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Kovermann M, Stefan A, Palazzetti C, Immler F, Dal Piaz F, Bernardi L, Cimone V, Bellone ML, Hochkoeppler A. The Mycobacterium tuberculosis protein tyrosine phosphatase MptpA features a pH dependent activity overlapping the bacterium sensitivity to acidic conditions. Biochimie 2023; 213:66-81. [PMID: 37201648 DOI: 10.1016/j.biochi.2023.04.014] [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: 02/09/2023] [Revised: 04/03/2023] [Accepted: 04/24/2023] [Indexed: 05/20/2023]
Abstract
The Mycobacterium tuberculosis low-molecular weight protein tyrosine phosphatase (MptpA) is responsible for the inhibition of phagosome-lysosome fusion and is essential for the bacterium pathogenicity. This inhibition implies that M. tuberculosis is not exposed to a strongly acidic environment in vivo, enabling successful propagation in host cells. Remarkably, MptpA has been previously structurally and functionally investigated, with special emphasis devoted to the enzyme properties at pH 8.0. Considering that the virulence of M. tuberculosis is strictly dependent on the avoidance of acidic conditions in vivo, we analysed the pH-dependence of the structural and catalytic properties of MptpA. Here we show that this enzyme undergoes pronounced conformational rearrangements when exposed to acidic pH conditions, inducing a severe decrease of the enzymatic catalytic efficiency at the expense of phosphotyrosine (pTyr). In particular, a mild decrease of pH from 6.5 to 6.0 triggers a significant increase of K0.5 of MptpA for phosphotyrosine, the phosphate group of which we determined to feature a pKa2 equal to 5.7. Surface plasmon resonance experiments confirmed that MptpA binds poorly to pTyr at pH values < 6.5. Notably, the effectiveness of the MptpA competitive inhibitor L335-M34 at pH 6 does largely outperform the inhibition exerted at neutral or alkaline pH values. Overall, our observations indicate a pronounced sensitivity of MptpA to acidic pH conditions, and suggest the search for competitive inhibitors bearing a negatively charged group featuring pKa values lower than that of the substrate phosphate group.
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Affiliation(s)
- Michael Kovermann
- Department of Chemistry, University of Konstanz, Universitätstraße 10, 78464, Konstanz, Germany
| | - Alessandra Stefan
- Department of Pharmacy and Biotechnology, University of Bologna, Viale Risorgimento 4, 40136, Bologna, Italy; CSGI, University of Florence, Via della Lastruccia 3, 50019, Sesto Fiorentino, Firenze, Italy
| | - Chiara Palazzetti
- Department of Pharmacy and Biotechnology, University of Bologna, Viale Risorgimento 4, 40136, Bologna, Italy
| | - Fabian Immler
- Department of Chemistry, University of Konstanz, Universitätstraße 10, 78464, Konstanz, Germany
| | - Fabrizio Dal Piaz
- Department of Medicine, University of Salerno, Via Giovanni Paolo II 132, 84084, Fisciano, Italy
| | - Luca Bernardi
- Department of Industrial Chemistry "Toson Montanaro", University of Bologna, Viale Risorgimento 4, 40136, Bologna, Italy
| | - Valentina Cimone
- Department of Pharmacy and Biotechnology, University of Bologna, Viale Risorgimento 4, 40136, Bologna, Italy
| | - Maria Laura Bellone
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II 132, 84084, Fisciano, Italy
| | - Alejandro Hochkoeppler
- Department of Pharmacy and Biotechnology, University of Bologna, Viale Risorgimento 4, 40136, Bologna, Italy; CSGI, University of Florence, Via della Lastruccia 3, 50019, Sesto Fiorentino, Firenze, Italy.
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2
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Chatterjee A. Mycobacterium tuberculosis and its secreted tyrosine phosphatases. Biochimie 2023; 212:41-47. [PMID: 37059349 DOI: 10.1016/j.biochi.2023.04.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 04/04/2023] [Accepted: 04/12/2023] [Indexed: 04/16/2023]
Abstract
Tuberculosis is one of the most common infectious diseases and has been a major burden for a long time now. Increasing drug resistance in TB is slowing down the process of disease treatment. Mycobacterium tuberculosis, the causative agent of TB is known to have a cascade of virulence factors to fight with host's immune system. The phosphatases (PTPs) of Mtb plays a critical role as these are secretory in nature and help the survival of bacteria in host. Researchers have been trying to synthesize inhibitors against a lot of virulence factors of Mtb but recently the phosphatases have gained a lot of interest due to their secretory nature. This review gives a concise overview of virulence factors of Mtb with emphasis on mPTPs. Here we discuss the current scenario of drug development against mPTPs.
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Affiliation(s)
- Aditi Chatterjee
- University of Maryland Greenebaum Comprehensive Cancer Center, Baltimore, MD, USA.
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3
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Campos PC, Cunha DT, Souza-Costa LP, Shiloh MU, Franco LH. Bag it, tag it: ubiquitin ligases and host resistance to Mycobacterium tuberculosis. Trends Microbiol 2022; 30:973-985. [PMID: 35491351 PMCID: PMC9474620 DOI: 10.1016/j.tim.2022.03.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/26/2022] [Accepted: 03/29/2022] [Indexed: 11/29/2022]
Abstract
Infection with Mycobacterium tuberculosis (Mtb), the etiological agent of tuberculosis (TB), remains a significant global epidemic. Host resistance to Mtb depends on both adaptive and innate immunity mechanisms, including development of antigen-specific CD4 and CD8 T cells, production of inflammatory cytokines, bacterial phagocytosis and destruction within phagolysosomes, host cell apoptosis, and autophagy. A key regulatory mechanism in innate immunity is the attachment of the small protein ubiquitin to protein and lipid targets by the enzymatic activity of ubiquitin ligases. Here, we summarize the latest advances on the role of ubiquitination and ubiquitin ligases in host immunity against Mtb, with a focus on innate immunity signaling, inflammation, and antimicrobial autophagy. Understanding how ubiquitin ligases mediate immunity to Mtb, and the specific substrates of distinct ubiquitin ligases in the context of Mtb infection, could facilitate development of new host-directed antimicrobials.
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Affiliation(s)
- Priscila C Campos
- Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9113, USA
| | - Danielle T Cunha
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Pres. Antônio Carlos, 6627, Belo Horizonte, MG 31270-901, Brazil
| | - Luiz P Souza-Costa
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Pres. Antônio Carlos, 6627, Belo Horizonte, MG 31270-901, Brazil
| | - Michael U Shiloh
- Department of Internal Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9113, USA; Department of Microbiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9113, USA.
| | - Luis H Franco
- Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Pres. Antônio Carlos, 6627, Belo Horizonte, MG 31270-901, Brazil.
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4
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Maschietto F, Zavala E, Allen B, Loria JP, Batista V. MptpA Kinetics Enhanced by Allosteric Control of an Active Conformation. J Mol Biol 2022; 434:167540. [PMID: 35339563 PMCID: PMC10623291 DOI: 10.1016/j.jmb.2022.167540] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 03/07/2022] [Accepted: 03/08/2022] [Indexed: 10/18/2022]
Abstract
Understanding allostery in the Mycobacterium tuberculosis low molecular weight protein tyrosine phosphatase (MptpA) is a subject of great interest since MptpA is one of two protein tyrosine phosphatases (PTPs) from the pathogenic organism Mycobacterium tuberculosis expressed during host cell infection. Here, we combine computational modeling with solution NMR spectroscopy and we find that Q75 is an allosteric site. Removal of the polar side chain of Q75 by mutation to leucine results in a cascade of events that reposition the acid loop over the active site and relocates the catalytic aspartic acid (D126) at an optimal position for proton donation to the leaving aryl group of the substrate and for subsequent hydrolysis of the thiophosphoryl intermediate. The computational analysis is consistent with kinetic data, and NMR spectroscopy, showing that the Q75L mutant exhibits enhanced reaction kinetics with similar substrate binding affinity. We anticipate that our findings will motivate further studies on the possibility that MptpA remains passivated during the chronic state of infection and increases its activity as part of the pathogenic life cycle of M. tuberculosis possibly via allosteric means.
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Affiliation(s)
- Federica Maschietto
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, CT 06520, United States
| | - Erik Zavala
- Department of Molecular Biophysics and Biochemistry, Yale University, 266 Whitney Avenue, New Haven, CT 06520, United States
| | - Brandon Allen
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, CT 06520, United States
| | - J Patrick Loria
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, CT 06520, United States; Department of Molecular Biophysics and Biochemistry, Yale University, 266 Whitney Avenue, New Haven, CT 06520, United States.
| | - Victor Batista
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, CT 06520, United States.
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5
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Golichenari B, Yari S, Tasbiti AH, Behravan J, Vaziri F, Ghazvini K. First conjugation directed traverse of gene cassettes harboring α1,3GT from fast-growing Mycobacterium smegmatis mc2 155 to slow-growing pathogen Mycobacterium tuberculosis H37Rv, presumably opening up new scopes in tuberculosis treatment. Enzyme Microb Technol 2022; 156:110003. [DOI: 10.1016/j.enzmictec.2022.110003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 01/02/2022] [Accepted: 01/31/2022] [Indexed: 11/03/2022]
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6
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Vaughn B, Abu Kwaik Y. Idiosyncratic Biogenesis of Intracellular Pathogens-Containing Vacuoles. Front Cell Infect Microbiol 2021; 11:722433. [PMID: 34858868 PMCID: PMC8632064 DOI: 10.3389/fcimb.2021.722433] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 10/25/2021] [Indexed: 12/12/2022] Open
Abstract
While most bacterial species taken up by macrophages are degraded through processing of the bacteria-containing vacuole through the endosomal-lysosomal degradation pathway, intravacuolar pathogens have evolved to evade degradation through the endosomal-lysosomal pathway. All intra-vacuolar pathogens possess specialized secretion systems (T3SS-T7SS) that inject effector proteins into the host cell cytosol to modulate myriad of host cell processes and remodel their vacuoles into proliferative niches. Although intravacuolar pathogens utilize similar secretion systems to interfere with their vacuole biogenesis, each pathogen has evolved a unique toolbox of protein effectors injected into the host cell to interact with, and modulate, distinct host cell targets. Thus, intravacuolar pathogens have evolved clear idiosyncrasies in their interference with their vacuole biogenesis to generate a unique intravacuolar niche suitable for their own proliferation. While there has been a quantum leap in our knowledge of modulation of phagosome biogenesis by intravacuolar pathogens, the detailed biochemical and cellular processes affected remain to be deciphered. Here we discuss how the intravacuolar bacterial pathogens Salmonella, Chlamydia, Mycobacteria, Legionella, Brucella, Coxiella, and Anaplasma utilize their unique set of effectors injected into the host cell to interfere with endocytic, exocytic, and ER-to-Golgi vesicle traffic. However, Coxiella is the main exception for a bacterial pathogen that proliferates within the hydrolytic lysosomal compartment, but its T4SS is essential for adaptation and proliferation within the lysosomal-like vacuole.
