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Nobs E, Laschanzky K, Munke K, Movert E, Valfridsson C, Carlsson F. Cytosolic serpins act in a cytoprotective feedback loop that limits ESX-1-dependent death of Mycobacterium marinum-infected macrophages. mBio 2024:e0038424. [PMID: 39087767 DOI: 10.1128/mbio.00384-24] [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: 02/06/2024] [Accepted: 05/28/2024] [Indexed: 08/02/2024] Open
Abstract
Serine protease inhibitors (serpins) constitute the largest family of protease inhibitors expressed in humans, but their role in infection remains largely unexplored. In infected macrophages, the mycobacterial ESX-1 type VII secretion system permeabilizes internal host membranes and causes leakage into the cytosol of host DNA, which induces type I interferon (IFN) production via the cyclic GMP-AMP synthase (cGAS) and stimulator of IFN genes (STING) surveillance pathway, and promotes infection in vivo. Using the Mycobacterium marinum infection model, we show that ESX-1-mediated type I IFN signaling in macrophages selectively induces the expression of serpina3f and serpina3g, two cytosolic serpins of the clade A3. The membranolytic activity of ESX-1 also caused leakage of cathepsin B into the cytosol where it promoted cell death, suggesting that the induction of type I IFN comes at the cost of lysosomal rupture and toxicity. However, the production of cytosolic serpins suppressed the protease activity of cathepsin B in this compartment and thus limited cell death, a function that was associated with increased bacterial growth in infected mice. These results suggest that cytosolic serpins act in a type I IFN-dependent cytoprotective feedback loop to counteract the inevitable toxic effect of ESX-1-mediated host membrane rupture. IMPORTANCE The ESX-1 type VII secretion system is a key virulence determinant of pathogenic mycobacteria. The ability to permeabilize host cell membranes is critical for several ESX-1-dependent virulence traits, including phagosomal escape and induction of the type I interferon (IFN) response. We find that it comes at the cost of lysosomal leakage and subsequent host cell death. However, our results suggest that ESX-1-mediated type I IFN signaling selectively upregulates serpina3f and serpina3g and that these cytosolic serpins limit cell death caused by cathepsin B that has leaked into the cytosol, a function that is associated with increased bacterial growth in vivo. The ability to rupture host membranes is widespread among bacterial pathogens, and it will be of interest to evaluate the role of cytosolic serpins and this type I IFN-dependent cytoprotective feedback loop in the context of human infection.
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Affiliation(s)
- Esther Nobs
- Department of Biology, Lund University, Lund, Sweden
| | | | - Kristina Munke
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Elin Movert
- Department of Biology, Lund University, Lund, Sweden
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Singh S, Kanzin D, Chavez S, Saavedra-Avila NA, Ng TW, Lukose R, Mayer O, Kim J, Chen B, Chen M, Porcelli SA, Jacobs WR, Tiwari S. Boosting Immunogenicity of a Recombinant Mycobacterium smegmatis Strain via Zinc-Dependent Ribosomal Proteins. Biomedicines 2024; 12:1571. [PMID: 39062144 PMCID: PMC11274837 DOI: 10.3390/biomedicines12071571] [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: 05/10/2024] [Revised: 06/18/2024] [Accepted: 06/23/2024] [Indexed: 07/28/2024] Open
Abstract
Tuberculosis (TB) continues to be a major global health burden and kills over a million people annually. New immunization strategies are required for the development of an efficacious TB vaccine that can potentially induce sterilizing immunity. In this study, we first confirmed that a live vaccine strain of Mycobacterium smegmatis, previously designated as IKEPLUS, conferred a higher survival benefit than the Bacillus Calmette-Guerin (BCG) in a murine model of intravenous Mycobacterium tuberculosis (Mtb) infection. We have shown that there was a significant increase in the expression of the Rv0282 gene, which is encoded in the esx-3 locus, which played an important role in iron uptake when IKEPLUS was grown in both low zinc and iron-containing Sauton medium. We then confirmed using in vitro assays of biofilm formation that zinc plays a vital role in the growth and formation of M. smegmatis biofilms. IKEPLUS grown in low zinc media led to the better protection of mice after intravenous challenge with a very high dosage of Mtb. We also showed that various variants of IKEPLUS induced apoptotic cell-death of infected macrophages at a higher rate than wild-type M. smegmatis. We next attempted to determine if zinc containing ribosomal proteins such as rpmb2 could contribute to protective efficacy against Mtb infection. Since BCG has an established role in anti-mycobacterial efficacy, we boosted BCG vaccinated mice with rmpb2, but this did not lead to an increment in the protection mediated by BCG.
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Affiliation(s)
- Shivani Singh
- Department of Microbiology & Immunology, Albert Einstein College of Medicine, New York, NY 10461, USA
- Department of Medicine, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - David Kanzin
- Department of Biological Sciences and Border Biomedical Research Center, University of Texas, El Paso, TX 79968, USA
| | - Sarah Chavez
- Department of Biological Sciences and Border Biomedical Research Center, University of Texas, El Paso, TX 79968, USA
| | | | - Tony W. Ng
- Department of Microbiology & Immunology, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - Regy Lukose
- Department of Microbiology & Immunology, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - Oren Mayer
- Department of Microbiology & Immunology, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - John Kim
- Department of Microbiology & Immunology, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - Bing Chen
- Department of Microbiology & Immunology, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - Mei Chen
- Department of Microbiology & Immunology, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - Steven A. Porcelli
- Department of Microbiology & Immunology, Albert Einstein College of Medicine, New York, NY 10461, USA
- Department of Medicine, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - William R. Jacobs
- Department of Microbiology & Immunology, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - Sangeeta Tiwari
- Department of Biological Sciences and Border Biomedical Research Center, University of Texas, El Paso, TX 79968, USA
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Jones BS, Pareek V, Hu DD, Weaver SD, Syska C, Galfano G, Champion MM, Champion PA. N - acetyl-transferases required for iron uptake and aminoglycoside resistance promote virulence lipid production in M. marinum. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.05.602253. [PMID: 39005365 PMCID: PMC11245092 DOI: 10.1101/2024.07.05.602253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
Phagosomal lysis is a key aspect of mycobacterial infection of host macrophages. Acetylation is a protein modification mediated enzymatically by N-acetyltransferases (NATs) that impacts bacterial pathogenesis and physiology. To identify NATs required for lytic activity, we leveraged Mycobacterium marinum, a nontubercular pathogen and an established model for M. tuberculosis. M. marinum hemolysis is a proxy for phagolytic activity. We generated M. marinum strains with deletions in conserved NAT genes and screened for hemolytic activity. Several conserved lysine acetyltransferases (KATs) contributed to hemolysis. Hemolysis is mediated by the ESX-1 secretion system and by phthiocerol dimycocerosate (PDIM), a virulence lipid. For several strains, the hemolytic activity was restored by the addition of second copy of the ESX-1 locus. Using thin-layer chromatography (TLC), we found a single NAT required for PDIM and phenolic glycolipid (PGL) production. MbtK is a conserved KAT required for mycobactin siderophore synthesis and virulence. Mycobactin J exogenously complemented PDIM/PGL production in the Δ mbtK strain. The Δ mbtK M. marinum strain was attenuated in macrophage and Galleria mellonella infection models. Constitutive expression of either eis or papA5, which encode a KAT required for aminoglycoside resistance and a PDIM/PGL biosynthetic enzyme, rescued PDIM/PGL production and virulence of the Δ mbtK strain. Eis N-terminally acetylated PapA5 in vitro , supporting a mechanism for restored lipid production. Overall, our study establishes connections between the MbtK and Eis NATs, and between iron uptake and PDIM and PGL synthesis in M. marinum . Our findings underscore the multifunctional nature of mycobacterial NATs and their connection to key virulence pathways. Significance Statement Acetylation is a modification of protein N-termini, lysine residues, antibiotics and lipids. Many of the enzymes that promote acetylation belong to the GNAT family of proteins. M. marinum is a well-established as a model to understand how M. tuberculosis causes tuberculosis. In this study we sought to identify conserved GNAT proteins required for early stages of mycobacterial infection. Using M. marinum, we determined that several GNAT proteins are required for the lytic activity of M. marinum. We uncovered previously unknown connections between acetyl-transferases required for iron uptake and antimicrobial resistance, and the production of the unique mycobacterial lipids, PDIM and PGLOur data support that acetyl-transferases from the GNAT family are interconnected, and have activities beyond those previously reported.
