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Santoshi M, Tare P, Nagaraja V. Nucleoid-associated proteins of mycobacteria come with a distinctive flavor. Mol Microbiol 2024. [PMID: 38922783 DOI: 10.1111/mmi.15287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 05/31/2024] [Accepted: 06/05/2024] [Indexed: 06/28/2024]
Abstract
In every bacterium, nucleoid-associated proteins (NAPs) play crucial roles in chromosome organization, replication, repair, gene expression, and other DNA transactions. Their central role in controlling the chromatin dynamics and transcription has been well-appreciated in several well-studied organisms. Here, we review the diversity, distribution, structure, and function of NAPs from the genus Mycobacterium. We highlight the progress made in our understanding of the effects of these proteins on various processes and in responding to environmental stimuli and stress of mycobacteria in their free-living as well as during distinctive intracellular lifestyles. We project them as potential drug targets and discuss future studies to bridge the information gap with NAPs from well-studied systems.
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Affiliation(s)
- Meghna Santoshi
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bengaluru, India
| | - Priyanka Tare
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bengaluru, India
| | - Valakunja Nagaraja
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bengaluru, India
- Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India
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2
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Nicholson KR, Cronin RM, Prest RJ, Menon AR, Yang Y, Jennisch MK, Champion MM, Tobin DM, Champion PA. The antagonistic transcription factors, EspM and EspN, regulate the ESX-1 secretion system in M. marinum. mBio 2024; 15:e0335723. [PMID: 38445877 PMCID: PMC11005418 DOI: 10.1128/mbio.03357-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Accepted: 02/13/2024] [Indexed: 03/07/2024] Open
Abstract
Bacterial pathogens use protein secretion systems to transport virulence factors and regulate gene expression. Among pathogenic mycobacteria, including Mycobacterium tuberculosis and Mycobacterium marinum, the ESAT-6 system 1 (ESX-1) secretion is crucial for host interaction. Secretion of protein substrates by the ESX-1 secretion system disrupts phagosomes, allowing mycobacteria cytoplasmic access during macrophage infections. Deletion or mutation of the ESX-1 system attenuates mycobacterial pathogens. Pathogenic mycobacteria respond to the presence or absence of the ESX-1 system in the cytoplasmic membrane by altering transcription. Under laboratory conditions, the EspM repressor and WhiB6 activator control transcription of specific ESX-1-responsive genes, including the ESX-1 substrate genes. However, deleting the espM or whiB6 gene does not phenocopy the deletion of the ESX-1 substrate genes during macrophage infection by M. marinum. In this study, we identified EspN, a critical transcription factor whose activity is masked by the EspM repressor under laboratory conditions. In the absence of EspM, EspN activates transcription of whiB6 and ESX-1 genes during both laboratory growth and macrophage infection. EspN is also independently required for M. marinum growth within and cytolysis of macrophages, similar to the ESX-1 genes, and for disease burden in a zebrafish larval model of infection. These findings suggest that EspN and EspM coordinate to counterbalance the regulation of the ESX-1 system and support mycobacterial pathogenesis.IMPORTANCEPathogenic mycobacteria, which are responsible for tuberculosis and other long-term diseases, use the ESX-1 system to transport proteins that control the host response to infection and promote bacterial survival. In this study, we identify an undescribed transcription factor that controls the expression of ESX-1 genes and is required for both macrophage and animal infection. However, this transcription factor is not the primary regulator of ESX-1 genes under standard laboratory conditions. These findings identify a critical transcription factor that likely controls expression of a major virulence pathway during infection, but whose effect is not detectable with standard laboratory strains and growth conditions.
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Affiliation(s)
- Kathleen R. Nicholson
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, USA
| | - Rachel M. Cronin
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, USA
| | - Rebecca J. Prest
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, USA
| | - Aruna R. Menon
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, North Carolina, USA
| | - Yuwei Yang
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, USA
| | - Madeleine K. Jennisch
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, USA
| | - Matthew M. Champion
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, USA
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - David M. Tobin
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Immunology, Duke University School of Medicine, Durham, North Carolina, USA
| | - Patricia A. Champion
- Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, USA
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Lu Y, Chen H, Wang P, Pang J, Lu X, Li G, Hu X, Wang X, Yang X, Li C, Lu Y, You X. Identification and Quantification of S-Sulfenylation Proteome of Mycobacterium tuberculosis under Oxidative Stress. Microbiol Spectr 2023; 11:e0338622. [PMID: 36943050 PMCID: PMC10101118 DOI: 10.1128/spectrum.03386-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 02/16/2023] [Indexed: 03/23/2023] Open
Abstract
The ability to maintain redox homeostasis is critical for Mycobacterium tuberculosis (Mtb) to survive the redox stress of the host. There are many antioxidant systems in Mtb to ensure its normal replication and survival in the host, and cysteine thiols are one of them. S-sulfenylation is one of the reversible modifications of cysteine thiols to resist oxidative stress. In the study, we investigated the total cysteine thiols modification and S-sulfenylation modification of Mtb proteome under the oxidative stress provided by hydrogen peroxide. To determine and quantify the S-sulfenylation modified proteins, high specific IodoTMT6plex reagents and high resolution mass spectrometry were used to label and quantify the peptides and proteins modified. There are significant differences for the total cysteine modification levels of 279 proteins and S-sulfenylation modification levels of 297 proteins under hydrogen peroxide stress. Functional enrichment analysis indicated that these cysteine-modified proteins were involved in the oxidation-reduction process, fatty acid biosynthetic process, stress response, protein repair, cell wall, etc. In conclusion, our study provides a view of cysteine modifications of the Mtb proteome under oxidative stress, revealing a series of proteins that may play a role in maintaining redox homeostasis. IMPORTANCE With the continuous spread of drug-resistant tuberculosis, there is an urgent need for new antituberculosis drugs with new mechanisms. The ability of Mtb to resist oxidative stress is extremely important for maintaining redox homeostasis and survival in the host. The reversible modifications of cysteine residues have a dual role of protection from irreversible damage to protein functions and regulation, which plays an important role in the redox homeostasis system. Thus, to discover cysteine modification changes in the proteome level under oxidative stress is quintessential to elucidate its antioxidant mechanism. Our results provided a list of proteins involved in the antioxidant process that potentially could be considered targets for drug discovery and vaccine development. Furthermore, it is the first study to determine and quantify the S-sulfenylation-modified proteins in Mtb, which provided better insight into the Mtb response to the host oxidative defense and enable a deeper understanding of Mtb survival strategies.