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Affiliation(s)
- Bethany Vaughn
- Department of Microbiology and Immunology, University of Louisville, Louisville, KY, United States
| | - Yousef Abu Kwaik
- Department of Microbiology and Immunology, University of Louisville, Louisville, KY, United States.,Center for Predictive Medicine, College of Medicine, University of Louisville, Louisville, KY, United States
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7
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SAVALAS LRT, LESTARİ A, MUNİRAH M, FARİDA S, SUHENDRA D, ASNAWATİ D, 'ARDHUHA J, SARI NİNGSİH B, SYAHRİ J. cis-2 and trans-2-eicosenoic Fatty Acids Inhibit Mycobacterium tuberculosis Virulence Factor Protein Tyrosine Phosphatase B. JOURNAL OF THE TURKISH CHEMICAL SOCIETY, SECTION A: CHEMISTRY 2021. [DOI: 10.18596/jotcsa.896489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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8
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Fernández-Soto P, Casulli J, Solano-Castro D, Rodríguez-Fernández P, Jowitt TA, Travis MA, Cavet JS, Tabernero L. Discovery of uncompetitive inhibitors of SapM that compromise intracellular survival of Mycobacterium tuberculosis. Sci Rep 2021; 11:7667. [PMID: 33828158 PMCID: PMC8027839 DOI: 10.1038/s41598-021-87117-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 02/15/2021] [Indexed: 12/28/2022] Open
Abstract
SapM is a secreted virulence factor from Mycobacterium tuberculosis critical for pathogen survival and persistence inside the host. Its full potential as a target for tuberculosis treatment has not yet been exploited because of the lack of potent inhibitors available. By screening over 1500 small molecules, we have identified new potent and selective inhibitors of SapM with an uncompetitive mechanism of inhibition. The best inhibitors share a trihydroxy-benzene moiety essential for activity. Importantly, the inhibitors significantly reduce mycobacterial burden in infected human macrophages at 1 µM, and they are selective with respect to other mycobacterial and human phosphatases. The best inhibitor also reduces intracellular burden of Francisella tularensis, which secretes the virulence factor AcpA, a homologue of SapM, with the same mechanism of catalysis and inhibition. Our findings demonstrate that inhibition of SapM with small molecule inhibitors is efficient in reducing intracellular mycobacterial survival in host macrophages and confirm SapM as a potential therapeutic target. These initial compounds have favourable physico-chemical properties and provide a basis for exploration towards the development of new tuberculosis treatments. The efficacy of a SapM inhibitor in reducing Francisella tularensis intracellular burden suggests the potential for developing broad-spectrum antivirulence agents to treat microbial infections.
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Affiliation(s)
- Paulina Fernández-Soto
- School of Biological Sciences, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, M13 9PT, UK
| | - Joshua Casulli
- School of Biological Sciences, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, M13 9PT, UK.,Lydia Becker Institute for Immunology and Inflammation, University of Manchester, Manchester, UK.,Wellcome Centre for Cell-Matrix Research, University of Manchester, Manchester, UK
| | - Danilo Solano-Castro
- School of Biological Sciences, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, M13 9PT, UK
| | - Pablo Rodríguez-Fernández
- School of Biological Sciences, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, M13 9PT, UK
| | - Thomas A Jowitt
- School of Biological Sciences, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, M13 9PT, UK.,Wellcome Centre for Cell-Matrix Research, University of Manchester, Manchester, UK
| | - Mark A Travis
- School of Biological Sciences, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, M13 9PT, UK.,Lydia Becker Institute for Immunology and Inflammation, University of Manchester, Manchester, UK.,Wellcome Centre for Cell-Matrix Research, University of Manchester, Manchester, UK
| | - Jennifer S Cavet
- School of Biological Sciences, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, M13 9PT, UK
| | - Lydia Tabernero
- School of Biological Sciences, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, M13 9PT, UK. .,Lydia Becker Institute for Immunology and Inflammation, University of Manchester, Manchester, UK.
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9
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Alsayed SSR, Beh CC, Foster NR, Payne AD, Yu Y, Gunosewoyo H. Kinase Targets for Mycolic Acid Biosynthesis in Mycobacterium tuberculosis. Curr Mol Pharmacol 2019; 12:27-49. [PMID: 30360731 DOI: 10.2174/1874467211666181025141114] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 10/11/2018] [Accepted: 10/11/2018] [Indexed: 12/12/2022]
Abstract
BACKGROUND Mycolic acids (MAs) are the characteristic, integral building blocks for the mycomembrane belonging to the insidious bacterial pathogen Mycobacterium tuberculosis (M.tb). These C60-C90 long α-alkyl-β-hydroxylated fatty acids provide protection to the tubercle bacilli against the outside threats, thus allowing its survival, virulence and resistance to the current antibacterial agents. In the post-genomic era, progress has been made towards understanding the crucial enzymatic machineries involved in the biosynthesis of MAs in M.tb. However, gaps still remain in the exact role of the phosphorylation and dephosphorylation of regulatory mechanisms within these systems. To date, a total of 11 serine-threonine protein kinases (STPKs) are found in M.tb. Most enzymes implicated in the MAs synthesis were found to be phosphorylated in vitro and/or in vivo. For instance, phosphorylation of KasA, KasB, mtFabH, InhA, MabA, and FadD32 downregulated their enzymatic activity, while phosphorylation of VirS increased its enzymatic activity. These observations suggest that the kinases and phosphatases system could play a role in M.tb adaptive responses and survival mechanisms in the human host. As the mycobacterial STPKs do not share a high sequence homology to the human's, there have been some early drug discovery efforts towards developing potent and selective inhibitors. OBJECTIVE Recent updates to the kinases and phosphatases involved in the regulation of MAs biosynthesis will be presented in this mini-review, including their known small molecule inhibitors. CONCLUSION Mycobacterial kinases and phosphatases involved in the MAs regulation may serve as a useful avenue for antitubercular therapy.
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Affiliation(s)
- Shahinda S R Alsayed
- School of Pharmacy and Biomedical Sciences, Faculty of Health Sciences, Curtin University, Perth, WA 6102, Australia
| | - Chau C Beh
- Western Australia School of Mines: Minerals, Energy and Chemical Engineering, Curtin University, Bentley 6102 WA, Australia.,David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, United States
| | - Neil R Foster
- Western Australia School of Mines: Minerals, Energy and Chemical Engineering, Curtin University, Bentley 6102 WA, Australia
| | - Alan D Payne
- School of Molecular and Life Sciences, Curtin University, Perth, WA 6102, Australia
| | - Yu Yu
- School of Pharmacy and Biomedical Sciences, Faculty of Health Sciences, Curtin University, Perth, WA 6102, Australia
| | - Hendra Gunosewoyo
- School of Pharmacy and Biomedical Sciences, Faculty of Health Sciences, Curtin University, Perth, WA 6102, Australia
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10
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Stamm CE, Pasko BL, Chaisavaneeyakorn S, Franco LH, Nair VR, Weigele BA, Alto NM, Shiloh MU. Screening Mycobacterium tuberculosis Secreted Proteins Identifies Mpt64 as a Eukaryotic Membrane-Binding Bacterial Effector. mSphere 2019; 4:e00354-19. [PMID: 31167949 PMCID: PMC6553557 DOI: 10.1128/msphere.00354-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 05/19/2019] [Indexed: 02/07/2023] Open
Abstract
Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, is one of the most successful human pathogens. One reason for its success is that Mtb can reside within host macrophages, a cell type that normally functions to phagocytose and destroy infectious bacteria. However, Mtb is able to evade macrophage defenses in order to survive for prolonged periods of time. Many intracellular pathogens secrete virulence factors targeting host membranes and organelles to remodel their intracellular environmental niche. We hypothesized that Mtb secreted proteins that target host membranes are vital for Mtb to adapt to and manipulate the host environment for survival. Thus, we characterized 200 secreted proteins from Mtb for their ability to associate with eukaryotic membranes using a unique temperature-sensitive yeast screen and to manipulate host trafficking pathways using a modified inducible secretion screen. We identified five Mtb secreted proteins that both associated with eukaryotic membranes and altered the host secretory pathway. One of these secreted proteins, Mpt64, localized to the endoplasmic reticulum during Mtb infection of murine and human macrophages and impaired the unfolded protein response in macrophages. These data highlight the importance of secreted proteins in Mtb pathogenesis and provide a basis for further investigation into their molecular mechanisms.IMPORTANCE Advances have been made to identify secreted proteins of Mycobacterium tuberculosis during animal infections. These data, combined with transposon screens identifying genes important for M. tuberculosis virulence, have generated a vast resource of potential M. tuberculosis virulence proteins. However, the function of many of these proteins in M. tuberculosis pathogenesis remains elusive. We have integrated three cell biological screens to characterize nearly 200 M. tuberculosis secreted proteins for eukaryotic membrane binding, host subcellular localization, and interactions with host vesicular trafficking. In addition, we observed the localization of one secreted protein, Mpt64, to the endoplasmic reticulum (ER) during M. tuberculosis infection of macrophages. Interestingly, although Mpt64 is exported by the Sec pathway, its delivery into host cells was dependent upon the action of the type VII secretion system. Finally, we observed that Mpt64 impairs the ER-mediated unfolded protein response in macrophages.
