1
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Liu B, Niu X, Deng Y, Zhang Z, Wang Y, Gao X, Liang H, Li Z, Wang Q, Cheng Y, Chen Q, Huang S, Pan Y, Su M, Lin X, Niu C, Chen Y, Yang W, Zhang Y, Yan Q, He J, Zhao J, Chen L, Xiong X. An unconventional VH1-2 antibody tolerates escape mutations and shows an antigenic hotspot on SARS-CoV-2 spike. Cell Rep 2024; 43:114265. [PMID: 38805396 DOI: 10.1016/j.celrep.2024.114265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 11/29/2023] [Accepted: 05/07/2024] [Indexed: 05/30/2024] Open
Abstract
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S) protein continues to evolve antigenically, impacting antibody immunity. D1F6, an affinity-matured non-stereotypic VH1-2 antibody isolated from a patient infected with the SARS-CoV-2 ancestral strain, effectively neutralizes most Omicron variants tested, including XBB.1.5. We identify that D1F6 in the immunoglobulin G (IgG) form is able to overcome the effect of most Omicron mutations through its avidity-enhanced multivalent S-trimer binding. Cryo-electron microscopy (cryo-EM) and biochemical analyses show that three simultaneous epitope mutations are generally needed to substantially disrupt the multivalent S-trimer binding by D1F6 IgG. Antigenic mutations at spike positions 346, 444, and 445, which appeared in the latest variants, have little effect on D1F6 binding individually. However, these mutations are able to act synergistically with earlier Omicron mutations to impair neutralization by affecting the interaction between D1F6 IgG and the S-trimer. These results provide insight into the mechanism by which accumulated antigenic mutations facilitate evasion of affinity-matured antibodies.
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Affiliation(s)
- Banghui Liu
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Xuefeng Niu
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
| | - Yijun Deng
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Zhaoyong Zhang
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Yanqun Wang
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Xijie Gao
- Key Laboratory of Biological Targeting Diagnosis, Therapy and Rehabilitation of Guangdong Higher Education Institutes, The Fifth Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Huan Liang
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Zimu Li
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Qian Wang
- Guangzhou Laboratory & Bioland Laboratory, Guangzhou, China
| | - Yuanyi Cheng
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Qiuluan Chen
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health - Guangdong Laboratory), Guangzhou, China
| | - Shuangshuang Huang
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Yingxian Pan
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Mengzhen Su
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China; University of Science and Technology of China, Hefei, China
| | - Xiancheng Lin
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Chuanying Niu
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China; University of Science and Technology of China, Hefei, China
| | - Yinglin Chen
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Wenyi Yang
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Yudi Zhang
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China; University of Chinese Academy of Sciences, Beijing, China
| | - Qihong Yan
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Jun He
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Jincun Zhao
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
| | - Ling Chen
- Guangzhou Laboratory & Bioland Laboratory, Guangzhou, China.
| | - Xiaoli Xiong
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China.
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2
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Lublin V, Kauffmann B, Engilberge S, Durola F, Gounel S, Bichon S, Jean C, Mano N, Giraud MF, Chavas L, Thureau A, Thompson A, Stines-Chaumeil C. Does Acinetobacter calcoaceticus glucose dehydrogenase produce self-damaging H2O2? Biosci Rep 2024; 44:BSR20240102. [PMID: 38687614 PMCID: PMC11130540 DOI: 10.1042/bsr20240102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 04/25/2024] [Accepted: 04/30/2024] [Indexed: 05/02/2024] Open
Abstract
The soluble glucose dehydrogenase (sGDH) from Acinetobacter calcoaceticus has been widely studied and is used, in biosensors, to detect the presence of glucose, taking advantage of its high turnover and insensitivity to molecular oxygen. This approach, however, presents two drawbacks: the enzyme has broad substrate specificity (leading to imprecise blood glucose measurements) and shows instability over time (inferior to other oxidizing glucose enzymes). We report the characterization of two sGDH mutants: the single mutant Y343F and the double mutant D143E/Y343F. The mutants present enzyme selectivity and specificity of 1.2 (Y343F) and 5.7 (D143E/Y343F) times higher for glucose compared with that of the wild-type. Crystallographic experiments, designed to characterize these mutants, surprisingly revealed that the prosthetic group PQQ (pyrroloquinoline quinone), essential for the enzymatic activity, is in a cleaved form for both wild-type and mutant structures. We provide evidence suggesting that the sGDH produces H2O2, the level of production depending on the mutation. In addition, spectroscopic experiments allowed us to follow the self-degradation of the prosthetic group and the disappearance of sGDH's glucose oxidation activity. These studies suggest that the enzyme is sensitive to its self-production of H2O2. We show that the premature aging of sGDH can be slowed down by adding catalase to consume the H2O2 produced, allowing the design of a more stable biosensor over time. Our research opens questions about the mechanism of H2O2 production and the physiological role of this activity by sGDH.
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Affiliation(s)
- Victoria Lublin
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
- Synchrotron SOLEIL (CNRS - CEA), Saint-Aubin, France
| | - Brice Kauffmann
- Institut Européen de Chimie et Biologie (IECB), Univ. Bordeaux, CNRS, INSERM, US1, UAR 3033, Pessac, France
| | - Sylvain Engilberge
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale (IBS), 71 avenue des Martyrs, Grenoble 38044, France
| | - Fabien Durola
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
| | - Sébastien Gounel
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
| | - Sabrina Bichon
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
| | - Cloée Jean
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
| | - Nicolas Mano
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
| | - Marie-France Giraud
- Institute of Chemistry and Biology of Membranes and Nano-objects (CBMN), Pessac, France
| | | | | | | | - Claire Stines-Chaumeil
- Centre de Recherche Paul Pascal (CRPP), University Bordeaux, CNRS, UMR 5031, Pessac, France
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3
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Bruce HA, Singer AU, Filippova EV, Blazer LL, Adams JJ, Enderle L, Ben‐David M, Radley EH, Mao DYL, Pau V, Orlicky S, Sicheri F, Kurinov I, Atwell S, Kossiakoff AA, Sidhu SS. Engineered antigen-binding fragments for enhanced crystallization of antibody:antigen complexes. Protein Sci 2024; 33:e4824. [PMID: 37945533 PMCID: PMC10731619 DOI: 10.1002/pro.4824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 10/09/2023] [Accepted: 10/28/2023] [Indexed: 11/12/2023]
Abstract
The atomic-resolution structural information that X-ray crystallography can provide on the binding interface between a Fab and its cognate antigen is highly valuable for understanding the mechanism of interaction. However, many Fab:antigen complexes are recalcitrant to crystallization, making the endeavor a considerable effort with no guarantee of success. Consequently, there have been significant steps taken to increase the likelihood of Fab:antigen complex crystallization by altering the Fab framework. In this investigation, we applied the surface entropy reduction strategy coupled with phage-display technology to identify a set of surface substitutions that improve the propensity of a human Fab framework to crystallize. In addition, we showed that combining these surface substitutions with previously reported Crystal Kappa and elbow substitutions results in an extraordinary improvement in Fab and Fab:antigen complex crystallizability, revealing a strong synergistic relationship between these sets of substitutions. Through comprehensive Fab and Fab:antigen complex crystallization screenings followed by structure determination and analysis, we defined the roles that each of these substitutions play in facilitating crystallization and how they complement each other in the process.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Daniel Y. L. Mao
- Lunenfeld‐Tanenbaum Research InstituteSinai Health SystemTorontoCanada
| | - Victor Pau
- Lunenfeld‐Tanenbaum Research InstituteSinai Health SystemTorontoCanada
| | - Stephen Orlicky
- Lunenfeld‐Tanenbaum Research InstituteSinai Health SystemTorontoCanada
| | - Frank Sicheri
- Lunenfeld‐Tanenbaum Research InstituteSinai Health SystemTorontoCanada
- Departments of Biochemistry and Molecular GeneticsUniversity of TorontoOntarioCanada
| | | | | | - Anthony A. Kossiakoff
- Department of Biochemistry and Molecular BiologyUniversity of ChicagoChicagoIllinoisUSA
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4
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Navas-Yuste S, de la Paz K, Querol-García J, Gómez-Quevedo S, Rodríguez de Córdoba S, Fernández FJ, Vega MC. The structure of Leptospira interrogans GAPDH sheds light into an immunoevasion factor that can target the anaphylatoxin C5a of innate immunity. Front Immunol 2023; 14:1190943. [PMID: 37409124 PMCID: PMC10318897 DOI: 10.3389/fimmu.2023.1190943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 05/30/2023] [Indexed: 07/07/2023] Open
Abstract
Leptospirosis is a neglected worldwide zoonosis involving farm animals and domestic pets caused by the Gram-negative spirochete Leptospira interrogans. This bacterium deploys a variety of immune evasive mechanisms, some of them targeted at the complement system of the host's innate immunity. In this work, we have solved the X-ray crystallographic structure of L. interrogans glyceraldehyde-3-phosphate dehydrogenase (GAPDH) to 2.37-Å resolution, a glycolytic enzyme that has been shown to exhibit moonlighting functions that potentiate infectivity and immune evasion in various pathogenic organisms. Besides, we have characterized the enzyme's kinetic parameters toward the cognate substrates and have proven that the two natural products anacardic acid and curcumin are able to inhibit L. interrogans GAPDH at micromolar concentration through a noncompetitive inhibition modality. Furthermore, we have established that L. interrogans GAPDH can interact with the anaphylatoxin C5a of human innate immunity in vitro using bio-layer interferometry and a short-range cross-linking reagent that tethers free thiol groups in protein complexes. To shed light into the interaction between L. interrogans GAPDH and C5a, we have also carried out cross-link guided protein-protein docking. These results suggest that L. interrogans could be placed in the growing list of bacterial pathogens that exploit glycolytic enzymes as extracellular immune evasive factors. Analysis of the docking results indicates a low affinity interaction that is consistent with previous evidence, including known binding modes of other α-helical proteins with GAPDH. These findings allow us to propose L. interrogans GAPDH as a potential immune evasive factor targeting the complement system.
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Affiliation(s)
- Sergio Navas-Yuste
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Karla de la Paz
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
- Abvance Biotech Srl, Madrid, Spain
| | - Javier Querol-García
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
- Abvance Biotech Srl, Madrid, Spain
| | - Sara Gómez-Quevedo
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
- Universidad Europea, Madrid, Spain
| | - Santiago Rodríguez de Córdoba
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
- Centro de Investigación Biomedica en Red sobre Enfermedades Raras (CIBERER), Madrid, Spain
| | - Francisco J. Fernández
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
- Abvance Biotech Srl, Madrid, Spain
| | - M. Cristina Vega
- Centro de Investigaciones Biológicas Margarita Salas, Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
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5
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Schulte T, Panas MD, Han X, Williams L, Kedersha N, Fleck JS, Tan TJC, Dopico XC, Olsson A, Morro AM, Hanke L, Nilvebrant J, Giang KA, Nygren PÅ, Anderson P, Achour A, McInerney GM. Caprin-1 binding to the critical stress granule protein G3BP1 is influenced by pH. Open Biol 2023; 13:220369. [PMID: 37161291 PMCID: PMC10170197 DOI: 10.1098/rsob.220369] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 03/28/2023] [Indexed: 05/11/2023] Open
Abstract
G3BP is the central node within stress-induced protein-RNA interaction networks known as stress granules (SGs). The SG-associated proteins Caprin-1 and USP10 bind mutually exclusively to the NTF2 domain of G3BP1, promoting and inhibiting SG formation, respectively. Herein, we present the crystal structure of G3BP1-NTF2 in complex with a Caprin-1-derived short linear motif (SLiM). Caprin-1 interacts with His-31 and His-62 within a third NTF2-binding site outside those covered by USP10, as confirmed using biochemical and biophysical-binding assays. Nano-differential scanning fluorimetry revealed reduced thermal stability of G3BP1-NTF2 at acidic pH. This destabilization was counterbalanced significantly better by bound USP10 than Caprin-1. The G3BP1/USP10 complex immunoprecipated from human U2OS cells was more resistant to acidic buffer washes than G3BP1/Caprin-1. Acidification of cellular condensates by approximately 0.5 units relative to the cytosol was detected by ratiometric fluorescence analysis of pHluorin2 fused to G3BP1. Cells expressing a Caprin-1/FGDF chimera with higher G3BP1-binding affinity had reduced Caprin-1 levels and slightly reduced condensate sizes. This unexpected finding may suggest that binding of the USP10-derived SLiM to NTF2 reduces the propensity of G3BP1 to enter condensates.