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Affiliation(s)
- Yun Lu
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Hongtong Chen
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Penghe Wang
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jing Pang
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xi Lu
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Guoqing Li
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xinxin Hu
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xiukun Wang
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xinyi Yang
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Congran Li
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yu Lu
- Department of Pharmacology, Beijing Chest Hospital, Capital Medical University; Beijing Key Laboratory of Drug Resistance Tuberculosis Research, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
| | - Xuefu You
- Beijing Key Laboratory of Antimicrobial Agents, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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The EspN transcription factor is an infection-dependent regulator of the ESX-1 system in M. marinum. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.15.528779. [PMID: 36824794 PMCID: PMC9948972 DOI: 10.1101/2023.02.15.528779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Bacterial pathogens use protein secretion systems to translocate virulence factors into the host and to control bacterial gene expression. The ESX-1 (ESAT-6 system 1) secretion system facilitates disruption of the macrophage phagosome during infection, enabling access to the cytoplasm, and regulates widespread gene expression in the mycobacterial cell. The transcription factors contributing to the ESX-1 transcriptional network during mycobacterial infection are not known. We showed that the EspM and WhiB6 transcription factors regulate the ESX-1 transcriptional network in vitro but are dispensable for macrophage infection by Mycobacterium marinum . In this study, we used our understanding of the ESX-1 system to identify EspN, a critical transcription factor that controls expression of the ESX-1 genes during infection, but whose effect is not detectable under standard laboratory growth conditions. Under laboratory conditions, EspN activity is masked by the EspM repressor. In the absence of EspM, we found that EspN is required for ESX-1 function because it activates expression of the whiB6 transcription factor gene, and specific ESX-1 substrate and secretory component genes. Unlike the other transcription factors that regulate ESX-1, EspN is required for M. marinum growth within and cytolysis of macrophages, and for disease burden in a zebrafish larval model of infection. These findings demonstrate that EspN is an infection-dependent regulator of the ESX-1 transcriptional network, which is essential for mycobacterial pathogenesis. Moreover, our findings suggest that ESX-1 expression is controlled by a genetic switch that responds to host specific signals. Importance Pathogenic mycobacteria cause acute and long-term diseases, including human tuberculosis. The ESX-1 system transports proteins that control the host response to infection and promotes bacterial survival. Although ESX-1 transports proteins, it also controls gene expression in the bacteria. In this study, we identify an undescribed transcription factor that controls the expression of ESX-1 genes, and is required for both macrophage and animal infection. However, this transcription factor is not the primary regulator of ESX-1 genes under standard laboratory conditions. These findings identify a critical transcription factor that controls expression of a major virulence pathway during infection, but whose effect is not detectable with standard laboratory strains and growth conditions.
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Genestet C, Refrégier G, Hodille E, Zein-Eddine R, Le Meur A, Hak F, Barbry A, Westeel E, Berland JL, Engelmann A, Verdier I, Lina G, Ader F, Dray S, Jacob L, Massol F, Venner S, Dumitrescu O. Mycobacterium tuberculosis genetic features associated with pulmonary tuberculosis severity. Int J Infect Dis 2022; 125:74-83. [PMID: 36273524 DOI: 10.1016/j.ijid.2022.10.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 10/13/2022] [Accepted: 10/15/2022] [Indexed: 11/06/2022] Open
Abstract
OBJECTIVES Mycobacterium tuberculosis (Mtb) infections result in a wide spectrum of clinical presentations but without proven Mtb genetic determinants. Herein, we hypothesized that the genetic features of Mtb clinical isolates, such as specific polymorphisms or microdiversity, may be linked to tuberculosis (TB) severity. METHODS A total of 234 patients with pulmonary TB (including 193 drug-susceptible and 14 monoresistant cases diagnosed between 2017 and 2020 and 27 multidrug-resistant cases diagnosed between 2010 and 2020) were stratified according to TB disease severity, and Mtb genetic features were explored using whole genome sequencing, including heterologous single-nucleotide polymorphism (SNP), calling to explore microdiversity. Finally, we performed a structural equation modeling analysis to relate TB severity to Mtb genetic features. RESULTS The clinical isolates from patients with mild TB carried mutations in genes associated with host-pathogen interaction, whereas those from patients with moderate/severe TB carried mutations associated with regulatory mechanisms. Genome-wide association study identified an SNP in the promoter of the gene coding for the virulence regulator espR, statistically associated with moderate/severe disease. Structural equation modeling and model comparisons indicated that TB severity was associated with the detection of Mtb microdiversity within clinical isolates and to the espR SNP. CONCLUSION Taken together, these results provide a new insight to better understand TB pathophysiology and could provide a new prognosis tool for pulmonary TB severity.
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Affiliation(s)
- Charlotte Genestet
- CIRI - Centre International de Recherche en Infectiologie, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon-1, Rhône-Alpes, Lyon, France; Hospices Civils de Lyon, Institut des Agents Infectieux, Laboratoire de bactériologie, Rhône-Alpes, Lyon, France.
| | - Guislaine Refrégier
- Université Paris-Saclay, CNRS, AgroParisTech, Ecologie Systématique et Evolution, Île-de-France, Orsay, France.; Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris Sud, Université Paris-Saclay, Île-de-France, Gif-sur-Yvette, France
| | - Elisabeth Hodille
- CIRI - Centre International de Recherche en Infectiologie, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon-1, Rhône-Alpes, Lyon, France; Hospices Civils de Lyon, Institut des Agents Infectieux, Laboratoire de bactériologie, Rhône-Alpes, Lyon, France
| | - Rima Zein-Eddine
- Université Paris-Saclay, CNRS, AgroParisTech, Ecologie Systématique et Evolution, Île-de-France, Orsay, France.; Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris Sud, Université Paris-Saclay, Île-de-France, Gif-sur-Yvette, France; Laboratory of Optics and Biosciences, CNRS-INSERM-Ecole Polytechnique, Île-de-France, Palaiseau, France
| | - Adrien Le Meur
- Université Paris-Saclay, CNRS, AgroParisTech, Ecologie Systématique et Evolution, Île-de-France, Orsay, France.; Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris Sud, Université Paris-Saclay, Île-de-France, Gif-sur-Yvette, France
| | - Fiona Hak
- Université Paris-Saclay, CNRS, AgroParisTech, Ecologie Systématique et Evolution, Île-de-France, Orsay, France.; Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris Sud, Université Paris-Saclay, Île-de-France, Gif-sur-Yvette, France
| | - Alexia Barbry
- CIRI - Centre International de Recherche en Infectiologie, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon-1, Rhône-Alpes, Lyon, France; Hospices Civils de Lyon, Institut des Agents Infectieux, Laboratoire de bactériologie, Rhône-Alpes, Lyon, France
| | - Emilie Westeel
- Fondation Mérieux, Emerging Pathogens Laboratory, Rhône-Alpes, Lyon, France
| | - Jean-Luc Berland
- Fondation Mérieux, Emerging Pathogens Laboratory, Rhône-Alpes, Lyon, France
| | - Astrid Engelmann
- Centre Hospitalier Fleyriat, Rhône-Alpes, Bourg-en-Bresse, France
| | - Isabelle Verdier
- Centre Hospitalier Fleyriat, Rhône-Alpes, Bourg-en-Bresse, France
| | - Gérard Lina
- CIRI - Centre International de Recherche en Infectiologie, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon-1, Rhône-Alpes, Lyon, France; Hospices Civils de Lyon, Institut des Agents Infectieux, Laboratoire de bactériologie, Rhône-Alpes, Lyon, France; Université Lyon 1, Facultés de Médecine et de Pharmacie de Lyon, Rhône-Alpes, Lyon, France
| | - Florence Ader
- CIRI - Centre International de Recherche en Infectiologie, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon-1, Rhône-Alpes, Lyon, France; Hospices Civils de Lyon, Service des Maladies infectieuses et tropicales, Rhône-Alpes, Lyon, France
| | - Stéphane Dray
- Biometrics and Evolutionary Biology Laboratory, CNRS UMR 5558, Université Lyon 1, Rhône-Alpes, Villeurbanne, France
| | - Laurent Jacob
- Biometrics and Evolutionary Biology Laboratory, CNRS UMR 5558, Université Lyon 1, Rhône-Alpes, Villeurbanne, France
| | - François Massol
- UMR 8198 Evo-Eco-Paleo, SPICI Group, University of Lille, Hauts-de-France, Lille, France; CNRS, CHU Lille, Institut Pasteur de Lille, U1019-UMR 9017-CIIL-Center for Infection and Immunity of Lille, University of Lille, Hauts-de-France, Lille, France
