. Nucleic Acids Res 2013; 41:4507-17. [PMID: 23430154 PMCID: PMC3632105 DOI: 10.1093/nar/gkt107] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
During bacterial DNA replication, DnaG primase and the χ subunit of DNA polymerase III compete for binding to single-stranded DNA-binding protein (SSB), thus facilitating the switch between priming and elongation. SSB proteins play an essential role in DNA metabolism by protecting single-stranded DNA and by mediating several important protein-protein interactions. Although an interaction of SSB with primase has been previously reported, it was unclear which domains of the two proteins are involved. This study identifies the C-terminal helicase-binding domain of DnaG primase (DnaG-C) and the highly conserved C-terminal region of SSB as interaction sites. By ConSurf analysis, it can be shown that an array of conserved amino acids on DnaG-C forms a hydrophobic pocket surrounded by basic residues, reminiscent of known SSB-binding sites on other proteins. Using protein-protein cross-linking, site-directed mutagenesis, analytical ultracentrifugation and nuclear magnetic resonance spectroscopy, we demonstrate that these conserved amino acid residues are involved in the interaction with SSB. Even though the C-terminal domain of DnaG primase also participates in the interaction with DnaB helicase, the respective binding sites on the surface of DnaG-C do not overlap, as SSB binds to the N-terminal subdomain, whereas DnaB interacts with the ultimate C-terminus.
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Affiliation(s)
- Natalie Naue
- Institute for Biophysical Chemistry, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover, Germany
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Abstract
Bacterial single-stranded DNA-binding (SSB) proteins are essential for DNA metabolism, since they protect stretches of single-stranded DNA and are required for numerous crucial protein-protein interactions in DNA replication, recombination, and repair. At the lagging strand of the DNA replication fork of Escherichia coli, for example, SSB contacts not only DnaG primase but also the χ subunit of DNA polymerase III, thereby facilitating the switch between primase and polymerase activity. Here, we describe a powerful method that allows the study of interactions between SSB and its binding partners by sedimentation velocity experiments in an analytical ultracentrifuge. Whenever two molecules interact, a complex of a higher mass forms that can usually be distinguished from free binding partners by its different sedimentation behavior. As an example, we show how sedimentation velocity experiments of purified proteins can be employed to determine the binding parameters of the interaction of SSB and the χ subunit of DNA polymerase III from E. coli.
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Affiliation(s)
- Natalie Naue
- Hannover Medical School, Institute for Biophysical Chemistry, Hannover, Germany
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21
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Wyszomirski KH, Curth U, Alves J, Mackeldanz P, Möncke-Buchner E, Schutkowski M, Krüger DH, Reuter M. Type III restriction endonuclease EcoP15I is a heterotrimeric complex containing one Res subunit with several DNA-binding regions and ATPase activity. Nucleic Acids Res 2011; 40:3610-22. [PMID: 22199260 PMCID: PMC3333885 DOI: 10.1093/nar/gkr1239] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
For efficient DNA cleavage, the Type III restriction endonuclease EcoP15I communicates with two inversely oriented recognition sites in an ATP-dependent process. EcoP15I consists of methylation (Mod) and restriction (Res) subunits forming a multifunctional enzyme complex able to methylate or to cleave DNA. In this study, we determined by different analytical methods that EcoP15I contains a single Res subunit in a Mod(2)Res stoichiometry. The Res subunit comprises a translocase (Tr) domain carrying functional motifs of superfamily 2 helicases and an endonuclease domain with a PD..D/EXK motif. We show that the isolated Tr domain retains ATP-hydrolyzing activity and binds single- and double-stranded DNA in a sequence-independent manner. To localize the regions of DNA binding, we screened peptide arrays representing the entire Res sequence for their ability to interact with DNA. We discovered four DNA-binding regions in the Tr domain and two DNA-binding regions in the endonuclease domain. Modelling of the Tr domain shows that these multiple DNA-binding regions are located on the surface, free to interact with DNA. Interestingly, the positions of the DNA-binding regions are conserved among other Type III restriction endonucleases.