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Miles JR, Lu P, Bai S, Aguillón-Durán GP, Rodríguez-Herrera JE, Gunn BM, Restrepo BI, Lu LL. Antigen specificity shapes antibody functions in tuberculosis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.03.597169. [PMID: 38895452 PMCID: PMC11185737 DOI: 10.1101/2024.06.03.597169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
Tuberculosis (TB) is the number one infectious disease cause of death worldwide due to an incomplete understanding of immunity. Emerging data highlight antibody functions mediated by the Fc domain as immune correlates. However, the mechanisms by which antibody functions impact the causative agent Mycobacterium tuberculosis (Mtb) are unclear. Here, we examine how antigen specificity determined by the Fab domain shapes Fc effector functions against Mtb. Using the critical structural and secreted virulence proteins Mtb cell wall and ESAT-6 & CFP-10, we observe that antigen specificity alters subclass, antibody post-translational glycosylation, and Fc effector functions in TB patients. Moreover, Mtb cell wall IgG3 enhances disease through opsonophagocytosis of extracellular Mtb . In contrast, polyclonal and a human monoclonal IgG1 we generated targeting ESAT-6 & CFP-10 inhibit intracellular Mtb . These data show that antibodies have multiple roles in TB and antigen specificity is a critical determinant of the protective and pathogenic capacity.
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Garrett SR, Higginson AB, Palmer T. Multiple variants of the type VII secretion system in Gram-positive bacteria. MICROLIFE 2024; 5:uqae013. [PMID: 38957458 PMCID: PMC11217815 DOI: 10.1093/femsml/uqae013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 05/08/2024] [Accepted: 06/04/2024] [Indexed: 07/04/2024]
Abstract
Type VII secretion systems (T7SS) are found in bacteria across the Bacillota and Actinomycetota phyla and have been well described in Staphylococcus aureus, Bacillus subtilis, and pathogenic mycobacteria. The T7SS from Actinomycetota and Bacillota share two common components, a membrane-bound EccC/EssC ATPase and EsxA, a small helical hairpin protein of the WXG100 family. However, they also have additional phylum-specific components, and as a result they are termed the T7SSa (Actinomycetota) and T7SSb (Bacillota), respectively. Here, we identify additional organizations of the T7SS across these two phyla and describe eight additional T7SS subtypes, which we have named T7SSc-T7SSj. T7SSd is found exclusively in Actinomycetota including the Olselnella and Bifodobacterium genus, whereas the other seven are found only in Bacillota. All of the novel subtypes contain the canonical ATPase (TsxC) and the WXG100-family protein (TsxA). Most of them also contain a small ubiquitin-related protein, TsxB, related to the T7SSb EsaB/YukD component. Protein kinases, phosphatases, and forkhead-associated (FHA) proteins are often encoded in the novel T7SS gene clusters. Candidate substrates of these novel T7SS subtypes include LXG-domain and RHS proteins. Predicted substrates are frequently encoded alongside genes for additional small WXG100-related proteins that we speculate serve as cosecretion partners. Collectively our findings reveal unexpected diversity in the T7SS in Gram-positive bacteria.
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Affiliation(s)
- Stephen R Garrett
- Newcastle University Biosciences Institute, Medical School, Framlington Place, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Andrew B Higginson
- Newcastle University Biosciences Institute, Medical School, Framlington Place, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Tracy Palmer
- Newcastle University Biosciences Institute, Medical School, Framlington Place, Newcastle upon Tyne NE2 4HH, United Kingdom
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Jones BS, Hu DD, Nicholson KR, Cronin RM, Weaver SD, Champion MM, Champion PA. The loss of the PDIM/PGL virulence lipids causes differential secretion of ESX-1 substrates in Mycobacterium marinum. mSphere 2024; 9:e0000524. [PMID: 38661343 PMCID: PMC11237470 DOI: 10.1128/msphere.00005-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 03/21/2024] [Indexed: 04/26/2024] Open
Abstract
The mycobacterial cell envelope is a major virulence determinant in pathogenic mycobacteria. Specific outer lipids play roles in pathogenesis, modulating the immune system and promoting the secretion of virulence factors. ESX-1 (ESAT-6 system-1) is a conserved protein secretion system required for mycobacterial pathogenesis. Previous studies revealed that mycobacterial strains lacking the outer lipid PDIM have impaired ESX-1 function during laboratory growth and infection. The mechanisms underlying changes in ESX-1 function are unknown. We used a proteo-genetic approach to measure phthiocerol dimycocerosate (PDIM)- and phenolic glycolipid (PGL)-dependent protein secretion in M. marinum, a non-tubercular mycobacterial pathogen that causes tuberculosis-like disease in ectothermic animals. Importantly, M. marinum is a well-established model for mycobacterial pathogenesis. Our findings showed that M. marinum strains without PDIM and PGL showed specific, significant reductions in protein secretion compared to the WT and complemented strains. We recently established a hierarchy for the secretion of ESX-1 substrates in four (I-IV) groups. Loss of PDIM differentially impacted secretion of Group III and IV ESX-1 substrates, which are likely the effectors of pathogenesis. Our data suggest that the altered secretion of specific ESX-1 substrates is responsible for the observed ESX-1-related effects in PDIM-deficient strains.IMPORTANCEMycobacterium tuberculosis, the cause of human tuberculosis, killed an estimated 1.3 million people in 2022. Non-tubercular mycobacterial species cause acute and chronic human infections. Understanding how these bacteria cause disease is critical. Lipids in the cell envelope are essential for mycobacteria to interact with the host and promote disease. Strains lacking outer lipids are attenuated for infection, but the reasons are unclear. Our research aims to identify a mechanism for attenuation of mycobacterial strains without the PDIM and PGL outer lipids in M. marinum. These findings will enhance our understanding of the importance of lipids in pathogenesis and how these lipids contribute to other established virulence mechanisms.
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Affiliation(s)
- Bradley S. Jones
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, USA
| | - Daniel D. Hu
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Kathleen R. Nicholson
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Rachel M. Cronin
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Simon D. Weaver
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Matthew M. Champion
- 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
| | - Patricia A. Champion
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana, USA
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7
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Banerjee A, Chakraborty M, Sharma S, Chaturvedi R, Bose A, Biswas P, Singh A, Visweswariah SS. Cyclic AMP binding to a universal stress protein in Mycobacterium tuberculosis is essential for viability. J Biol Chem 2024; 300:107287. [PMID: 38636658 PMCID: PMC11107214 DOI: 10.1016/j.jbc.2024.107287] [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: 03/18/2024] [Revised: 04/04/2024] [Accepted: 04/05/2024] [Indexed: 04/20/2024] Open
Abstract
Mycobacterial genomes encode multiple adenylyl cyclases and cAMP effector proteins, underscoring the diverse ways these bacteria utilize cAMP. We identified universal stress proteins, Rv1636 and MSMEG_3811 in Mycobacterium tuberculosis and Mycobacterium smegmatis, respectively, as abundantly expressed, novel cAMP-binding proteins. Rv1636 is secreted via the SecA2 secretion system in M. tuberculosis but is not directly responsible for the efflux of cAMP from the cell. In slow-growing mycobacteria, intrabacterial concentrations of Rv1636 were equivalent to the concentrations of cAMP present in the cell. In contrast, levels of intrabacterial MSMEG_3811 in M. smegmatis were lower than that of cAMP and therefore, overexpression of Rv1636 increased levels of "bound" cAMP. While msmeg_3811 could be readily deleted from the genome of M. smegmatis, we found that the rv1636 gene is essential for the viability of M. tuberculosis and is dependent on the cAMP-binding ability of Rv1636. Therefore, Rv1636 may function to regulate cAMP signaling by direct sequestration of the second messenger. This is the first evidence of a "sponge" for any second messenger in bacterial signaling that would allow mycobacterial cells to regulate the available intrabacterial "free" pool of cAMP.
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Affiliation(s)
- Arka Banerjee
- Department of Developmental Biology and Genetics, Indian Institute of Science, Bengaluru, India
| | - Moubani Chakraborty
- Department of Developmental Biology and Genetics, Indian Institute of Science, Bengaluru, India
| | - Suruchi Sharma
- Department of Developmental Biology and Genetics, Indian Institute of Science, Bengaluru, India
| | - Ruchi Chaturvedi
- Department of Microbiology and Cell Biology, Centre for Infectious Disease Research, Indian Institute of Science, Bengaluru, India
| | - Avipsa Bose
- Department of Developmental Biology and Genetics, Indian Institute of Science, Bengaluru, India
| | - Priyanka Biswas
- Department of Developmental Biology and Genetics, Indian Institute of Science, Bengaluru, India
| | - Amit Singh
- Department of Microbiology and Cell Biology, Centre for Infectious Disease Research, Indian Institute of Science, Bengaluru, India
| | - Sandhya S Visweswariah
- Department of Developmental Biology and Genetics, Indian Institute of Science, Bengaluru, India.