| | - Samuel Venner
- Biometrics and Evolutionary Biology Laboratory, CNRS UMR 5558, Université Lyon 1, Rhône-Alpes, Villeurbanne, France
| | - Oana Dumitrescu
- CIRI - Centre International de Recherche en Infectiologie, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon-1, Rhône-Alpes, Lyon, France; Hospices Civils de Lyon, Institut des Agents Infectieux, Laboratoire de bactériologie, Rhône-Alpes, Lyon, France; Université Lyon 1, Facultés de Médecine et de Pharmacie de Lyon, Rhône-Alpes, Lyon, France
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Singh N, Sharma N, Singh P, Pandey M, Ilyas M, Sisodiya L, Choudhury T, Gosain TP, Singh R, Atmakuri K. HupB, a nucleoid-associated protein, is critical for survival of Mycobacterium tuberculosis under host-mediated stresses and for enhanced tolerance to key first-line antibiotics. Front Microbiol 2022; 13:937970. [PMID: 36071978 PMCID: PMC9441915 DOI: 10.3389/fmicb.2022.937970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 07/12/2022] [Indexed: 11/30/2022] Open
Abstract
To survive and establish its niche, Mycobacterium tuberculosis (Mtb) engages in a steady battle against an array of host defenses and a barrage of antibiotics. Here, we demonstrate that Mtb employs HupB, a nucleoid-associated protein (NAP) as its key player to simultaneously battle and survive in these two stress-inducing fronts. Typically, NAPs are key to bacterial survival under a wide array of environmental or host-mediated stresses. Here, we report that for Mtb to survive under different macrophage-induced assaults including acidic pH, nutrient depletion, oxidative and nitrosative stresses, HupB presence is critical. As expected, the hupB knockout mutant is highly sensitive to these host-mediated stresses. Furthermore, Mtb aptly modulates HupB protein levels to overcome these stresses. We also report that HupB aids Mtb to gain tolerance to high levels of rifampicin (RIF) and isoniazid (INH) exposure. Loss of hupB makes Mtb highly susceptible to even short exposures to reduced amounts of RIF and INH. Overexpressing hupB in Mtb or complementing hupB in the hupB knockout mutant triggers enhanced survival of Mtb under these stresses. We also find that upon loss of hupB, Mtb significantly enhances the permeability of its cell wall by modulating the levels of several surface lipids including phthiocerol dimycocerosates (PDIMs), thus possibly influencing overall susceptibility to host-mediated stresses. Loss of hupB also downregulates efflux pump expression possibly influencing increased susceptibility to INH and RIF. Finally, we find that therapeutic targeting of HupB with SD1, a known small molecule inhibitor, significantly enhances Mtb susceptibility to INH and THP-1 macrophages and significantly reduces MIC to INH. Thus, our data strongly indicate that HupB is a highly promising therapeutic target especially for potential combinatorial shortened therapy with reduced INH and RIF doses.
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Affiliation(s)
- Niti Singh
- Infection and Immunology Group, Translational Health Science and Technology Institute, Faridabad, Haryana, India
- Manipal University, Manipal, Karnataka, India
| | - Nishant Sharma
- Infection and Immunology Group, Translational Health Science and Technology Institute, Faridabad, Haryana, India
| | - Padam Singh
- Infection and Immunology Group, Translational Health Science and Technology Institute, Faridabad, Haryana, India
| | - Manitosh Pandey
- Infection and Immunology Group, Translational Health Science and Technology Institute, Faridabad, Haryana, India
- Department of Life Sciences, ITM University, Gwalior, Madhya Pradesh, India
| | - Mohd Ilyas
- Infection and Immunology Group, Translational Health Science and Technology Institute, Faridabad, Haryana, India
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Lovely Sisodiya
- Infection and Immunology Group, Translational Health Science and Technology Institute, Faridabad, Haryana, India
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Tejaswini Choudhury
- Infection and Immunology Group, Translational Health Science and Technology Institute, Faridabad, Haryana, India
| | - Tannu Priya Gosain
- Infection and Immunology Group, Translational Health Science and Technology Institute, Faridabad, Haryana, India
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Ramandeep Singh
- Infection and Immunology Group, Translational Health Science and Technology Institute, Faridabad, Haryana, India
| | - Krishnamohan Atmakuri
- Infection and Immunology Group, Translational Health Science and Technology Institute, Faridabad, Haryana, India
- *Correspondence: Krishnamohan Atmakuri
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7
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Multiplexed Strain Phenotyping Defines Consequences of Genetic Diversity in Mycobacterium tuberculosis for Infection and Vaccination Outcomes. mSystems 2022; 7:e0011022. [PMID: 35430871 PMCID: PMC9239107 DOI: 10.1128/msystems.00110-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
There is growing evidence that genetic diversity in Mycobacterium tuberculosis, the causative agent of tuberculosis, contributes to the outcomes of infection and public health interventions, such as vaccination. Epidemiological studies suggest that among the phylogeographic lineages of M. tuberculosis, strains belonging to a sublineage of Lineage 2 (mL2) are associated with concerning clinical features, including hypervirulence, treatment failure, and vaccine escape. The global expansion and increasing prevalence of this sublineage has been attributed to the selective advantage conferred by these characteristics, yet confounding host and environmental factors make it difficult to identify the bacterial determinants driving these associations in human studies. Here, we developed a molecular barcoding strategy to facilitate high-throughput, experimental phenotyping of M. tuberculosis clinical isolates. This approach allowed us to characterize growth dynamics for a panel of genetically diverse M. tuberculosis strains during infection and after vaccination in the mouse model. We found that mL2 strains exhibit distinct growth dynamics in vivo and are resistant to the immune protection conferred by Bacillus Calmette-Guerin (BCG) vaccination. The latter finding corroborates epidemiological observations and demonstrates that mycobacterial features contribute to vaccine efficacy. To investigate the genetic and biological basis of mL2 strains’ distinctive phenotypes, we performed variant analysis, transcriptional studies, and genome-wide transposon sequencing. We identified functional genetic changes across multiple stress and host response pathways in a representative mL2 strain that are associated with variants in regulatory genes. These adaptive changes may underlie the distinct clinical characteristics and epidemiological success of this lineage. IMPORTANCE Tuberculosis, caused by the bacterium Mycobacterium tuberculosis, is a remarkably heterogeneous disease, a feature that complicates clinical care and public health interventions. The contributions of pathogen genetic diversity to this heterogeneity are uncertain, in part due to the challenges of experimentally manipulating M. tuberculosis, a slow-growing, biosafety level 3 organism. To overcome these challenges, we applied a molecular barcoding strategy to a panel of M. tuberculosis clinical isolates. This novel application of barcoding permitted the high-throughput characterization of M. tuberculosis strain growth dynamics and vaccine resistance in the mouse model of infection. Integrating these results with genomic analyses, we uncover bacterial pathways that contribute to infection outcomes, suggesting targets for improved therapeutics and vaccines.
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8
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Stupar M, Furness J, De Voss CJ, Tan L, West NP. Two-component sensor histidine kinases of Mycobacterium tuberculosis: beacons for niche navigation. Mol Microbiol 2022; 117:973-985. [PMID: 35338720 PMCID: PMC9321153 DOI: 10.1111/mmi.14899] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 03/12/2022] [Accepted: 03/22/2022] [Indexed: 11/27/2022]
Abstract
Intracellular bacterial pathogens such as Mycobacterium tuberculosis are remarkably adept at surviving within a host, employing a variety of mechanisms to counteract host defenses and establish a protected niche. Constant surveying of the environment is key for pathogenic mycobacteria to discern their immediate location and coordinate the expression of genes necessary for adaptation. Two‐component systems efficiently perform this role, typically comprised of a transmembrane sensor kinase and a cytoplasmic response regulator. In this review, we describe the role of two‐component systems in bacterial pathogenesis, focusing predominantly on the role of sensor kinases of M. tuberculosis. We highlight important features of sensor kinases in mycobacterial infection, discuss ways in which these signaling proteins sense and respond to environments, and how this is attuned to their intracellular lifestyle. Finally, we discuss recent studies which have identified and characterized inhibitors of two‐component sensor kinases toward establishing a new strategy in anti‐mycobacterial therapy.