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Affiliation(s)
- Karol H Wyszomirski
- Institute of Medical Virology, Helmut-Ruska-Haus, Charité-Universitätsmedizin Berlin, Charitéplatz 1, D-10117 Berlin,Germany
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Fonfara I, Curth U, Pingoud A, Wende W. Creating highly specific nucleases by fusion of active restriction endonucleases and catalytically inactive homing endonucleases. Nucleic Acids Res 2011; 40:847-60. [PMID: 21965534 PMCID: PMC3258161 DOI: 10.1093/nar/gkr788] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Zinc-finger nucleases and TALE nucleases are produced by combining a specific DNA-binding module and a non-specific DNA-cleavage module, resulting in nucleases able to cleave DNA at a unique sequence. Here a new approach for creating highly specific nucleases was pursued by fusing a catalytically inactive variant of the homing endonuclease I-SceI, as DNA binding-module, to the type IIP restriction enzyme PvuII, as cleavage module. The fusion enzymes were designed to recognize a composite site comprising the recognition site of PvuII flanked by the recognition site of I-SceI. In order to reduce activity on PvuII sites lacking the flanking I-SceI sites, the enzymes were optimized so that the binding of I-SceI to its sites positions PvuII for cleavage of the composite site. This was achieved by optimization of the linker and by introducing amino acid substitutions in PvuII which decrease its activity or disturb its dimer interface. The most specific variant showed a more than 1000-fold preference for the addressed composite site over an unaddressed PvuII site. These results indicate that using a specific restriction enzyme, such as PvuII, as cleavage module, offers an alternative to the otherwise often used catalytic domain of FokI, which by itself does not contribute to the specificity of the engineered nuclease.
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Affiliation(s)
- Ines Fonfara
- Institut für Biochemie, Justus-Liebig-Universität Giessen, Heinrich-Buff-Ring 58, D-35392, Giessen, Germany
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23
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El Houry Mignan S, Witte G, Naue N, Curth U. Characterization of the χψ subcomplex of Pseudomonas aeruginosa DNA polymerase III. BMC Mol Biol 2011; 12:43. [PMID: 21955458 PMCID: PMC3197488 DOI: 10.1186/1471-2199-12-43] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Accepted: 09/28/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND DNA polymerase III, the main enzyme responsible for bacterial DNA replication, is composed of three sub-assemblies: the polymerase core, the β-sliding clamp, and the clamp loader. During replication, single-stranded DNA-binding protein (SSB) coats and protects single-stranded DNA (ssDNA) and also interacts with the χψ heterodimer, a sub-complex of the clamp loader. Whereas the χ subunits of Escherichia coli and Pseudomonas aeruginosa are about 40% homologous, P. aeruginosa ψ is twice as large as its E. coli counterpart, and contains additional sequences. It was shown that P. aeruginosa χψ together with SSB increases the activity of its cognate clamp loader 25-fold at low salt. The E. coli clamp loader, however, is insensitive to the addition of its cognate χψ under similar conditions. In order to find out distinguishing properties within P. aeruginosa χψ which account for this higher stimulatory effect, we characterized P. aeruginosa χψ by a detailed structural and functional comparison with its E. coli counterpart. RESULTS Using small-angle X-ray scattering, analytical ultracentrifugation, and homology-based modeling, we found the N-terminus of P. aeruginosa ψ to be unstructured. Under high salt conditions, the affinity of the χψ complexes from both organisms to their cognate SSB was similar. Under low salt conditions, P. aeruginosa χψ, contrary to E. coli χψ, binds to ssDNA via the N-terminus of ψ. Whereas it is also able to bind to double-stranded DNA, the affinity is somewhat reduced. CONCLUSIONS The binding to DNA, otherwise never reported for any other ψ protein, enhances the affinity of P. aeruginosa χψ towards the SSB/ssDNA complex and very likely contributes to the higher stimulatory effect of P. aeruginosa χψ on the clamp loader. We also observed DNA-binding activity for P. putida χψ, making this activity most probably a characteristic of the ψ proteins from the Pseudomonadaceae.