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Affiliation(s)
- Tim Schulte
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, and Division of Infectious Diseases, Karolinska University Hospital, Stockholm, 171 77, Sweden
| | - Marc D. Panas
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Xiao Han
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, and Division of Infectious Diseases, Karolinska University Hospital, Stockholm, 171 77, Sweden
| | - Lucy Williams
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Nancy Kedersha
- Division of Rheumatology, Immunity, and Inflammation, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Harvard Medical School Initiative for RNA Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Jonas Simon Fleck
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, and Division of Infectious Diseases, Karolinska University Hospital, Stockholm, 171 77, Sweden
| | - Timothy J. C. Tan
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Xaquin Castro Dopico
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Anders Olsson
- Protein Expression and Characterization, AlbaNova University Center, Royal Institute of Technology, 114 21, Stockholm
| | - Ainhoa Moliner Morro
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Leo Hanke
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Johan Nilvebrant
- Division of Protein Engineering, Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, AlbaNova University Center, Royal Institute of Technology, 114 21, Stockholm
- Science for Life Laboratory, Tomtebodavägen 23A, 171 65, Sweden
| | - Kim Anh Giang
- Division of Protein Engineering, Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, AlbaNova University Center, Royal Institute of Technology, 114 21, Stockholm
- Science for Life Laboratory, Tomtebodavägen 23A, 171 65, Sweden
| | - Per-Åke Nygren
- Division of Protein Engineering, Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, AlbaNova University Center, Royal Institute of Technology, 114 21, Stockholm
- Science for Life Laboratory, Tomtebodavägen 23A, 171 65, Sweden
| | - Paul Anderson
- Division of Rheumatology, Immunity, and Inflammation, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Harvard Medical School Initiative for RNA Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Adnane Achour
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, and Division of Infectious Diseases, Karolinska University Hospital, Stockholm, 171 77, Sweden
| | - Gerald M. McInerney
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
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6
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Yu H, Liu B, Zhang Y, Gao X, Wang Q, Xiang H, Peng X, Xie C, Wang Y, Hu P, Shi J, Shi Q, Zheng P, Feng C, Tang G, Liu X, Guo L, Lin X, Li J, Liu C, Huang Y, Yang N, Chen Q, Li Z, Su M, Yan Q, Pei R, Chen X, Liu L, Hu F, Liang D, Ke B, Ke C, Li F, He J, Wang M, Chen L, Xiong X, Tang X. Somatically hypermutated antibodies isolated from SARS-CoV-2 Delta infected patients cross-neutralize heterologous variants. Nat Commun 2023; 14:1058. [PMID: 36828833 PMCID: PMC9951844 DOI: 10.1038/s41467-023-36761-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 02/10/2023] [Indexed: 02/26/2023] Open
Abstract
SARS-CoV-2 Omicron variants feature highly mutated spike proteins with extraordinary abilities in evading antibodies isolated earlier in the pandemic. Investigation of memory B cells from patients primarily with breakthrough infections with the Delta variant enables isolation of a number of neutralizing antibodies cross-reactive to heterologous variants of concern (VOCs) including Omicron variants (BA.1-BA.4). Structural studies identify altered complementarity determining region (CDR) amino acids and highly unusual heavy chain CDR2 insertions respectively in two representative cross-neutralizing antibodies-YB9-258 and YB13-292. These features are putatively introduced by somatic hypermutation and they are heavily involved in epitope recognition to broaden neutralization breadth. Previously, insertions/deletions were rarely reported for antiviral antibodies except for those induced by HIV-1 chronic infections. These data provide molecular mechanisms for cross-neutralization of heterologous SARS-CoV-2 variants by antibodies isolated from Delta variant infected patients with implications for future vaccination strategy.
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Affiliation(s)
- Haisheng Yu
- Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, China.
| | - Banghui Liu
- The State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Center for Cell Lineage and Development, Guangzhou Institutes of Biomedicine and Health, the Chinese Academy of Sciences, Guangzhou, China
| | - Yudi Zhang
- The State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Center for Cell Lineage and Development, Guangzhou Institutes of Biomedicine and Health, the Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xijie Gao
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health-Guangdong Laboratory), Guangzhou, China
| | - Qian Wang
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Haitao Xiang
- BGI-Shenzhen, Shenzhen, China
- China National GeneBank, BGI-Shenzhen, Shenzhen, China
| | - Xiaofang Peng
- Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, China
| | - Caixia Xie
- BGI-Shenzhen, Shenzhen, China
- China National GeneBank, BGI-Shenzhen, Shenzhen, China
| | - Yaping Wang
- Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, China
| | - Peiyu Hu
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health-Guangdong Laboratory), Guangzhou, China
- Guangzhou Laboratory, Guangzhou International Bio Island, Guangzhou, China
| | - Jingrong Shi
- Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, China
| | - Quan Shi
- BGI-Shenzhen, Shenzhen, China
- China National GeneBank, BGI-Shenzhen, Shenzhen, China
| | - Pingqian Zheng
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health-Guangdong Laboratory), Guangzhou, China
- Guangzhou Laboratory, Guangzhou International Bio Island, Guangzhou, China
| | - Chengqian Feng
- Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, China
| | - Guofang Tang
- Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, China
| | - Xiaopan Liu
- BGI-Shenzhen, Shenzhen, China
- China National GeneBank, BGI-Shenzhen, Shenzhen, China
| | - Liliangzi Guo
- Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, China
| | - Xiumei Lin
- BGI-Shenzhen, Shenzhen, China
- China National GeneBank, BGI-Shenzhen, Shenzhen, China
| | - Jiaojiao Li
- Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, China
| | - Chuanyu Liu
- BGI-Shenzhen, Shenzhen, China
- China National GeneBank, BGI-Shenzhen, Shenzhen, China
| | - Yaling Huang
- BGI-Shenzhen, Shenzhen, China
- China National GeneBank, BGI-Shenzhen, Shenzhen, China
| | - Naibo Yang
- BGI-Shenzhen, Shenzhen, China
- China National GeneBank, BGI-Shenzhen, Shenzhen, China
| | - Qiuluan Chen
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health-Guangdong Laboratory), Guangzhou, China
| | - Zimu Li
- The State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Center for Cell Lineage and Development, Guangzhou Institutes of Biomedicine and Health, the Chinese Academy of Sciences, Guangzhou, China
| | - Mengzhen Su
- The State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Center for Cell Lineage and Development, Guangzhou Institutes of Biomedicine and Health, the Chinese Academy of Sciences, Guangzhou, China
- University of Science and Technology of China, Hefei, Anhui, China
| | - Qihong Yan
- The State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Center for Cell Lineage and Development, Guangzhou Institutes of Biomedicine and Health, the Chinese Academy of Sciences, Guangzhou, China
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Rongjuan Pei
- State Key Laboratory of Virology, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Xinwen Chen
- Guangzhou Laboratory, Guangzhou International Bio Island, Guangzhou, China
- State Key Laboratory of Virology, Center for Biosafety Mega-Science, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, China
| | - Longqi Liu
- BGI-Shenzhen, Shenzhen, China
- China National GeneBank, BGI-Shenzhen, Shenzhen, China
| | - Fengyu Hu
- Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, China
| | - Dan Liang
- Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, China
| | - Bixia Ke
- Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, China
| | - Changwen Ke
- Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, China.
| | - Feng Li
- Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, China.
| | - Jun He
- The State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Center for Cell Lineage and Development, Guangzhou Institutes of Biomedicine and Health, the Chinese Academy of Sciences, Guangzhou, China.
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health-Guangdong Laboratory), Guangzhou, China.
| | - Meiniang Wang
- BGI-Shenzhen, Shenzhen, China.
- China National GeneBank, BGI-Shenzhen, Shenzhen, China.
| | - Ling Chen
- Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, China.
- The State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Center for Cell Lineage and Development, Guangzhou Institutes of Biomedicine and Health, the Chinese Academy of Sciences, Guangzhou, China.
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health-Guangdong Laboratory), Guangzhou, China.
- Guangzhou Laboratory, Guangzhou International Bio Island, Guangzhou, China.
| | - Xiaoli Xiong
- The State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Center for Cell Lineage and Development, Guangzhou Institutes of Biomedicine and Health, the Chinese Academy of Sciences, Guangzhou, China.
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health-Guangdong Laboratory), Guangzhou, China.
| | - Xiaoping Tang
- Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, China.
- Guangzhou Laboratory, Guangzhou International Bio Island, Guangzhou, China.
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7
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Yang H, Kim K, Li S, Pacheco J, Chen XS. Structural basis of sequence-specific RNA recognition by the antiviral factor APOBEC3G. Nat Commun 2022; 13:7498. [PMID: 36470880 PMCID: PMC9722718 DOI: 10.1038/s41467-022-35201-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 11/22/2022] [Indexed: 12/12/2022] Open
Abstract
An essential step in restricting HIV infectivity by the antiviral factor APOBEC3G is its incorporation into progeny virions via binding to HIV RNA. However, the mechanism of APOBEC3G capturing viral RNA is unknown. Here, we report crystal structures of a primate APOBEC3G bound to different types of RNAs, revealing that APOBEC3G specifically recognizes unpaired 5'-AA-3' dinucleotides, and to a lesser extent, 5'-GA-3' dinucleotides. APOBEC3G binds to the common 3'A in the AA/GA motifs using an aromatic/hydrophobic pocket in the non-catalytic domain. It binds to the 5'A or 5'G in the AA/GA motifs using an aromatic/hydrophobic groove conformed between the non-catalytic and catalytic domains. APOBEC3G RNA binding property is distinct from that of the HIV nucleocapsid protein recognizing unpaired guanosines. Our findings suggest that the sequence-specific RNA recognition is critical for APOBEC3G virion packaging and restricting HIV infectivity.
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Affiliation(s)
- Hanjing Yang
- Molecular and Computational Biology, Departments of Biological Sciences and Chemistry, Los Angeles, CA 90089 USA
| | - Kyumin Kim
- Molecular and Computational Biology, Departments of Biological Sciences and Chemistry, Los Angeles, CA 90089 USA
| | - Shuxing Li
- Molecular and Computational Biology, Departments of Biological Sciences and Chemistry, Los Angeles, CA 90089 USA ,grid.42505.360000 0001 2156 6853Center of Excellence in NanoBiophysics, University of Southern California, Los Angeles, CA 90089 USA
| | - Josue Pacheco
- Molecular and Computational Biology, Departments of Biological Sciences and Chemistry, Los Angeles, CA 90089 USA
| | - Xiaojiang S. Chen
- Molecular and Computational Biology, Departments of Biological Sciences and Chemistry, Los Angeles, CA 90089 USA ,grid.42505.360000 0001 2156 6853Center of Excellence in NanoBiophysics, University of Southern California, Los Angeles, CA 90089 USA ,grid.42505.360000 0001 2156 6853Genetic, Molecular and Cellular Biology Program, Keck School of Medicine, Los Angeles, CA 90033 USA ,grid.42505.360000 0001 2156 6853Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90033 USA
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8
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Schulte T, Chaves-Sanjuan A, Mazzini G, Speranzini V, Lavatelli F, Ferri F, Palizzotto C, Mazza M, Milani P, Nuvolone M, Vogt AC, Vogel M, Palladini G, Merlini G, Bolognesi M, Ferro S, Zini E, Ricagno S. Cryo-EM structure of ex vivo fibrils associated with extreme AA amyloidosis prevalence in a cat shelter. Nat Commun 2022; 13:7041. [PMID: 36396658 PMCID: PMC9672049 DOI: 10.1038/s41467-022-34743-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 11/07/2022] [Indexed: 11/18/2022] Open
Abstract
AA amyloidosis is a systemic disease characterized by deposition of misfolded serum amyloid A protein (SAA) into cross-β amyloid in multiple organs in humans and animals. AA amyloidosis occurs at high SAA serum levels during chronic inflammation. Prion-like transmission was reported as possible cause of extreme AA amyloidosis prevalence in captive animals, e.g. 70% in cheetah and 57-73% in domestic short hair (DSH) cats kept in zoos and shelters, respectively. Herein, we present the 3.3 Å cryo-EM structure of AA amyloid extracted post-mortem from the kidney of a DSH cat with renal failure, deceased in a shelter with extreme disease prevalence. The structure reveals a cross-β architecture assembled from two 76-residue long proto-filaments. Despite >70% sequence homology to mouse and human SAA, the cat SAA variant adopts a distinct amyloid fold. Inclusion of an eight-residue insert unique to feline SAA contributes to increased amyloid stability. The presented feline AA amyloid structure is fully compatible with the 99% identical amino acid sequence of amyloid fragments of captive cheetah.
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Affiliation(s)
- Tim Schulte
- Institute of Molecular and Translational Cardiology, IRCCS Policlinico San Donato, 20097, Milan, Italy
| | - Antonio Chaves-Sanjuan
- Department of Biosciences, Università degli Studi di Milano, Milan, Italy
- Pediatric Research Center Fondazione R.E. Invernizzi and NOLIMITS Center, Università degli Studi di Milano, Milan, Italy
| | - Giulia Mazzini
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Amyloidosis Research and Treatment Center, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | | | | | - Filippo Ferri
- AniCura Istituto Veterinario Novara, Strada Provinciale 9, 28060, Granozzo con Monticello, Novara, Italy
| | - Carlo Palizzotto
- AniCura Istituto Veterinario Novara, Strada Provinciale 9, 28060, Granozzo con Monticello, Novara, Italy
| | - Maria Mazza
- Istituto Zooprofilattico Sperimentale del Piemonte Liguria e Valle d'Aosta, S.C. Diagnostica Specialistica, Via Bologna 148, 10154, Torino, Italy
| | - Paolo Milani
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Amyloidosis Research and Treatment Center, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Mario Nuvolone
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Amyloidosis Research and Treatment Center, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Anne-Cathrine Vogt
- Department for BioMedical Research (DBMR), University of Bern, 3008, Bern, Switzerland
- Department of Rheumatology and Immunology, University Hospital Bern, 3010, Bern, Switzerland
| | - Monique Vogel
- Department for BioMedical Research (DBMR), University of Bern, 3008, Bern, Switzerland
- Department of Rheumatology and Immunology, University Hospital Bern, 3010, Bern, Switzerland
| | - Giovanni Palladini
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Amyloidosis Research and Treatment Center, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Giampaolo Merlini
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Amyloidosis Research and Treatment Center, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Martino Bolognesi
- Department of Biosciences, Università degli Studi di Milano, Milan, Italy
- Pediatric Research Center Fondazione R.E. Invernizzi and NOLIMITS Center, Università degli Studi di Milano, Milan, Italy
| | - Silvia Ferro
- Department of Comparative Biomedicine and Food Sciences, University of Padova, viale dell'Università 16, 35020, Legnaro, Padua, Italy
| | - Eric Zini
- AniCura Istituto Veterinario Novara, Strada Provinciale 9, 28060, Granozzo con Monticello, Novara, Italy
- Department of Animal Medicine, Production and Health, University of Padua, viale dell'Università 16, 35020, Legnaro, Padua, Italy
- Clinic for Small Animal Internal Medicine, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, 8057, Zurich, Switzerland
| | - Stefano Ricagno
- Institute of Molecular and Translational Cardiology, IRCCS Policlinico San Donato, 20097, Milan, Italy.
- Department of Biosciences, Università degli Studi di Milano, Milan, Italy.