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8
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Zheng W, Borja M, Dorman L, Liu J, Zhou A, Seng A, Arjyal R, Sunshine S, Nalyvayko A, Pisco A, Rosenberg O, Neff N, Zha BS. How Mycobacterium tuberculosis builds a home: Single-cell analysis reveals M. tuberculosis ESX-1-mediated accumulation of anti-inflammatory macrophages in infected mouse lungs. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.20.590421. [PMID: 38712150 PMCID: PMC11071417 DOI: 10.1101/2024.04.20.590421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Mycobacterium tuberculosis (MTB) infects and replicates in lung mononuclear phagocytes (MNPs) with astounding ability to evade elimination. ESX-1, a type VII secretion system, acts as a virulence determinant that contributes to MTB's ability to survive within MNPs, but its effect on MNP recruitment and/or differentiation remains unknown. Here, using single-cell RNA sequencing, we studied the role of ESX-1 in MNP heterogeneity and response in mice and murine bone marrow-derived macrophages (BMDM). We found that ESX-1 is required for MTB to recruit diverse MNP subsets with high MTB burden. Further, MTB induces an anti-inflammatory signature in MNPs and BMDM in an ESX-1 dependent manner. Similarly, spatial transcriptomics revealed an upregulation of anti-inflammatory signals in MTB lesions, where monocyte-derived macrophages concentrate near MTB-infected cells. Together, our findings suggest that MTB ESX-1 mediates the recruitment and differentiation of anti-inflammatory MNPs, which MTB can infect and manipulate for survival.
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9
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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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10
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Ma M, Duan Y, Peng C, Wu Y, Zhang X, Chang B, Wang F, Yang H, Zheng R, Cheng H, Cheng Y, He Y, Huang J, Lei J, Ma H, Li L, Wang J, Huang X, Tang F, Liu J, Li J, Ying R, Wang P, Sha W, Gao Y, Wang L, Ge B. Mycobacterium tuberculosis inhibits METTL14-mediated m 6A methylation of Nox2 mRNA and suppresses anti-TB immunity. Cell Discov 2024; 10:36. [PMID: 38548762 PMCID: PMC10978938 DOI: 10.1038/s41421-024-00653-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2023] [Accepted: 01/29/2024] [Indexed: 04/01/2024] Open
Abstract
Internal N6-methyladenosine (m6A) modifications are among the most abundant modifications of messenger RNA, playing a critical role in diverse biological and pathological processes. However, the functional role and regulatory mechanism of m6A modifications in the immune response to Mycobacterium tuberculosis infection remains unknown. Here, we report that methyltransferase-like 14 (METTL14)-dependent m6A methylation of NAPDH oxidase 2 (Nox2) mRNA was crucial for the host immune defense against M. tuberculosis infection and that M. tuberculosis-secreted antigen EsxB (Rv3874) inhibited METTL14-dependent m6A methylation of Nox2 mRNA. Mechanistically, EsxB interacted with p38 MAP kinase and disrupted the association of TAB1 with p38, thus inhibiting the TAB1-mediated autophosphorylation of p38. Interaction of EsxB with p38 also impeded the binding of p38 with METTL14, thereby inhibiting the p38-mediated phosphorylation of METTL14 at Thr72. Inhibition of p38 by EsxB restrained liquid-liquid phase separation (LLPS) of METTL14 and its subsequent interaction with METTL3, preventing the m6A modification of Nox2 mRNA and its association with the m6A-binding protein IGF2BP1 to destabilize Nox2 mRNA, reduce ROS levels, and increase intracellular survival of M. tuberculosis. Moreover, deletion or mutation of the phosphorylation site on METTL14 impaired the inhibition of ROS level by EsxB and increased bacterial burden or histological damage in the lungs during infection in mice. These findings identify a previously unknown mechanism that M. tuberculosis employs to suppress host immunity, providing insights that may empower the development of effective immunomodulators that target M. tuberculosis.
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Affiliation(s)
- Mingtong Ma
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Key Laboratory of Pathogen-Host Interaction, Ministry of Education, Tongji University School of Medicine, Shanghai, China
- Department of Microbiology and Immunology, Tongji University School of Medicine, Shanghai, China
| | - Yongjia Duan
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Key Laboratory of Pathogen-Host Interaction, Ministry of Education, Tongji University School of Medicine, Shanghai, China
- Department of Microbiology and Immunology, Tongji University School of Medicine, Shanghai, China
| | - Cheng Peng
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Key Laboratory of Pathogen-Host Interaction, Ministry of Education, Tongji University School of Medicine, Shanghai, China
- Department of Microbiology and Immunology, Tongji University School of Medicine, Shanghai, China
| | - You Wu
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Xinning Zhang
- State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Peking University, Beijing, China
| | - Boran Chang
- State Key Laboratory of Cell Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Fei Wang
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Key Laboratory of Pathogen-Host Interaction, Ministry of Education, Tongji University School of Medicine, Shanghai, China
- Department of Microbiology and Immunology, Tongji University School of Medicine, Shanghai, China
| | - Hua Yang
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Key Laboratory of Pathogen-Host Interaction, Ministry of Education, Tongji University School of Medicine, Shanghai, China
| | - Ruijuan Zheng
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Key Laboratory of Pathogen-Host Interaction, Ministry of Education, Tongji University School of Medicine, Shanghai, China
| | - Hongyu Cheng
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Key Laboratory of Pathogen-Host Interaction, Ministry of Education, Tongji University School of Medicine, Shanghai, China
- Department of Microbiology and Immunology, Tongji University School of Medicine, Shanghai, China
| | - Yuanna Cheng
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Key Laboratory of Pathogen-Host Interaction, Ministry of Education, Tongji University School of Medicine, Shanghai, China
- Department of Microbiology and Immunology, Tongji University School of Medicine, Shanghai, China
| | - Yifan He
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Key Laboratory of Pathogen-Host Interaction, Ministry of Education, Tongji University School of Medicine, Shanghai, China
- Department of Microbiology and Immunology, Tongji University School of Medicine, Shanghai, China
| | - Jingping Huang
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Key Laboratory of Pathogen-Host Interaction, Ministry of Education, Tongji University School of Medicine, Shanghai, China
- Department of Microbiology and Immunology, Tongji University School of Medicine, Shanghai, China
| | - Jinming Lei
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Key Laboratory of Pathogen-Host Interaction, Ministry of Education, Tongji University School of Medicine, Shanghai, China
- Department of Microbiology and Immunology, Tongji University School of Medicine, Shanghai, China
| | - Hanyu Ma
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Key Laboratory of Pathogen-Host Interaction, Ministry of Education, Tongji University School of Medicine, Shanghai, China
- Department of Microbiology and Immunology, Tongji University School of Medicine, Shanghai, China
| | - Liru Li
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Key Laboratory of Pathogen-Host Interaction, Ministry of Education, Tongji University School of Medicine, Shanghai, China
- Department of Microbiology and Immunology, Tongji University School of Medicine, Shanghai, China
| | - Jie Wang
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Key Laboratory of Pathogen-Host Interaction, Ministry of Education, Tongji University School of Medicine, Shanghai, China
| | - Xiaochen Huang
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Key Laboratory of Pathogen-Host Interaction, Ministry of Education, Tongji University School of Medicine, Shanghai, China
| | - Fen Tang
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Key Laboratory of Pathogen-Host Interaction, Ministry of Education, Tongji University School of Medicine, Shanghai, China
- Department of Microbiology and Immunology, Tongji University School of Medicine, Shanghai, China
| | - Jun Liu
- State Key Laboratory of Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Peking University, Beijing, China
| | - Jinsong Li
- State Key Laboratory of Cell Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Ruoyan Ying
- Clinic and Research Center of Tuberculosis, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Peng Wang
- Clinic and Research Center of Tuberculosis, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Wei Sha
- Clinic and Research Center of Tuberculosis, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Yawei Gao
- Institute for Regenerative Medicine, Shanghai East Hospital, Shanghai Key Laboratory of Signaling and Disease Research, School of Life Sciences and Technology, Tongji University, Shanghai, China.
| | - Lin Wang
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Key Laboratory of Pathogen-Host Interaction, Ministry of Education, Tongji University School of Medicine, Shanghai, China.
- Department of Microbiology and Immunology, Tongji University School of Medicine, Shanghai, China.
| | - Baoxue Ge
- Shanghai Key Laboratory of Tuberculosis, Shanghai Pulmonary Hospital, Key Laboratory of Pathogen-Host Interaction, Ministry of Education, Tongji University School of Medicine, Shanghai, China.