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Affiliation(s)
- Sirine El Houry Mignan
- Institute for Biophysical Chemistry, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Gregor Witte
- Department of Biochemistry, Gene Center of the Ludwig-Maximilians-University Munich, Feodor-Lynen-Str. 25, D-81377 Munich, Germany
- Center for Integrated Protein Sciences (CIPSM), Gene Center of the Ludwig-Maximilians-University Munich, Feodor-Lynen-Str. 25, D-81377 Munich, Germany
- Munich Center for Advanced Photonics (MAP), Gene Center of the Ludwig-Maximilians-University Munich, Feodor-Lynen-Str. 25, D-81377 Munich, Germany
| | - Natalie Naue
- Institute for Biophysical Chemistry, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Ute Curth
- Institute for Biophysical Chemistry, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
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Winkler I, Marx AD, Lariviere D, Manelyte L, Giron-Monzon L, Heinze RJ, Cristovao M, Reumer A, Curth U, Sixma TK, Friedhoff P. Chemical trapping of the dynamic MutS-MutL complex formed in DNA mismatch repair in Escherichia coli. J Biol Chem 2011. [DOI: 10.1074/jbc.a110.187641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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25
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Winkler I, Marx AD, Lariviere D, Heinze RJ, Cristovao M, Reumer A, Curth U, Sixma TK, Friedhoff P. Chemical trapping of the dynamic MutS-MutL complex formed in DNA mismatch repair in Escherichia coli. J Biol Chem 2011; 286:17326-37. [PMID: 21454657 DOI: 10.1074/jbc.m110.187641] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The ternary complex comprising MutS, MutL, and DNA is a key intermediate in DNA mismatch repair. We used chemical cross-linking and fluorescence resonance energy transfer (FRET) to study the interaction between MutS and MutL and to shed light onto the structure of this complex. Via chemical cross-linking, we could stabilize this dynamic complex and identify the structural features of key events in DNA mismatch repair. We could show that in the complex between MutS and MutL the mismatch-binding and connector domains of MutS are in proximity to the N-terminal ATPase domain of MutL. The DNA- and nucleotide-dependent complex formation could be monitored by FRET using single cysteine variants labeled in the connector domain of MutS and the transducer domain of MutL, respectively. In addition, we could trap MutS after an ATP-induced conformational change by an intramolecular cross-link between Cys-93 of the mismatch-binding domain and Cys-239 of the connector domain.
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Affiliation(s)
- Ines Winkler
- Institute for Biochemistry, FB 08, Justus Liebig University, D-35392 Giessen, Germany
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26
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Naue N, Fedorov R, Pich A, Manstein DJ, Curth U. Site-directed mutagenesis of the χ subunit of DNA polymerase III and single-stranded DNA-binding protein of E. coli reveals key residues for their interaction. Nucleic Acids Res 2010; 39:1398-407. [PMID: 20972214 PMCID: PMC3045619 DOI: 10.1093/nar/gkq988] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
During DNA replication in Escherichia coli, single-stranded DNA-binding protein (SSB) protects single-stranded DNA from nuclease action and hairpin formation. It is known that the highly conserved C-terminus of SSB contacts the χ subunit of DNA polymerase III. However, there only exists a theoretical model in which the 11 C-terminal amino acids of SSB have been docked onto the surface of χ. In order to refine this model of SSB/χ interaction, we exchanged amino acids in χ and SSB by site-directed mutagenesis that are predicted to be of key importance. Detailed characterization of the interaction of these mutants by analytical ultracentrifugation shows that the interaction area is correctly predicted by the model; however, the SSB C-terminus binds in a different orientation to the χ surface. We show that evolutionary conserved residues of χ form a hydrophobic pocket to accommodate the ultimate two amino acids of SSB, P176 and F177. This pocket is surrounded by conserved basic residues, important for the SSB/χ interaction. Mass spectrometric analysis of χ protein cross-linked to a C-terminal peptide of SSB reveals that K132 of χ and D172 of SSB are in close contact. The proposed SSB-binding site resembles those described for RecQ and exonuclease I.
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Affiliation(s)
- Natalie Naue
- Hannover Medical School, Institute for Biophysical Chemistry, Carl-Neuberg-Strasse 1, 30625 Hannover, Germany
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27
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Hoffmann A, Dannhauser PN, Groos S, Hinrichsen L, Curth U, Ungewickell EJ. A Comparison of GFP-Tagged Clathrin Light Chains with Fluorochromated Light Chains In Vivo and In Vitro. Traffic 2010; 11:1129-40. [DOI: 10.1111/j.1600-0854.2010.01084.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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28
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Arad G, Hendel A, Urbanke C, Curth U, Livneh Z. Single-stranded DNA-binding protein recruits DNA polymerase V to primer termini on RecA-coated DNA. J Biol Chem 2008; 283:8274-82. [PMID: 18223256 DOI: 10.1074/jbc.m710290200] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Translesion DNA synthesis (TLS) by DNA polymerase V (polV) in Escherichia coli involves accessory proteins, including RecA and single-stranded DNA-binding protein (SSB). To elucidate the role of SSB in TLS we used an in vitro exonuclease protection assay and found that SSB increases the accessibility of 3' primer termini located at abasic sites in RecA-coated gapped DNA. The mutant SSB-113 protein, which is defective in protein-protein interactions, but not in DNA binding, was as effective as wild-type SSB in increasing primer termini accessibility, but deficient in supporting polV-catalyzed TLS. Consistently, the heterologous SSB proteins gp32, encoded by phage T4, and ICP8, encoded by herpes simplex virus 1, could replace E. coli SSB in the TLS reaction, albeit with lower efficiency. Immunoprecipitation experiments indicated that polV directly interacts with SSB and that this interaction is disrupted by the SSB-113 mutation. Taken together our results suggest that SSB functions to recruit polV to primer termini on RecA-coated DNA, operating by two mechanisms: 1) increasing the accessibility of 3' primer termini caused by binding of SSB to DNA and 2) a direct SSB-polV interaction mediated by the C terminus of SSB.