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9
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He P, Liu B, Gao X, Yan Q, Pei R, Sun J, Chen Q, Hou R, Li Z, Zhang Y, Zhao J, Sun H, Feng B, Wang Q, Yi H, Hu P, Li P, Zhang Y, Chen Z, Niu X, Zhong X, Jin L, Liu X, Qu K, Ciazynska KA, Carter AP, Briggs JAG, Chen J, Liu J, Chen X, He J, Chen L, Xiong X. SARS-CoV-2 Delta and Omicron variants evade population antibody response by mutations in a single spike epitope. Nat Microbiol 2022; 7:1635-1649. [PMID: 36151403 PMCID: PMC9519457 DOI: 10.1038/s41564-022-01235-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 08/12/2022] [Indexed: 12/18/2022]
Abstract
Population antibody response is thought to be important in selection of virus variants. We report that SARS-CoV-2 infection elicits a population immune response that is mediated by a lineage of VH1-69 germline antibodies. A representative antibody R1-32 from this lineage was isolated. By cryo-EM, we show that it targets a semi-cryptic epitope in the spike receptor-binding domain. Binding to this non-ACE2 competing epitope results in spike destruction, thereby inhibiting virus entry. On the basis of epitope location, neutralization mechanism and analysis of antibody binding to spike variants, we propose that recurrent substitutions at 452 and 490 are associated with immune evasion of the identified population antibody response. These substitutions, including L452R (present in the Delta variant), disrupt interactions mediated by the VH1-69-specific hydrophobic HCDR2 to impair antibody-antigen association, enabling variants to escape. The first Omicron variants were sensitive to antibody R1-32 but subvariants that harbour L452R quickly emerged and spread. Our results provide insights into how SARS-CoV-2 variants emerge and evade host immune responses.
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Affiliation(s)
- Ping He
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Science, Beijing, China
| | - Banghui Liu
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Xijie Gao
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health - Guangdong Laboratory), Guangzhou, China
| | - Qihong Yan
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
- State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Rongjuan Pei
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China
| | - Jing Sun
- State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Qiuluan Chen
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health - Guangdong Laboratory), Guangzhou, China
| | - Ruitian Hou
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Science, Beijing, China
- Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, China
| | - Zimu Li
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Yanjun Zhang
- State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Jincun Zhao
- State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Hao Sun
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China
| | - Bo Feng
- School of Biomedical Sciences, Huaqiao University, Quanzhou, China
| | - Qian Wang
- State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Haisu Yi
- State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Peiyu Hu
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Pingchao Li
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Yudi Zhang
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Science, Beijing, China
| | - Zhilong Chen
- School of Biomedical Sciences, Huaqiao University, Quanzhou, China
- Xiamen United Institute of Respiratory Health, Xiamen, China
| | - Xuefeng Niu
- State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Xiaolin Zhong
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health - Guangdong Laboratory), Guangzhou, China
| | - Liang Jin
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health - Guangdong Laboratory), Guangzhou, China
| | | | - Kun Qu
- Infectious Diseases Translational Research Programme, Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Katarzyna A Ciazynska
- Structural Studies Division, Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Andrew P Carter
- Structural Studies Division, Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - John A G Briggs
- Structural Studies Division, Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
- Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Jizheng Chen
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
- Guangzhou Laboratory, Guangzhou International Bio Island, Guangzhou, Guangdong Province, China
| | - Jinsong Liu
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Xinwen Chen
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China.
- State Key Laboratory of Virology, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China.
- Guangzhou Laboratory, Guangzhou International Bio Island, Guangzhou, Guangdong Province, China.
| | - Jun He
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China.
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health - Guangdong Laboratory), Guangzhou, China.
| | - Ling Chen
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China.
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health - Guangdong Laboratory), Guangzhou, China.
- Guangzhou Eighth People's Hospital, Guangzhou Medical University, Guangzhou, China.
- Guangzhou Laboratory, Guangzhou International Bio Island, Guangzhou, Guangdong Province, China.
| | - Xiaoli Xiong
- State Key Laboratory of Respiratory Disease, CAS Key Laboratory of Regenerative Biology, Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China.
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health - Guangdong Laboratory), Guangzhou, China.
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10
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Agnihotri P, Shakya AK, Mishra AK, Pratap JV. Crystal structure and characterization of nucleoside diphosphate kinase from Vibrio cholerae. Biochimie 2021; 190:57-69. [PMID: 34242727 DOI: 10.1016/j.biochi.2021.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 06/30/2021] [Accepted: 07/04/2021] [Indexed: 11/26/2022]
Abstract
Nucleoside diphosphate kinases (NDK) are ubiquitous enzymes that catalyse the transfer of the γ phosphate from nucleoside triphosphates (NTPs) to nucleoside diphosphate (NDPs), to maintain appropriate NTP levels in cells. NDKs are associated with signal transduction, cell development, proliferation, differentiation, tumor metastasis, apoptosis and motility. The critical role of NDK in bacterial virulence renders it a potential drug target. The present manuscript reports crystal structure and functional characterization of Vibrio cholerae NDK (VNDK). The 16 kDa VNDK was crystallized in a solution containing 30% PEG 4000, 100 mM Tris-HCl pH 8.5 and 200 mM sodium acetate in orthorhombic space group P212121 with unit cell parameters a = 48.37, b = 71.21, c = 89.14 Å, α = β = γ = 90° with 2 molecules in asymmetric unit. The crystal structure was solved by molecular replacement and refined to crystallographic Rfactor and Rfree values of 22.8% and 25.8% respectively. VNDK exists as both dimer and tetramer in solution as confirmed by size exclusion chromatography, glutaraldehyde crosslinking and small angle X-ray scattering while the crystal structure appears to be a dimer. The biophysical characterization states that VNDK has kinase and DNase activity with maximum stability at pH 8-9 and temperature up to 40 °C. VNDK shows elevated thermolability as compared to other NDK and shows preferential binding with GTP rationalized using computational studies.
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Affiliation(s)
- Pragati Agnihotri
- Molecular and Structural Biology Division, CSIR-Central Drug Research Institute, B.S. 10/1, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow, 226031, U.P., India
| | - Anil Kumar Shakya
- Molecular and Structural Biology Division, CSIR-Central Drug Research Institute, B.S. 10/1, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow, 226031, U.P., India
| | - Arjun K Mishra
- Molecular and Structural Biology Division, CSIR-Central Drug Research Institute, B.S. 10/1, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow, 226031, U.P., India
| | - J Venkatesh Pratap
- Molecular and Structural Biology Division, CSIR-Central Drug Research Institute, B.S. 10/1, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow, 226031, U.P., India.
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11
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Sui L, Guo HC. ERAP1 binds peptide C-termini of different sequences and/or lengths by a common recognition mechanism. Immunobiology 2021; 226:152112. [PMID: 34247019 DOI: 10.1016/j.imbio.2021.152112] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 05/24/2021] [Accepted: 06/03/2021] [Indexed: 01/25/2023]
Abstract
Endoplasmic reticulum aminopeptidase 1 (ERAP1) plays a key role in controlling the immunopeptidomes available for presentation by MHC (major histocompatibility complex) molecules, thus influences immunodominance and cell-mediated immunity. It carries out this critical function by a unique molecular ruler mechanism that trims antigenic precursors in a peptide-length and sequence dependent manner. Acting as a molecular ruler, ERAP1 is capable of concurrently binding antigen peptide N- and C-termini by its N-terminal catalytic and C-terminal regulatory domains, respectively. As such ERAP1 can not only monitor substrate's lengths, but also exhibit a degree of sequence specificity at substrates' N- and C-termini. On the other hand, it also allows certain sequence and length flexibility in the middle part of peptide substrates that is critical for shaping MHC restricted immunopeptidomes. Here we report structural and biochemical studies to understand the molecular details on how ERAP1 can accommodate side chains of different anchoring residues at the substrate's C-terminus. We also examine how ERAP1 can accommodate antigen peptide precursors with length flexibility. Based on two newly determined complex structures, we find that ERAP1 binds the C-termini of peptides similarly even with different substrate sequences and/or lengths, by utilizing the same hydrophobic specificity pocket to accommodate peptides with either a Phe or Leu as the C-terminal anchor residue. In addition, SPR (surface plasmon resonance) binding analyses in solution further confirm the biological significance of these peptide-ERAP1 interactions. Similar to the binding mode of MHC-I molecules, ERAP1 accommodates for antigenic peptide length difference by allowing the peptide middle part to kink or bulge at the middle of its substrate binding cleft. This explains how SNP coded variants located at the middle of ERAP1 substrate binding cleft would influence the antigen pool and an individual's susceptibility to diseases.
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Affiliation(s)
- Lufei Sui
- Department of Biological Sciences, University of Massachusetts Lowell, 1 University Avenue, Lowell, MA 01854, USA
| | - Hwai-Chen Guo
- Department of Biological Sciences, University of Massachusetts Lowell, 1 University Avenue, Lowell, MA 01854, USA.
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12
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Salinas-Garcia MC, Plaza-Garrido M, Camara-Artigas A. The impact of oncogenic mutations of the viral Src kinase on the structure and stability of the SH3 domain. Acta Crystallogr D Struct Biol 2021; 77:854-866. [PMID: 34076598 PMCID: PMC8171063 DOI: 10.1107/s2059798321004344] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 04/22/2021] [Indexed: 03/26/2023] Open
Abstract
Src kinase belongs to the family of Src-related nonreceptor tyrosine kinases. Because of its physiological role in cell growth and proliferation, its activity is strictly controlled by several mechanisms. Nevertheless, in viral Src kinase (v-Src) some of these mechanisms fail, and its uncontrolled activity is responsible for the occurrence of cancer. Here, the crystal structures of three SH3-domain mutants of v-Src were determined to unveil the effects of these oncogenic mutations in this regulatory domain. Mutations in the n-Src and distal loops have a low impact on the overall structure of the domain and its capacity to form intertwined dimers. However, mutations in the RT loop compromise the stability of the domain and make the protein very prone to aggregation. Additionally, these mutations prevent the formation of intertwined dimers. The results show a synergistic effect between mutations in the RT loop and those in the n-Src and distal loops. Analysis of the structures of the v-Src SH3-domain mutants and the closed inactive conformation of cellular Src kinase (c-Src) point to a loss of the interactions that are required to establish the compact inactive form of the kinase. Nevertheless, an analysis of structures of the c-Src SH3 domain complexed with class I and II peptides points to minor changes in the interactions between the v-Src SH3 domain and these peptides. In this way, the structures reported here indicate that mutations in the RT loop might impair the kinase regulation mechanism without affecting the recognition of short proline-rich motifs in the target proteins of the kinase, thus explaining the oncogenic behaviour of the protein.
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Affiliation(s)
- M. Carmen Salinas-Garcia
- Department of Chemistry and Physics, Agrifood Campus of International Excellence (ceiA3) and CIAMBITAL, University of Almeria, Carretera de Sacramento s/n, 04120 Almeria, Spain
| | - Marina Plaza-Garrido
- Department of Chemistry and Physics, Agrifood Campus of International Excellence (ceiA3) and CIAMBITAL, University of Almeria, Carretera de Sacramento s/n, 04120 Almeria, Spain
| | - Ana Camara-Artigas
- Department of Chemistry and Physics, Agrifood Campus of International Excellence (ceiA3) and CIAMBITAL, University of Almeria, Carretera de Sacramento s/n, 04120 Almeria, Spain
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13
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Barnawi H, Woodward L, Fava N, Roubakha M, Shaw SD, Kubinec C, Naismith JH, Creuzenet C. Structure-function studies of the C3/C5 epimerases and C4 reductases of the Campylobacter jejuni capsular heptose modification pathways. J Biol Chem 2021; 296:100352. [PMID: 33524389 PMCID: PMC7949155 DOI: 10.1016/j.jbc.2021.100352] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 01/26/2021] [Accepted: 01/27/2021] [Indexed: 01/14/2023] Open
Abstract
Many bacteria produce polysaccharide-based capsules that protect them from environmental insults and play a role in virulence, host invasion, and other functions. Understanding how the polysaccharide components are synthesized could provide new means to combat bacterial infections. We have previously characterized two pairs of homologous enzymes involved in the biosynthesis of capsular sugar precursors GDP-6-deoxy-D-altro-heptose and GDP-6-OMe-L-gluco-heptose in Campylobacter jejuni. However, the substrate specificity and mechanism of action of these enzymes-C3 and/or C5 epimerases DdahB and MlghB and C4 reductases DdahC and MlghC-are unknown. Here, we demonstrate that these enzymes are highly specific for heptose substrates, using mannose substrates inefficiently with the exception of MlghB. We show that DdahB and MlghB feature a jellyroll fold typical of cupins, which possess a range of activities including epimerizations, GDP occupying a similar position as in cupins. DdahC and MlghC contain a Rossman fold, a catalytic triad, and a small C-terminal domain typical of short-chain dehydratase reductase enzymes. Integrating structural information with site-directed mutagenesis allowed us to identify features unique to each enzyme and provide mechanistic insight. In the epimerases, mutagenesis of H67, D173, N121, Y134, and Y132 suggested the presence of alternative catalytic residues. We showed that the reductases could reduce GDP-4-keto-6-deoxy-mannulose without prior epimerization although DdahC preferred the pre-epimerized substrate and identified T110 and H180 as important for substrate specificity and catalytic efficacy. This information can be exploited to identify inhibitors for therapeutic applications or to tailor these enzymes to synthesize novel sugars useful as glycobiology tools.
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Affiliation(s)
- Heba Barnawi
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
| | - Laura Woodward
- Biomedical Sciences Research Complex, St Andrews University, St Andrews, UK
| | - Natalie Fava
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
| | - Mikhail Roubakha
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
| | - Steve D Shaw
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
| | - Chelsea Kubinec
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada
| | - James H Naismith
- Biomedical Sciences Research Complex, St Andrews University, St Andrews, UK; Rosalind Franklin Institute, Research Complex at Harwell, Harwell Campus, Didcot, UK; Division of Structural Biology, Oxford University, Oxford, UK.
| | - Carole Creuzenet
- Department of Microbiology and Immunology, University of Western Ontario, London, Ontario, Canada.