- Department of Microbiology and Immunology, Tongji University School of Medicine, Shanghai, China.
- Clinical Translation Research Center, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China.
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11
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Malik AA, Shariq M, Sheikh JA, Zarin S, Ahuja Y, Fayaz H, Alam A, Ehtesham NZ, Hasnain SE. Activation of the lysosomal damage response and selective autophagy: the coordinated actions of galectins, TRIM proteins, and CGAS-STING1 in providing immunity against Mycobacterium tuberculosis. Crit Rev Microbiol 2024:1-20. [PMID: 38470107 DOI: 10.1080/1040841x.2024.2321494] [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: 08/04/2023] [Accepted: 02/14/2024] [Indexed: 03/13/2024]
Abstract
Autophagy is a crucial immune defense mechanism that controls the survival and pathogenesis of M. tb by maintaining cell physiology during stress and pathogen attack. The E3-Ub ligases (PRKN, SMURF1, and NEDD4) and autophagy receptors (SQSTM1, TAX1BP1, CALCOCO2, OPTN, and NBR1) play key roles in this process. Galectins (LGALSs), which bind to sugars and are involved in identifying damaged cell membranes caused by intracellular pathogens such as M. tb, are essential. These include LGALS3, LGALS8, and LGALS9, which respond to endomembrane damage and regulate endomembrane damage caused by toxic chemicals, protein aggregates, and intracellular pathogens, including M. tb. They also activate selective autophagy and de novo endolysosome biogenesis. LGALS3, LGALS9, and LGALS8 interact with various components to activate autophagy and repair damage, while CGAS-STING1 plays a critical role in providing immunity against M. tb by activating selective autophagy and producing type I IFNs with antimycobacterial functions. STING1 activates cGAMP-dependent autophagy which provides immunity against various pathogens. Additionally, cytoplasmic surveillance pathways activated by ds-DNA, such as inflammasomes mediated by NLRP3 and AIM2 complexes, control M. tb. Modulation of E3-Ub ligases with small regulatory molecules of LGALSs and TRIM proteins could be a novel host-based therapeutic approach for controlling TB.
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Affiliation(s)
- Asrar Ahmad Malik
- Department of Life Sciences, School of Basic Sciences and Research, Sharda University, Greater Noida, Uttar Pradesh, India
| | - Mohd Shariq
- ICMR-National Institute of Pathology, New Delhi, India
| | - Javaid Ahmad Sheikh
- Department of Biotechnology, School of Chemical and Life Sciences, New Delhi, India
| | - Sheeba Zarin
- Department of Life Sciences, School of Basic Sciences and Research, Sharda University, Greater Noida, Uttar Pradesh, India
- Department of Molecular Medicine, School of Interdisciplinary Sciences and Technology, New Delhi, India
| | - Yashika Ahuja
- Department of Life Sciences, School of Basic Sciences and Research, Sharda University, Greater Noida, Uttar Pradesh, India
| | - Haleema Fayaz
- Department of Life Sciences, School of Basic Sciences and Research, Sharda University, Greater Noida, Uttar Pradesh, India
| | - Anwar Alam
- Department of Biotechnology, School of Science and Engineering Technology, Sharda University, Greater Noida, India
| | - Nasreen Z Ehtesham
- Department of Life Sciences, School of Basic Sciences and Research, Sharda University, Greater Noida, Uttar Pradesh, India
| | - Seyed E Hasnain
- Department of Life Sciences, School of Basic Sciences and Research, Sharda University, Greater Noida, Uttar Pradesh, India
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology, New Delhi, India
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12
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Serene LG, Webber K, Champion PA, Schorey JS. Mycobacterium tuberculosis SecA2-dependent activation of host Rig-I/MAVs signaling is not conserved in Mycobacterium marinum. PLoS One 2024; 19:e0281564. [PMID: 38394154 PMCID: PMC10889897 DOI: 10.1371/journal.pone.0281564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 11/02/2023] [Indexed: 02/25/2024] Open
Abstract
Retinoic acid inducible gene I (Rig-I) is a cytosolic pattern recognition receptor canonically described for its important role in sensing viral RNAs. Increasingly, bacterially-derived RNA from intracellular bacteria such as Mycobacterium tuberculosis, have been shown to activate the same host Rig-I/Mitochondrial antiviral sensing protein (MAVS) signaling pathway to drive a type-I interferon response that contributes to bacterial pathogenesis in vivo. In M. tuberculosis, this response is mediated by the protein secretion system SecA2, but little is known about whether this process is conserved in other pathogenic mycobacteria or the mechanism by which these nucleic acids gain access to the host cytoplasm. Because the M. tuberculosis and M. marinum SecA2 protein secretion systems share a high degree of genetic and functional conservation, we hypothesized that Rig-I/MAVS activation and subsequent induction of IFN-β secretion by host macrophages will also be conserved between these two mycobacterial species. To test this, we generated a ΔsecA2 M. marinum strain along with complementation strains expressing either the M. marinum or M. tuberculosis secA2 genes. Our results suggest that the ΔsecA2 strain has a growth defect in vitro but not in host macrophages. These intracellular growth curves also suggested that the calculation applied to estimate the number of bacteria added to macrophage monolayers in infection assays underestimates bacterial inputs for the ΔsecA2 strain. Therefore, to better examine secreted IFN-β levels when bacterial infection levels are equal across strains we plated bacterial CFUs at 2hpi alongside our ELISA based infections. This enabled us to normalize secreted levels of IFN-β to a standard number of bacteria. Applying this approach to both WT and MAVS-/- bone marrow derived macrophages we observed equal or higher levels of secreted IFN-β from macrophages infected with the ΔsecA2 M. marinum strain as compared to WT. Together our findings suggest that activation of host Rig-I/MAVS cytosolic sensors and subsequent induction of IFN-β response in a SecA2-dependent manner is not conserved in M. marinum under the conditions tested.
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Affiliation(s)
- Lindsay G. Serene
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, United States of America
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, United States of America
| | - Kylie Webber
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, United States of America
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, United States of America
| | - Patricia A. Champion
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, United States of America
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, United States of America
| | - Jeffrey S. Schorey
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, United States of America
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, United States of America
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13
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Ramamoorthy S, Pena M, Ghosh P, Liao YY, Paret M, Jones JB, Potnis N. Transcriptome profiling of type VI secretion system core gene tssM mutant of Xanthomonas perforans highlights regulators controlling diverse functions ranging from virulence to metabolism. Microbiol Spectr 2024; 12:e0285223. [PMID: 38018859 PMCID: PMC10782981 DOI: 10.1128/spectrum.02852-23] [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: 07/14/2023] [Accepted: 10/20/2023] [Indexed: 11/30/2023] Open
Abstract
IMPORTANCE T6SS has received attention due to its significance in mediating interorganismal competition through contact-dependent release of effector molecules into prokaryotic and eukaryotic cells. Reverse-genetic studies have indicated the role of T6SS in virulence in a variety of plant pathogenic bacteria, including the one studied here, Xanthomonas. However, it is not clear whether such effect on virulence is merely due to a shift in the microbiome-mediated protection or if T6SS is involved in a complex virulence regulatory network. In this study, we conducted in vitro transcriptome profiling in minimal medium to decipher the signaling pathways regulated by tssM-i3* in X. perforans AL65. We show that TssM-i3* regulates the expression of a suite of genes associated with virulence and metabolism either directly or indirectly by altering the transcription of several regulators. These findings further expand our knowledge on the intricate molecular circuits regulated by T6SS in phytopathogenic bacteria.