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Affiliation(s)
- Gali Arad
- Department of Biological Chemistry, Weizmann Institute of Science, Hertzl St, Rehovot, Israel
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29
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Fedorov R, Witte G, Urbanke C, Manstein DJ, Curth U. 3D structure of Thermus aquaticus single-stranded DNA-binding protein gives insight into the functioning of SSB proteins. Nucleic Acids Res 2006; 34:6708-17. [PMID: 17148487 PMCID: PMC1761420 DOI: 10.1093/nar/gkl1002] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In contrast to the majority of tetrameric SSB proteins, the recently discovered SSB proteins from the Thermus/Deinoccus group form dimers. We solved the crystal structures of the SSB protein from Thermus aquaticus (TaqSSB) and a deletion mutant of the protein and show the structure of their ssDNA binding domains to be similar to the structure of tetrameric SSBs. Two conformations accompanied by proline cis–trans isomerization are observed in the flexible C-terminal region. For the first time, we were able to trace 6 out of 10 amino acids at the C-terminus of an SSB protein. This highly conserved region is essential for interaction with other proteins and we show it to adopt an extended conformation devoid of secondary structure. A model for binding this region to the χ subunit of DNA polymerase III is proposed. It explains at a molecular level the reason for the ssb113 phenotype observed in Escherichia coli.
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Affiliation(s)
| | | | | | | | - Ute Curth
- To whom correspondence should be addressed. Tel: +49 511 532 3707; Fax: + 49 511 532 5966;
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30
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Coetzee A, Schierbeek B, Witte G, Curth U, Manstein DJ, Fedorov R. Improving data quality - without having to grow new crystals. Acta Crystallogr A 2005. [DOI: 10.1107/s0108767305093736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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31
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Fedorov R, Coetzee A, Witte G, Curth U, Manstein DJ. Structure of a dimeric single-stranded DNA binding protein from Thermus aquaticus. Acta Crystallogr A 2005. [DOI: 10.1107/s0108767305090550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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32
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Abstract
Sedimentation analysis in the analytical ultracentrifuge can be employed to detect macromolecular interactions. Whenever two molecules interact the mass of the resulting complex is increased and this is reflected in the sedimentation behavior. In this chapter we discuss how this phenomenon can be utilized to determine quantitative parameters of an interaction. An example, interaction of single-stranded DNA binding protein with a subunit of DNA polymerase III holoenzyme is given together with a thorough treatment of the relating theory and a description of evaluation algorithms.
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Affiliation(s)
- Claus Urbanke
- Department of Biophysical Chemistry, Medizinische Hochschule, Hannover, Germany
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33
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Abstract
The highly conserved bacterial single-stranded DNA-binding (SSB) proteins play an important role in DNA replication, repair and recombination and are essential for the survival of the cell. They are functional as tetramers, in which four OB(oligonucleotide/oligosaccharide binding)-folds act as DNA-binding domains. The protomer of the SSB protein from the extremely radiation-resistant organism Deinococcus radiodurans (DraSSB) has twice the size of the other bacterial SSB proteins and contains two OB-folds. Using analytical ultracentrifugation, we could show that DraSSB forms globular dimers with some protrusions. These DraSSB dimers can interact with two molecules of E.coli DNA polymerase III chi subunit. In fluorescence titrations with poly(dT) DraSSB bound 47-54 nt depending on the salt concentration, and fluorescence was quenched by more than 75%. A distinct low salt binding mode as for EcoSSB was not observed for DraSSB. Nucleic acid binding affinity, rate constant and association mechanism are quite similar for EcoSSB and DraSSB. In a complementation assay in E.coli, DraSSB took over the in vivo function of EcoSSB. With DraSSB behaving almost identical to EcoSSB the question remains open as to why dimeric SSB proteins have evolved in the Thermus group of bacteria.