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14
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Lokareddy RK, Ko YH, Hong N, Doll SG, Paduch M, Niederweis M, Kossiakoff AA, Cingolani G. Recognition of an α-helical hairpin in P22 large terminase by a synthetic antibody fragment. Acta Crystallogr D Struct Biol 2020; 76:876-888. [PMID: 32876063 PMCID: PMC7466751 DOI: 10.1107/s2059798320009912] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Accepted: 07/20/2020] [Indexed: 11/10/2022] Open
Abstract
The genome-packaging motor of tailed bacteriophages and herpesviruses is a multisubunit protein complex formed by several copies of a large (TerL) and a small (TerS) terminase subunit. The motor assembles transiently at the portal protein vertex of an empty precursor capsid to power the energy-dependent packaging of viral DNA. Both the ATPase and nuclease activities associated with genome packaging reside in TerL. Structural studies of TerL from bacteriophage P22 have been hindered by the conformational flexibility of this enzyme and its susceptibility to proteolysis. Here, an unbiased, synthetic phage-display Fab library was screened and a panel of high-affinity Fabs against P22 TerL were identified. This led to the discovery of a recombinant antibody fragment, Fab4, that binds a 33-amino-acid α-helical hairpin at the N-terminus of TerL with an equilibrium dissociation constant Kd of 71.5 nM. A 1.51 Å resolution crystal structure of Fab4 bound to the TerL epitope (TLE) together with a 1.15 Å resolution crystal structure of the unliganded Fab4, which is the highest resolution ever achieved for a Fab, elucidate the principles governing the recognition of this novel helical epitope. TLE adopts two different conformations in the asymmetric unit and buries as much as 1250 Å2 of solvent-accessible surface in Fab4. TLE recognition is primarily mediated by conformational changes in the third complementarity-determining region of the Fab4 heavy chain (CDR H3) that take place upon epitope binding. It is demonstrated that TLE can be introduced genetically at the N-terminus of a target protein, where it retains high-affinity binding to Fab4.
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Affiliation(s)
- Ravi K. Lokareddy
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, 1020 Locust Street, JAH-4E, Philadelphia, PA 19107, USA
| | - Ying-Hui Ko
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, 1020 Locust Street, JAH-4E, Philadelphia, PA 19107, USA
| | - Nathaniel Hong
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, 1020 Locust Street, JAH-4E, Philadelphia, PA 19107, USA
| | - Steven G. Doll
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, 1020 Locust Street, JAH-4E, Philadelphia, PA 19107, USA
| | - Marcin Paduch
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637, USA
| | - Michael Niederweis
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Anthony A. Kossiakoff
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637, USA
- Institute for Biophysical Dynamics, University of Chicago, Chicago, IL 60637, USA
| | - Gino Cingolani
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, 1020 Locust Street, JAH-4E, Philadelphia, PA 19107, USA
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15
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Norris A, Busch F, Schupfner M, Sterner R, Wysocki VH. Quaternary Structure of the Tryptophan Synthase α-Subunit Homolog BX1 from Zea mays. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:227-233. [PMID: 31933363 PMCID: PMC7313238 DOI: 10.1021/jasms.9b00068] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
BX1 from Zea mays (zmBX1) is an enzyme of plant secondary metabolism that generates indole for the synthesis of plant defensins. It is a homologue of the tryptophan synthase α-subunit, TrpA. Whereas TrpA itself is a monomer in solution, zmBX1 is dimeric, confirmed in our work by native MS. Using cross-linking and mutagenesis, we identified the physiological dimerization interface of zmBX1. We found that homodimerization has only minor effects on catalysis and stability. A comparison of the zmBX1-zmBX1 homodimer and zmTrpA-zmTrpB heterodimer interfaces suggest that homodimerization in zmBX1 might, at an early point in evolution, have served as a mechanism to exclude the interaction with the tryptophan synthase β-subunit (zmTrpB), marking its transition from primary to secondary metabolism.
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Affiliation(s)
- Andrew Norris
- The Ohio State University , Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology , Columbus , Ohio 43210 , United States
| | - Florian Busch
- The Ohio State University , Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology , Columbus , Ohio 43210 , United States
| | - Michael Schupfner
- University of Regensburg , Institute for Biophysics and Physical Biochemistry , Regensburg D-93053 , Germany
| | - Reinhard Sterner
- University of Regensburg , Institute for Biophysics and Physical Biochemistry , Regensburg D-93053 , Germany
| | - Vicki H Wysocki
- The Ohio State University , Department of Chemistry and Biochemistry and Resource for Native Mass Spectrometry Guided Structural Biology , Columbus , Ohio 43210 , United States
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16
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Crystal Structure of a GH3 β-Glucosidase from the Thermophilic Fungus Chaetomium thermophilum. Int J Mol Sci 2019; 20:ijms20235962. [PMID: 31783503 PMCID: PMC6929035 DOI: 10.3390/ijms20235962] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 11/20/2019] [Accepted: 11/25/2019] [Indexed: 11/17/2022] Open
Abstract
Beta-glucosidases (β-glucosidases) have attracted considerable attention in recent years for use in various biotechnological applications. They are also essential enzymes for lignocellulose degradation in biofuel production. However, cost-effective biomass conversion requires the use of highly efficient enzymes. Thus, the search for new enzymes as better alternatives of the currently available enzyme preparations is highly important. Thermophilic fungi are nowadays considered as a promising source of enzymes with improved stability. Here, the crystal structure of a family GH3 β-glucosidase from the thermophilic fungus Chaetomium thermophilum (CtBGL) was determined at a resolution of 2.99 Å. The structure showed the three-domain architecture found in other β-glucosidases with variations in loops and linker regions. The active site catalytic residues in CtBGL were identified as Asp287 (nucleophile) and Glu517 (acid/base). Structural comparison of CtBGL with Protein Data Bank (PDB)-deposited structures revealed variations among glycosylated Asn residues. The enzyme displayed moderate glycosylation compared to other GH3 family β-glucosidases with similar structure. A new glycosylation site at position Asn504 was identified in CtBGL. Moreover, comparison with respect to several thermostability parameters suggested that glycosylation and charged residues involved in electrostatic interactions may contribute to the stability of the enzyme at elevated temperatures. The reported CtBGL structure provides additional insights into the family GH3 enzymes and could offer new ideas for further improvements in β-glucosidases for more efficient use in biotechnological applications regarding cellulose degradation.
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17
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Salinas-Garcia MC, Plaza-Garrido M, Alba-Elena D, Camara-Artigas A. Major conformational changes in the structure of lysozyme obtained from a crystal with a very low solvent content. Acta Crystallogr F Struct Biol Commun 2019; 75:687-696. [PMID: 31702582 PMCID: PMC6839823 DOI: 10.1107/s2053230x19013189] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 09/25/2019] [Indexed: 11/10/2022] Open
Abstract
A new crystal form of lysozyme with a very low solvent content (26.35%) has been obtained in the orthorhombic space group P212121 (with unit-cell parameters a = 30.04, b = 51.68, c = 61.53 Å). The lysozyme structure obtained from these crystals does not show the typical overall fold. Instead, major conformational changes take place in some elements of the secondary structure and in the hydrophobic core of the protein. At the end of the central α-helix (α2), Glu35 is usually buried in the catalytic site and shows an abnormally high pKa value, which is key to the activity of the enzyme. The high pKa value of this glutamate residue is favoured by the hydrophobic environment, particularly by its neighbour Trp108, which is important for structural stability and saccharide binding. In this new structure, Trp108 shows a 90° rotation of its side chain, which results in the rearrangement of the hydrophobic core. Conformational changes also result in the exposure of Glu35 to the solvent, which impairs the catalytic site by increasing the distance between Glu35 and Asp52 and lowering the pKa value of the glutamate. Altogether, this new lysozyme structure reveals major conformational changes in the hydrophobic core and catalytic site that might play a role in the folding and bactericidal function of the protein.
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Affiliation(s)
- M. Carmen Salinas-Garcia
- Department of Chemistry and Physics, Agrifood Campus of International Excellence (ceiA3) and CIAMBITAL, University of Almería, Carretera de Sacramento s/n, 04120 Almería, Spain
| | - Marina Plaza-Garrido
- Department of Chemistry and Physics, Agrifood Campus of International Excellence (ceiA3) and CIAMBITAL, University of Almería, Carretera de Sacramento s/n, 04120 Almería, Spain
| | - Daniel Alba-Elena
- Department of Chemistry and Physics, Agrifood Campus of International Excellence (ceiA3) and CIAMBITAL, University of Almería, Carretera de Sacramento s/n, 04120 Almería, Spain
| | - Ana Camara-Artigas
- Department of Chemistry and Physics, Agrifood Campus of International Excellence (ceiA3) and CIAMBITAL, University of Almería, Carretera de Sacramento s/n, 04120 Almería, Spain
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18
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Camara-Artigas A, Murciano-Calles J, Martínez JC. Conformational changes in the third PDZ domain of the neuronal postsynaptic density protein 95. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2019; 75:381-391. [DOI: 10.1107/s2059798319001980] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 02/04/2019] [Indexed: 12/19/2022]
Abstract
PDZ domains are protein–protein recognition modules that interact with other proteins through short sequences at the carboxyl terminus. These domains are structurally characterized by a conserved fold composed of six β-strands and two α-helices. The third PDZ domain of the neuronal postsynaptic density protein 95 has an additional α-helix (α3), the role of which is not well known. In previous structures, a succinimide was identified in the β2–β3 loop instead of Asp332. The presence of this modified residue results in conformational changes in α3. In this work, crystallographic structures of the following have been solved: a truncated form of the third PDZ domain of the neuronal postsynaptic density protein 95 from which α3 has been removed, D332P and D332G variants of the protein, and a new crystal form of this domain showing the binding of Asp332 to the carboxylate-binding site of a symmetry-related molecule. Crystals of the wild type and variants were obtained in different space groups, which reflects the conformational plasticity of the domain. Indeed, the overall analysis of these structures suggests that the conformation of the β2–β3 loop is correlated with the fold acquired by α3. The alternate conformation of the β2–β3 loop affects the electrostatics of the carboxylate-binding site and might modulate the binding of different PDZ-binding motifs.
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19
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Furukawa N, Miyanaga A, Nakajima M, Taguchi H. Structural Basis of Sequential Allosteric Transitions in Tetrameric d-Lactate Dehydrogenases from Three Gram-Negative Bacteria. Biochemistry 2018; 57:5388-5406. [PMID: 30149697 DOI: 10.1021/acs.biochem.8b00557] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
d-Lactate dehydrogenases (d-LDHs) from Fusobacterium nucleatum (FnLDH) and Escherichia coli (EcLDH) exhibit positive cooperativity in substrate binding, and the Pseudomonas aeruginosa enzyme (PaLDH) shows negatively cooperative substrate binding. The apo and ternary complex structures of FnLDH and PaLDH have been determined together with the apo-EcLDH structure. The three enzymes consistently form homotetrameric structures with three symmetric axes, the P-, Q-, and R-axes, unlike Lactobacillus d-LDHs, P-axis-related dimeric enzymes, although apo-FnLDH and EcLDH form asymmetric and distorted quaternary structures. The tetrameric structure allows apo-FnLDH and EcLDH to form wide intersubunit contact surfaces between the opened catalytic domains of the two Q-axis-related subunits in coordination with their asymmetric and distorted quaternary structures. These contact surfaces comprise intersubunit hydrogen bonds and hydrophobic interactions and likely prevent the domain closure motion during initial substrate binding. In contrast, apo-PaLDH possesses a highly symmetrical quaternary structure and partially closed catalytic domains that are favorable for initial substrate binding and forms virtually no intersubunit contact surface between the catalytic domains, which present their negatively charged surfaces to each other at the subunit interface. Complex FnLDH and PaLDH possess highly symmetrical quaternary structures with closed forms of the catalytic domains, which are separate from each other at the subunit interface. Structure-based mutations successfully converted the three enzymes to their dimeric forms, which exhibited no significant cooperativity in substrate binding. These observations indicate that the three enzymes undergo typical sequential allosteric transitions to exhibit their distinctive allosteric functions through the tetrameric structures.
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Affiliation(s)
- Nayuta Furukawa
- Department of Applied Biological Science, Faculty of Science and Technology , Tokyo University of Science , 2641 Yamazaki , Noda , Chiba 278-8510 , Japan.,Department of Applied Life Sciences , Niigata University of Pharmacy and Applied Life Sciences , 265-1 Higashijima , Akiha-ku, Niigata 956-8603 , Japan
| | - Akimasa Miyanaga
- Department of Chemistry , Tokyo Institute of Technology , 2-12-1 O-okayama , Meguro-ku, Tokyo 152-8551 , Japan
| | - Masahiro Nakajima
- Department of Applied Biological Science, Faculty of Science and Technology , Tokyo University of Science , 2641 Yamazaki , Noda , Chiba 278-8510 , Japan
| | - Hayao Taguchi
- Department of Applied Biological Science, Faculty of Science and Technology , Tokyo University of Science , 2641 Yamazaki , Noda , Chiba 278-8510 , Japan
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20
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Investigation of protein quaternary structure via stoichiometry and symmetry information. PLoS One 2018; 13:e0197176. [PMID: 29864163 PMCID: PMC5986128 DOI: 10.1371/journal.pone.0197176] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 04/27/2018] [Indexed: 11/30/2022] Open
Abstract
The Protein Data Bank (PDB) is the single worldwide archive of experimentally-determined three-dimensional (3D) structures of proteins and nucleic acids. As of January 2017, the PDB housed more than 125,000 structures and was growing by more than 11,000 structures annually. Since the 3D structure of a protein is vital to understand the mechanisms of biological processes, diseases, and drug design, correct oligomeric assembly information is of critical importance. Unfortunately, the biologically relevant oligomeric form of a 3D structure is not directly obtainable by X-ray crystallography, whilst in solution methods (NMR or single particle EM) it is known from the experiment. Instead, this information may be provided by the PDB Depositor as metadata coming from additional experiments, be inferred by sequence-sequence comparisons with similar proteins of known oligomeric state, or predicted using software, such as PISA (Proteins, Interfaces, Structures and Assemblies) or EPPIC (Evolutionary Protein Protein Interface Classifier). Despite significant efforts by professional PDB Biocurators during data deposition, there remain a number of structures in the archive with incorrect quaternary structure descriptions (or annotations). Further investigation is, therefore, needed to evaluate the correctness of quaternary structure annotations. In this study, we aim to identify the most probable oligomeric states for proteins represented in the PDB. Our approach evaluated the performance of four independent prediction methods, including text mining of primary publications, inference from homologous protein structures, and two computational methods (PISA and EPPIC). Aggregating predictions to give consensus results outperformed all four of the independent prediction methods, yielding 83% correct, 9% wrong, and 8% inconclusive predictions, when tested with a well-curated benchmark dataset. We have developed a freely-available web-based tool to make this approach accessible to researchers and PDB Biocurators (http://quatstruct.rcsb.org/).