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Affiliation(s)
- Sivakumar Ramamoorthy
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| | - Michelle Pena
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| | - Palash Ghosh
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
| | - Ying-Yu Liao
- Department of Plant Pathology, University of Florida, Gainesville, Florida, USA
| | - Mathews Paret
- Department of Plant Pathology, University of Florida, Gainesville, Florida, USA
| | - Jeffrey B. Jones
- Department of Plant Pathology, University of Florida, Gainesville, Florida, USA
| | - Neha Potnis
- Department of Entomology and Plant Pathology, Auburn University, Auburn, Alabama, USA
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14
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Singh S, Kanzin D, Chavez S, Saavedra-Avila NA, Ng TW, Lukose R, Mayer O, Kim J, Chen B, Chen M, Porcelli SA, Jacobs WR, Tiwari S. Boosting bactericidal immunity of a recombinant Mycobacterium smegmatis strain via zinc-dependent ribosomal proteins. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.11.571163. [PMID: 38168334 PMCID: PMC10760040 DOI: 10.1101/2023.12.11.571163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Tuberculosis (TB) continues to be a major global health burden and kills over a million people annually. New immunization strategies are required for the development of an efficacious TB vaccine that can potentially induce sterilizing immunity. In this study, we first confirmed that various strains of the IKEPLUS vaccine confer a higher survival benefit than BCG in a murine model of intravenous Mycobacterium tuberculosis (Mtb) infection. We have shown that there was a significant increase in the expression of the Rv0282 when IKEPLUS was grown in low zinc and iron containing Sauton medium. We confirmed on biofilm assays that zinc plays a vital role in the growth and formation of Mycobacterium smegmatis ( M. smegmatis ) biofilms. IKEPLUS grown in low zinc media led to better protection of mice after intravenous challenge with very high dosage of Mtb. We also showed that various variants of IKEPLUS induced apoptotic cell-death of infected macrophages at a higher rate than wild type M. smegmatis . We next attempted to determine if zinc containing ribosomal proteins such as rpmb2 could contribute to protective efficacy against Mtb infection. Since BCG has an established role in anti-mycobacterial efficacy, we boosted BCG vaccinated mice with rmpb2 but this did not lead to an increment in the protection mediated by BCG.
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15
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Boardman ER, Palmer T, Alcock F. Interbacterial competition mediated by the type VIIb secretion system. MICROBIOLOGY (READING, ENGLAND) 2023; 169:001420. [PMID: 38116759 PMCID: PMC10765036 DOI: 10.1099/mic.0.001420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Accepted: 12/06/2023] [Indexed: 12/21/2023]
Abstract
Successful occupancy of a given niche requires the colonising bacteria to interact extensively with the biotic and abiotic environment, including other resident microbes. Bacteria have evolved a range of protein secretion machines for this purpose with eleven such systems identified to date. The type VIIb secretion system (T7SSb) is utilised by Bacillota to secrete a range of protein substrates, including antibacterial toxins targeting closely related strains, and the system as a whole has been implicated in a range of activities such as iron acquisition, intercellular signalling, host colonisation and virulence. This review covers the components and secretion mechanism of the T7SSb, the substrates of these systems and their roles in Gram-positive bacteria, with a focus on interbacterial competition.
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Affiliation(s)
- Eleanor R. Boardman
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Tracy Palmer
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Felicity Alcock
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
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16
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Yang Y, Boardman E, Deme J, Alcock F, Lea S, Palmer T. Three small partner proteins facilitate the type VII-dependent secretion of an antibacterial nuclease. mBio 2023; 14:e0210023. [PMID: 37815362 PMCID: PMC10653861 DOI: 10.1128/mbio.02100-23] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 08/23/2023] [Indexed: 10/11/2023] Open
Abstract
IMPORTANCE Staphylococcus aureus is an opportunistic human pathogen associated with severe infections and antimicrobial resistance. S. aureus strains utilize a type VII secretion system to secrete toxins targeting competitor bacteria, likely facilitating colonization. EsaD is a nuclease toxin secreted by the type VII secretion system in many strains of S. aureus as well as other related bacterial species. Here, we identify three small proteins of previously unknown function as export factors, required for efficient secretion of EsaD. We show that these proteins bind to the transport domain of EsaD, forming a complex with a striking cane-like conformation.
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Affiliation(s)
- Yaping Yang
- Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Eleanor Boardman
- Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Justin Deme
- Center for Structural Biology, Center for Cancer Research, National Cancer Institute, NIH, Frederick, Maryland, USA
| | - Felicity Alcock
- Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Susan Lea
- Center for Structural Biology, Center for Cancer Research, National Cancer Institute, NIH, Frederick, Maryland, USA
| | - Tracy Palmer
- Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
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17
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Collars OA, Jones BS, Hu DD, Weaver SD, Sherman TA, Champion MM, Champion PA. An N-acetyltransferase required for ESAT-6 N-terminal acetylation and virulence in Mycobacterium marinum. mBio 2023; 14:e0098723. [PMID: 37772840 PMCID: PMC10653941 DOI: 10.1128/mbio.00987-23] [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: 04/25/2023] [Accepted: 08/09/2023] [Indexed: 09/30/2023] Open
Abstract
IMPORTANCE N-terminal acetylation is a protein modification that broadly impacts basic cellular function and disease in higher organisms. Although bacterial proteins are N-terminally acetylated, little is understood how N-terminal acetylation impacts bacterial physiology and pathogenesis. Mycobacterial pathogens cause acute and chronic disease in humans and in animals. Approximately 15% of mycobacterial proteins are N-terminally acetylated, but the responsible enzymes are largely unknown. We identified a conserved mycobacterial protein required for the N-terminal acetylation of 23 mycobacterial proteins including the EsxA virulence factor. Loss of this enzyme from M. marinum reduced macrophage killing and spread of M. marinum to new host cells. Defining the acetyltransferases responsible for the N-terminal protein acetylation of essential virulence factors could lead to new targets for therapeutics against mycobacteria.
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Affiliation(s)
- Owen A. Collars
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
- Eck Institute for Global Health, University of Note Dame, Notre Dame, Indiana, USA
| | - Bradley S. Jones
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
- Eck Institute for Global Health, University of Note Dame, Notre Dame, Indiana, USA
| | - Daniel D. Hu
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Simon D. Weaver
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Taylor A. Sherman
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Matthew M. Champion
- Eck Institute for Global Health, University of Note Dame, Notre Dame, Indiana, USA
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA
| | - Patricia A. Champion
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
- Eck Institute for Global Health, University of Note Dame, Notre Dame, Indiana, USA
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18
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Malakar B, Chauhan K, Sanyal P, Naz S, Kalam H, Vivek-Ananth RP, Singh LV, Samal A, Kumar D, Nandicoori VK. Phosphorylation of CFP10 modulates Mycobacterium tuberculosis virulence. mBio 2023; 14:e0123223. [PMID: 37791794 PMCID: PMC10653824 DOI: 10.1128/mbio.01232-23] [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: 05/18/2023] [Accepted: 07/25/2023] [Indexed: 10/05/2023] Open
Abstract
IMPORTANCE Secreted virulence factors play a critical role in bacterial pathogenesis. Virulence effectors not only help bacteria to overcome the host immune system but also aid in establishing infection. Mtb, which causes tuberculosis in humans, encodes various virulence effectors. Triggers that modulate the secretion of virulence effectors in Mtb are yet to be fully understood. To gain mechanistic insight into the secretion of virulence effectors, we performed high-throughput proteomic studies. With the help of system-level protein-protein interaction network analysis and empirical validations, we unravelled a link between phosphorylation and secretion. Taking the example of the well-known virulence factor of CFP10, we show that the dynamics of CFP10 phosphorylation strongly influenced bacterial virulence and survival ex vivo and in vivo. This study presents the role of phosphorylation in modulating the secretion of virulence factors.
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Affiliation(s)
- Basanti Malakar
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, India
| | - Komal Chauhan
- International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, India
| | - Priyadarshini Sanyal
- Academy of Scientific and Innovative Research (AcSIR), CSIR-Centre for Cellular and Molecular Biology Campus, Hyderabad, India
| | - Saba Naz
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, India
| | - Haroon Kalam
- International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, India
| | - R. P. Vivek-Ananth
- The Institute of Mathematical Sciences (IMSc), Homi Bhabha National Institute (HBNI), Chennai, India
| | - Lakshya Veer Singh
- International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, India
| | - Areejit Samal
- The Institute of Mathematical Sciences (IMSc), Homi Bhabha National Institute (HBNI), Chennai, India
| | - Dhiraj Kumar
- International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, India
| | - Vinay Kumar Nandicoori
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, India
- Academy of Scientific and Innovative Research (AcSIR), CSIR-Centre for Cellular and Molecular Biology Campus, Hyderabad, India
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19
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Jani C, Marsh A, Uchil P, Jain N, Baskir ZR, Glover OT, Root DE, Doench JG, Barczak AK. Vps18 contributes to phagosome membrane integrity in Mycobacterium tuberculosis-infected macrophages. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.01.560397. [PMID: 37873319 PMCID: PMC10592876 DOI: 10.1101/2023.10.01.560397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Mycobacterium tuberculosis (Mtb) has evolved to be exquisitely adapted to survive within host macrophages. The capacity to damage the phagosomal membrane has emerged as central to Mtb virulence. While Mtb factors driving membrane damage have been described, host factors that repair that damage to contain the pathogen remain largely unknown. We used a genome-wide CRISPR screen to identify novel host factors required to repair Mtb-damaged phagosomal membranes. Vacuolar protein sorting-associated protein 18 (Vps18), a member of the HOPS and CORVET trafficking complexes, was among the top hits. Vps18 colocalized with Mtb in macrophages beginning shortly after infection, and Vps18-knockout macrophages demonstrated increased damage of Mtb-containing phagosomes without impaired autophagy. Mtb grew more robustly in Vps18-knockout cells, and the first-line anti-tuberculosis antibiotic pyrazinamide was less effective. Our results identify Vps18 as required for phagosomal membrane integrity in Mtb-infected cells and suggest that modulating phagosome integrity may hold promise for improving the efficacy of antibiotic treatment for TB.