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Affiliation(s)
| | | | - Ute Curth
- To whom correspondence should be addressed at Medizinische Hochschule Hannover, Zentrale Einrichtung für biophysikalisch-biochemische Verfahren, Carl-Neuberg-Strasse 1, D-30625 Hannover, Germany. Tel: +49 511 532 3707; Fax: +49 511 532 5966;
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34
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Witte G, Urbanke C, Curth U. DNA polymerase III chi subunit ties single-stranded DNA binding protein to the bacterial replication machinery. Nucleic Acids Res 2003; 31:4434-40. [PMID: 12888503 PMCID: PMC169888 DOI: 10.1093/nar/gkg498] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2003] [Revised: 05/28/2003] [Accepted: 06/05/2003] [Indexed: 11/13/2022] Open
Abstract
Single-stranded DNA binding (SSB) protein binds to single-stranded DNA (ssDNA) at the lagging strand of the replication fork in Escherichia coli cells. This protein is essential for the survival of the E.coli cell, presumably because it shields the ssDNA and holds it in a suitable conformation for replication by DNA polymerase III. In this study we undertook a biophysical analysis of the interaction between the SSB protein of E.coli and the chi subunit of DNA polymerase III. Using analytical ultracentrifugation we show that at low salt concentrations there is an increase in the stability in the physical interaction between chi and an EcoSSB/ssDNA complex when compared to that of chi to EcoSSB alone. This increase in stability disappeared in high salt conditions. The sedimentation of an EcoSSB protein lacking its C-terminal 26 amino acids remains unchanged in the presence of chi, showing that chi interacts specifically with the C-terminus of EcoSSB. In DNA melting experiments we demonstrate that chi specifically enhances the ssDNA stabilization by EcoSSB. Thus, the binding of EcoSSB to chi at the replication fork prevents premature dissociation of EcoSSB from the lagging strand and thereby enhances the processivity of DNA polymerase III.
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Affiliation(s)
- Gregor Witte
- Medizinische Hochschule, Zentrale Einrichtung für Biophysikalisch-Biochemische Verfahren, Carl Neuberg Strasse 1, D-30625 Hannover, Germany
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35
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Abstract
A single amino acid substitution (Y78R) at the dimer-dimer interface of homotetrameric single stranded DNA binding protein from E. coli (EcoSSB) renders the protein a stable dimer. This dimer can bind single-stranded DNA albeit with greatly reduced affinity. In vivo this dimeric SSB cannot replace homotetrameric EcoSSB. Amino acid changes at the rim of the dimer-dimer interface nearby (Q76K, Q76E) show an electrostatic interaction between a charged amino acid at position 76 and bound nucleic acid. In conclusion, nucleic acid binding to homotetrameric SSB must take place across both dimers to achieve functionally correct binding.
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36
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Genschel J, Curth U, Urbanke C. Interaction of E. coli single-stranded DNA binding protein (SSB) with exonuclease I. The carboxy-terminus of SSB is the recognition site for the nuclease. Biol Chem 2000; 381:183-92. [PMID: 10782989 DOI: 10.1515/bc.2000.025] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The 3'-5' single-stranded DNA(ssDNA) degrading exonuclease I of E. coli directly interacts with the E. coli ssDNA binding protein (EcoSSB). Analytical ultracentrifugation shows that all 4 carboxy-termini of an EcoSSB tetramer bind exonuclease I. Binding is weakened by increasing salt concentrations, indicating the involvement of the negatively charged amino acids of the carboxy-terminus of SSB. Mutant SSB proteins EcoSSBP176S (ssb-113) and EcoSSBF177C do not bindtoexonuclease I while EcoSSBG15D (ssb-3) does bind. In a co-precipitation assay we show that the absence of the lastten amino acids (PMDFDDDIPF) completely abolishes binding of EcoSSB to exonuclease I. The interaction does not depend on the presence of the correct amino-terminal DNA binding domain or the amino acid sequences between the DNA binding domain and the last ten amino acids. A synthetic peptide (WMDFDDDIPF), corresponding to the last nine amino acids of EcoSSB, specifically inhibits the interaction. Both EcoSSBP176S and EcoSSBF177C SSBs bind DNA similar to wild-type EcoSSB, indicating that the phenotype of ssb-113 is not an indication of altered DNA binding. The repair deficiency of either ssb-3 or ssb-113 strain can be complemented by overexpression of the respective other mutant.