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Affiliation(s)
- Chelsea E Stamm
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Breanna L Pasko
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Sujittra Chaisavaneeyakorn
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Luis H Franco
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Center for Autophagy Research, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Vidhya R Nair
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Bethany A Weigele
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Neal M Alto
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Michael U Shiloh
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
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11
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Protein tyrosine kinase, PtkA, is required for Mycobacterium tuberculosis growth in macrophages. Sci Rep 2018; 8:155. [PMID: 29317718 PMCID: PMC5760654 DOI: 10.1038/s41598-017-18547-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 12/13/2017] [Indexed: 01/08/2023] Open
Abstract
Protein phosphorylation plays a key role in Mycobacterium tuberculosis (Mtb) physiology and pathogenesis. We have previously shown that a secreted protein tyrosine phosphatase, PtpA, is essential for Mtb inhibition of host macrophage acidification and maturation, and is a substrate of the protein tyrosine kinase, PtkA, encoded in the same operon. In this study, we constructed a ∆ptkA deletion mutant in Mtb and found that the mutant exhibited impaired intracellular survival in the THP-1 macrophage infection model, correlated with the strain's inability to inhibit macrophage phagosome acidification. By contrast, the mutant displayed increased resistance to oxidative stress in vitro. Proteomic and transcriptional analyses revealed upregulation of ptpA, and increased secretion of TrxB2, in the ΔptkA mutant. Kinase and protein-protein interaction studies demonstrated that TrxB2 is a substrate of PtkA phosphorylation. Taken together these studies establish a central role for the ptkA-ptpA operon in Mtb pathogenesis.
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12
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de Oliveira Viana J, Scotti MT, Scotti L. Molecular Docking Studies in Multitarget Antitubercular Drug Discovery. METHODS IN PHARMACOLOGY AND TOXICOLOGY 2018. [DOI: 10.1007/7653_2018_28] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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13
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Bertoldo JB, Rodrigues T, Dunsmore L, Aprile FA, Marques MC, Rosado LA, Boutureira O, Steinbrecher TB, Sherman W, Corzana F, Terenzi H, Bernardes GJL. A Water-Bridged Cysteine-Cysteine Redox Regulation Mechanism in Bacterial Protein Tyrosine Phosphatases. Chem 2017; 3:665-677. [PMID: 29094109 PMCID: PMC5656095 DOI: 10.1016/j.chempr.2017.07.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 06/01/2017] [Accepted: 07/07/2017] [Indexed: 11/25/2022]
Abstract
The emergence of multidrug-resistant Mycobacterium tuberculosis (Mtb) strains highlights the need to develop more efficacious and potent drugs. However, this goal is dependent on a comprehensive understanding of Mtb virulence protein effectors at the molecular level. Here, we used a post-expression cysteine (Cys)-to-dehydrolanine (Dha) chemical editing strategy to identify a water-mediated motif that modulates accessibility of the protein tyrosine phosphatase A (PtpA) catalytic pocket. Importantly, this water-mediated Cys-Cys non-covalent motif is also present in the phosphatase SptpA from Staphylococcus aureus, which suggests a potentially preserved structural feature among bacterial tyrosine phosphatases. The identification of this structural water provides insight into the known resistance of Mtb PtpA to the oxidative conditions that prevail within an infected host macrophage. This strategy could be applied to extend the understanding of the dynamics and function(s) of proteins in their native state and ultimately aid in the design of small-molecule modulators.
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Affiliation(s)
- Jean B Bertoldo
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.,Centro de Biologia Molecular Estrutural, Departamento de Bioquímica, Universidade Federal de Santa Catarina, 88040-970 Florianópolis-SC, Brazil
| | - Tiago Rodrigues
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028 Lisbon, Portugal
| | - Lavinia Dunsmore
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
| | - Francesco A Aprile
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
| | - Marta C Marques
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028 Lisbon, Portugal
| | - Leonardo A Rosado
- Centro de Biologia Molecular Estrutural, Departamento de Bioquímica, Universidade Federal de Santa Catarina, 88040-970 Florianópolis-SC, Brazil
| | - Omar Boutureira
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
| | | | - Woody Sherman
- Schrödinger, 120 West 45th Street, New York, NY 10036, USA
| | - Francisco Corzana
- Departamento de Química, Universidad de La Rioja, Centro de Investigación en Síntesis Química, 26006 Logroño, Spain
| | - Hernán Terenzi
- Centro de Biologia Molecular Estrutural, Departamento de Bioquímica, Universidade Federal de Santa Catarina, 88040-970 Florianópolis-SC, Brazil
| | - Gonçalo J L Bernardes
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.,Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Avenida Professor Egas Moniz, 1649-028 Lisbon, Portugal
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14
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Wang J, Ge P, Qiang L, Tian F, Zhao D, Chai Q, Zhu M, Zhou R, Meng G, Iwakura Y, Gao GF, Liu CH. The mycobacterial phosphatase PtpA regulates the expression of host genes and promotes cell proliferation. Nat Commun 2017; 8:244. [PMID: 28811474 PMCID: PMC5557760 DOI: 10.1038/s41467-017-00279-z] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 06/16/2017] [Indexed: 01/05/2023] Open
Abstract
Mycobacterium tuberculosis PtpA is a secreted effector protein that dephosphorylates several proteins in the host cell cytoplasm, such as p-JNK, p-p38, and p-VPS33B, leading to suppression of host innate immunity. Here we show that, in addition, PtpA enters the nucleus of host cells and regulates the expression of host genes, some of which are known to be involved in host innate immunity or in cell proliferation and migration (such as GADD45A). PtpA can bind directly to the promoter region of GADD45A in vitro. Both phosphatase activity and DNA-binding ability of PtpA are important in suppressing host innate immune responses. Furthermore, PtpA-expressing Mycobacterium bovis BCG promotes proliferation and migration of human lung adenoma A549 cells in vitro and in a mouse xenograft model. Further research is needed to test whether mycobacteria, via PtpA, might affect cell proliferation or migration in humans. Mycobacterium tuberculosis secretes a protein, PtpA, that dephosphorylates proteins in the host cell cytoplasm, weakening immune responses. Here, the authors show that PtpA also enters the nucleus, affects the expression of several host genes, and promotes proliferation and migration of a cancer cell line.
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Affiliation(s)
- Jing Wang
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Pupu Ge
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.,Savaid Medical School, University of Chinese Academy of Sciences, Beijing, 101408, China
| | - Lihua Qiang
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.,Institute of Health Sciences, Anhui University, Hefei, 230601, China
| | - Feng Tian
- Center for Bioinformatics, Peking University, Beijing, 100871, China
| | - Dongdong Zhao
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.,Savaid Medical School, University of Chinese Academy of Sciences, Beijing, 101408, China
| | - Qiyao Chai
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.,Savaid Medical School, University of Chinese Academy of Sciences, Beijing, 101408, China
| | - Mingzhao Zhu
- CAS Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Rongbin Zhou
- Institute of Immunology and the CAS Key Laboratory of Innate Immunity and Chronic Disease, Chinese Academy of Sciences Center for Excellence in Molecular Cell Sciences, School of Life Sciences and Medical Center, University of Science and Technology of China, Hefei, 230027, China
| | - Guangxun Meng
- CAS Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Yoichiro Iwakura
- Division of Experimental Animal Immunology, Center for Animal Disease Models, Research Institute for Biomedical Sciences, Tokyo University of Science, Chiba, 278-0022, Japan
| | - George Fu Gao
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.,Savaid Medical School, University of Chinese Academy of Sciences, Beijing, 101408, China
| | - Cui Hua Liu
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China. .,Savaid Medical School, University of Chinese Academy of Sciences, Beijing, 101408, China.
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15
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Ku B, Keum CW, Lee HS, Yun HY, Shin HC, Kim BY, Kim SJ. Crystal structure of SP-PTP, a low molecular weight protein tyrosine phosphatase from Streptococcus pyogenes. Biochem Biophys Res Commun 2016; 478:1217-22. [PMID: 27545603 DOI: 10.1016/j.bbrc.2016.08.097] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 08/17/2016] [Indexed: 11/25/2022]
Abstract
Streptococcus pyogenes, or Group A Streptococcus (GAS), is a pathogenic bacterium that causes a variety of infectious diseases. The GAS genome encodes one protein tyrosine phosphatase, SP-PTP, which plays an essential role in the replication and virulence maintenance of GAS. Herein, we present the crystal structure of SP-PTP at 1.9 Å resolution. Although SP-PTP has been reported to have dual phosphatase specificity for both phosphorylated tyrosine and serine/threonine, three-dimensional structural analysis showed that SP-PTP shares high similarity with typical low molecular weight protein tyrosine phosphatases (LMWPTPs), which are specific for phosphotyrosine, but not with dual-specificity phosphatases, in overall folding and active site composition. In the dephosphorylation activity test, SP-PTP consistently acted on phosphotyrosine substrates, but not or only minimally on phosphoserine/phosphothreonine substrates. Collectively, our structural and biochemical analyses verified SP-PTP as a canonical tyrosine-specific LMWPTP.