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Affiliation(s)
- Miljan Stupar
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, University of Queensland, Brisbane, 4072, Australia
| | - Juanelle Furness
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, University of Queensland, Brisbane, 4072, Australia
| | - Christopher J De Voss
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, University of Queensland, Brisbane, 4072, Australia
| | - Lendl Tan
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, University of Queensland, Brisbane, 4072, Australia
| | - Nicholas P West
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, University of Queensland, Brisbane, 4072, Australia
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9
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Sharma S, Sharma M. Proline-Glutamate/Proline-Proline-Glutamate (PE/PPE) proteins of Mycobacterium tuberculosis: The multifaceted immune-modulators. Acta Trop 2021; 222:106035. [PMID: 34224720 DOI: 10.1016/j.actatropica.2021.106035] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 06/23/2021] [Accepted: 06/29/2021] [Indexed: 12/30/2022]
Abstract
The PE/PPE proteins encoded by seven percent (7%) of Mycobacterium tuberculosis (Mtb) genome are the chief constituents to pathogen's virulence reservoir. The fact that these genes have evolved along ESX secretory system in pathogenic Mtb strains make their investigation very intriguing. There is lot of speculation about the prominent role of these proteins at host pathogen interface and in disease pathogenesis. Nevertheless, the exact function of PE/PPE proteins still remains a mystery which calls for further research targeting these proteins. This article is an effort to document all the facts known so far with regard to these unique proteins which involves their origin, evolution, transcriptional control, and most important their role as host immune-modulators. Our understanding strongly points towards the versatile nature of these PE/PPE proteins as Mtb's host immune sensors and as decisive factors in shaping the outcome of infection. Further investigation on these proteins will surely pave way for newer and effective vaccines and therapeutics to control Tuberculosis (TB).
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Affiliation(s)
- Sadhna Sharma
- DS Kothari Central Interdisciplinary Research Centre and Department of Zoology, Miranda House, University of Delhi, Delhi 110007, India.
| | - Monika Sharma
- DS Kothari Central Interdisciplinary Research Centre and Department of Zoology, Miranda House, University of Delhi, Delhi 110007, India.
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10
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Thamilselvan G, Sarveswari HB, Vasudevan S, Stanley A, Shanmugam K, Vairaprakash P, Solomon AP. Development of an Antibiotic Resistance Breaker to Resensitize Drug-Resistant Staphylococcus aureus: In Silico and In Vitro Approach. Front Cell Infect Microbiol 2021; 11:700198. [PMID: 34485178 PMCID: PMC8415528 DOI: 10.3389/fcimb.2021.700198] [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: 04/25/2021] [Accepted: 07/20/2021] [Indexed: 12/24/2022] Open
Abstract
Efflux pumps are one of the predominant microbial resistant mechanisms leading to the development of multidrug resistance. In Staphylococcus aureus, overexpression of NorA protein enables the efflux of antibiotics belonging to the class of fluoroquinolones and, thus, makes S. aureus resistant. Hence, NorA efflux pumps are being extensively exploited as the potential drug target to evade bacterial resistance and resensitize bacteria to the existing antibiotics. Although several molecules are reported to inhibit NorA efflux pump effectively, boronic acid derivatives were shown to have promising NorA efflux pump inhibition. In this regard, the current study exploits 6-(3-phenylpropoxy)pyridine-3-boronic acid to further improve the activity and reduce cytotoxicity using the bioisostere approach, a classical medicinal chemistry concept. Using the SWISS-Bioisostere online tool, from the parent compound, 42 compounds were obtained upon the replacement of the boronic acid. The 42 compounds were docked with modeled NorA protein, and key molecular interactions of the prominent compounds were assessed. The top hit compounds were further analyzed for their drug-like properties using ADMET studies. The identified potent lead, 5-nitro-2-(3-phenylpropoxy)pyridine (5-NPPP), was synthesized, and in vitro efficacy studies have been proven to show enhanced efflux inhibition, thus acting as a potent antibiotic breaker to resensitize S. aureus without elucidating any cytotoxic effect to the host Hep-G2 cell lines.
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Affiliation(s)
- Gopalakrishnan Thamilselvan
- Quorum Sensing Laboratory, Centre of Research in Infectious Diseases, School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Hema Bhagavathi Sarveswari
- Quorum Sensing Laboratory, Centre of Research in Infectious Diseases, School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Sahana Vasudevan
- Quorum Sensing Laboratory, Centre of Research in Infectious Diseases, School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Alex Stanley
- Department of Bioinformatics, School of Chemical & Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Karthi Shanmugam
- Quorum Sensing Laboratory, Centre of Research in Infectious Diseases, School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India.,Department of Bioinformatics, School of Chemical & Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Pothiappan Vairaprakash
- Department of Chemistry, School of Chemical & Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Adline Princy Solomon
- Quorum Sensing Laboratory, Centre of Research in Infectious Diseases, School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
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11
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The PhoPR two-component system responds to oxygen deficiency and regulates the pathways for energy supply in Corynebacterium glutamicum. World J Microbiol Biotechnol 2021; 37:160. [PMID: 34436681 DOI: 10.1007/s11274-021-03131-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 08/18/2021] [Indexed: 10/20/2022]
Abstract
The PhoPR two-component system, a highly conserved system in corynebacteria and mycobacteria, is involved in the cellular response to environmental stress. When analysing the transcriptomic data of Corynebacterium glutamicum strains under different dissolved oxygen (DO) levels, PhoPR was found to be the most responsive two-component system to DO changes. Here, we systematically investigated the expression of PhoPR in response to different DO levels and its impact on genes related to global regulation and energy metabolism. Using Green fluorescent protein as a reporter, we confirmed that PhoPR was significantly upregulated upon decrease of DO. Through real-time quantitative PCR and electrophoretic mobility shift assay, we found that the effector protein PhoP directly activated glxR (encoding a global regulator), pfk and gapA (encoding the glycolytic enzymes) and ctaD (encoding cytochrome c in the electron transport chain), while downregulated aceE and gltA (encoding the TCA cycle enzymes). Overexpression of phoP or phoR resulted in a decreased intracellular NAD+/NADH ratio and increased intracellular ATP level, consistent with the gene expression changes regulated by PhoP. These results reveal the PhoPR system respond to oxygen deficiency and is responsible for the regulation of pathways involved in the sustainability of the energy levels required under low oxygen conditions. Our findings in this study not only provide new insights into the adaptation pathways of C. glutamicum in response to low oxygen conditions but also identify new possible genetic targets for the construction of the new cell factories aimed toward industrial applications.