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Affiliation(s)
- J Genschel
- Medizinische Hochschule Hannover, Biophysikalische Chemie, Hannover, Germany
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37
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Carlini L, Curth U, Kindler B, Urbanke C, Porter RD. Identification of amino acids stabilizing the tetramerization of the single stranded DNA binding protein from Escherichia coli. FEBS Lett 1998; 430:197-200. [PMID: 9688537 DOI: 10.1016/s0014-5793(98)00655-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Mutating the histidine at position 55 present at the subunit interface of the tetrameric E. coli single stranded DNA binding (SSB) protein to tyrosine or lysine leads to cells which are UV- and temperature-sensitive. The defects of both ssbH55Y (ssb-1) and ssbH55K can be overcome by increasing protein concentration, with the ssbH55K mutation producing a less stable, readily dissociating protein whose more severe replication and repair phenotypes were less easily ameliorated by protein amplification. In this study we selected and analyzed E. coli strains where the temperature sensitivity caused by the ssbH55K mutation was suppressed by spontaneous mutations that changed the glutamine at position 76 or 110 to leucine. Using guanidinium chloride denaturation monitored by sedimentation diffusion equilibrium experiments in the analytical ultracentrifuge, we demonstrate that the double mutant SSBH55KQ76L and SSBH55KQ110L proteins form more stable homotetramers as compared to the SSBH55K single mutant protein although they are less stable than wild-type SSB. Additionally, the single mutant proteins SSBQ76L and SSBQ110L form tetramers which are more resistant to guanidinium denaturation than wild-type SSB protein.
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Affiliation(s)
- L Carlini
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park 16802, USA
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38
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Webster G, Genschel J, Curth U, Urbanke C, Kang C, Hilgenfeld R. A common core for binding single-stranded DNA: structural comparison of the single-stranded DNA-binding proteins (SSB) from E. coli and human mitochondria. FEBS Lett 1997; 411:313-6. [PMID: 9271227 DOI: 10.1016/s0014-5793(97)00747-3] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The crystal structure of the DNA-binding domain of E. coli SSB (EcoSSB) has been determined to a resolution of 2.5 A. This is the first reported structure of a prokaryotic SSB. The structure of the DNA-binding domain of the E. coli protein is compared to that of the human mitochondrial SSB (HsmtSSB). In spite of the relatively low sequence identity between them, the two proteins display a high degree of structural similarity. EcoSSB crystallises with two dimers in the asymmetric unit, unlike HsmtSSB which contains only a dimer. This is probably a consequence of the different polypeptide chain lengths in the EcoSSB heterotetramer. Crucial differences in the dimer-dimer interface of EcoSSB may account for the inability of EcoSSB and HsmtSSB to form cross-species heterotetramers, in contrast to many bacterial SSBs.
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Affiliation(s)
- G Webster
- Department of Structural Biology and Crystallography, Institute of Molecular Biotechnology, Jena, Germany.
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39
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Yang C, Curth U, Urbanke C, Kang C. Crystal structure of human mitochondrial single-stranded DNA binding protein at 2.4 A resolution. Nat Struct Biol 1997; 4:153-7. [PMID: 9033597 DOI: 10.1038/nsb0297-153] [Citation(s) in RCA: 142] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We solved the crystal structure of the homotetrameric single-stranded DNA binding (SSB) protein from human mitochondria at a resolution of 2.4 A. The tetramer is formed by two dimers interacting head-to-head and shows D2 symmetry. Sequence-related tetrameric SSB proteins occur in prokaryotes and eukaryotic mitochondria; this is the first report of an atomic resolution structure of this type of protein. Using biochemical data and analysis of sequence homologies, we were able to correlate the functional properties with structure. We propose that ssDNA wraps around the tetrameric HsmtSSB protein through electropositive channels guided by flexible loops.