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Affiliation(s)
- Bonsu Ku
- Disease Target Structure Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea; Department of Bio-Analytical Science, University of Science and Technology, Daejeon, Republic of Korea.
| | - Chae Won Keum
- Disease Target Structure Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea; Department of Bio-Analytical Science, University of Science and Technology, Daejeon, Republic of Korea
| | - Hye Seon Lee
- Disease Target Structure Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea; Department of Biology, Chungnam National University, Daejeon, Republic of Korea
| | - Hye-Yeoung Yun
- Disease Target Structure Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea; Department of Bio-Analytical Science, University of Science and Technology, Daejeon, Republic of Korea
| | - Ho-Chul Shin
- Disease Target Structure Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
| | - Bo Yeon Kim
- Incurable Diseases Therapeutics Research Center, World Class Institute, Korea Research Institute of Bioscience and Biotechnology, Ochang, Cheongwon, Republic of Korea
| | - Seung Jun Kim
- Disease Target Structure Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea; Department of Bio-Analytical Science, University of Science and Technology, Daejeon, Republic of Korea.
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16
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Dutta NK, He R, Pinn ML, He Y, Burrows F, Zhang ZY, Karakousis PC. Mycobacterial Protein Tyrosine Phosphatases A and B Inhibitors Augment the Bactericidal Activity of the Standard Anti-tuberculosis Regimen. ACS Infect Dis 2016; 2:231-239. [PMID: 27478867 DOI: 10.1021/acsinfecdis.5b00133] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Novel drugs are required to shorten the duration of treatment for tuberculosis (TB) and to combat the emergence of drug resistance. One approach has been to identify and target Mycobacterium tuberculosis (Mtb) virulence factors, which promote the establishment of TB infection and pathogenesis. Mtb produces a number of virulence factors, including two protein tyrosine phosphatases (PTPs), mPTPA and mPTPB, to evade the antimicrobial functions of host macrophages. To assess the therapeutic potential of targeting the virulent Mtb PTPs, we developed highly potent and selective inhibitors of mPTPA (L335-M34) and mPTPB (L01-Z08) with drug-like properties. We tested the bactericidal activity of L335-M34 and L01-Z08 alone or together in combination with the standard antitubercular regimen of isoniazid-rifampicin-pyrazinamide (HRZ) in the guinea pig model of chronic TB infection, which faithfully recapitulates some of the key histological features of human TB lesions. Following a single dose of L335-M34 50mg/kg and L01-Z08 20 mg/kg, plasma levels were maintained at levels 10-fold greater than the biochemical IC50 for 12-24 hours. Although neither PTP inhibitor alone significantly enhanced the antibacterial activity of HRZ, dual inhibition of mPTPA and mPTPB in combination with HRZ showed modest synergy, even after 2 weeks of treatment. After 6 weeks of treatment, the degree of lung inflammation correlated with the bactericidal activity of each drug regimen. This study highlights the potential utility of targeting Mtb virulence factors, and specifically the Mtb PTPs, as a strategy for enhancing the activity of standard anti-TB treatment.
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Affiliation(s)
- Noton K. Dutta
- Center for Tuberculosis
Research, Department of Medicine, Johns Hopkins University School of Medicine, 1551 East Jefferson Street, Baltimore, Maryland 21287, United States
| | - Rongjun He
- Department of Biochemistry and Molecular
Biology Indiana University School of Medicine, 635 Barnhill Drive, MS 4053, Indianapolis, Indiana 46202, United States
| | - Michael L. Pinn
- Center for Tuberculosis
Research, Department of Medicine, Johns Hopkins University School of Medicine, 1551 East Jefferson Street, Baltimore, Maryland 21287, United States
| | - Yantao He
- Department of Biochemistry and Molecular
Biology Indiana University School of Medicine, 635 Barnhill Drive, MS 4053, Indianapolis, Indiana 46202, United States
| | - Francis Burrows
- Aarden Pharmaceuticals, Inc., 351 West 10th Street, Suite 248, Indianapolis, Indiana 46202, United States
| | - Zhong-Yin Zhang
- Department of Biochemistry and Molecular
Biology Indiana University School of Medicine, 635 Barnhill Drive, MS 4053, Indianapolis, Indiana 46202, United States
| | - Petros C. Karakousis
- Center for Tuberculosis
Research, Department of Medicine, Johns Hopkins University School of Medicine, 1551 East Jefferson Street, Baltimore, Maryland 21287, United States
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, Maryland 21205, United States
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17
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Hmama Z, Peña-Díaz S, Joseph S, Av-Gay Y. Immunoevasion and immunosuppression of the macrophage by Mycobacterium tuberculosis. Immunol Rev 2015; 264:220-32. [PMID: 25703562 DOI: 10.1111/imr.12268] [Citation(s) in RCA: 195] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
By virtue of their position at the crossroads between the innate and adaptive immune response, macrophages play an essential role in the control of bacterial infections. Paradoxically, macrophages serve as the natural habitat to Mycobacterium tuberculosis (Mtb). Mtb subverts the macrophage's mechanisms of intracellular killing and antigen presentation, leading ultimately to the development of tuberculosis (TB) disease. Here, we describe mechanisms of Mtb uptake by the macrophage and address key macrophage functions that are targeted by Mtb-specific effector molecules enabling this pathogen to circumvent host immune response. The macrophage functions described in this review include fusion between phagosomes and lysosomes, production of reactive oxygen and nitrogen species, antigen presentation and major histocompatibility complex class II expression and trafficking, as well as autophagy and apoptosis. All these are Mtb-targeted key cellular pathways, normally working in concert in the macrophage to recognize, respond, and activate 'proper' immune responses. We further analyze and discuss major molecular interactions between Mtb virulence factors and key macrophage proteins and provide implications for vaccine and drug development.
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Affiliation(s)
- Zakaria Hmama
- Department of Medicine, Division of Infectious Diseases, Infection and Immunity Research Center, University of British Columbia, Vancouver, BC, Canada
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18
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Sajid A, Arora G, Singhal A, Kalia VC, Singh Y. Protein Phosphatases of Pathogenic Bacteria: Role in Physiology and Virulence. Annu Rev Microbiol 2015; 69:527-47. [DOI: 10.1146/annurev-micro-020415-111342] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Andaleeb Sajid
- Institute of Genomics and Integrative Biology, Council of Scientific and Industrial Research, Delhi 110007, India;
| | - Gunjan Arora
- Institute of Genomics and Integrative Biology, Council of Scientific and Industrial Research, Delhi 110007, India;
| | - Anshika Singhal
- Institute of Genomics and Integrative Biology, Council of Scientific and Industrial Research, Delhi 110007, India;
| | - Vipin C. Kalia
- Institute of Genomics and Integrative Biology, Council of Scientific and Industrial Research, Delhi 110007, India;
| | - Yogendra Singh
- Institute of Genomics and Integrative Biology, Council of Scientific and Industrial Research, Delhi 110007, India;
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19
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Zhou P, Wong D, Li W, Xie J, Av-Gay Y. Phosphorylation of Mycobacterium tuberculosis protein tyrosine kinase A PtkA by Ser/Thr protein kinases. Biochem Biophys Res Commun 2015; 467:421-6. [PMID: 26417687 DOI: 10.1016/j.bbrc.2015.09.124] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 09/22/2015] [Indexed: 12/01/2022]
Abstract
Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), has inflicted about one third of mankind and claims millions of deaths worldwide annually. Signalling plays an important role in Mtb pathogenesis and persistence, and thus represents attractive resource for drug target candidates. Here, we show that protein tyrosine kinase A (PtkA) can be phosphorylated by Mtb endogenous eukaryotic-like Ser/Thr protein kinases (eSTPKs). Kinase assays showed that PknA, PknD, PknF, and PknK can phosphorylate PtkA in dose- and time-dependent manner. Enzyme kinetics suggests that PknA has the highest affinity and enzymatic efficiency towards PtkA. Furthermore, protein-protein interaction assay in surrogate host showed that PtkA interacts with multi-eSTPKs in vivo, including PknA. Lastly, we show that PtkA phosphorylation by eSTPKs occurs on threonine residues and may effect tyrosine phosphorylation levels and thus PtkA activity in vitro. These results demonstrate that PtkA can serve as a substrate to many eSTPKs and suggests that's its activity can be regulated.
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Affiliation(s)
- Peifu Zhou
- Department of Medicine, Division of Infectious Diseases, University of British Columbia, Vancouver, BC, V5Z 3J5, Canada; Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, School of Life Sciences, Southwest University, Chongqing, 400715, China; Institute of Ethnic-minority Medicine, School of Chemistry & Environmental Science, Guizhou Minzu University, Guiyang, 550025, China
| | - Dennis Wong
- Department of Medicine, Division of Infectious Diseases, University of British Columbia, Vancouver, BC, V5Z 3J5, Canada
| | - Wu Li
- Department of Medicine, Division of Infectious Diseases, University of British Columbia, Vancouver, BC, V5Z 3J5, Canada; Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Jianping Xie
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, School of Life Sciences, Southwest University, Chongqing, 400715, China.
| | - Yossef Av-Gay
- Department of Medicine, Division of Infectious Diseases, University of British Columbia, Vancouver, BC, V5Z 3J5, Canada.
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20
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Li J, Chai QY, Zhang Y, Li BX, Wang J, Qiu XB, Liu CH. Mycobacterium tuberculosis Mce3E suppresses host innate immune responses by targeting ERK1/2 signaling. THE JOURNAL OF IMMUNOLOGY 2015; 194:3756-67. [PMID: 25780035 DOI: 10.4049/jimmunol.1402679] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 02/12/2015] [Indexed: 11/19/2022]
Abstract
Crucial to the pathogenesis of the tuberculosis (TB)-causing pathogen Mycobacterium tuberculosis is its ability to subvert host immune defenses to promote its intracellular survival. The mammalian cell entry protein 3E (Mce3E), located in the region of difference 15 of the M. tuberculosis genome and absent in Mycobacterium bovis bacillus Calmette-Guérin, has an essential role in facilitating the internalization of mammalian cells by mycobacteria. However, relatively little is known about the role of Mce3E in modulation of host innate immune responses. In this study, we demonstrate that Mce3E inhibits the activation of the ERK1/2 signaling pathway, leading to the suppression of Tnf and Il6 expression, and the promotion of mycobacterial survival within macrophages. Mce3E interacts and colocalizes with ERK1/2 at the endoplasmic reticulum in a DEF motif (an ERK-docking motif)-dependent manner, relocates ERK1/2 from cytoplasm to the endoplasmic reticulum, and finally reduces the association of ERK1/2 with MEK1 and blocks the nuclear translocation of phospho-ERK1/2. A DEF motif mutant form of Mce3E (F294A) loses its ability to suppress Tnf and Il6 expression and to promote intracellular survival of mycobacteria. Inhibition of the ERK1/2 pathway in macrophages using U0126, a specific inhibitor of the ERK pathway, also leads to the suppressed Tnf and Il6 expression and the enhanced intracellular survival of mycobacteria. Taken together, these results suggest that M. tuberculosis Mce3E exploits the ERK1/2 signaling pathway to suppress host innate immune responses, providing a potential Mce3E-ERK1/2 interface-based drug target against M. tuberculosis.