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12
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Zhu Y, Zhang P, Zhang J, Xu W, Wang X, Wu L, Sheng D, Ma W, Cao G, Chen XL, Lu Y, Zhang YZ, Pang X. The developmental regulator MtrA binds GlnR boxes and represses nitrogen metabolism genes in Streptomyces coelicolor. Mol Microbiol 2019; 112:29-46. [PMID: 30927282 DOI: 10.1111/mmi.14252] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/23/2019] [Indexed: 12/25/2022]
Abstract
In Streptomyces, GlnR is an activator protein that activates nitrogen-assimilation genes under nitrogen-limiting conditions. However, less is known regarding the regulation of these genes under nitrogen-rich conditions. We determined that the developmental regulator MtrA represses nitrogen-assimilation genes in nitrogen-rich media and that it competes with GlnR for binding to GlnR boxes. The GlnR boxes upstream of multiple nitrogen genes, such as amtB, were confirmed as MtrA binding sites in vitro by electrophoretic mobility shift assays and in vivo by ChIP-qPCR analysis. Transcriptional analysis indicated that, on nutrient-rich medium, MtrA profoundly repressed expression of nitrogen-associated genes, indicating opposing roles for MtrA and GlnR in the control of nitrogen metabolism. Using in vitro and in vivo analysis, we also showed that glnR is itself a direct target of MtrA and that MtrA represses glnR transcription. We further demonstrated functional conservation of MtrA homologues in the recognition of GlnR boxes upstream of nitrogen genes from different actinobacterial species. As mtrA and glnR are widespread among actinomycetes, this mechanism of potential competitive control over nitrogen metabolism genes may be common in this group, adding a major new layer of complexity to the known regulatory network for nitrogen metabolism in Streptomyces and related species.
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Affiliation(s)
- Yanping Zhu
- The State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China
| | - Peipei Zhang
- The State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China.,Shandong Medicinal Biotechnology Center, Shandong Academy of Medical Sciences, Jinan, 250062, China
| | - Jing Zhang
- The State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China
| | - Wenhao Xu
- The State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China
| | - Xinyuan Wang
- The State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China
| | - Lili Wu
- The State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China
| | - Duohong Sheng
- The State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China
| | - Wei Ma
- The State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Guangxiang Cao
- Shandong Medicinal Biotechnology Center, Shandong Academy of Medical Sciences, Jinan, 250062, China
| | - Xiu-Lan Chen
- The State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China
| | - Yinhua Lu
- College of Life Sciences, Shanghai Normal University, Shanghai, 200232, China
| | - Yu-Zhong Zhang
- The State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China.,College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China
| | - Xiuhua Pang
- The State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China
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13
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Novel Two-Component System MacRS Is a Pleiotropic Regulator That Controls Multiple Morphogenic Membrane Protein Genes in Streptomyces coelicolor. Appl Environ Microbiol 2019; 85:AEM.02178-18. [PMID: 30530707 DOI: 10.1128/aem.02178-18] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 11/28/2018] [Indexed: 11/20/2022] Open
Abstract
As with most annotated two-component systems (TCSs) of Streptomyces coelicolor, the function of TCS SCO2120/2121 was unknown. Based on our findings, we have designated this TCS MacRS, for morphogenesis and actinorhodin regulator/sensor. Our study indicated that either single or double mutation of MacRS largely blocked production of actinorhodin but enhanced formation of aerial mycelium. Chromatin immunoprecipitation (ChIP) sequencing, using an S. coelicolor strain expressing MacR-Flag fusion protein, identified in vivo targets of MacR, and DNase I footprinting of these targets revealed a consensus sequence for MacR binding, TGAGTACnnGTACTCA, containing two 7-bp inverted repeats. A genome-wide search revealed sites identical or highly similar to this consensus sequence upstream of six genes encoding putative membrane proteins or lipoproteins. These predicted sites were confirmed as MacR binding sites by DNase I footprinting and electrophoretic mobility shift assays in vitro and by ChIP-quantitative PCR in vivo, and transcriptional analyses demonstrated that MacR significantly impacts expression of these target genes. Disruption of three of these genes, sco6728, sco4924, and sco4011, markedly accelerated aerial mycelium formation, indicating that their gene products are novel morphogenic factors. Two-hybrid assays indicated that these three proteins, which we have named morphogenic membrane protein A (MmpA; SCO6728), MmpB (SCO4924), and MmpC (SCO4011), interact with one another and with the putative membrane protein and MacR target SCO4225. Notably, SAV6081/82 and SVEN1780/81, homologs of MacRS TCS from S. avermitilis and S. venezuelae, respectively, can substitute for MacRS, indicating functional conservation. Our findings reveal a role for MacRS in cellular morphogenesis and secondary metabolism in Streptomyces IMPORTANCE TCSs help bacteria adapt to environmental stresses by altering gene expression. However, the roles and corresponding regulatory mechanisms of most TCSs in the Streptomyces model strain S. coelicolor are unknown. We investigated the previously uncharacterized MacRS TCS and identified the core DNA recognition sequence, two seven-nucleotide inverted repeats, for the DNA-binding protein MacR. We further found that MacR directly controls a group of membrane proteins, including MmpA-C, which are novel morphogenic factors that delay formation of aerial mycelium. We also discovered that these membrane proteins interact with one another and that other Streptomyces species have conserved MacRS homologs. Our findings suggest a conserved role for MacRS in morphogenesis and/or other membrane-associated activities. Additionally, our study showed that MacRS impacts, albeit indirectly, the production of the signature metabolite actinorhodin, further suggesting that MacRS and its homologs function as novel pleiotropic regulatory systems in Streptomyces.
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14
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Abdallah AM, Weerdenburg EM, Guan Q, Ummels R, Borggreve S, Adroub SA, Malas TB, Naeem R, Zhang H, Otto TD, Bitter W, Pain A. Integrated transcriptomic and proteomic analysis of pathogenic mycobacteria and their esx-1 mutants reveal secretion-dependent regulation of ESX-1 substrates and WhiB6 as a transcriptional regulator. PLoS One 2019; 14:e0211003. [PMID: 30673778 PMCID: PMC6343904 DOI: 10.1371/journal.pone.0211003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2018] [Accepted: 01/04/2019] [Indexed: 12/14/2022] Open
Abstract
The mycobacterial type VII secretion system ESX-1 is responsible for the secretion of a number of proteins that play important roles during host infection. The regulation of the expression of secreted proteins is often essential to establish successful infection. Using transcriptome sequencing, we found that the abrogation of ESX-1 function in Mycobacterium marinum leads to a pronounced increase in gene expression levels of the espA operon during the infection of macrophages. In addition, the disruption of ESX-1-mediated protein secretion also leads to a specific down-regulation of the ESX-1 substrates, but not of the structural components of this system, during growth in culture medium. This effect is observed in both M. marinum and M. tuberculosis. We established that down-regulation of ESX-1 substrates is the result of a regulatory process that is influenced by the putative transcriptional regulator whib6, which is located adjacent to the esx-1 locus. In addition, the overexpression of the ESX-1-associated PE35/PPE68 protein pair resulted in a significantly increased secretion of the ESX-1 substrate EsxA, demonstrating a functional link between these proteins. Taken together, these data show that WhiB6 is required for the secretion-dependent regulation of ESX-1 substrates and that ESX-1 substrates are regulated independently from the structural components, both during infection and as a result of active secretion.