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21
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Plaza-Garrido M, Salinas-Garcia MC, Camara-Artigas A. Orthorhombic lysozyme crystallization at acidic pH values driven by phosphate binding. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2018; 74:480-489. [PMID: 29717719 DOI: 10.1107/s205979831800517x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 04/02/2018] [Indexed: 11/10/2022]
Abstract
The structure of orthorhombic lysozyme has been obtained at 298 K and pH 4.5 using sodium chloride as the precipitant and in the presence of sodium phosphate at a concentration as low as 5 mM. Crystals belonging to space group P212121 (unit-cell parameters a = 30, b = 56, c = 73 Å, α = β = γ = 90.00°) diffracted to a resolution higher than 1 Å, and the high quality of these crystals permitted the identification of a phosphate ion bound to Arg14 and His15. The binding of this ion produces long-range conformational changes affecting the loop containing Ser60-Asn74. The negatively charged phosphate ion shields the electrostatic repulsion of the positively charged arginine and histidine residues, resulting in higher stability of the phosphate-bound lysozyme. Additionally, a low-humidity orthorhombic variant was obtained at pH 4.5, and comparison with those previously obtained at pH 6.5 and 9.5 shows a 1.5 Å displacement of the fifth α-helix towards the active-site cavity, which might be relevant to protein function. Since lysozyme is broadly used as a model protein in studies related to protein crystallization and amyloid formation, these results indicate that the interaction of some anions must be considered when analysing experiments performed at acidic pH values.
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Affiliation(s)
- Marina Plaza-Garrido
- Department of Chemistry and Physics, Agrifood Campus of International Excellence (ceiA3) and CIAMBITAL, University of Almería, Carretera de Sacramento, 04120 Almeria, Spain
| | - M Carmen Salinas-Garcia
- Department of Chemistry and Physics, Agrifood Campus of International Excellence (ceiA3) and CIAMBITAL, University of Almería, Carretera de Sacramento, 04120 Almeria, Spain
| | - Ana Camara-Artigas
- Department of Chemistry and Physics, Agrifood Campus of International Excellence (ceiA3) and CIAMBITAL, University of Almería, Carretera de Sacramento, 04120 Almeria, Spain
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22
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Hadi-Alijanvand H, Rouhani M. Partner-Specific Prediction of Protein-Dimer Stability from Unbound Structure of Monomer. J Chem Inf Model 2018; 58:733-745. [PMID: 29444397 DOI: 10.1021/acs.jcim.7b00606] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Protein complexes play deterministic roles in live entities in sensing, compiling, controlling, and responding to external and internal stimuli. Thermodynamic stability is an important property of protein complexes; having knowledge about complex stability helps us to understand the basics of protein assembly-related diseases and the mechanism of protein assembly clearly. Enormous protein-protein interactions, detected by high-throughput methods, necessitate finding fast methods for predicting the stability of protein assemblies in a quantitative and qualitative manner. The existing methods of predicting complex stability need knowledge about the three-dimensional (3D) structure of the intended protein complex. Here, we introduce a new method for predicting dissociation free energy of subunits by analyzing the structural and topological properties of a protein binding patch on a single subunit of the desired protein complex. The method needs the 3D structure of just one subunit and the information about the position of the intended binding site on the surface of that subunit to predict dimer stability in a classwise manner. The patterns of structural and topological properties of a protein binding patch are decoded by recurrence quantification analysis. Nonparametric discrimination is then utilized to predict the stability class of the intended dimer with accuracy greater than 85%.
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Affiliation(s)
- Hamid Hadi-Alijanvand
- Department of Biological Sciences , Institute for Advanced Studies in Basic Sciences (IASBS) , Zanjan , 45137-66731 , Iran
| | - Maryam Rouhani
- Department of Biological Sciences , Institute for Advanced Studies in Basic Sciences (IASBS) , Zanjan , 45137-66731 , Iran
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23
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Confirmation of intersubunit connectivity and topology of designed protein complexes by native MS. Proc Natl Acad Sci U S A 2018; 115:1268-1273. [PMID: 29351988 DOI: 10.1073/pnas.1713646115] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Computational protein design provides the tools to expand the diversity of protein complexes beyond those found in nature. Understanding the rules that drive proteins to interact with each other enables the design of protein-protein interactions to generate specific protein assemblies. In this work, we designed protein-protein interfaces between dimers and trimers to generate dodecameric protein assemblies with dihedral point group symmetry. We subsequently analyzed the designed protein complexes by native MS. We show that the use of ion mobility MS in combination with surface-induced dissociation (SID) allows for the rapid determination of the stoichiometry and topology of designed complexes. The information collected along with the speed of data acquisition and processing make SID ion mobility MS well-suited to determine key structural features of designed protein complexes, thereby circumventing the requirement for more time- and sample-consuming structural biology approaches.
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24
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Bhoye D, Cherian SS. Computational analysis of the effect of polymerase acidic (PA) gene mutation F35L in the 2009 pandemic influenza A (H1N1) virus on binding aspects of mononucleotides in the endonuclease domain. Arch Virol 2017; 163:1031-1036. [PMID: 29273880 DOI: 10.1007/s00705-017-3681-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 12/05/2017] [Indexed: 11/26/2022]
Abstract
An F35L mutation in the N-terminal domain of the polymerase acidic protein (PA-Nter), which contains the active site of the endonuclease, has been reported to result in higher polymerase activity in mouse-adapted strains of the 2009 pandemic influenza A H1N1 virus. We modeled wild and mutant complexes of uridine 5'-monophosphate (UMP) as the endonuclease substrate and performed molecular dynamics simulations. The results demonstrated that the F35L mutation could result in a changed orientation of a helix containing active site residues and improve the ligand affinity in the mutant strain. This study suggests a molecular mechanism of enhanced polymerase activity.
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Affiliation(s)
- Dipali Bhoye
- Bioinformatics and Data Management Group, National Institute of Virology, 20-A, Dr. Ambedkar Road, Post Box No. 11, Pune, Maharashtra, 411001, India
| | - Sarah S Cherian
- Bioinformatics and Data Management Group, National Institute of Virology, 20-A, Dr. Ambedkar Road, Post Box No. 11, Pune, Maharashtra, 411001, India.
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25
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Peña-Soler E, Aranda J, López-Estepa M, Gómez S, Garces F, Coll M, Fernández FJ, Tuñon I, Vega MC. Insights into the inhibited form of the redox-sensitive SufE-like sulfur acceptor CsdE. PLoS One 2017; 12:e0186286. [PMID: 29045454 PMCID: PMC5646864 DOI: 10.1371/journal.pone.0186286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 09/28/2017] [Indexed: 11/18/2022] Open
Abstract
Sulfur trafficking in living organisms relies on transpersulfuration reactions consisting in the enzyme-catalyzed transfer of S atoms via activated persulfidic S across protein-protein interfaces. The recent elucidation of the mechanistic basis for transpersulfuration in the CsdA-CsdE model system has paved the way for a better understanding of its role under oxidative stress. Herein we present the crystal structure of the oxidized, inactivated CsdE dimer at 2.4 Å resolution. The structure sheds light into the activation of the Cys61 nucleophile on its way from a solvent-secluded position in free CsdE to a fully extended conformation in the persulfurated CsdA-CsdE complex. Molecular dynamics simulations of available CsdE structures allow to delineate the sequence of conformational changes underwent by CsdE and to pinpoint the key role played by the deprotonation of the Cys61 thiol. The low-energy subunit orientation in the disulfide-bridged CsdE dimer demonstrates the likely physiologic relevance of this oxidative dead-end form of CsdE, suggesting that CsdE could act as a redox sensor in vivo.
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Affiliation(s)
- Esther Peña-Soler
- Chemical and Physical Biology Department, Center for Biological Research (CIB-CSIC), Madrid, Spain
- Institut de Biologia Molecular de Barcelona (IBMB-CSIC), Barcelona, Spain
- Institute for Biomedical Research (IRB Barcelona), Barcelona, Spain
| | - Juan Aranda
- Departamento de Química Física, Universitat de València, Burjassot, Spain
| | - Miguel López-Estepa
- Chemical and Physical Biology Department, Center for Biological Research (CIB-CSIC), Madrid, Spain
| | - Sara Gómez
- Chemical and Physical Biology Department, Center for Biological Research (CIB-CSIC), Madrid, Spain
| | - Fernando Garces
- The Scripps Research Institute, La Jolla, California, United States of America
| | - Miquel Coll
- Institut de Biologia Molecular de Barcelona (IBMB-CSIC), Barcelona, Spain
- Institute for Biomedical Research (IRB Barcelona), Barcelona, Spain
| | - Francisco J. Fernández
- Chemical and Physical Biology Department, Center for Biological Research (CIB-CSIC), Madrid, Spain
- Abvance Biotech srl, Madrid, Spain
| | - Iñaki Tuñon
- Departamento de Química Física, Universitat de València, Burjassot, Spain
- * E-mail: , (MCV); (IT)
| | - M. Cristina Vega
- Chemical and Physical Biology Department, Center for Biological Research (CIB-CSIC), Madrid, Spain
- * E-mail: , (MCV); (IT)
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26
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Bohn JA, Thummar K, York A, Raymond A, Brown WC, Bieniasz PD, Hatziioannou T, Smith JL. APOBEC3H structure reveals an unusual mechanism of interaction with duplex RNA. Nat Commun 2017; 8:1021. [PMID: 29044109 PMCID: PMC5647330 DOI: 10.1038/s41467-017-01309-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 09/06/2017] [Indexed: 11/08/2022] Open
Abstract
The APOBEC3 family of cytidine deaminases cause lethal hypermutation of retroviruses via deamination of newly reverse-transcribed viral DNA. Their ability to bind RNA is essential for virion infiltration and antiviral activity, yet the mechanisms of viral RNA recognition are unknown. By screening naturally occurring, polymorphic, non-human primate APOBEC3H variants for biological and crystallization properties, we obtained a 2.24-Å crystal structure of pig-tailed macaque APOBEC3H with bound RNA. Here, we report that APOBEC3H forms a dimer around a short RNA duplex and, despite the bound RNA, has potent cytidine deaminase activity. The structure reveals an unusual RNA-binding mode in which two APOBEC3H molecules at opposite ends of a seven-base-pair duplex interact extensively with both RNA strands, but form no protein-protein contacts. CLIP-seq analysis revealed that APOBEC3H preferentially binds to sequences in the viral genome predicted to contain duplexes, a property that may facilitate both virion incorporation and catalytic activity.
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Affiliation(s)
- Jennifer A Bohn
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Keyur Thummar
- Laboratory of Retrovirology, The Rockefeller University, New York, NY, 10065, USA
- Howard Hughes Medical Institute, The Rockefeller University, New York, NY, 10065, USA
| | - Ashley York
- Laboratory of Retrovirology, The Rockefeller University, New York, NY, 10065, USA
- Howard Hughes Medical Institute, The Rockefeller University, New York, NY, 10065, USA
| | - Alice Raymond
- Laboratory of Retrovirology, The Rockefeller University, New York, NY, 10065, USA
- Howard Hughes Medical Institute, The Rockefeller University, New York, NY, 10065, USA
| | - W Clay Brown
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Paul D Bieniasz
- Laboratory of Retrovirology, The Rockefeller University, New York, NY, 10065, USA
- Howard Hughes Medical Institute, The Rockefeller University, New York, NY, 10065, USA
| | | | - Janet L Smith
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, 48109, USA.
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA.
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Unraveling the Self-Assembly of the Pseudomonas aeruginosa XcpQ Secretin Periplasmic Domain Provides New Molecular Insights into Type II Secretion System Secreton Architecture and Dynamics. mBio 2017; 8:mBio.01185-17. [PMID: 29042493 PMCID: PMC5646246 DOI: 10.1128/mbio.01185-17] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The type II secretion system (T2SS) releases large folded exoproteins across the envelope of many Gram-negative pathogens. This secretion process therefore requires specific gating, interacting, and dynamics properties mainly operated by a bipartite outer membrane channel called secretin. We have a good understanding of the structure-function relationship of the pore-forming C-terminal domain of secretins. In contrast, the high flexibility of their periplasmic N-terminal domain has been an obstacle in obtaining the detailed structural information required to uncover its molecular function. In Pseudomonas aeruginosa, the Xcp T2SS plays an important role in bacterial virulence by its capacity to deliver a large panel of toxins and degradative enzymes into the surrounding environment. Here, we revealed that the N-terminal domain of XcpQ secretin spontaneously self-assembled into a hexamer of dimers independently of its C-terminal domain. Furthermore, and by using multidisciplinary approaches, we elucidate the structural organization of the XcpQ N domain and demonstrate that secretin flexibility at interdimer interfaces is mandatory for its function. Bacterial secretins are large homooligomeric proteins constituting the outer membrane pore-forming element of several envelope-embedded nanomachines essential in bacterial survival and pathogenicity. They comprise a well-defined membrane-embedded C-terminal domain and a modular periplasmic N-terminal domain involved in substrate recruitment and connection with inner membrane components. We are studying the XcpQ secretin of the T2SS present in the pathogenic bacterium Pseudomonas aeruginosa. Our data highlight the ability of the XcpQ N-terminal domain to spontaneously oligomerize into a hexamer of dimers. Further in vivo experiments revealed that this domain adopts different conformations essential for the T2SS secretion process. These findings provide new insights into the functional understanding of bacterial T2SS secretins.