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Affiliation(s)
- Jie Li
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; and
| | - Qi-Yao Chai
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; and
| | - Yong Zhang
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; and
| | - Bing-Xi Li
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; and
| | - Jing Wang
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; and
| | - Xiao-Bo Qiu
- Department of Cell Biology, Ministry of Education Key Laboratory of Cell Proliferation and Regulation Biology, College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Cui Hua Liu
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; and
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21
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New potential eukaryotic substrates of the mycobacterial protein tyrosine phosphatase PtpA: hints of a bacterial modulation of macrophage bioenergetics state. Sci Rep 2015; 5:8819. [PMID: 25743628 PMCID: PMC5390082 DOI: 10.1038/srep08819] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 01/27/2015] [Indexed: 11/16/2022] Open
Abstract
The bacterial protein tyrosine phosphatase PtpA is a key virulence factor released by Mycobacterium tuberculosis in the cytosol of infected macrophages. So far only two unrelated macrophage components (VPS33B, GSK3α) have been identified as PtpA substrates. As tyrosine phosphatases are capable of using multiple substrates, we developed an improved methodology to pull down novel PtpA substrates from an enriched P-Y macrophage extract using the mutant PtpA D126A. This methodology reduced non-specific protein interactions allowing the identification of four novel putative PtpA substrates by MALDI-TOF-MS and nano LC-MS: three mitochondrial proteins - the trifunctional enzyme (TFP), the ATP synthase, and the sulfide quinone oxidoreductase - and the cytosolic 6-phosphofructokinase. All these proteins play a relevant role in cell energy metabolism. Using surface plasmon resonance, PtpA was found to bind immunopurified human TFP through its catalytic site since TFP-PtpA association was inhibited by a specific phosphatase inhibitor. Moreover, PtpA wt was capable of dephosphorylating immunopurified human TFP in vitro supporting that TFP may be a bona fide PtpA susbtrate. Overall, these results suggest a novel scenario where PtpA-mediated dephosphorylation may affect pathways involved in cell energy metabolism, particularly the beta oxidation of fatty acids through modulation of TFP activity and/or cell distribution.
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22
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Mycobacterium tuberculosis suppresses innate immunity by coopting the host ubiquitin system. Nat Immunol 2015; 16:237-45. [DOI: 10.1038/ni.3096] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 01/02/2015] [Indexed: 12/13/2022]
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23
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Zhou P, Li W, Wong D, Xie J, Av-Gay Y. Phosphorylation control of protein tyrosine phosphatase A activity in Mycobacterium tuberculosis. FEBS Lett 2014; 589:326-31. [PMID: 25535696 DOI: 10.1016/j.febslet.2014.12.015] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 12/07/2014] [Accepted: 12/09/2014] [Indexed: 11/25/2022]
Abstract
Protein tyrosine phosphatase A (PtpA) has been shown to play a key role in human macrophage infection by Mycobacterium tuberculosis (Mtb). Protein tyrosine kinase A (PtkA) was the first protein tyrosine kinase shown to phosphorylate PtpA. Here, we found that PtkA-mediated phosphorylation of PtPA on Tyr-128 and Tyr-129 enhances the PtPA phosphatase activity. Moreover, ex-vivo protein-protein interaction assays showed that PtpA can be phosphorylated by several eukaryotic-like Ser/Thr protein kinases, such as protein kinase A (PknA). PknA was found to regulate PtpA phosphatase activity through Thr-45 phosphorylation. These results indicate that members of two independent families of protein kinases tune PtpA activity in Mtb.
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Affiliation(s)
- Peifu Zhou
- Department of Medicine, Division of Infectious Diseases, University of British Columbia, Vancouver, BC V5Z 3J5, Canada; Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-environment and Bio-resource of the Three Gorges Area, Key Laboratory of Eco-environment of Three Gorges Reservoir, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China; Institute of Ethnic-minority Medicine, School of Chemistry & Environmental Science, Guizhou Minzu University, Guiyang 550025, China
| | - Wu Li
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-environment and Bio-resource of the Three Gorges Area, Key Laboratory of Eco-environment of Three Gorges Reservoir, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China
| | - Dennis Wong
- Department of Medicine, Division of Infectious Diseases, University of British Columbia, Vancouver, BC V5Z 3J5, Canada
| | - Jianping Xie
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-environment and Bio-resource of the Three Gorges Area, Key Laboratory of Eco-environment of Three Gorges Reservoir, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400715, China.
| | - Yossef Av-Gay
- Department of Medicine, Division of Infectious Diseases, University of British Columbia, Vancouver, BC V5Z 3J5, Canada.
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24
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Andrade A, Valvano MA. A Burkholderia cenocepacia gene encoding a non-functional tyrosine phosphatase is required for the delayed maturation of the bacteria-containing vacuoles in macrophages. Microbiology (Reading) 2014; 160:1332-1345. [DOI: 10.1099/mic.0.077206-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Burkholderia cenocepacia infects patients with cystic fibrosis. We have previously shown that B. cenocepacia can survive in macrophages within membrane vacuoles [B. cenocepacia-containing vacuoles (BcCVs)] that preclude fusion with the lysosome. The bacterial factors involved in B. cenocepacia intracellular survival are not fully elucidated. We report here that deletion of BCAM0628, encoding a predicted low molecular weight protein tyrosine phosphatase (LMW-PTP) that is restricted to B. cenocepacia strains of the transmissible ET-12 clone, accelerates the maturation of the BcCVs. Compared to the parental strain and deletion mutants in other LMW-PTPs that are widely conserved in Burkholderia species, a greater proportion of BcCVs containing the ΔBCAM0628 mutant were targeted to the lysosome. Accelerated BcCV maturation was not due to reduced intracellular viability since ΔBCAM0628 survived and replicated in macrophages similarly to the parental strain. Therefore, BCAM0628 was referred to as dpm (delayed phagosome maturation). We provide evidence that the Dpm protein is secreted during growth in vitro and upon macrophage infection. Dpm secretion requires an N-terminal signal peptide. Heterologous expression of Dpm in Burkholderia multivorans confers to this bacterium a similar phagosomal maturation delay to that found with B. cenocepacia. We demonstrate that Dpm is an inactive phosphatase, suggesting that its contribution to phagosomal maturation arrest must be unrelated to tyrosine phosphatase activity.
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Affiliation(s)
- Angel Andrade
- Centre for Human Immunology and Department of Microbiology and Immunology, University of Western Ontario, London, ON N6A 5C1, Canada
| | - Miguel A. Valvano
- Centre for Infection and Immunity, Queen's University Belfast, Belfast BT9 5AE, UK
- Centre for Human Immunology and Department of Microbiology and Immunology, University of Western Ontario, London, ON N6A 5C1, Canada
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25
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Mori Y, Kimura Y. Myxococcus xanthus low-molecular-weight protein tyrosine phosphatase homolog, ArsA, possesses arsenate reductase activity. J Biosci Bioeng 2014; 118:10-3. [PMID: 24503422 DOI: 10.1016/j.jbiosc.2013.12.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 12/13/2013] [Accepted: 12/18/2013] [Indexed: 11/25/2022]
Abstract
Myxococcus xanthus MXAN_0575, ArsA, exhibited sequence homology to low-molecular-weight protein tyrosine phosphatases (LMWPTPs) and arsenate reductases. ArsA exhibited weak phosphatase activity toward p-nitrophenyl phosphate, and high arsenate reductase activity, suggesting that ArsA may play a role in arsenate reductase, but not LMWPTP.
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Affiliation(s)
- Yumi Mori
- Department of Applied Biological Science, Faculty of Agriculture, Kagawa University, Miki-cho, Kagawa 761-0795, Japan
| | - Yoshio Kimura
- Department of Applied Biological Science, Faculty of Agriculture, Kagawa University, Miki-cho, Kagawa 761-0795, Japan.
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26
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Coker OO, Warit S, Rukseree K, Summpunn P, Prammananan T, Palittapongarnpim P. Functional characterization of two members of histidine phosphatase superfamily in Mycobacterium tuberculosis. BMC Microbiol 2013; 13:292. [PMID: 24330471 PMCID: PMC3866925 DOI: 10.1186/1471-2180-13-292] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 12/07/2013] [Indexed: 01/19/2023] Open
Abstract
Background Functional characterization of genes in important pathogenic bacteria such as Mycobacterium tuberculosis is imperative. Rv2135c, which was originally annotated as conserved hypothetical, has been found to be associated with membrane protein fractions of H37Rv strain. The gene appears to contain histidine phosphatase motif common to both cofactor-dependent phosphoglycerate mutases and acid phosphatases in the histidine phosphatase superfamily. The functions of many of the members of this superfamily are annotated based only on similarity to known proteins using automatic annotation systems, which can be erroneous. In addition, the motif at the N-terminal of Rv2135c is ‘RHA’ unlike ‘RHG’ found in most members of histidine phosphatase superfamily. These necessitate the need for its experimental characterization. The crystal structure of Rv0489, another member of the histidine phosphatase superfamily in M. tuberculosis, has been previously reported. However, its biochemical characteristics remain unknown. In this study, Rv2135c and Rv0489 from M. tuberculosis were cloned and expressed in Escherichia coli with 6 histidine residues tagged at the C terminal. Results Characterization of the purified recombinant proteins revealed that Rv0489 possesses phosphoglycerate mutase activity while Rv2135c does not. However Rv2135c has an acid phosphatase activity with optimal pH of 5.8. Kinetic parameters of Rv2135c and Rv0489 are studied, confirming that Rv0489 is a cofactor dependent phosphoglycerate mutase of M. tuberculosis. Additional characterization showed that Rv2135c exists as a tetramer while Rv0489 as a dimer in solution. Conclusion Most of the proteins orthologous to Rv2135c in other bacteria are annotated as phosphoglycerate mutases or hypothetical proteins. It is possible that they are actually phosphatases. Experimental characterization of a sufficiently large number of bacterial histidine phosphatases will increase the accuracy of the automatic annotation systems towards a better understanding of this important group of enzymes.