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Affiliation(s)
- Abdallah M. Abdallah
- Pathogen Genomics Laboratory, BESE Division, King Abdullah University of Science and Technology (KAUST), Thuwal-Jeddah, Kingdom of Saudi Arabia
- * E-mail: (AMA); (WB); (AP)
| | - Eveline M. Weerdenburg
- Department of Medical Microbiology and Infection Control, VU University Medical Center, Amsterdam, The Netherlands
| | - Qingtian Guan
- Pathogen Genomics Laboratory, BESE Division, King Abdullah University of Science and Technology (KAUST), Thuwal-Jeddah, Kingdom of Saudi Arabia
| | - Roy Ummels
- Department of Medical Microbiology and Infection Control, VU University Medical Center, Amsterdam, The Netherlands
| | - Stephanie Borggreve
- Department of Medical Microbiology and Infection Control, VU University Medical Center, Amsterdam, The Netherlands
| | - Sabir A. Adroub
- Pathogen Genomics Laboratory, BESE Division, King Abdullah University of Science and Technology (KAUST), Thuwal-Jeddah, Kingdom of Saudi Arabia
| | - Tareq B. Malas
- Pathogen Genomics Laboratory, BESE Division, King Abdullah University of Science and Technology (KAUST), Thuwal-Jeddah, Kingdom of Saudi Arabia
| | - Raeece Naeem
- Pathogen Genomics Laboratory, BESE Division, King Abdullah University of Science and Technology (KAUST), Thuwal-Jeddah, Kingdom of Saudi Arabia
| | - Huoming Zhang
- Bioscience Core Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal-Jeddah, Kingdom of Saudi Arabia
| | - Thomas D. Otto
- Pathogen Genomics, The Wellcome Trust Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - Wilbert Bitter
- Department of Medical Microbiology and Infection Control, VU University Medical Center, Amsterdam, The Netherlands
- * E-mail: (AMA); (WB); (AP)
| | - Arnab Pain
- Pathogen Genomics Laboratory, BESE Division, King Abdullah University of Science and Technology (KAUST), Thuwal-Jeddah, Kingdom of Saudi Arabia
- * E-mail: (AMA); (WB); (AP)
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15
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Li W, Deng W, Xie J. Expression and regulatory networks of Mycobacterium tuberculosis PE/PPE family antigens. J Cell Physiol 2018; 234:7742-7751. [PMID: 30478834 DOI: 10.1002/jcp.27608] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 09/21/2018] [Indexed: 01/06/2023]
Abstract
PE/PPE family antigens are distributed mainly in pathogenic mycobacteria and serve as potential antituberculosis (TB) vaccine components. Some PE/PPE family antigens can regulate the host innate immune response, interfere with macrophage activation and phagolysosome fusion, and serve as major sources of antigenic variation. PE/PPE antigens have been associated with mycobacteria pathogenesis; pe/ppe genes are mainly found in pathogenic mycobacteria and are differentially expressed between Mtb and Mycobacterium bovis. PE/PPE proteins were essential for the growth of Mtb, and PE/PPE proteins were differentially expressed under a variety of conditions. Multiple mycobacterial-virulence-related transcription factors, sigma factors, the global transcriptional regulation factor Lsr2, MprAB, and PhoPR two-component regulatory systems, and cyclic adenine monophosphate-dependent regulators, regulate the expression of PE/PPE family antigens. Multiple-scale integrative analysis revealed the expression and regulatory networks of PE/PPE family antigens underlying the virulence and pathogenesis of Mtb, providing important clues for the discovery of new anti-TB measures.
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Affiliation(s)
- Wu Li
- Key Laboratory of Regional Characteristic Agricultural Resources, College of Life Sciences, Neijiang Normal University, Neijiang, China
| | - Wanyan Deng
- Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, Department of Infectious Diseases, The Second Affiliated Hospital, Chongqing Medical University, Chongqing, China
| | - 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-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Beibei, Chongqing, China
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16
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Novel MprA binding motifs in the phoP regulatory region in Mycobacterium tuberculosis. Tuberculosis (Edinb) 2018; 112:62-68. [PMID: 30205970 DOI: 10.1016/j.tube.2018.08.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 07/31/2018] [Accepted: 08/02/2018] [Indexed: 11/20/2022]
Abstract
MprAB and PhoPR are important two-component systems (TCSs) in Mycobacterium tuberculosis, and both regulate EspR, a key regulator of the ESX-1 secretion system. Although previous studies suggest that the response regulator PhoP does not directly regulate mprA, the interplay between MprAB and PhoPR remains unclear. In this study, we found that the response regulator MprA can bind to the phoP promoter. Four repeat motifs, D1-D4, constituting two predicted binding sites, were located in the region protected by MprA in DNA footprinting. D1-D4 lack the reported conserved MprA binding sequences, indicating that MprA can recognize a greater range of target sites. Interestingly, D1-D2 overlap a previously reported PhoP binding site, and mutation of D1-D2 inhibited PhoP binding, whereas the D3-D4 site, but not the D1-D2 site, was required for MprA binding. EMSA assays also suggest that MprA and PhoP compete to bind to the phoP promoter. The results of the transcriptional and western blot assays are consistent with a model in which MprA positively controls the phoP expression, which in turn upregulates the expression of espR. These findings reveal complex regulation of a major mycobacterial TCS by dual TCSs.
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17
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Malone KM, Rue-Albrecht K, Magee DA, Conlon K, Schubert OT, Nalpas NC, Browne JA, Smyth A, Gormley E, Aebersold R, MacHugh DE, Gordon SV. Comparative 'omics analyses differentiate Mycobacterium tuberculosis and Mycobacterium bovis and reveal distinct macrophage responses to infection with the human and bovine tubercle bacilli. Microb Genom 2018; 4. [PMID: 29557774 PMCID: PMC5885015 DOI: 10.1099/mgen.0.000163] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Members of the Mycobacterium tuberculosis complex (MTBC) are the causative agents of tuberculosis in a range of mammals, including humans. A key feature of MTBC pathogens is their high degree of genetic identity yet distinct host tropism. Notably, while Mycobacterium bovis is highly virulent and pathogenic for cattle, the human pathogen M. tuberculosis is attenuated in cattle. Previous research also suggests that host preference amongst MTBC members has a basis in host innate immune responses. To explore MTBC host tropism, we present in-depth profiling of the MTBC reference strains M. bovis AF2122/97 and M. tuberculosis H37Rv at both the global transcriptional and the translational level via RNA-sequencing and SWATH MS. Furthermore, a bovine alveolar macrophage infection time course model was used to investigate the shared and divergent host transcriptomic response to infection with M. tuberculosis H37Rv or M. bovis AF2122/97. Significant differential expression of virulence-associated pathways between the two bacilli was revealed, including the ESX-1 secretion system. A divergent transcriptional response was observed between M. tuberculosis H37Rv and M. bovis AF2122/97 infection of bovine alveolar macrophages, in particular cytosolic DNA-sensing pathways at 48 h post-infection, and highlights a distinct engagement of M. bovis with the bovine innate immune system. The work presented here therefore provides a basis for the identification of host innate immune mechanisms subverted by virulent host-adapted mycobacteria to promote their survival during the early stages of infection.