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Affiliation(s)
| | | | - Pooja Uchil
- The Ragon Institute of MGH, MIT and Harvard
- Institute of Clinical and Molecular Virology, Friedrich-Alexander Universität Erlangen-Nürnberg
| | - Neha Jain
- The Ragon Institute of MGH, MIT and Harvard
| | | | | | | | | | - Amy K Barczak
- The Ragon Institute of MGH, MIT and Harvard
- The Broad Institute
- Division of Infectious Diseases, Massachusetts General Hospital
- Department of Medicine, Harvard Medical School
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20
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Shahi I, Dongas SA, Ilmain JK, Torres VJ, Ratner AJ. Characterization of tigurilysin, a novel human CD59-specific cholesterol-dependent cytolysin, reveals a role for host specificity in augmenting toxin activity. MICROBIOLOGY (READING, ENGLAND) 2023; 169:001393. [PMID: 37702594 PMCID: PMC10569062 DOI: 10.1099/mic.0.001393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 09/05/2023] [Indexed: 09/14/2023]
Abstract
Cholesterol-dependent cytolysins (CDCs) are a large family of pore-forming toxins, produced by numerous Gram-positive pathogens. CDCs depend on host membrane cholesterol for pore formation; some CDCs also require surface-associated human CD59 (hCD59) for binding, conferring specificity for human cells. We purified a recombinant version of a putative CDC encoded in the genome of Streptococcus oralis subsp. tigurinus, tigurilysin (TGY), and used CRISPR/Cas9 to construct hCD59 knockout (KO) HeLa and JEG-3 cell lines. Cell viability assays with TGY on wild-type and hCD59 KO cells showed that TGY is a hCD59-dependent CDC. Two variants of TGY exist among S. oralis subsp. tigurinus genomes, only one of which is functional. We discovered that a single amino acid change between these two TGY variants determines its activity. Flow cytometry and oligomerization Western blots revealed that the single amino acid difference between the two TGY isoforms disrupts host cell binding and oligomerization. Furthermore, experiments with hCD59 KO cells and cholesterol-depleted cells demonstrated that TGY is fully dependent on both hCD59 and cholesterol for activity, unlike other known hCD59-dependent CDCs. Using full-length CDCs and toxin constructs differing only in the binding domain, we determined that having hCD59 dependence leads to increased lysis efficiency, conferring a potential advantage to organisms producing hCD59-dependent CDCs.
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Affiliation(s)
- Ifrah Shahi
- Department of Pediatrics, New York University Grossman School of Medicine, New York, NY, USA
| | - Sophia A. Dongas
- Department of Pediatrics, New York University Grossman School of Medicine, New York, NY, USA
| | - Juliana K. Ilmain
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, USA
| | - Victor J. Torres
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, USA
| | - Adam J. Ratner
- Department of Pediatrics, New York University Grossman School of Medicine, New York, NY, USA
- Department of Microbiology, New York University Grossman School of Medicine, New York, NY, USA
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21
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Fines DM, Schichnes D, Knight M, Anaya-Sanchez A, Thuong N, Cox J, Stanley SA. Mycobacterial formation of intracellular lipid inclusions is a dynamic process associated with rapid replication. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.10.552809. [PMID: 37609245 PMCID: PMC10441389 DOI: 10.1101/2023.08.10.552809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
Intracellular lipid inclusions (ILI) are triacylglyceride rich organelles produced by mycobacteria thought to serve as energy reservoirs. It is believed that ILI are formed as a result of a dosR mediated transition from replicative growth to non-replicating persistence (NRP). ILI rich Mycobacterium tuberculosis (Mtb) bacilli have been reported during infection and in sputum, establishing their importance in Mtb pathogenesis. Studies conducted in mycobacteria such as Mycobacterium smegmatis, Mycobacterium abscessus, or lab Mtb strains have demonstrated ILI formation in the presence of hypoxic, nitric oxide, nutrient limitation, or low nitrogen stress, conditions believed to emulate the host environment within which Mtb resides. Here, we show that M. marinum and clinical Mtb isolates make ILI during active replication in axenic culture independent of environmental stressors. By tracking ILI formation dynamics we demonstrate that ILI are quickly formed in the presence of fresh media or exogenous fatty acids but are rapidly depleted while bacteria are still actively replicating. We also show that the cell envelope is an alternate site for neutral lipid accumulation observed during stationary phase. In addition, we screen a panel of 60 clinical isolates and observe variation in ILI production during early log phase growth between and among Mtb lineages. Finally, we show that dosR expression level does not strictly correlate with ILI accumulation in fresh clinical isolates. Taken together, our data provide evidence of an active ILI formation pathway in replicating mycobacteria cultured in the absence of stressors, suggesting a decoupling of ILI formation from NRP.
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22
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Shahi I, Dongas SA, Ilmain JK, Torres VJ, Ratner AJ. Characterization of Tigurilysin, a Novel Human CD59-Specific Cholesterol-Dependent Cytolysin, Reveals a Role for Host Specificity in Augmenting Toxin Activity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.21.545930. [PMID: 37546867 PMCID: PMC10401958 DOI: 10.1101/2023.06.21.545930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Cholesterol dependent cytolysins (CDCs) are a large family of pore forming toxins, produced by numerous gram-positive pathogens. CDCs depend on host membrane cholesterol for pore formation; some CDCs also require surface associated human CD59 (hCD59) for binding, conferring specificity for human cells. We purified a recombinant version of a putative CDC encoded in the genome of Streptococcus oralis subsp. tigurinus , tigurilysin (TGY), and used CRISPR/Cas9 to construct hCD59 knockout (KO) HeLa and JEG-3 cell lines. Cell viability assays with TGY on WT and hCD59 KO cells showed that TGY is a hCD59-dependent CDC. Two variants of TGY exist among S. oralis subsp. tigurinus genomes, only one of which is functional. We discovered that a single amino acid change between these two TGY variants determines its activity. Flow cytometry and oligomerization western blots revealed that the single amino acid difference between the two TGY isoforms disrupts host cell binding and oligomerization. Furthermore, experiments with hCD59 KO cells and cholesterol depleted cells demonstrated that TGY is fully dependent on both hCD59 and cholesterol for activity, unlike other known hCD59-dependent CDCs. Using full-length CDCs and toxin constructs differing only in the binding domain, we determined that having hCD59-dependence leads to increased lysis efficiency, conferring a potential advantage to organisms producing hCD59-dependent CDCs. IMPORTANCE Cholesterol dependent cytolysins (CDCs) are produced by a variety of disease-causing bacteria, and may play a significant role in pathogenesis. Understanding CDC mechanisms of action provides useful information for developing anti-virulence strategies against bacteria that utilize CDCs and other pore-forming toxins in pathogenesis. This study describes for the first time a novel human-specific CDC with an atypical pore forming mechanism compared to known CDCs. In addition, this study demonstrates that human-specificity potentially confers increased lytic efficiency to CDCs. These data provide a possible explanation for the selective advantage of developing hCD59-dependency in CDCs and the consequent host restriction.
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Affiliation(s)
- Ifrah Shahi
- New York University Grossman School of Medicine, Department of Pediatrics, New York, NY
| | - Sophia A. Dongas
- New York University Grossman School of Medicine, Department of Pediatrics, New York, NY
| | - Juliana K. Ilmain
- New York University Grossman School of Medicine, Department of Microbiology, New York, NY
| | - Victor J. Torres
- New York University Grossman School of Medicine, Department of Microbiology, New York, NY
| | - Adam J. Ratner
- New York University Grossman School of Medicine, Department of Pediatrics, New York, NY
- New York University Grossman School of Medicine, Department of Microbiology, New York, NY
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23
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Vargas R, Luna MJ, Freschi L, Marin M, Froom R, Murphy KC, Campbell EA, Ioerger TR, Sassetti CM, Farhat MR. Phase variation as a major mechanism of adaptation in Mycobacterium tuberculosis complex. Proc Natl Acad Sci U S A 2023; 120:e2301394120. [PMID: 37399390 PMCID: PMC10334774 DOI: 10.1073/pnas.2301394120] [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: 02/05/2023] [Accepted: 05/03/2023] [Indexed: 07/05/2023] Open
Abstract
Phase variation induced by insertions and deletions (INDELs) in genomic homopolymeric tracts (HT) can silence and regulate genes in pathogenic bacteria, but this process is not characterized in MTBC (Mycobacterium tuberculosis complex) adaptation. We leverage 31,428 diverse clinical isolates to identify genomic regions including phase-variants under positive selection. Of 87,651 INDEL events that emerge repeatedly across the phylogeny, 12.4% are phase-variants within HTs (0.02% of the genome by length). We estimated the in-vitro frameshift rate in a neutral HT at 100× the neutral substitution rate at [Formula: see text] frameshifts/HT/year. Using neutral evolution simulations, we identified 4,098 substitutions and 45 phase-variants to be putatively adaptive to MTBC (P < 0.002). We experimentally confirm that a putatively adaptive phase-variant alters the expression of espA, a critical mediator of ESX-1-dependent virulence. Our evidence supports the hypothesis that phase variation in the ESX-1 system of MTBC can act as a toggle between antigenicity and survival in the host.