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Leite WC, Galvão CW, Saab SC, Iulek J, Etto RM, Steffens MBR, Chitteni-Pattu S, Stanage T, Keck JL, Cox MM. Structural and Functional Studies of H. seropedicae RecA Protein - Insights into the Polymerization of RecA Protein as Nucleoprotein Filament. PLoS One 2016; 11:e0159871. [PMID: 27447485 PMCID: PMC4957752 DOI: 10.1371/journal.pone.0159871] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 07/08/2016] [Indexed: 11/18/2022] Open
Abstract
The bacterial RecA protein plays a role in the complex system of DNA damage repair. Here, we report the functional and structural characterization of the Herbaspirillum seropedicae RecA protein (HsRecA). HsRecA protein is more efficient at displacing SSB protein from ssDNA than Escherichia coli RecA protein. HsRecA also promotes DNA strand exchange more efficiently. The three dimensional structure of HsRecA-ADP/ATP complex has been solved to 1.7 Å resolution. HsRecA protein contains a small N-terminal domain, a central core ATPase domain and a large C-terminal domain, that are similar to homologous bacterial RecA proteins. Comparative structural analysis showed that the N-terminal polymerization motif of archaeal and eukaryotic RecA family proteins are also present in bacterial RecAs. Reconstruction of electrostatic potential from the hexameric structure of HsRecA-ADP/ATP revealed a high positive charge along the inner side, where ssDNA is bound inside the filament. The properties of this surface may explain the greater capacity of HsRecA protein to bind ssDNA, forming a contiguous nucleoprotein filament, displace SSB and promote DNA exchange relative to EcRecA. Our functional and structural analyses provide insight into the molecular mechanisms of polymerization of bacterial RecA as a helical nucleoprotein filament.
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Affiliation(s)
- Wellington C. Leite
- Department of Physics, Ponta Grossa State University (UEPG), Av. Carlos Cavalcanti, 4748, CEP. 84.030–900, Ponta Grossa, PR, Brazil
- * E-mail: (MC); (WL)
| | - Carolina W. Galvão
- Department of Structural and Molecular Biology and Genetics, Ponta Grossa State University (UEPG), CEP 84030–900, Ponta Grossa, PR, Brazil
| | - Sérgio C. Saab
- Department of Physics, Ponta Grossa State University (UEPG), Av. Carlos Cavalcanti, 4748, CEP. 84.030–900, Ponta Grossa, PR, Brazil
| | - Jorge Iulek
- Department of Chemistry, Ponta Grossa State University (UEPG), CEP 84030–900, Ponta Grossa, PR, Brazil
| | - Rafael M. Etto
- Department of Chemistry, Ponta Grossa State University (UEPG), CEP 84030–900, Ponta Grossa, PR, Brazil
| | - Maria B. R. Steffens
- Department of Biochemistry and Molecular Biology, Federal University of Parana, CEP 81531–980 Curitiba, Brazil
| | - Sindhu Chitteni-Pattu
- Department of Biochemistry, University of Wisconsin–Madison, Madison, WI, 53706–1544, United States of America
| | - Tyler Stanage
- Department of Biochemistry, University of Wisconsin–Madison, Madison, WI, 53706–1544, United States of America
| | - James L. Keck
- Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53706, United States of America
| | - Michael M. Cox
- Department of Biochemistry, University of Wisconsin–Madison, Madison, WI, 53706–1544, United States of America
- * E-mail: (MC); (WL)
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Brandt AML, Batista PR, Souza-Silva F, Alves CR, Caffarena ER. Exploring the unbinding of Leishmania (L.) amazonensis CPB derived-epitopes from H2 MHC class I proteins. Proteins 2016; 84:473-87. [PMID: 26798994 DOI: 10.1002/prot.24994] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Revised: 01/07/2016] [Accepted: 01/08/2016] [Indexed: 11/07/2022]
Abstract
New strategies to control Leishmania disease demand an extensive knowledge about several aspects of infection including the understanding of its molecular events. In murine models, cysteine proteinase B from Leishmania amazonensis promotes regulation of immune response, and fragments from its C-terminus extension (cyspep) can play a decisive role in the host-parasite interaction. The interaction between cyspep-derived peptides and major histocompatibility complex (MHC) proteins is a crucial factor in Leishmania infections. Seven cyspep-derived peptides, previously identified as capable of interacting with H-2 (murine) MHC class I proteins, were studied in this work. We established a protocol to simulate the unbinding of these peptides from the cleft of H-2 receptors. From the simulations, we estimated the corresponding free energy of dissociation (ΔGd ) and described the molecular events that occur during the exit of peptides from the cleft. To test the reliability of this method, we first applied it to a calibration set of four crystallographic MHC/peptide complexes. Next, we explored the unbinding of the seven complexes mentioned above. Results were consistent with ΔGd values obtained from surface plasmon resonance (SPR) experiments. We also identified some of the primary interactions between peptides and H-2 receptors, and we detected three regions of influence for the interaction. This pattern was systematically observed for the peptides and helped determine a minimum distance for the real interaction between peptides and H-2 proteins occurring at ∼ 25 Å.
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Affiliation(s)
- Artur M L Brandt
- Programa De Computação Científica (PROCC), Fundação Oswaldo Cruz, Manguinhos, Rio De Janeiro, RJ, CEP 21040-360, Brazil.,Faculdade De Educação Tecnológica Do Estado Do Rio De Janeiro (FAETERJ), Rio De Janeiro, RJ, CEP 21311-280, Brazil
| | - Paulo Ricardo Batista
- Programa De Computação Científica (PROCC), Fundação Oswaldo Cruz, Manguinhos, Rio De Janeiro, RJ, CEP 21040-360, Brazil
| | - Franklin Souza-Silva
- Laboratório De Biologia Molecular E Doenças Endêmicas, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Manguinhos, Rio De Janeiro, RJ, CEP 21040-360, Brazil
| | - Carlos Roberto Alves
- Laboratório De Biologia Molecular E Doenças Endêmicas, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Manguinhos, Rio De Janeiro, RJ, CEP 21040-360, Brazil
| | - Ernesto Raul Caffarena
- Programa De Computação Científica (PROCC), Fundação Oswaldo Cruz, Manguinhos, Rio De Janeiro, RJ, CEP 21040-360, Brazil
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Camara-Artigas A, Plaza-Garrido M, Martinez-Rodriguez S, Bacarizo J. New crystal form of human ubiquitin in the presence of magnesium. Acta Crystallogr F Struct Biol Commun 2016; 72:29-35. [PMID: 26750481 PMCID: PMC4708047 DOI: 10.1107/s2053230x15023390] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 12/05/2015] [Indexed: 01/07/2023] Open
Abstract
Ubiquitin is a small globular protein that has a considerable number of lysine residues on its surface. This results in a high surface entropy that precludes the formation of crystal-packing interactions. To date, only a few structures of the native form of ubiquitin have been solved, and most of the crystals that led to these structures were obtained in the presence of different divalent metal cations. In this work, a new crystallographic structure of human ubiquitin solved from crystals grown in the presence of magnesium is presented. The crystals belonged to a triclinic space group, with unit-cell parameters a = 29.96, b = 30.18, c = 41.41 Å, α = 88.52, β = 79.12, γ = 67.37°. The crystal lattice is composed of stacked layers of human ubiquitin molecules with a large hydrophobic interface and a smaller polar interface in which the magnesium ion lies at the junction between adjacent layers in the crystal. The metal ion appears in a hexa-aquo coordination, which is key to facilitating the crystallization of the protein.
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Affiliation(s)
- Ana Camara-Artigas
- Department of Chemistry and Physics, University of Almeria, Agrifood Campus of International Excellence (ceiA3), Carretera de Sacramento (s/n), 04120 Almeria, Spain
| | - Marina Plaza-Garrido
- Department of Chemistry and Physics, University of Almeria, Agrifood Campus of International Excellence (ceiA3), Carretera de Sacramento (s/n), 04120 Almeria, Spain
| | - Sergio Martinez-Rodriguez
- Department of Physical Chemistry, University of Granada, Avdenida de Fuentenueva s/n, 18071 Granada, Spain
| | - Julio Bacarizo
- Department of Chemistry and Physics, University of Almeria, Agrifood Campus of International Excellence (ceiA3), Carretera de Sacramento (s/n), 04120 Almeria, Spain
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Capitani G, Duarte JM, Baskaran K, Bliven S, Somody JC. Understanding the fabric of protein crystals: computational classification of biological interfaces and crystal contacts. Bioinformatics 2015; 32:481-9. [PMID: 26508758 PMCID: PMC4743631 DOI: 10.1093/bioinformatics/btv622] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 10/16/2015] [Indexed: 11/20/2022] Open
Abstract
Modern structural biology still draws the vast majority of information from crystallography, a technique where the objects being investigated are embedded in a crystal lattice. Given the complexity and variety of those objects, it becomes fundamental to computationally assess which of the interfaces in the lattice are biologically relevant and which are simply crystal contacts. Since the mid-1990s, several approaches have been applied to obtain high-accuracy classification of crystal contacts and biological protein–protein interfaces. This review provides an overview of the concepts and main approaches to protein interface classification: thermodynamic estimation of interface stability, evolutionary approaches based on conservation of interface residues, and co-occurrence of the interface across different crystal forms. Among the three categories, evolutionary approaches offer the strongest promise for improvement, thanks to the incessant growth in sequence knowledge. Importantly, protein interface classification algorithms can also be used on multimeric structures obtained using other high-resolution techniques or for protein assembly design or validation purposes. A key issue linked to protein interface classification is the identification of the biological assembly of a crystal structure and the analysis of its symmetry. Here, we highlight the most important concepts and problems to be overcome in assembly prediction. Over the next few years, tools and concepts of interface classification will probably become more frequently used and integrated in several areas of structural biology and structural bioinformatics. Among the main challenges for the future are better addressing of weak interfaces and the application of interface classification concepts to prediction problems like protein–protein docking. Supplementary information: Supplementary data are available at Bioinformatics online. Contact:guido.capitani@psi.ch
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Affiliation(s)
- Guido Capitani
- Laboratory of Biomolecular Research, Paul Scherrer Institute, OFLC/110, 5232 Villigen PSI, Department of Biology, ETH Zurich, 8093 Zurich, Switzerland
| | - Jose M Duarte
- Laboratory of Biomolecular Research, Paul Scherrer Institute, OFLC/110, 5232 Villigen PSI, Department of Biology, ETH Zurich, 8093 Zurich, Switzerland
| | - Kumaran Baskaran
- Laboratory of Biomolecular Research, Paul Scherrer Institute, OFLC/110, 5232 Villigen PSI
| | - Spencer Bliven
- Laboratory of Biomolecular Research, Paul Scherrer Institute, OFLC/110, 5232 Villigen PSI, Bioinformatics and Systems Biology Program, UC San Diego, La Jolla, CA 92093, National Center for Biotechnology Information, NIH, Bethesda, MD 20894, USA and
| | - Joseph C Somody
- Laboratory of Biomolecular Research, Paul Scherrer Institute, OFLC/110, 5232 Villigen PSI, Department of Computer Science, ETH Zurich, 8092 Zurich, Switzerland
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32
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Healy EF. A model for non-obligate oligomer formation in protein aggregration. Biochem Biophys Res Commun 2015; 465:523-7. [PMID: 26282203 PMCID: PMC4564312 DOI: 10.1016/j.bbrc.2015.08.052] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 08/12/2015] [Indexed: 11/30/2022]
Abstract
Using solvent-exposed intramolecular backbone hydrogen bonds as physico-chemical descriptors for protein packing, a role for transient, non-obligate oligomers in the formation of aberrant protein aggregates is presented. Oligomeric models of the both wild type (wt) and select mutant variants of superoxide dismutase (SOD1) are proposed to provide a structural basis for investigating the etiology of Amyotrophic Lateral Sclerosis (ALS).
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Affiliation(s)
- Eamonn F Healy
- Department of Chemistry, St. Edward's University, Austin, TX 78704, USA.
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33
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Martinez-Rodriguez S, Bacarizo J, Luque I, Camara-Artigas A. Crystal structure of the first WW domain of human YAP2 isoform. J Struct Biol 2015; 191:381-7. [DOI: 10.1016/j.jsb.2015.08.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 08/06/2015] [Accepted: 08/06/2015] [Indexed: 11/16/2022]
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Handrkova H, Schroeder V, Kohler HP. The activation peptide of coagulation factor XIII is vital for its expression and stability. J Thromb Haemost 2015; 13:1449-58. [PMID: 26083359 DOI: 10.1111/jth.13035] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Accepted: 05/31/2015] [Indexed: 01/31/2023]
Abstract
BACKGROUND The human activation peptide of factor XIII (AP-FXIII) comprises the first 37 amino acids of the N-terminus and holds the FXIII in an inactive state. FXIII is activated either proteolytically by cleavage of AP-FXIII by thrombin, or non-proteolytically by high calcium concentrations. OBJECTIVE To investigate the role of AP-FXIII in the expression and stability of FXIII. METHODS We cloned 13 FXIII variants with progressive truncations of AP-FXIII from the N-terminus (delN-FXIII-A), expressed them in mammalian cells, and measured their thermostability, activation, and transglutaminase activity. We also used in silico calculations to analyze the stability of hypothetical delN-FXIII dimers and to identify crucial motifs within AP-FXIII. RESULTS Variants with deletions longer than the first 10 amino acids and an R11Q point mutant were not expressed as proteins. In silico calculations indicated that the sequence (8) FGGR(12) R plays a substantial role in intersubunit interactions in FXIII-A2 homodimers. In agreement with this prediction, the temperature stability of delN-FXIII variants decreased with increasing length of deletion. These results may suggest a role of the N-terminus of AP-FXIII in dimer stability. Substantial sequence homology was found among activation peptides of vertebrate and even invertebrate (crustacean) FXIII-A orthologs, which further supports our conclusion. CONCLUSIONS We conclude that deletion of 11 or more N-terminal amino acids disrupts intersubunit interactions, which may prevent FXIII-A2 homodimer formation. Therefore, AP-FXIII plays an important role in the stability of the FXIII-A2 dimer.