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Affiliation(s)
- Kerri M Malone
- 1UCD School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland.,†Present address: European Bioinformatics Institute (EMBL-EBI), Wellcome Genome Campus, Hinxton, Cambridge CB10 1SD, UK
| | - Kévin Rue-Albrecht
- 1UCD School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland.,2Animal Genomics Laboratory, UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland.,‡Present address: Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Headington, Oxford OX3 7FY, UK
| | - David A Magee
- 2Animal Genomics Laboratory, UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - Kevin Conlon
- 1UCD School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland
| | - Olga T Schubert
- 3Department of Biology, Institute of Molecular Systems Biology, ETH Zurich, Zurich CH-8093, Switzerland.,§Present address: Department of Human Genetics, University of California, Los Angeles, USA
| | - Nicolas C Nalpas
- 2Animal Genomics Laboratory, UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland.,¶Present address: Quantitative Proteomics and Proteome Centre Tübingen, Interfaculty Institute for Cell Biology, University of Tübingen, 72076 Tübingen, Germany
| | - John A Browne
- 2Animal Genomics Laboratory, UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - Alicia Smyth
- 1UCD School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland
| | - Eamonn Gormley
- 4Tuberculosis Diagnostics and Immunology Research Centre, UCD School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland
| | - Ruedi Aebersold
- 3Department of Biology, Institute of Molecular Systems Biology, ETH Zurich, Zurich CH-8093, Switzerland
| | - David E MacHugh
- 2Animal Genomics Laboratory, UCD School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland.,5UCD Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland
| | - Stephen V Gordon
- 5UCD Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland.,6UCD School of Medicine, University College Dublin, Dublin 4, Ireland.,1UCD School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland.,7UCD School of Biomolecular and Biomedical Science, University College Dublin, Dublin 4, Ireland
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18
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Kriel NL, Gallant J, van Wyk N, van Helden P, Sampson SL, Warren RM, Williams MJ. Mycobacterial nucleoid associated proteins: An added dimension in gene regulation. Tuberculosis (Edinb) 2018. [DOI: 10.1016/j.tube.2017.12.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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19
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Deletion of the β-Propeller Protein Gene Rv1057 Reduces ESAT-6 Secretion and Intracellular Growth of Mycobacterium tuberculosis. Curr Microbiol 2017; 75:401-409. [DOI: 10.1007/s00284-017-1394-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 11/09/2017] [Indexed: 10/18/2022]
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20
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Zhang P, Wu L, Zhu Y, Liu M, Wang Y, Cao G, Chen XL, Tao M, Pang X. Deletion of MtrA Inhibits Cellular Development of Streptomyces coelicolor and Alters Expression of Developmental Regulatory Genes. Front Microbiol 2017; 8:2013. [PMID: 29085353 PMCID: PMC5650626 DOI: 10.3389/fmicb.2017.02013] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Accepted: 09/29/2017] [Indexed: 11/18/2022] Open
Abstract
The developmental life cycle of Streptomyces species includes aerial hyphae formation and spore maturation, two distinct developmental processes that are controlled, respectively, by two families of developmental regulatory genes, bld and whi. In this study, we show that the response regulator MtrA (SCO3013) is critical for normal development of aerial hyphae in S. coelicolor and related species. ΔmtrA, a deletion mutant of the response regulator gene mtrA, exhibited the bald phenotype typical of bld mutants defective in aerial mycelium formation, with formation either much delayed or absent depending on the culture medium. Transcriptional analysis indicated that MtrA activates multiple genes involved in formation of aerial mycelium, including chp, rdl, and ram genes, as well as developmental regulatory genes of the bld and whi families. However, the major regulatory gene bldD showed enhanced expression in ΔmtrA, suggesting it is repressed by MtrA. electrophoretic mobility shift assays indicated that MtrA binds upstream of several genes with altered expression in ΔmtrA, including bldD and whiI, and sequences similar to the consensus binding sequence for MtrA of another actinomycete, Mycobacterium tuberculosis, were found in the bound sites. A loosely conserved recognition sequence containing two short, direct repeats was identified for MtrA of S. coelicolor and was validated using mutational analysis. MtrA homologs are widely distributed among Streptomyces species, and as with S. coelicolor, deletion of the mtrA homologs sve_2757 from S. venezuelae and sli_3357 from S. lividans resulted in conditional bald morphology. Our study suggests a critical and conserved role for MtrA in Streptomyces development.
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Affiliation(s)
- Peipei Zhang
- The State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, China
| | - Lili Wu
- The State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, China
| | - Yanping Zhu
- The State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, China
| | - Meng Liu
- The State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, China
| | - Yemin Wang
- The State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai, China
| | - Guangxiang Cao
- Shandong Medicinal Biotechnology Center, Shandong Academy of Medical Sciences, Jinan, China
| | - Xiu-Lan Chen
- The State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, China
| | - Meifeng Tao
- The State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai, China
| | - Xiuhua Pang
- The State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, China
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21
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Abstract
In this article, we have described several cellular pathological effects caused by the Mycobacterium tuberculosis ESX-1. The effects include induction of necrosis, NOD2 signaling, type I interferon production, and autophagy. We then attempted to suggest that these pathological effects are mediated by the cytosolic access of M. tuberculosis-derived materials as a result of the phagosome-disrupting activity of the major ESX-1 substrate ESAT-6. Such activity of ESAT-6 is most likely due to its pore-forming activity at the membrane. The amyloidogenic characteristic of ESAT-6 is reviewed here as a potential mechanism of membrane pore formation. In addition to ESAT-6, the ESX-1 substrate EspB interferes with membrane-mediated innate immune mechanisms such as efferocytosis and autophagy, most likely through its ability to bind phospholipids. Overall, the M. tuberculosis ESX-1 secretion system appears to be a specialized system for the deployment of host membrane-targeting proteins, whose primary function is to interrupt key steps in innate immune mechanisms against pathogens. Inhibitors that block the ESX-1 system or block host factors critical for ESX-1 toxicity have been identified and should represent attractive potential new antituberculosis drugs.
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22
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Abstract
Mycobacterial 6-kDa early secreted antigenic target (ESAT-6) system (ESX) exporters transport proteins across the cytoplasmic membrane. Many proteins transported by ESX systems are then translocated across the mycobacterial cell envelope and secreted from the cell. Although the mechanism underlying protein transport across the mycolate outer membrane remains elusive, the ESX systems are closely connected with and localize to the cell envelope. Links between ESX-associated proteins, cell wall synthesis, and the maintenance of cell envelope integrity have been reported. Genes encoding the ESX systems and those required for biosynthesis of the mycobacterial envelope are coregulated. Here, we review the interplay between ESX systems and the mycobacterial cell envelope.
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Anil Kumar V, Goyal R, Bansal R, Singh N, Sevalkar RR, Kumar A, Sarkar D. EspR-dependent ESAT-6 Protein Secretion of Mycobacterium tuberculosis Requires the Presence of Virulence Regulator PhoP. J Biol Chem 2016; 291:19018-30. [PMID: 27445330 DOI: 10.1074/jbc.m116.746289] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Indexed: 01/09/2023] Open
Abstract
Attenuation of Mycobacterium bovis BCG strain is related to the loss of the RD1-encoded ESX-1 secretion system. The ESX-1 system secretes virulence factor ESAT-6 that plays a critical role in modulation of the host immune system, which is essential for establishment of a productive infection. Previous studies suggest that among the reasons for attenuation of Mycobacterium tuberculosis H37Ra is a mutation in the phoP gene that interferes with the ESX-1 secretion system and inhibits secretion of ESAT-6. Here, we identify a totally different and distinct regulatory mechanism involving PhoP and transcription regulator EspR on transcriptional control of the espACD operon, which is required for ESX-1-dependent ESAT-6 secretion. Although both of these regulators are capable of influencing espACD expression, we show that activation of espACD requires direct recruitment of both PhoP and EspR at the espACD promoter. The most fundamental insights are derived from the inhibition of EspR binding at the espACD regulatory region of the phoP mutant strain because of PhoP-EspR protein-protein interactions. Based on these results, a model is proposed suggesting how PhoP and EspR protein-protein interactions contribute to activation of espACD expression and, in turn, control ESAT-6 secretion, an essential pathogenic determinant of M. tuberculosis Together, these results have significant implications on the mechanism of virulence regulation of M. tuberculosis.