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Affiliation(s)
- C Yang
- Department of Biochemistry and Biophysics, Washington State University, Pullman 99164-4660, USA
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40
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Curth U, Genschel J, Urbanke C, Greipel J. In vitro and in vivo function of the C-terminus of Escherichia coli single-stranded DNA binding protein. Nucleic Acids Res 1996; 24:2706-11. [PMID: 8759000 PMCID: PMC145992 DOI: 10.1093/nar/24.14.2706] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
We constructed several deletion mutants of Escherichia coli single-stranded DNA binding protein (EcoSSB) lacking different parts of the C-terminal region. This region of EcoSSB is composed of two parts: a glycine and proline-rich sequence of approximately 60 amino acids followed by an acidic region of the last 10 amino acids which is highly conserved among the bacterial SSB proteins. The single-stranded DNA binding protein of human mitochondria (HsmtSSB) lacks a region homologous to the C-terminal third of EcoSSB. Therefore, we also investigated a chimeric protein consisting of the complete sequence of the human mitochondrial single-stranded DNA binding protein (HsmtSSB) and the C-terminal third of EcoSSB. Fluorescence titrations and DNA-melting curves showed that the C-terminal third of EcoSSB is not essential for DNA-binding in vitro. The affinity for single-stranded DNA and RNA is even increased by the removal of the last 10 amino acids. Consequently, the nucleic acid binding affinity of HsmtSSB is reduced by the addition of the C-terminus of EcoSSB. All mutant proteins lacking the last 10 amino acids are unable to substitute wild-type EcoSSB in vivo. Thus, while the nucleic acid binding properties do not depend on an intact C-terminus, this region is essential for in vivo function. Although the DNA binding properties of HsmtSSB and EcoSSB are quite similar, HsmtSSB does not function in E.coli. This failure cannot be overcome by fusing the C-terminal third of EcoSSB to HsmtSSB. Thus differences in the N-terminal parts of both proteins must be responsible for this incompatibility. None of the mutants was defective in tetramerization. However, mixed tetramers could only be formed by proteins containing the same N-terminal part. This reflects structural differences between the N-terminal parts of HsmtSSB and EcoSSB. These results indicate that the region of the last 10 amino acids, which is highly conserved among bacterial SSB proteins, is involved in essential protein-protein interactions in the E.coli cell.
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Affiliation(s)
- U Curth
- Medizinische Hochschule, Hannover, Germany
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41
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Abstract
Conformation and stability of EcoSSB, a single-stranded DNA binding protein encoded by Escherichia coli, were analyzed by circular dichroism and fluorescence measurements. From CD measurements at pH 7.5, EcoSSB can be classified as a protein with high alpha-helix and beta-sheet content. The hydrophobicity of the environment of the tryptophan residues of the native protein is only marginally increased in comparison to the unfolded protein. The GdnHCl induced unfolding curves measured by CD and fluorescence are coincident and sigmoidal and show a monophasic transition. The stability of EcoSSB is concentration dependent and the unfolding behavior can be described as a two-state transition from the folded tetrameter to unfolded monomers. The mean values of free energy of dissociation and unfolding delta GH2O mu are between 173 and 177 kJ.mol-1 and the mean half concentration c1/2 of GdnHCl of the transition curves are about 1.5 M and 1.7 M for protein concentrations of 0.1 mg.ml-1 and 0.5 mg.ml-1, respectively.
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Affiliation(s)
- R Misselwitz
- Institute of Biochemistry Medical Faculty (Charité), Humboldt University Berlin, Federal Republic of Germany
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42
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Curth U, Urbanke C, Greipel J, Gerberding H, Tiranti V, Zeviani M. Single-stranded-DNA-binding proteins from human mitochondria and Escherichia coli have analogous physicochemical properties. Eur J Biochem 1994; 221:435-43. [PMID: 8168532 DOI: 10.1111/j.1432-1033.1994.tb18756.x] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The gene for the mature human mitochondrial single-stranded-DNA binding protein (HsmtSSB) has been transferred into a protein-overproducing vector and expressed in Escherichia coli. The protein was purified to homogeneity and its physicochemical properties were investigated. From sequence comparison, HsmtSSB shows some similarities to the N-terminal part of the single-stranded DNA-binding protein (SSB) from E. coli (EcoSSB). Hydrodynamic measurements show the protein to be tetrameric and give a sedimentation coefficient of 4.1 S corresponding to a C-terminally shortened EcoSSB. Electron-microscopic images of the free protein show a globular tetrahedral structure. Binding of poly(desoxythymidylic acid) [poly(dT)] leads to a reduction of the tryptophan fluorescence of the protein up to 96%. Fluorescence titrations with poly(dT) show apparent binding-site sizes of 50-70 nucleotides/tetramer between 0.05 M and 2 M NaCl. Binding to poly(dT) proceeds in a nearly diffusion-controlled reaction with an association-rate constant kass of 4 x 10(8) M-1s-1. The rate-limiting step is the formation of a transient complex where less than four binding sites on the protein are involved and the reshuffling of the protein on the linear matrix is fast. Electron microscopy of the complex with poly(dT) using negative staining shows a nearly random distribution of the protein between the individual poly(dT) strands. This leads to the conclusion that the binding cooperativity is low (omega < 150). The two tryptophans of HsmtSSB were replaced by threonine and tyrosine. The environment of both residues is influenced by nucleic acid binding with mutations of Trp68 strongly reducing the DNA-binding affinity of the protein.