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Affiliation(s)
- H Handrkova
- Hemostasis Research Laboratory, University Clinic of Hematology, University Hospital of Bern, Bern, Switzerland
- Department of Clinical Research, University of Bern, Bern, Switzerland
| | - V Schroeder
- Hemostasis Research Laboratory, University Clinic of Hematology, University Hospital of Bern, Bern, Switzerland
- Department of Clinical Research, University of Bern, Bern, Switzerland
| | - H P Kohler
- Hemostasis Research Laboratory, University Clinic of Hematology, University Hospital of Bern, Bern, Switzerland
- Department of Clinical Research, University of Bern, Bern, Switzerland
- Department of Medicine, Spital Netz Bern Hospitals Tiefenau Ziegler, Bern, Switzerland
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Curry S. Structural Biology: A Century-long Journey into an Unseen World. INTERDISCIPLINARY SCIENCE REVIEWS : ISR 2015; 40:308-328. [PMID: 26740732 PMCID: PMC4697198 DOI: 10.1179/0308018815z.000000000120] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
When the first atomic structures of salt crystals were determined by the Braggs in 1912-1913, the analytical power of X-ray crystallography was immediately evident. Within a few decades the technique was being applied to the more complex molecules of chemistry and biology and is rightly regarded as the foundation stone of structural biology, a field that emerged in the 1950s when X-ray diffraction analysis revealed the atomic architecture of DNA and protein molecules. Since then the toolbox of structural biology has been augmented by other physical techniques, including nuclear magnetic resonance spectroscopy, electron microscopy, and solution scattering of X-rays and neutrons. Together these have transformed our understanding of the molecular basis of life. Here I review the major and most recent developments in structural biology that have brought us to the threshold of a landscape of astonishing molecular complexity.
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Affiliation(s)
- Stephen Curry
- Department of Life Sciences, Imperial College London, UK
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36
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Structural and Kinetic Characterization of Thymidine Kinase from Leishmania major. PLoS Negl Trop Dis 2015; 9:e0003781. [PMID: 25978379 PMCID: PMC4433323 DOI: 10.1371/journal.pntd.0003781] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 04/23/2015] [Indexed: 01/17/2023] Open
Abstract
Leishmania spp. is a protozoan parasite and the causative agent of leishmaniasis. Thymidine kinase (TK) catalyses the transfer of the γ-phosphate of ATP to 2’-deoxythymidine (dThd) forming thymidine monophosphate (dTMP). L. major Type II TK (LmTK) has been previously shown to be important for infectivity of the parasite and therefore has potential as a drug target for anti-leishmanial therapy. In this study, we determined the enzymatic properties and the 3D structures of holo forms of the enzyme. LmTK efficiently phosphorylates dThd and dUrd and has high structural homology to TKs from other species. However, it significantly differs in its kinetic properties from Trypanosoma brucei TK since purines are not substrates of the enzyme and dNTPs such as dUTP inhibit LmTK. The enzyme had Km and kcat values for dThd of 1.1 μM and 2.62 s-1 and exhibits cooperative binding for ATP. Additionally, we show that the anti-retroviral prodrug zidovudine (3-azido-3-deoxythymidine, AZT) and 5’-modified dUrd can be readily phosphorylated by LmTK. The production of recombinant enzyme at a level suitable for structural studies was achieved by the construction of C-terminal truncated versions of the enzyme and the use of a baculoviral expression system. The structures of the catalytic core of LmTK in complex with dThd, the negative feedback regulator dTTP and the bi-substrate analogue AP5dT, were determined to 2.74, 3.00 and 2.40 Å, respectively, and provide the structural basis for exclusion of purines and dNTP inhibition. The results will aid the process of rational drug design with LmTK as a potential target for anti-leishmanial drugs. The DNA within the genome of an organism encodes all the information, firstly for reproduction and secondly for translation into proteins—the workhorses of a biological cell. Proteins carry out a host of essential biological activities within the cell. A full understanding of a protein now requires determination of a wide range of its properties in solution in the cell and in vitro in solution, but in addition, its 3D structure usually determined by X-ray crystallography. Leishmania species are a family of protozoan parasites of humans and the causative agent of leishmaniasis, a major health concern in the developing world. Selective inhibition of key enzymes in these parasites is a key route for combating these diseases. We have focused our work on thymidine kinase, an important enzyme from Leishmania major, and a potential target for the development of new drugs. We have carried out kinetic studies of the enzyme’s activity in solution and determined its 3D crystal structure, enabling rational drug design.
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The crystal structure and small-angle X-ray analysis of CsdL/TcdA reveal a new tRNA binding motif in the MoeB/E1 superfamily. PLoS One 2015; 10:e0118606. [PMID: 25897750 PMCID: PMC4405576 DOI: 10.1371/journal.pone.0118606] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Accepted: 01/21/2015] [Indexed: 11/19/2022] Open
Abstract
Cyclic N6-threonylcarbamoyladenosine ('cyclic t6A', ct(6)A) is a non-thiolated hypermodification found in transfer RNAs (tRNAs) in bacteria, protists, fungi and plants. In bacteria and yeast cells ct(6)A has been shown to enhance translation fidelity and efficiency of ANN codons by improving the faithful discrimination of aminoacylated tRNAs by the ribosome. To further the understanding of ct(6)A biology we have determined the high-resolution crystal structures of CsdL/TcdA in complex with AMP and ATP, an E1-like activating enzyme from Escherichia coli, which catalyzes the ATP-dependent dehydration of t6A to form ct(6)A. CsdL/TcdA is a dimer whose structural integrity and dimer interface depend critically on strongly bound K+ and Na+ cations. By using biochemical assays and small-angle X-ray scattering we show that CsdL/TcdA can associate with tRNA with a 1:1 stoichiometry and with the proper position and orientation for the cyclization of t6A. Furthermore, we show by nuclear magnetic resonance that CsdL/TcdA engages in transient interactions with CsdA and CsdE, which, in the latter case, involve catalytically important residues. These short-lived interactions may underpin the precise channeling of sulfur atoms from cysteine to CsdL/TcdA as previously characterized. In summary, the combination of structural, biophysical and biochemical methods applied to CsdL/TcdA has afforded a more thorough understanding of how the structure of this E1-like enzyme has been fine tuned to accomplish ct(6)A synthesis on tRNAs while providing support for the notion that CsdA and CsdE are able to functionally interact with CsdL/TcdA.
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Electrostatic effects in the folding of the SH3 domain of the c-Src tyrosine kinase: pH-dependence in 3D-domain swapping and amyloid formation. PLoS One 2014; 9:e113224. [PMID: 25490095 PMCID: PMC4260792 DOI: 10.1371/journal.pone.0113224] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 10/20/2014] [Indexed: 11/19/2022] Open
Abstract
The SH3 domain of the c-Src tyrosine kinase (c-Src-SH3) aggregates to form intertwined dimers and amyloid fibrils at mild acid pHs. In this work, we show that a single mutation of residue Gln128 of this SH3 domain has a significant effect on: (i) its thermal stability; and (ii) its propensity to form amyloid fibrils. The Gln128Glu mutant forms amyloid fibrils at neutral pH but not at mild acid pH, while Gln128Lys and Gln128Arg mutants do not form these aggregates under any of the conditions assayed. We have also solved the crystallographic structures of the wild-type (WT) and Gln128Glu, Gln128Lys and Gln128Arg mutants from crystals obtained at different pHs. At pH 5.0, crystals belong to the hexagonal space group P6522 and the asymmetric unit is formed by one chain of the protomer of the c-Src-SH3 domain in an open conformation. At pH 7.0, crystals belong to the orthorhombic space group P212121, with two molecules at the asymmetric unit showing the characteristic fold of the SH3 domain. Analysis of these crystallographic structures shows that the residue at position 128 is connected to Glu106 at the diverging β-turn through a cluster of water molecules. Changes in this hydrogen-bond network lead to the displacement of the c-Src-SH3 distal loop, resulting also in conformational changes of Leu100 that might be related to the binding of proline rich motifs. Our findings show that electrostatic interactions and solvation of residues close to the folding nucleation site of the c-Src-SH3 domain might play an important role during the folding reaction and the amyloid fibril formation.
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Baskaran K, Duarte JM, Biyani N, Bliven S, Capitani G. A PDB-wide, evolution-based assessment of protein-protein interfaces. BMC STRUCTURAL BIOLOGY 2014; 14:22. [PMID: 25326082 PMCID: PMC4274722 DOI: 10.1186/s12900-014-0022-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 09/25/2014] [Indexed: 12/04/2022]
Abstract
Background Thanks to the growth in sequence and structure databases, more than 50 million sequences are now available in UniProt and 100,000 structures in the PDB. Rich information about protein–protein interfaces can be obtained by a comprehensive study of protein contacts in the PDB, their sequence conservation and geometric features. Results An automated computational pipeline was developed to run our Evolutionary Protein–Protein Interface Classifier (EPPIC) software on the entire PDB and store the results in a relational database, currently containing > 800,000 interfaces. This allows the analysis of interface data on a PDB-wide scale. Two large benchmark datasets of biological interfaces and crystal contacts, each containing about 3000 entries, were automatically generated based on criteria thought to be strong indicators of interface type. The BioMany set of biological interfaces includes NMR dimers solved as crystal structures and interfaces that are preserved across diverse crystal forms, as catalogued by the Protein Common Interface Database (ProtCID) from Xu and Dunbrack. The second dataset, XtalMany, is derived from interfaces that would lead to infinite assemblies and are therefore crystal contacts. BioMany and XtalMany were used to benchmark the EPPIC approach. The performance of EPPIC was also compared to classifications from the Protein Interfaces, Surfaces, and Assemblies (PISA) program on a PDB-wide scale, finding that the two approaches give the same call in about 88% of PDB interfaces. By comparing our safest predictions to the PDB author annotations, we provide a lower-bound estimate of the error rate of biological unit annotations in the PDB. Additionally, we developed a PyMOL plugin for direct download and easy visualization of EPPIC interfaces for any PDB entry. Both the datasets and the PyMOL plugin are available at http://www.eppic-web.org/ewui/#downloads. Conclusions Our computational pipeline allows us to analyze protein–protein contacts and their sequence conservation across the entire PDB. Two new benchmark datasets are provided, which are over an order of magnitude larger than existing manually curated ones. These tools enable the comprehensive study of several aspects of protein–protein contacts in the PDB and represent a basis for future, even larger scale studies of protein–protein interactions.
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Dunne M, Mertens HDT, Garefalaki V, Jeffries CM, Thompson A, Lemke EA, Svergun DI, Mayer MJ, Narbad A, Meijers R. The CD27L and CTP1L endolysins targeting Clostridia contain a built-in trigger and release factor. PLoS Pathog 2014; 10:e1004228. [PMID: 25058163 PMCID: PMC4110038 DOI: 10.1371/journal.ppat.1004228] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 05/19/2014] [Indexed: 02/04/2023] Open
Abstract
The bacteriophage ΦCD27 is capable of lysing Clostridium difficile, a pathogenic bacterium that is a major cause for nosocomial infection. A recombinant CD27L endolysin lyses C. difficile in vitro, and represents a promising alternative as a bactericide. To better understand the lysis mechanism, we have determined the crystal structure of an autoproteolytic fragment of the CD27L endolysin. The structure covers the C-terminal domain of the endolysin, and represents a novel fold that is identified in a number of lysins that target Clostridia bacteria. The structure indicates endolysin cleavage occurs at the stem of the linker connecting the catalytic domain with the C-terminal domain. We also solved the crystal structure of the C-terminal domain of a slow cleaving mutant of the CTP1L endolysin that targets C. tyrobutyricum. Two distinct dimerization modes are observed in the crystal structures for both endolysins, despite a sequence identity of only 22% between the domains. The dimers are validated to be present for the full length protein in solution by right angle light scattering, small angle X-ray scattering and cross-linking experiments using the cross-linking amino acid p-benzoyl-L-phenylalanine (pBpa). Mutagenesis on residues contributing to the dimer interfaces indicates that there is a link between the dimerization modes and the autocleavage mechanism. We show that for the CTP1L endolysin, there is a reduction in lysis efficiency that is proportional to the cleavage efficiency. We propose a model for endolysin triggering, where the extended dimer presents the inactive state, and a switch to the side-by-side dimer triggers the cleavage of the C-terminal domain. This leads to the release of the catalytic portion of the endolysin, enabling the efficient digestion of the bacterial cell wall. Clostridium difficile infection is a common cause of hospital-acquired diarrhea, following broad-spectrum antibiotic treatment particularly in elderly patients. Bacteriophage therapy could provide an alternative treatment, but a better understanding of the viral components that lyse the bacterial cell is necessary. Here, we report on the activation of two endolysins from bacteriophages that lyse Clostridia. The structures of autoproteolytic fragments of two endolysins were determined by X-ray crystallography. Based on the structures, we introduced mutations that affect the autolytic cleavage of the enzymatic portion of the endolysins, and we show that two oligomeric states have an effect on the cleavage mechanism. Moreover, the lysis activity is affected when autocleavage is inhibited for one endolysin. We propose that the cleavage and oligomerization are linked, and they provide the endolysin with a trigger and release mechanism that leads to activation. The identification of a trigger and release factor may not only be relevant to Clostridia endolysins, but could be an important factor in the triggering of many bacteriophage endolysins. A fuller understanding of this activation mechanism will help in the design of recombinant endolysins or bacteriophages with a more efficient therapeutic potential.