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Affiliation(s)
- Vijjamarri Anil Kumar
- From the Council of Scientific and Industrial Research-Institute of Microbial Technology, Sector 39 A, Chandigarh 160036, India
| | - Rajni Goyal
- From the Council of Scientific and Industrial Research-Institute of Microbial Technology, Sector 39 A, Chandigarh 160036, India
| | - Roohi Bansal
- From the Council of Scientific and Industrial Research-Institute of Microbial Technology, Sector 39 A, Chandigarh 160036, India
| | - Nisha Singh
- From the Council of Scientific and Industrial Research-Institute of Microbial Technology, Sector 39 A, Chandigarh 160036, India
| | - Ritesh Rajesh Sevalkar
- From the Council of Scientific and Industrial Research-Institute of Microbial Technology, Sector 39 A, Chandigarh 160036, India
| | - Ashwani Kumar
- From the Council of Scientific and Industrial Research-Institute of Microbial Technology, Sector 39 A, Chandigarh 160036, India
| | - Dibyendu Sarkar
- From the Council of Scientific and Industrial Research-Institute of Microbial Technology, Sector 39 A, Chandigarh 160036, India
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Banerjee SK, Kumar M, Alokam R, Sharma AK, Chatterjee A, Kumar R, Sahu SK, Jana K, Singh R, Yogeeswari P, Sriram D, Basu J, Kundu M. Targeting multiple response regulators of Mycobacterium tuberculosis augments the host immune response to infection. Sci Rep 2016; 6:25851. [PMID: 27181265 PMCID: PMC4867592 DOI: 10.1038/srep25851] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 04/25/2016] [Indexed: 11/06/2022] Open
Abstract
The genome of M. tuberculosis (Mtb) encodes eleven paired two component systems (TCSs) consisting of a sensor kinase (SK) and a response regulator (RR). The SKs sense environmental signals triggering RR-dependent gene expression pathways that enable the bacterium to adapt in the host milieu. We demonstrate that a conserved motif present in the C-terminal domain regulates the DNA binding functions of the OmpR family of Mtb RRs. Molecular docking studies against this motif helped to identify two molecules with a thiazolidine scaffold capable of targeting multiple RRs, and modulating their regulons to attenuate bacterial replication in macrophages. The changes in the bacterial transcriptome extended to an altered immune response with increased autophagy and NO production, leading to compromised survival of Mtb in macrophages. Our findings underscore the promise of targeting multiple RRs as a novel yet unexplored approach for development of new anti-mycobacterial agents particularly against drug-resistant Mtb.
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Affiliation(s)
- Srijon Kaushik Banerjee
- Department of Chemistry, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009, India
| | - Manish Kumar
- Department of Chemistry, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009, India
| | - Reshma Alokam
- Department of Pharmacy, Birla Institute of Technology &Science-Pilani, Hyderabad Campus, Jawahar Nagar, Hyderabad 500078, India
| | - Arun Kumar Sharma
- Department of Chemistry, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009, India
| | - Ayan Chatterjee
- Department of Chemistry, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009, India
| | - Ranjeet Kumar
- Department of Chemistry, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009, India
| | - Sanjaya Kumar Sahu
- Department of Chemistry, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009, India
| | - Kuladip Jana
- Division of Molecular Medicine, Bose Institute, P-1/12 CIT Scheme VII M, Kolkata 700054, India
| | - Ramandeep Singh
- Vaccine and Infectious Disease Research Centre, Translational Health Science and Technology Institute, NCR-Biotech Science Cluster, 3rd Milestone, Faridabad Gurgaon Expressway. Faridabad-121001, India
| | - Perumal Yogeeswari
- Department of Pharmacy, Birla Institute of Technology &Science-Pilani, Hyderabad Campus, Jawahar Nagar, Hyderabad 500078, India
| | - Dharmarajan Sriram
- Department of Pharmacy, Birla Institute of Technology &Science-Pilani, Hyderabad Campus, Jawahar Nagar, Hyderabad 500078, India
| | - Joyoti Basu
- Department of Chemistry, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009, India
| | - Manikuntala Kundu
- Department of Chemistry, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009, India
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Evolutionary landscape of the Mycobacterium tuberculosis complex from the viewpoint of PhoPR: implications for virulence regulation and application to vaccine development. mBio 2015; 6:e01289-15. [PMID: 26489860 PMCID: PMC4620462 DOI: 10.1128/mbio.01289-15] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Different members of the Mycobacterium genus have evolved to cause tuberculosis in diverse human populations and in a variety of animal species. Our cumulative knowledge of mycobacterial genomes indicates that mutations in the PhoPR two-component virulence system were acquired not only during the natural evolution of mycobacterial species but also during in vitro subculture, which has given rise to the attenuated reference strain H37Ra or to different daughter strains of Mycobacterium bovis BCG. PhoPR is a well-known regulator of pathogenic phenotypes, including secretion of the virulence factor ESAT-6, biosynthesis of acyltrehalose-based lipids, and modulation of antigen export, in members of the Mycobacterium tuberculosis complex (MTBC). Evolutionarily conserved polymorphisms in PhoPR from Mycobacterium africanum, M. bovis, or M. tuberculosis H37Ra result in loss of functional phenotypes. Interestingly, some members of the MTBC have acquired compensatory mutations to counteract these polymorphisms and, probably, to maintain their pathogenic potential. Some of these compensatory mutations include the insertion of the IS6110 element upstream from phoPR in a particular M. bovis strain that is able to transmit between humans or polymorphisms in M. africanum and M. bovis that affect the regulatory region of the espACD operon, allowing PhoPR-independent ESAT-6 secretion. This review highlights the increasing knowledge of the significance of PhoPR in the evolution of the MTBC and its potential application in the construction of new attenuated vaccines based on phoPR inactivation. In this context, the live attenuated vaccine MTBVAC, based on a phoP fadD26 deletion mutant of M. tuberculosis, is the first vaccine of this kind to successfully enter into clinical development, representing a historic milestone in the field of human vaccinology.
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The Carbonic Anhydrase Inhibitor Ethoxzolamide Inhibits the Mycobacterium tuberculosis PhoPR Regulon and Esx-1 Secretion and Attenuates Virulence. Antimicrob Agents Chemother 2015; 59:4436-45. [PMID: 25987613 DOI: 10.1128/aac.00719-15] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 05/07/2015] [Indexed: 02/03/2023] Open
Abstract
Mycobacterium tuberculosis must sense and adapt to host environmental cues to establish and maintain an infection. The two-component regulatory system PhoPR plays a central role in sensing and responding to acidic pH within the macrophage and is required for M. tuberculosis intracellular replication and growth in vivo. Therefore, the isolation of compounds that inhibit PhoPR-dependent adaptation may identify new antivirulence therapies to treat tuberculosis. Here, we report that the carbonic anhydrase inhibitor ethoxzolamide inhibits the PhoPR regulon and reduces pathogen virulence. We show that treatment of M. tuberculosis with ethoxzolamide recapitulates phoPR mutant phenotypes, including downregulation of the core PhoPR regulon, altered accumulation of virulence-associated lipids, and inhibition of Esx-1 protein secretion. Quantitative single-cell imaging of a PhoPR-dependent fluorescent reporter strain demonstrates that ethoxzolamide inhibits PhoPR-regulated genes in infected macrophages and mouse lungs. Moreover, ethoxzolamide reduces M. tuberculosis growth in both macrophages and infected mice. Ethoxzolamide inhibits M. tuberculosis carbonic anhydrase activity, supporting a previously unrecognized link between carbonic anhydrase activity and PhoPR signaling. We propose that ethoxzolamide may be pursued as a new class of antivirulence therapy that functions by modulating expression of the PhoPR regulon and Esx-1-dependent virulence.
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