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Affiliation(s)
- Roger Vargas
- Center for Computational Biomedicine, Harvard Medical School, Boston, MA02115
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA02115
| | - Michael J. Luna
- Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, MA01655
| | - Luca Freschi
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA02115
| | - Maximillian Marin
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA02115
| | - Ruby Froom
- Laboratory of Molecular Biophysics, The Rockefeller University, New York, NY10065
- Laboratory of Host-Pathogen Biology, The Rockefeller University, New York, NY10065
| | - Kenan C. Murphy
- Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, MA01655
| | | | - Thomas R. Ioerger
- Department of Computer Science and Engineering, Texas A&M University, College Station, TX77843
| | - Christopher M. Sassetti
- Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, MA01655
| | - Maha Reda Farhat
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA02115
- Pulmonary and Critical Care Medicine, Massachusetts General Hospital, Boston, MA02114
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24
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Anes E, Pires D, Mandal M, Azevedo-Pereira JM. ESAT-6 a Major Virulence Factor of Mycobacterium tuberculosis. Biomolecules 2023; 13:968. [PMID: 37371548 DOI: 10.3390/biom13060968] [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: 04/28/2023] [Revised: 05/31/2023] [Accepted: 06/07/2023] [Indexed: 06/29/2023] Open
Abstract
Mycobacterium tuberculosis (Mtb), the causative agent of human tuberculosis (TB), is one of the most successfully adapted human pathogens. Human-to-human transmission occurs at high rates through aerosols containing bacteria, but the pathogen evolved prior to the establishment of crowded populations. Mtb has developed a particular strategy to ensure persistence in the host until an opportunity for transmission arises. It has refined its lifestyle to obviate the need for virulence factors such as capsules, flagella, pili, or toxins to circumvent mucosal barriers. Instead, the pathogen uses host macrophages, where it establishes intracellular niches for its migration into the lung parenchyma and other tissues and for the induction of long-lived latency in granulomas. Finally, at the end of the infection cycle, Mtb induces necrotic cell death in macrophages to escape to the extracellular milieu and instructs a strong inflammatory response that is required for the progression from latency to disease and transmission. Common to all these events is ESAT-6, one of the major virulence factors secreted by the pathogen. This narrative review highlights the recent advances in understanding the role of ESAT-6 in hijacking macrophage function to establish successful infection and transmission and its use as a target for the development of diagnostic tools and vaccines.
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Affiliation(s)
- Elsa Anes
- Host-Pathogen Interactions Unit, Research Institute for Medicines, iMed.ULisboa, Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - David Pires
- Host-Pathogen Interactions Unit, Research Institute for Medicines, iMed.ULisboa, Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
- Center for Interdisciplinary Research in Health, Católica Medical School, Universidade Católica Portuguesa, Estrada Octávio Pato, 2635-631 Rio de Mouro, Portugal
| | - Manoj Mandal
- Host-Pathogen Interactions Unit, Research Institute for Medicines, iMed.ULisboa, Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - José Miguel Azevedo-Pereira
- Host-Pathogen Interactions Unit, Research Institute for Medicines, iMed.ULisboa, Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
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25
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Yang Y, Boardman E, Deme J, Alcock F, Lea S, Palmer T. Three small partner proteins facilitate the type VII-dependent secretion export of an antibacterial nuclease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.01.535202. [PMID: 37461441 PMCID: PMC10350083 DOI: 10.1101/2023.04.01.535202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 07/24/2023]
Abstract
The type VIIb protein secretion system (T7SSb) plays a role in interbacterial competition in Gram-positive Firmicute bacteria and secretes various toxic effector proteins. The mechanism of secretion and the roles of numerous conserved genes within T7SSb gene clusters remain unknown. EsaD is a nuclease toxin secreted by the Staphylococcus aureus T7SSb, which forms a complex with its cognate immunity protein, EsaG, and chaperone EsaE. Encoded upstream of EsaD are three small secreted proteins, EsxB, EsxC and EsxD. Here we show that EsxBCD bind to the transport domain of EsaD and function as EsaD export factors. We report the first structural information for a complete T7SSb substrate pre-secretion complex. Cryo-EM of the EsaDEG trimer and the EsaDEG-EsxBCD hexamer shows that incorporation of EsxBCD confers a conformation comprising a flexible globular cargo domain attached to a long narrow shaft that is likely to be crucial for efficient toxin export.
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Affiliation(s)
- Yaping Yang
- Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Eleanor Boardman
- Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Justin Deme
- Center for Structural Biology, Center for Cancer Research, National Cancer Institute, NIH, Frederick, MD 21702
| | - Felicity Alcock
- Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Susan Lea
- Center for Structural Biology, Center for Cancer Research, National Cancer Institute, NIH, Frederick, MD 21702
| | - Tracy Palmer
- Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
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26
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Leddy O, White FM, Bryson BD. Immunopeptidomics reveals determinants of Mycobacterium tuberculosis antigen presentation on MHC class I. eLife 2023; 12:e84070. [PMID: 37073954 PMCID: PMC10159623 DOI: 10.7554/elife.84070] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 04/17/2023] [Indexed: 04/20/2023] Open
Abstract
CD8+ T cell recognition of Mycobacterium tuberculosis (Mtb)-specific peptides presented on major histocompatibility complex class I (MHC-I) contributes to immunity to tuberculosis (TB), but the principles that govern presentation of Mtb antigens on MHC-I are incompletely understood. In this study, mass spectrometry (MS) analysis of the MHC-I repertoire of Mtb-infected primary human macrophages reveals that substrates of Mtb's type VII secretion systems (T7SS) are overrepresented among Mtb-derived peptides presented on MHC-I. Quantitative, targeted MS shows that ESX-1 activity is required for presentation of Mtb peptides derived from both ESX-1 substrates and ESX-5 substrates on MHC-I, consistent with a model in which proteins secreted by multiple T7SSs access a cytosolic antigen processing pathway via ESX-1-mediated phagosome permeabilization. Chemical inhibition of proteasome activity, lysosomal acidification, or cysteine cathepsin activity did not block presentation of Mtb antigens on MHC-I, suggesting involvement of other proteolytic pathways or redundancy among multiple pathways. Our study identifies Mtb antigens presented on MHC-I that could serve as targets for TB vaccines, and reveals how the activity of multiple T7SSs interacts to contribute to presentation of Mtb antigens on MHC-I.
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Affiliation(s)
- Owen Leddy
- Department of Biological Engineering, Massachusetts Institute of TechnologyCambridgeUnited States
- Ragon Institute of Massachusetts General Hospital, Harvard, and MITCambridgeUnited States
- Koch Institute for Integrative Cancer ResearchCambridgeUnited States
| | - Forest M White
- Department of Biological Engineering, Massachusetts Institute of TechnologyCambridgeUnited States
- Koch Institute for Integrative Cancer ResearchCambridgeUnited States
- Center for Precision Cancer MedicineCambridgeUnited States
| | - Bryan D Bryson
- Department of Biological Engineering, Massachusetts Institute of TechnologyCambridgeUnited States
- Ragon Institute of Massachusetts General Hospital, Harvard, and MITCambridgeUnited States
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27
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Toniolo C, Dhar N, McKinney JD. Uptake-independent killing of macrophages by extracellular Mycobacterium tuberculosis aggregates. EMBO J 2023; 42:e113490. [PMID: 36920246 PMCID: PMC10152147 DOI: 10.15252/embj.2023113490] [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: 01/11/2023] [Revised: 01/30/2023] [Accepted: 02/23/2023] [Indexed: 03/16/2023] Open
Abstract
Mycobacterium tuberculosis (Mtb) infection is initiated by inhalation of bacteria into lung alveoli, where they are phagocytosed by resident macrophages. Intracellular Mtb replication induces the death of the infected macrophages and the release of bacterial aggregates. Here, we show that these aggregates can evade phagocytosis by killing macrophages in a contact-dependent but uptake-independent manner. We use time-lapse fluorescence microscopy to show that contact with extracellular Mtb aggregates triggers macrophage plasma membrane perturbation, cytosolic calcium accumulation, and pyroptotic cell death. These effects depend on the Mtb ESX-1 secretion system, however, this system alone cannot induce calcium accumulation and macrophage death in the absence of the Mtb surface-exposed lipid phthiocerol dimycocerosate. Unexpectedly, we found that blocking ESX-1-mediated secretion of the EsxA/EsxB virulence factors does not eliminate the uptake-independent killing of macrophages and that the 50-kDa isoform of the ESX-1-secreted protein EspB can mediate killing in the absence of EsxA/EsxB secretion. Treatment with an ESX-1 inhibitor reduces uptake-independent killing of macrophages by Mtb aggregates, suggesting that novel therapies targeting this anti-phagocytic mechanism could prevent the propagation of extracellular bacteria within the lung.