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Affiliation(s)
| | | | | | | | | | - Prasit Palittapongarnpim
- Department of Microbiology, Faculty of Science, Mahidol University, Rama 6 Road, Bangkok 10400, Thailand.
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Wong D, Chao JD, Av-Gay Y. Mycobacterium tuberculosis-secreted phosphatases: from pathogenesis to targets for TB drug development. Trends Microbiol 2013; 21:100-9. [DOI: 10.1016/j.tim.2012.09.002] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Revised: 09/10/2012] [Accepted: 09/14/2012] [Indexed: 01/02/2023]
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Forrellad MA, Klepp LI, Gioffré A, Sabio y García J, Morbidoni HR, de la Paz Santangelo M, Cataldi AA, Bigi F. Virulence factors of the Mycobacterium tuberculosis complex. Virulence 2012; 4:3-66. [PMID: 23076359 PMCID: PMC3544749 DOI: 10.4161/viru.22329] [Citation(s) in RCA: 368] [Impact Index Per Article: 30.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The Mycobacterium tuberculosis complex (MTBC) consists of closely related species that cause tuberculosis in both humans and animals. This illness, still today, remains to be one of the leading causes of morbidity and mortality throughout the world. The mycobacteria enter the host by air, and, once in the lungs, are phagocytated by macrophages. This may lead to the rapid elimination of the bacillus or to the triggering of an active tuberculosis infection. A large number of different virulence factors have evolved in MTBC members as a response to the host immune reaction. The aim of this review is to describe the bacterial genes/proteins that are essential for the virulence of MTBC species, and that have been demonstrated in an in vivo model of infection. Knowledge of MTBC virulence factors is essential for the development of new vaccines and drugs to help manage the disease toward an increasingly more tuberculosis-free world.
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Newton-Foot M, Gey van Pittius NC. The complex architecture of mycobacterial promoters. Tuberculosis (Edinb) 2012; 93:60-74. [PMID: 23017770 DOI: 10.1016/j.tube.2012.08.003] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Revised: 07/31/2012] [Accepted: 08/06/2012] [Indexed: 01/02/2023]
Abstract
The genus Mycobacterium includes a variety of species with differing phenotypic properties, including growth rate, pathogenicity and environment- and host-specificity. Although many mycobacterial species have been extensively studied and their genomes sequenced, the reasons for phenotypic variation between closely related species remain unclear. Variation in gene expression may contribute to these characteristics and enable the bacteria to respond to changing environmental conditions. Gene expression is controlled primarily at the level of transcription, where the main element of regulation is the promoter. Transcriptional regulation and associated promoter sequences have been studied extensively in E. coli. This review describes the complex structure and characteristics of mycobacterial promoters, in comparison to the classical E. coli prokaryotic promoter structure. Some components of mycobacterial promoters are similar to those of E. coli. These include the predominant guanine residue at the transcriptional start point, conserved -10 hexamer, similar interhexameric distances, the use of ATG as a start codon, the guanine- and adenine-rich ribosome binding site and the presence of extended -10 (TGn) motifs in strong promoters. However, these components are much more variable in sequence in mycobacterial promoters and no conserved -35 hexamer sequence (clearly defined in E. coli) can be identified. This may be a result of the high G+C content of mycobacterial genomes, as well as the large number of sigma factors present in mycobacteria, which may recognise different promoter sequences. Mycobacteria possess a complex transcriptional regulatory network. Numerous regulatory motifs have been identified in mycobacterial promoters, predominantly in the interhexameric region. These are bound by specific transcriptional regulators in response to environmental changes. The combination of specific promoter sequences, transcriptional regulators and a variety of sigma factors enables rapid and specific responses to diverse conditions and different stages of infection. This review aims to provide an overview of the complex architecture of mycobacterial transcriptional regulation.
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Affiliation(s)
- Mae Newton-Foot
- DST/NRF Centre of Excellence for Biomedical Tuberculosis Research/MRC Centre for Molecular and Cellular Biology, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, PO Box 19063, Francie van Zijl Drive, Tygerberg 7505, South Africa.
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Stehle T, Sreeramulu S, Löhr F, Richter C, Saxena K, Jonker HRA, Schwalbe H. The apo-structure of the low molecular weight protein-tyrosine phosphatase A (MptpA) from Mycobacterium tuberculosis allows for better target-specific drug development. J Biol Chem 2012; 287:34569-82. [PMID: 22888002 DOI: 10.1074/jbc.m112.399261] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Protein-tyrosine phosphatases (PTPs) and protein-tyrosine kinases co-regulate cellular processes. In pathogenic bacteria, they are frequently exploited to act as key virulence factors for human diseases. Mycobacterium tuberculosis, the causative organism of tuberculosis, secretes a low molecular weight PTP (LMW-PTP), MptpA, which is required for its survival upon infection of host macrophages. Although there is otherwise no sequence similarity of LMW-PTPs to other classes of PTPs, the phosphate binding loop (P-loop) CX(5)R and the loop containing a critical aspartic acid residue (D-loop), required for the catalytic activity, are well conserved. In most high molecular weight PTPs, ligand binding to the P-loop triggers a large conformational reorientation of the D-loop, in which it moves ∼10 Å, from an "open" to a "closed" conformation. Until now, there have been no ligand-free structures of LMW-PTPs described, and hence the dynamics of the D-loop have remained largely unknown for these PTPs. Here, we present a high resolution solution NMR structure of the free form of the MptpA LMW-PTP. In the absence of ligand and phosphate ions, the D-loop adopts an open conformation. Furthermore, we characterized the binding site of phosphate, a competitive inhibitor of LMW-PTPs, on MptpA and elucidated the involvement of both the P- and D-loop in phosphate binding. Notably, in LMW-PTPs, the phosphorylation status of two well conserved tyrosine residues, typically located in the D-loop, regulates the enzyme activity. PtkA, the kinase complementary to MptpA, phosphorylates these two tyrosine residues in MptpA. We characterized the MptpA-PtkA interaction by NMR spectroscopy to show that both the P- and D-loop form part of the binding interface.
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Affiliation(s)
- Tanja Stehle
- Institute for Organic Chemistry and Chemical Biology, ohann Wolfgang Goethe University, Max-von-Laue-Strasse 7, D-60438 Frankfurt am Main, Germany
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Poirier V, Av-Gay Y. Mycobacterium tuberculosis modulators of the macrophage's cellular events. Microbes Infect 2012; 14:1211-9. [PMID: 22841679 DOI: 10.1016/j.micinf.2012.07.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Revised: 07/03/2012] [Accepted: 07/04/2012] [Indexed: 10/28/2022]
Abstract
A number of mycobacterial macromolecules have been shown to target biological processes within host macrophages; however, the exact mechanism for the majority of these host-pathogen interactions is poorly understood. The following review summarizes current knowledge and expands on a subset of mycobacterial effectors for which a cognate substrate, cellular partner or signaling pathway have been experimentally identified within the human host.
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Affiliation(s)
- Valérie Poirier
- Division of Infectious Diseases, Department of Medicine, University of British Columbia, Vancouver, BC, Canada
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32
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Abstract
Protein phosphorylation on tyrosine has emerged as a key device in the control of numerous cellular functions in bacteria. In this article, we review the structure and function of bacterial tyrosine kinases and phosphatases. Phosphorylation is catalyzed by autophosphorylating adenosine triphosphate-dependent enzymes (bacterial tyrosine (BY) kinases) that are characterized by the presence of Walker motifs. The reverse reaction is catalyzed by three classes of enzymes: the eukaryotic-like phosphatases (PTPs) and dual-specific phosphatases; the low molecular weight protein-tyrosine phosphatases (LMW-PTPs); and the polymerase–histidinol phosphatases (PHP). Many BY kinases and tyrosine phosphatases can utilize host cell proteins as substrates, thereby contributing to bacterial pathogenicity. Bacterial tyrosine phosphorylation/dephosphorylation is also involved in biofilm formation and community development. The Porphyromonas gingivalis tyrosine phosphatase Ltp1 is involved in a restraint pathway that regulates heterotypic community development with Streptococcus gordonii. Ltp1 is upregulated by contact with S. gordonii and Ltp1 activity controls adhesin expression and levels of the interspecies signal AI-2.
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Chiaradia LD, Martins PGA, Cordeiro MNS, Guido RVC, Ecco G, Andricopulo AD, Yunes RA, Vernal J, Nunes RJ, Terenzi H. Synthesis, biological evaluation, and molecular modeling of chalcone derivatives as potent inhibitors of Mycobacterium tuberculosis protein tyrosine phosphatases (PtpA and PtpB). J Med Chem 2011; 55:390-402. [PMID: 22136336 DOI: 10.1021/jm2012062] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Tuberculosis (TB) is a major infectious disease caused by Mycobacterium tuberculosis (Mtb). According to the World Health Organization (WHO), about 1.8 million people die from TB and 10 million new cases are recorded each year. Recently, a new series of naphthylchalcones has been identified as inhibitors of Mtb protein tyrosine phosphatases (PTPs). In this work, 100 chalcones were designed, synthesized, and investigated for their inhibitory properties against MtbPtps. Structure-activity relationships (SAR) were developed, leading to the discovery of new potent inhibitors with IC(50) values in the low-micromolar range. Kinetic studies revealed competitive inhibition and high selectivity toward the Mtb enzymes. Molecular modeling investigations were carried out with the aim of revealing the most relevant structural requirements underlying the binding affinity and selectivity of this series of inhibitors as potential anti-TB drugs.