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Affiliation(s)
- U Curth
- Medizinische Hochschule, Zentrum Biochemie, Hannover, Germany
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43
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Carlini LE, Porter RD, Curth U, Urbanke C. Viability and preliminary in vivo characterization of site-directed mutants of Escherichia coli single-stranded DNA-binding protein. Mol Microbiol 1993; 10:1067-75. [PMID: 7934857 DOI: 10.1111/j.1365-2958.1993.tb00977.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Site-directed mutations involving selected amino acids of Escherichia coli single-stranded DNA-binding protein (SSB) were tested for their in vivo functionality when introduced into a chromosomal ssb deletion strain on a plasmid. All mutants complemented the ssb deletion for viability when present on a pSC101 derivative. The generation time with ssbW54S doubled in comparison to the ssb+ control, and both the ssbW54S- and ssbH55K-containing strains exhibited temperature sensitivity. ssbH55K, ssbW54S, ssbW88T, and ssbH55Y (ssb-1) strains displayed reduced survival to ultraviolet irradiation, while ssbW40T and ssbF60L strains were comparable to the ssb+ control strain. This study represents the first investigation of the in vivo properties of ssb mutations constructed for in vitro analysis of DNA binding by SSB.
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Affiliation(s)
- L E Carlini
- Department of Molecular and Cell Biology, Pennsylvania State University, University Park 16802
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44
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Curth U, Greipel J, Urbanke C, Maass G. Multiple binding modes of the single-stranded DNA binding protein from Escherichia coli as detected by tryptophan fluorescence and site-directed mutagenesis. Biochemistry 1993; 32:2585-91. [PMID: 8448116 DOI: 10.1021/bi00061a016] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
We have systematically substituted the four tryptophan residues of the single-stranded DNA binding protein from Escherichia coli (EcoSSB) by polar (serine or threonine) and aromatic (tyrosine or phenylalanine) amino acids. The resulting mutants with either single amino acid exchanges or triple substitutions are all active in ssDNA binding, though in some cases with reduced affinities. Measurements of the fluorescence of the mutated EcoSSBs show that there is no interaction between the four different tryptophan residues. We analyzed the ssDNA binding of the mutant proteins by fluorescence titrations. At 0.3 M NaCl ("high salt"), all singly substituted proteins bind to poly(dT) in a manner comparable to wild-type EcoSSB, covering 65 nucleotides with 1 EcoSSB tetramer. W54S mutant protein is an exception since even at 0.3 M NaCl it covers approximately 35 nucleotides, a behavior which is typical of salt concentrations below 10 mM NaCl ("low salt"). From this observation, it is inferred that tryptophan-54 is involved in a direct interaction with the ssDNA favoring the "high-salt" binding mode. All mutant proteins lacking tryptophan-54 but possessing tryptophan-88 at "low-salt" concentrations show a nonmonotonous behavior in the fluorescence titrations. This behavior can be interpreted assuming a model of cooperative binding of EcoSSB to poly(dT) with two different binding site sizes (n approximately 27 and n approximately 33) and different binding affinities. A quantitative treatment of the problem of multiple binding modes in the interaction of a multidentate ligand with a linear polymer is applied to these titrations.
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Affiliation(s)
- U Curth
- Medizinische Hochschule, Abteilung Biophysikalische Chemie, Hannover, FRG
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Curth U, Bayer I, Greipel J, Mayer F, Urbanke C, Maass G. Amino acid 55 plays a central role in tetramerization and function of Escherichia coli single-stranded DNA binding protein. Eur J Biochem 1991; 196:87-93. [PMID: 2001710 DOI: 10.1111/j.1432-1033.1991.tb15789.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The histidine at position 55 of the amino acid sequence of the Escherichia coli single-stranded DNA binding protein was replaced by tyrosine, glutamic acid, lysine, phenylalanine, and isoleucine. The properties of the mutant proteins were determined using analytical ultracentrifugation, NMR spectroscopy, gel filtration, and fluorimetric detection of their single-stranded DNA binding ability. While the phenylalanine and isoleucine substitutions did not change the properties of the protein measurably, tyrosine and lysine mutants dissociate into subunits and loose some of their binding affinity for poly(dT). For the lysine mutant we show by electron microscopy that the protein, although fully dissociated and possibly denatured in the free state, binds to poly(dT) as a tetramer indistinguishable from the wild-type protein. The process of tetramerization as observed via single-stranded DNA binding ability is composed of a variety of steps ranging in time from some milliseconds to several hours; it probably involves several forms of dissociated and non-native protein.
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Affiliation(s)
- U Curth
- Medizinische Hochschule, Zentrum Biochemie, Hannover, Federal Republic of Germany
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