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Affiliation(s)
- Matthew Dunne
- European Molecular Biology Laboratory (EMBL), Hamburg, Germany
| | | | | | - Cy M. Jeffries
- European Molecular Biology Laboratory (EMBL), Hamburg, Germany
| | - Andrew Thompson
- Synchrotron Soleil, L'Orme des Merisiers, Saint Aubin, Gif sur Yvette, France
| | - Edward A. Lemke
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | | | - Melinda J. Mayer
- Institute of Food Research, Colney, Norwich, United Kingdom
- * E-mail: (MJM); (RM)
| | - Arjan Narbad
- Institute of Food Research, Colney, Norwich, United Kingdom
| | - Rob Meijers
- European Molecular Biology Laboratory (EMBL), Hamburg, Germany
- * E-mail: (MJM); (RM)
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Zorzini V, Buts L, Sleutel M, Garcia-Pino A, Talavera A, Haesaerts S, De Greve H, Cheung A, van Nuland NAJ, Loris R. Structural and biophysical characterization of Staphylococcus aureus SaMazF shows conservation of functional dynamics. Nucleic Acids Res 2014; 42:6709-25. [PMID: 24748664 PMCID: PMC4041440 DOI: 10.1093/nar/gku266] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 03/18/2014] [Accepted: 03/19/2014] [Indexed: 01/19/2023] Open
Abstract
The Staphylococcus aureus genome contains three toxin-antitoxin modules, including one mazEF module, SamazEF. Using an on-column separation protocol we are able to obtain large amounts of wild-type SaMazF toxin. The protein is well-folded and highly resistant against thermal unfolding but aggregates at elevated temperatures. Crystallographic and nuclear magnetic resonance (NMR) solution studies show a well-defined dimer. Differences in structure and dynamics between the X-ray and NMR structural ensembles are found in three loop regions, two of which undergo motions that are of functional relevance. The same segments also show functionally relevant dynamics in the distantly related CcdB family despite divergence of function. NMR chemical shift mapping and analysis of residue conservation in the MazF family suggests a conserved mode for the inhibition of MazF by MazE.
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Affiliation(s)
- Valentina Zorzini
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium Molecular Recognition Unit, Department of Structural Biology, VIB, Pleinlaan 2, 1050 Brussels, Belgium
| | - Lieven Buts
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium Molecular Recognition Unit, Department of Structural Biology, VIB, Pleinlaan 2, 1050 Brussels, Belgium
| | - Mike Sleutel
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
| | - Abel Garcia-Pino
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium Molecular Recognition Unit, Department of Structural Biology, VIB, Pleinlaan 2, 1050 Brussels, Belgium
| | - Ariel Talavera
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium Molecular Recognition Unit, Department of Structural Biology, VIB, Pleinlaan 2, 1050 Brussels, Belgium
| | - Sarah Haesaerts
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium Molecular Recognition Unit, Department of Structural Biology, VIB, Pleinlaan 2, 1050 Brussels, Belgium
| | - Henri De Greve
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium Molecular Recognition Unit, Department of Structural Biology, VIB, Pleinlaan 2, 1050 Brussels, Belgium
| | - Ambrose Cheung
- Department of Microbiology and Immunology, Dartmouth Medical School, Hanover, NH 03755, USA
| | - Nico A J van Nuland
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium Molecular Recognition Unit, Department of Structural Biology, VIB, Pleinlaan 2, 1050 Brussels, Belgium
| | - Remy Loris
- Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium Molecular Recognition Unit, Department of Structural Biology, VIB, Pleinlaan 2, 1050 Brussels, Belgium
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Cámara-Artigas A, Martínez-Rodríguez S, Ortiz-Salmerón E, Martín-García JM. 3D domain swapping in a chimeric c-Src SH3 domain takes place through two hinge loops. J Struct Biol 2014; 186:195-203. [DOI: 10.1016/j.jsb.2014.02.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2013] [Revised: 02/10/2014] [Accepted: 02/11/2014] [Indexed: 11/29/2022]
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Gutmanas A, Oldfield TJ, Patwardhan A, Sen S, Velankar S, Kleywegt GJ. The role of structural bioinformatics resources in the era of integrative structural biology. ACTA CRYSTALLOGRAPHICA. SECTION D, BIOLOGICAL CRYSTALLOGRAPHY 2013; 69:710-21. [PMID: 23633580 PMCID: PMC3640467 DOI: 10.1107/s0907444913001157] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Accepted: 01/11/2013] [Indexed: 11/10/2022]
Abstract
The history and the current state of the PDB and EMDB archives is briefly described, as well as some of the challenges that they face. It seems natural that the role of structural biology archives will change from being a pure repository of historic data into becoming an indispensable resource for the wider biomedical community. As part of this transformation, it will be necessary to validate the biomacromolecular structure data and ensure the highest possible quality for the archive holdings, to combine structural data from different spatial scales into a unified resource and to integrate structural data with functional, genetic and taxonomic data as well as other information available in bioinformatics resources. Some recent developments and plans to address these challenges at PDBe are presented.
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Affiliation(s)
- Aleksandras Gutmanas
- Protein Data Bank in Europe, EMBL–EBI, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SD, England
| | - Thomas J. Oldfield
- Protein Data Bank in Europe, EMBL–EBI, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SD, England
| | - Ardan Patwardhan
- Protein Data Bank in Europe, EMBL–EBI, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SD, England
| | - Sanchayita Sen
- Protein Data Bank in Europe, EMBL–EBI, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SD, England
| | - Sameer Velankar
- Protein Data Bank in Europe, EMBL–EBI, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SD, England
| | - Gerard J. Kleywegt
- Protein Data Bank in Europe, EMBL–EBI, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SD, England
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Bacarizo J, Camara-Artigas A. Atomic resolution structures of the c-Src SH3 domain in complex with two high-affinity peptides from classes I and II. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2013; 69:756-66. [PMID: 23633584 DOI: 10.1107/s0907444913001522] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Accepted: 01/15/2013] [Indexed: 12/20/2022]
Abstract
The atomic resolution crystal structures of complexes between the SH3 domain of the c-Src tyrosine kinase and two high-affinity peptides belonging to class I and class II have been solved. The crystals of the Thr98Asp and Thr98Glu mutants in complex with the APP12 peptide (APPLPPRNRPRL) belonged to the trigonal space group P3121 and in both cases the asymmetric unit was composed of one molecule of the SH3-APP12 complex. The crystals of the Thr98Glu mutant in complex with the VSL12 peptide (VSLARRPLPLP) belonged to the trigonal space group P3221 and the asymmetric unit was also composed of a single molecule of the SH3-VSL12 complex. All crystals were obtained in the presence of PEG 300 under the same conditions as reported for the intertwined dimeric structure of the c-Src SH3 domain, but the presence of the peptide stabilizes the monomeric form of the domain. These structures allow a detailed analysis of the role of salt bridges, cation-π interactions and hydrogen bonds in the binding of proline-rich motifs to the c-Src SH3 domain. Moreover, these crystallographic structures allow the role of water molecules in the binding of these motifs to the c-Src SH3 domain to be studied for the first time.
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Affiliation(s)
- Julio Bacarizo
- Department of Chemistry and Physics, University of Almería, Agrifood Campus of International Excellence, Carretera de Sacramento, 04120 Almería, Spain
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Van der Meeren R, Wen Y, Van Gelder P, Tommassen J, Devreese B, Savvides SN. New insights into the assembly of bacterial secretins: structural studies of the periplasmic domain of XcpQ from Pseudomonas aeruginosa. J Biol Chem 2012. [PMID: 23188826 DOI: 10.1074/jbc.m112.432096] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The type II secretion system is a multiprotein assembly spanning the inner and outer membranes in Gram-negative bacteria. It is found in almost all pathogenic bacteria where it contributes to virulence, host tissue colonization, and infection. The exoproteins are secreted across the outer membrane via a large translocation channel, the secretin, which typically adopts a dodecameric structure. These secretin channels have large periplasmic N-terminal domains that reach out into the periplasm for communication with the inner membrane platform and with a pseudopilus structure that spans the periplasm. Here we report the crystal structure of the N-terminal periplasmic domain of the secretin XcpQ from Pseudomonas aeruginosa, revealing a two-lobe dimeric assembly featuring parallel subunits engaging in well defined interactions at the tips of each lobe. We have employed structure-based engineering of disulfide bridges and native mass spectrometry to show that the periplasmic domain of XcpQ dimerizes in a concentration-dependent manner. Validation of these insights in the context of cellular full-length XcpQ and further evaluation of the functionality of disulfide-linked XcpQ establishes that the basic oligomerization unit of XcpQ is a dimer. This is consistent with the notion that the dodecameric secretin assembles as a hexamer of dimers to ensure correct projection of the N-terminal domains into the periplasm. Therefore, our studies provide a key conceptual advancement in understanding the assembly principles and dynamic function of type II secretion system secretins and challenge recent studies reporting monomers as the basic subunit of the secretin oligomer.
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Knapp K, Zebisch M, Pippel J, El-Tayeb A, Müller CE, Sträter N. Crystal structure of the human ecto-5'-nucleotidase (CD73): insights into the regulation of purinergic signaling. Structure 2012; 20:2161-73. [PMID: 23142347 DOI: 10.1016/j.str.2012.10.001] [Citation(s) in RCA: 144] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Revised: 09/26/2012] [Accepted: 10/04/2012] [Indexed: 01/11/2023]
Abstract
In vertebrates ecto-5'-nucleotidase (e5NT) catalyzes the hydrolysis of extracellular AMP to adenosine and represents the major control point for extracellular adenosine levels. Due to its pivotal role for activation of P1 adenosine receptors, e5NT has emerged as an appealing drug target for treatment of inflammation, chronic pain, hypoxia, and cancer. Crystal structures of the dimeric human e5NT reveal an extensive 114° conformational switch between the open and closed forms of the enzyme. The dimerization interface is formed by the C-terminal domains and exhibits interchain motions of up to 13°. Complex structures with adenosine and AMPCP indicate that structural control of the domain movement determines the selectivity for monophosphate nucleotides. Binding modes of nucleotide-derived and flavonoid-based compounds complexed to the C-terminal domain in the open form reveal an additional binding pocket of ∼210 Å(3) that might be explored to design more potent inhibitors.
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Affiliation(s)
- Karen Knapp
- Institute of Bioanalytical Chemistry, Center for Biotechnology and Biomedicine, University of Leipzig, Deutscher Platz 5, 04103 Leipzig, Germany
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Erdemli SB, Gupta R, Bishai WR, Lamichhane G, Amzel LM, Bianchet MA. Targeting the cell wall of Mycobacterium tuberculosis: structure and mechanism of L,D-transpeptidase 2. Structure 2012; 20:2103-15. [PMID: 23103390 DOI: 10.1016/j.str.2012.09.016] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 09/26/2012] [Accepted: 09/26/2012] [Indexed: 01/08/2023]
Abstract
With multidrug-resistant cases of tuberculosis increasing globally, better antibiotic drugs and novel drug targets are becoming an urgent need. Traditional β-lactam antibiotics that inhibit D,D-transpeptidases are not effective against mycobacteria, in part because mycobacteria rely mostly on L,D-transpeptidases for biosynthesis and maintenance of their peptidoglycan layer. This reliance plays a major role in drug resistance and persistence of Mycobacterium tuberculosis (Mtb) infections. The crystal structure at 1.7 Å resolution of the Mtb L,D-transpeptidase Ldt(Mt2) containing a bound peptidoglycan fragment, reported here, provides information about catalytic site organization as well as substrate recognition by the enzyme. Based on our structural, kinetic, and calorimetric data, we propose a catalytic mechanism for Ldt(Mt2) in which both acyl-acceptor and acyl-donor substrates reach the catalytic site from the same, rather than different, entrances. Together, this information provides vital insights to facilitate development of drugs targeting this validated yet unexploited enzyme.
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Affiliation(s)
- Sabri B Erdemli
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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Niemann HH, Gherardi E, Bleymüller WM, Heinz DW. Engineered variants of InlB with an additional leucine-rich repeat discriminate between physiologically relevant and packing contacts in crystal structures of the InlB:MET complex. Protein Sci 2012; 21:1528-39. [PMID: 22887347 PMCID: PMC3526994 DOI: 10.1002/pro.2142] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Revised: 08/01/2012] [Accepted: 08/06/2012] [Indexed: 11/07/2022]
Abstract
The physiological relevance of contacts in crystal lattices often remains elusive. This was also the case for the complex between the invasion protein internalin B (InlB) from Listeria monocytogenes and its host cell receptor, the human receptor tyrosine kinase (RTK) MET. InlB is a MET agonist and induces bacterial host cell invasion. Activation of RTKs generally involves ligand-induced dimerization of the receptor ectodomain. The two currently available crystal structures of the InlB:MET complex show the same arrangement of InlB and MET in a 1:1 complex, but different dimeric 2:2 assemblies. Only one of these 2:2 assemblies is predicted to be stable by a computational procedure. This assembly is mainly stabilized by a contact between the Cap domain of InlB from one and the Sema domain of MET from another 1:1 complex. Here, we probe the physiological relevance of this interaction. We generated variants of the leucine-rich repeat (LRR) protein InlB by inserting an additional repeat between the first and the second LRR. This should allow formation of the 1:1 complex but disrupt the potential 2:2 complex involving the Cap-Sema contact due to steric distortions. A crystal structure of one of the engineered proteins showed that it folded properly. Binding affinity to MET was comparable to that of wild-type InlB. The InlB variant induced MET phosphorylation and cell scatter like wild-type InlB. These results suggest that the Cap-Sema interaction is not physiologically relevant and support the previously proposed assembly, in which a 2:2 InlB:MET complex is built around a ligand dimer.
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Affiliation(s)
- Hartmut H Niemann
- Department of Chemistry, Bielefeld University, 33501 Bielefeld, Germany.
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Abstract
The specific self-association of proteins to form homodimers and higher order oligomers is an extremely common event in biological systems. In this chapter we review the prevalence of protein oligomerization and discuss the likely origins of this phenomenon. We also outline many of the functional advantages conferred by the dimerization or oligomerization of a wide range of different proteins and in a variety of biological roles, that are likely to have placed a selective pressure on biological systems to evolve and maintain homodimerization/oligomerization interfaces.
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