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Affiliation(s)
- Louise Domeneghini Chiaradia
- Centro de Biologia Molecular Estrutural, CEBIME-UFSC, Universidade Federal de Santa Catarina, Campus Trindade, 88040-900 Florianópolis-SC, Brasil
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Mycobacterium tuberculosis protein tyrosine phosphatase (PtpA) excludes host vacuolar-H+-ATPase to inhibit phagosome acidification. Proc Natl Acad Sci U S A 2011; 108:19371-6. [PMID: 22087003 DOI: 10.1073/pnas.1109201108] [Citation(s) in RCA: 274] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb) pathogenicity depends on its ability to inhibit phagosome acidification and maturation processes after engulfment by macrophages. Here, we show that the secreted Mtb protein tyrosine phosphatase (PtpA) binds to subunit H of the macrophage vacuolar-H(+)-ATPase (V-ATPase) machinery, a multisubunit protein complex in the phagosome membrane that drives luminal acidification. Furthermore, we show that the macrophage class C vacuolar protein sorting complex, a key regulator of endosomal membrane fusion, associates with V-ATPase in phagosome maturation, suggesting a unique role for V-ATPase in coordinating phagosome-lysosome fusion. PtpA interaction with host V-ATPase is required for the previously reported dephosphorylation of VPS33B and subsequent exclusion of V-ATPase from the phagosome during Mtb infection. These findings show that inhibition of phagosome acidification in the mycobacterial phagosome is directly attributed to PtpA, a key protein needed for Mtb survival and pathogenicity within host macrophages.
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Li W, Xie J. Role of mycobacteria effectors in phagosome maturation blockage and new drug targets discovery. J Cell Biochem 2011; 112:2688-93. [DOI: 10.1002/jcb.23218] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Design, synthesis and inhibition activity of a novel cyclic enediyne amino acid conjugates against MPtpA. Bioorg Med Chem 2011; 19:3274-9. [PMID: 21530278 DOI: 10.1016/j.bmc.2011.03.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Revised: 03/09/2011] [Accepted: 03/10/2011] [Indexed: 12/23/2022]
Abstract
In course of studies towards the discovery of selective inhibitors of MPtpA, a novel cyclic endiyne malonamic acid has been designed and synthesized. The synthesis involves a crucial intramolecular Knoevenagel reaction. The compound displayed a reversible non-competitive inhibition against MPtpA with inhibition constant K(i) of 22.5 μM. The enediyne acts as a recognition framework in inducing the inhibition and not as a reactive functional moiety. This was confirmed by comparing the inhibiting activity with that of the corresponding saturated cyclic non-enediyne analogue.
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37
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Chandra K, Dutta D, Das AK, Basak A. Design, synthesis and inhibition activity of novel cyclic peptides against protein tyrosine phosphatase A from Mycobacterium tuberculosis. Bioorg Med Chem 2010; 18:8365-73. [DOI: 10.1016/j.bmc.2010.09.052] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Revised: 09/21/2010] [Accepted: 09/22/2010] [Indexed: 10/19/2022]
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Ashforth EJ, Fu C, Liu X, Dai H, Song F, Guo H, Zhang L. Bioprospecting for antituberculosis leads from microbial metabolites. Nat Prod Rep 2010; 27:1709-19. [PMID: 20922218 DOI: 10.1039/c0np00008f] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Elizabeth Jane Ashforth
- Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
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Fragment-based discovery of selective inhibitors of the Mycobacterium tuberculosis protein tyrosine phosphatase PtpA. Bioorg Med Chem Lett 2009; 19:6851-4. [PMID: 19889539 DOI: 10.1016/j.bmcl.2009.10.090] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2009] [Revised: 10/20/2009] [Accepted: 10/21/2009] [Indexed: 11/23/2022]
Abstract
The development of low muM inhibitors of the Mycobacterium tuberculosis phosphatase PtpA is reported. The most potent of these inhibitors (K(i)=1.4+/-0.3 microM) was found to be selective when tested against a panel of human tyrosine and dual-specificity phosphatases (11-fold vs the highly homologous HCPtpA, and >70-fold vs all others tested). Modeling the inhibitor-PtpA complexes explained the structure-activity relationships observed in vitro and revealed further possibilities for compound development.
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Chao J, Wong D, Zheng X, Poirier V, Bach H, Hmama Z, Av-Gay Y. Protein kinase and phosphatase signaling in Mycobacterium tuberculosis physiology and pathogenesis. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2009; 1804:620-7. [PMID: 19766738 DOI: 10.1016/j.bbapap.2009.09.008] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2009] [Revised: 09/06/2009] [Accepted: 09/10/2009] [Indexed: 01/22/2023]
Abstract
Mycobacterium tuberculosis (Mtb), the etiological agent of tuberculosis (TB), evades the antimicrobial defenses of the host and survives within the infected individual through a complex set of strategies. These include active prevention of host cellular killing processes as well as overwhelming adaptive gene expression. In the past decade, we have gained an increased understanding of how mycobacteria not only have the ability to adapt to a changing host environment but also actively interfere with the signaling machinery within the host cell to counteract or inhibit parts of the killing apparatus employed by the macrophage. Mtb is able to sense its environment via a set of phospho-signaling proteins which mediate its response and interaction with the host in a coordinated manner. In this review, we summarize the current knowledge about selected Mtb serine, threonine, and tyrosine kinase and phosphatase signaling proteins, focusing on the protein kinases, PknG and PtkA, and the protein phosphatase, PtpA.
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Affiliation(s)
- Joseph Chao
- Department of Microbiology, University of British Columbia, Vancouver, British Columbia, Canada V5Z 3J5
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41
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Mukherjee S, Dhar R, Das AK. Analyzing the catalytic mechanism of protein tyrosine phosphatase PtpB from Staphylococcus aureus through site-directed mutagenesis. Int J Biol Macromol 2009; 45:463-9. [PMID: 19747503 DOI: 10.1016/j.ijbiomac.2009.09.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2009] [Revised: 08/30/2009] [Accepted: 09/02/2009] [Indexed: 11/30/2022]
Abstract
Protein tyrosine phosphatase B (PtpB) from Staphylococcus aureus, MRSA 252, is a low molecular weight protein tyrosine phosphatase involved in its pathogenicity. PtpB has been modeled in silico and site-directed mutagenesis performed to ascertain the importance of active site residues Cys8, Arg14, Ser15 and Asp120 in its catalytic mechanism. Kinetic characterization of wild-type and the mutant PtpBs, C8S, R14A, S15T, S15A, D120A, D120E, D120N revealed the reaction mechanism followed by this LMWPTPase. The mutations caused major changes in the local environment resulting in significant decrease of its catalytic activity. Inhibition kinetics for the wild-type enzyme was performed with maleimide and maleimidobutyric acid.
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Affiliation(s)
- Somnath Mukherjee
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India
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Attarian R, Bennie C, Bach H, Av-Gay Y. Glutathione disulfide and S-nitrosoglutathione detoxification byMycobacteriumtuberculosisthioredoxin system. FEBS Lett 2009; 583:3215-20. [DOI: 10.1016/j.febslet.2009.09.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2009] [Accepted: 09/01/2009] [Indexed: 10/20/2022]
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Grundner C, Cox JS, Alber T. Protein tyrosine phosphatase PtpA is not required for Mycobacterium tuberculosis growth in mice. FEMS Microbiol Lett 2008; 287:181-4. [PMID: 18752626 DOI: 10.1111/j.1574-6968.2008.01309.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb) alters the host response to infection by secreting protein factors. Mtb produces two secreted protein tyrosine phosphatases, PtpA and PtpB, which are thought to interfere with host signaling. Deletion of ptpA or ptpB attenuates bacterial growth in activated macrophages. To address the in vivo function of PtpA, we generated a genetic deletion mutant, DeltaptpA. The mutant was not defective when grown in vitro, consistent with the presumed role of PtpA in the host. The ptpA mutant, however, also showed no growth defect in a mouse infection model. The absence of a growth defect in mice suggests that the requirement for PtpA differs in mouse and human infections, and that mice are not a suitable infection model for the study of PtpA.
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Affiliation(s)
- Christoph Grundner
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
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Mycobacterium tuberculosis virulence is mediated by PtpA dephosphorylation of human vacuolar protein sorting 33B. Cell Host Microbe 2008; 3:316-22. [PMID: 18474358 DOI: 10.1016/j.chom.2008.03.008] [Citation(s) in RCA: 217] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2007] [Revised: 02/06/2008] [Accepted: 03/14/2008] [Indexed: 01/08/2023]
Abstract
Entry into host macrophages and evasion of intracellular destruction mechanisms, including phagosome-lysosome fusion, are critical elements of Mycobacterium tuberculosis (Mtb) pathogenesis. To achieve this, the Mtb genome encodes several proteins that modify host signaling pathways. PtpA, a low-molecular weight tyrosine phosphatase, is a secreted Mtb protein of unknown function. The lack of tyrosine kinases in the Mtb genome suggests that PtpA may modulate host tyrosine phosphorylated protein(s). We report that a genetic deletion of ptpA attenuates Mtb growth in human macrophages, and expression of PtpA-neutralizing antibodies simulated this effect. We identify VPS33B, a regulator of membrane fusion, as a PtpA substrate. VPS33B and PtpA colocalize in Mtb-infected human macrophages. PtpA secretion combined with active-phosphorylated VPS33B inhibited phagosome-lysosome fusion, a process arrested in Mtb infections. These results demonstrate that PtpA is essential for Mtb intracellular persistence and identify a key host regulatory pathway that is inactivated by Mtb.
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45
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Responses of Mycobacterium tuberculosis hemoglobin promoters to in vitro and in vivo growth conditions. Appl Environ Microbiol 2008; 74:3512-22. [PMID: 18390674 DOI: 10.1128/aem.02663-07] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The success of Mycobacterium tuberculosis as one of the dreaded human pathogens lies in its ability to utilize different defense mechanisms in response to the varied environmental challenges during the course of its intracellular infection, latency, and reactivation cycle. Truncated hemoglobins trHbN and trHbO are thought to play pivotal roles in the cellular metabolism of this organism during stress and hypoxia. To delineate the genetic regulation of the M. tuberculosis hemoglobins, transcriptional fusions of the promoters of the glbN and glbO genes with green fluorescent protein were constructed, and their responses were monitored in Mycobacterium smegmatis and M. tuberculosis H37Ra exposed to environmental stresses in vitro and in M. tuberculosis H37Ra after in vivo growth inside macrophages. The glbN promoter activity increased substantially during stationary phase and was nearly 3- to 3.5-fold higher than the activity of the glbO promoter, which remained more or less constant during different growth phases in M. smegmatis, as well as in M. tuberculosis H37Ra. In both mycobacterial hosts, the glbN promoter activity was induced 1.5- to 2-fold by the general nitrosative stress inducer, nitrite, as well as the NO releaser, sodium nitroprusside (SNP). The glbO promoter was more responsive to nitrite than to SNP, although the overall increase in its activity was much less than that of the glbN promoter. Additionally, the glbN promoter remained insensitive to the oxidative stress generated by H(2)O(2), but the glbO promoter activity increased nearly 1.5-fold under similar conditions, suggesting that the trHb gene promoters are regulated differently under nitrosative and oxidative stress conditions. In contrast, transition metal-induced hypoxia enhanced the activity of both the glbN and glbO promoters at all growth phases; the glbO promoter was induced approximately 2.3-fold, which was found to be the highest value for this promoter under all the conditions evaluated. Addition of iron along with nickel reversed the induction in both cases. Interestingly, a concentration-dependent decrease in the activity of both trHb gene promoters was observed when the levels of iron in the growth media were depleted by addition of an iron chelator. These results suggested that an iron/heme-containing oxygen sensor is involved in the modulation of the trHb gene promoter activities directly or indirectly in conjunction with other cellular factors. The modes of promoter regulation under different physiological conditions were found to be similar for the trHbs in both M. smegmatis and M. tuberculosis H37Ra, indicating that the promoters might be regulated by components that are common to the two systems. Confocal microscopy of THP-1 macrophages infected with M. tuberculosis carrying the trHb gene promoter fusions showed that there was a significant level of promoter activity during intracellular growth in macrophages. Time course evaluation of the promoter activity after various times up to 48 h by fluorescence-activated cell sorting analysis of the intracellular M. tuberculosis cells indicated that the glbN promoter was active at all time points assessed, whereas the activity of the glbO promoter remained at a steady-state level up to 24 h postinfection and increased approximately 2-fold after 48 h of infection. Thus, the overall regulation pattern of the M. tuberculosis trHb gene promoters correlates not only with the stresses that the tubercle bacillus is likely to encounter once it is in the macrophage environment but also with our current knowledge of their functions. The in vivo studies that demonstrated for the first time expression of trHbs during macrophage infection of M. tuberculosis strongly indicate that the hemoglobins are required, and thus important, during the intracellular phase of the bacterial cycle. The present study of transcriptional regulation of M. tuberculosis hemoglobins in vitro under various stress conditions and in vivo after macrophage infection supports the hypothesis that biosynthesis of both trHbs (trHbN and trHbO) in the native host is regulated via the environmental signals that the tubercle bacillus receives during macrophage infection and growth in its human host.
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Madhurantakam C, Chavali VRM, Das AK. Analyzing the catalytic mechanism of MPtpA: A low molecular weight protein tyrosine phosphatase fromMycobacterium tuberculosis through site-directed mutagenesis. Proteins 2008; 71:706-14. [DOI: 10.1002/prot.21816] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Bach H, Sun J, Hmama Z, Av-Gay Y. Mycobacterium avium subsp. paratuberculosis PtpA is an endogenous tyrosine phosphatase secreted during infection. Infect Immun 2006; 74:6540-6. [PMID: 16982836 PMCID: PMC1698085 DOI: 10.1128/iai.01106-06] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Adaptive gene expression in prokaryotes is mediated by protein kinases and phosphatases. These regulatory proteins mediate phosphorylation of histidine or aspartate in two-component systems and serine/threonine or tyrosine in eukaryotic and eukaryote-like protein kinase systems. The genome sequence of Mycobacterium avium subsp. paratuberculosis, the causative agent of Johne's disease, does not possess a defined tyrosine kinase. Nevertheless, it encodes for protein tyrosine phosphatases. Here, we report that Map1985, is a functional low-molecular tyrosine phosphatase that is secreted intracellularly upon macrophage infection. This finding suggests that Map1985 might contribute to the pathogenesis of Mycobacterium avium subsp. paratuberculosis by dephosphorylating essential macrophage signaling and/or adaptor molecules.
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Affiliation(s)
- Horacio Bach
- Department of Medicine, Division of Infectious Diseases, University of British Columbia, 2733 Heather St., Vancouver, V5Z 3J5 British Columbia, Canada.
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48
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Greenstein AE, Grundner C, Echols N, Gay LM, Lombana TN, Miecskowski CA, Pullen KE, Sung PY, Alber T. Structure/Function Studies of Ser/Thr and Tyr Protein Phosphorylation in Mycobacterium tuberculosis. J Mol Microbiol Biotechnol 2006; 9:167-81. [PMID: 16415590 DOI: 10.1159/000089645] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Many bacterial species express 'eukaryotic-like' Ser/Thr or Tyr protein kinases and phosphatases that are candidate mediators of developmental changes and host/pathogen interactions. The biological functions of these systems are largely unknown. Recent genetic, biochemical and structural studies have begun to establish a framework for understanding the systems for Ser/Thr and Tyr protein phosphorylation in Mycobacterium tuberculosis (Mtb). Ser/Thr protein kinases (STPKs) appear to regulate diverse processes including cell division and molecular transport. Proposed protein substrates of the STPKs include putative regulatory proteins, as well as six proteins containing Forkhead-associated domains. Structures of domains of receptor STPKs and all three Mtb Ser/Thr or Tyr phosphatases afford an initial description of the principal modules that mediate bacterial STPK signaling. These studies revealed that universal mechanisms of regulation and substrate recognition govern the functions of prokaryotic and eukaryotic STPKs. Several structures also support novel mechanisms of regulation, including dimerization of STPKs, metal-ion binding to PstP and substrate mimicry in PtpB.
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Affiliation(s)
- Andrew E Greenstein
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720-3206, USA
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49
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Cozzone AJ. Role of Protein Phosphorylation on Serine/Threonine and Tyrosine in the Virulence of Bacterial Pathogens. J Mol Microbiol Biotechnol 2006; 9:198-213. [PMID: 16415593 DOI: 10.1159/000089648] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Bacterial pathogens have developed a diversity of strategies to interact with host cells, manipulate their behaviors, and thus to survive and propagate. During the process of pathogenesis, phosphorylation of proteins on hydroxyl amino acids (serine, threonine, tyrosine) occurs at different stages, including cell-cell interaction and adherence, translocation of bacterial effectors into host cells, and changes in host cellular structure and function induced by infection. The phosphorylation reactions are catalyzed in a reversible fashion by specific protein kinases and phosphatases that belong to either the invading bacterial cells or the infected eukaryotic host cells. Among the various virulence factors involved in bacterial pathogenesis, special attention has been paid recently to the cell wall components, exopolysaccharides. A major breakthrough has been made by showing the existence of a biological link between the activity of certain protein-tyrosine kinases/phosphatases and the production and/or transport of surface polysaccharides. In addition, genetic studies have revealed a key role played by some serine/threonine kinases in pathogenesis. Considering the structural organization and membrane topology of these different kinases, it can be envisaged that they operate as one-component systems in signal transduction pathways, in the form of single proteins containing input and output domains on the same polypeptide chain. From a general standpoint, the demonstration of a direct relationship between protein phosphorylation on serine/threonine/tyrosine and bacterial virulence represents a novel concept of great importance in deciphering the molecular and cellular mechanisms that underlie pathogenesis.
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Affiliation(s)
- Alain J Cozzone
- Institute of Biology and Chemistry of Proteins, University of Lyon/CNRS, Lyon, France.
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Hestvik ALK, Hmama Z, Av-Gay Y. Mycobacterial manipulation of the host cell. FEMS Microbiol Rev 2005; 29:1041-50. [PMID: 16040149 DOI: 10.1016/j.femsre.2005.04.013] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2004] [Revised: 03/12/2005] [Accepted: 04/18/2005] [Indexed: 11/20/2022] Open
Abstract
Phagosome biogenesis, the process by which macrophages neutralize ingested pathogens and initiate antigen presentation, has entered the field of cellular mycobacteriology research largely owing to the discovery 30 years ago that phagosomes harboring mycobacteria are refractory to fusion with lysosomes. In the past decade, the use of molecular genetics and biology in different model systems to study phagosome biogenesis have made significant advances in understanding subtle mechanisms by which mycobacteria inhibit the maturation of its phagosome. Thus, we are beginning to appreciate the extent to which these pathogens are able to interfere with innate immune responses and manipulate defense mechanisms to enhance their survival within the human host cell. Here, we summarize current knowledge about phagosome maturation arrest in infected macrophages and the subsequent attenuation of the macrophage-initiated adaptive anti-mycobacterial immune defenses.
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Affiliation(s)
- Anne Lise K Hestvik
- Department of Medicine, Division of Infectious Diseases, University of British Columbia, Vancouver, British Columbia, 2733 Heather St. Vancouver, BC, Canada V5Z 3J5
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