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Affiliation(s)
- Chiara Toniolo
- School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), Lausanne, Switzerland
| | - Neeraj Dhar
- School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), Lausanne, Switzerland.,Vaccine and Infectious Disease Organization, University of Saskatchewan, Saskatoon, SK, Canada.,Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, SK, Canada
| | - John D McKinney
- School of Life Sciences, Swiss Federal Institute of Technology in Lausanne (EPFL), Lausanne, Switzerland
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28
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Collars OA, Jones BS, Hu DD, Weaver SD, Champion MM, Champion PA. An N-acetyltransferase required for EsxA N-terminal protein acetylation and virulence in Mycobacterium marinum. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.14.532585. [PMID: 36993388 PMCID: PMC10055061 DOI: 10.1101/2023.03.14.532585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
N-terminal protein acetylation is a ubiquitous post-translational modification that broadly impacts diverse cellular processes in higher organisms. Bacterial proteins are also N-terminally acetylated, but the mechanisms and consequences of this modification in bacteria are poorly understood. We previously quantified widespread N-terminal protein acetylation in pathogenic mycobacteria (C. R. Thompson, M. M. Champion, and P.A. Champion, J Proteome Res 17(9): 3246-3258, 2018, https:// doi: 10.1021/acs.jproteome.8b00373). The major virulence factor EsxA (ESAT-6, Early secreted antigen, 6kDa) was one of the first N-terminally acetylated proteins identified in bacteria. EsxA is conserved in mycobacterial pathogens, including Mycobacterium tuberculosis and Mycobacterium marinum, a non-tubercular mycobacterial species that causes tuberculosis-like disease in ectotherms. However, enzyme responsible for EsxA N-terminal acetylation has been elusive. Here, we used genetics, molecular biology, and mass-spectroscopy based proteomics to demonstrate that MMAR_1839 (renamed Emp1, ESX-1 modifying protein, 1) is the putative N-acetyl transferase (NAT) solely responsible for EsxA acetylation in Mycobacterium marinum. We demonstrated that ERD_3144, the orthologous gene in M. tuberculosis Erdman, is functionally equivalent to Emp1. We identified at least 22 additional proteins that require Emp1 for acetylation, demonstrating that this putative NAT is not dedicated to EsxA. Finally, we showed that loss of emp1 resulted in a significant reduction in the ability of M. marinum to cause macrophage cytolysis. Collectively, this study identified a NAT required for N-terminal acetylation in Mycobacterium and provided insight into the requirement of N-terminal acetylation of EsxA and other proteins in mycobacterial virulence in the macrophage.
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Affiliation(s)
- Owen A. Collars
- Department of Biological Sciences, University of Notre Dame, Notre Dame, USA
- Eck Institute for Global Health, University of Note Dame, Notre Dame, USA
| | - Bradley S. Jones
- Department of Biological Sciences, University of Notre Dame, Notre Dame, USA
- Eck Institute for Global Health, University of Note Dame, Notre Dame, USA
| | - Daniel D. Hu
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, USA
| | - Simon D. Weaver
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, USA
| | - Matthew M. Champion
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, USA
- Eck Institute for Global Health, University of Note Dame, Notre Dame, USA
| | - Patricia A. Champion
- Department of Biological Sciences, University of Notre Dame, Notre Dame, USA
- Eck Institute for Global Health, University of Note Dame, Notre Dame, USA
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29
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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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30
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Olive AJ, Smith CM, Baer CE, Coers J, Sassetti CM. Mycobacterium tuberculosis Evasion of Guanylate Binding Protein-Mediated Host Defense in Mice Requires the ESX1 Secretion System. Int J Mol Sci 2023; 24:2861. [PMID: 36769182 PMCID: PMC9917499 DOI: 10.3390/ijms24032861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/24/2023] [Accepted: 01/30/2023] [Indexed: 02/05/2023] Open
Abstract
Cell-intrinsic immune mechanisms control intracellular pathogens that infect eukaryotes. The intracellular pathogen Mycobacterium tuberculosis (Mtb) evolved to withstand cell-autonomous immunity to cause persistent infections and disease. A potent inducer of cell-autonomous immunity is the lymphocyte-derived cytokine IFNγ. While the production of IFNγ by T cells is essential to protect against Mtb, it is not capable of fully eradicating Mtb infection. This suggests that Mtb evades a subset of IFNγ-mediated antimicrobial responses, yet what mechanisms Mtb resists remains unclear. The IFNγ-inducible Guanylate binding proteins (GBPs) are key host defense proteins able to control infections with intracellular pathogens. GBPs were previously shown to directly restrict Mycobacterium bovis BCG yet their role during Mtb infection has remained unknown. Here, we examine the importance of a cluster of five GBPs on mouse chromosome 3 in controlling Mycobacterial infection. While M. bovis BCG is directly restricted by GBPs, we find that the GBPs on chromosome 3 do not contribute to the control of Mtb replication or the associated host response to infection. The differential effects of GBPs during Mtb versus M. bovis BCG infection is at least partially explained by the absence of the ESX1 secretion system from M. bovis BCG, since Mtb mutants lacking the ESX1 secretion system become similarly susceptible to GBP-mediated immune defense. Therefore, this specific genetic interaction between the murine host and Mycobacteria reveals a novel function for the ESX1 virulence system in the evasion of GBP-mediated immunity.
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Affiliation(s)
- Andrew J. Olive
- Department of Microbiology & Molecular Genetics, College of Osteopathic Medicine, Michigan State University, East Lansing, MI 48824, USA
| | - Clare M. Smith
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 22710, USA
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
| | - Christina E. Baer
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA 01650, USA
| | - Jörn Coers
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 22710, USA
- Department of Immunology, Duke University Medical Center, Durham, NC 22710, USA
| | - Christopher M. Sassetti
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA 01650, USA
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31
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The ESX-1 Substrate PPE68 Has a Key Function in ESX-1-Mediated Secretion in Mycobacterium marinum. mBio 2022; 13:e0281922. [PMID: 36409073 PMCID: PMC9765416 DOI: 10.1128/mbio.02819-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Mycobacteria use specialized type VII secretion systems (T7SSs) to secrete proteins across their diderm cell envelope. One of the T7SS subtypes, named ESX-1, is a major virulence determinant in pathogenic species such as Mycobacterium tuberculosis and the fish pathogen Mycobacterium marinum. ESX-1 secretes a variety of substrates, called Esx, PE, PPE, and Esp proteins, at least some of which are folded heterodimers. Investigation into the functions of these substrates is problematic, because of the intricate network of codependent secretion between several ESX-1 substrates. Here, we describe the ESX-1 substrate PPE68 as essential for secretion of the highly immunogenic substrates EsxA and EspE via the ESX-1 system in M. marinum. While secreted PPE68 is processed on the cell surface, the majority of cell-associated PPE68 of M. marinum and M. tuberculosis is present in a cytosolic complex with its PE partner and the EspG1 chaperone. Interfering with the binding of EspG1 to PPE68 blocked its export and the secretion of EsxA and EspE. In contrast, esxA was not required for the secretion of PPE68, revealing a hierarchy in codependent secretion. Remarkably, the final 10 residues of PPE68, a negatively charged domain, seem essential for EspE secretion, but not for the secretion of EsxA and of PPE68 itself. This indicates that distinctive domains of PPE68 are involved in secretion of the different ESX-1 substrates. Based on these findings, we propose a mechanistic model for the central role of PPE68 in ESX-1-mediated secretion and substrate codependence. IMPORTANCE Pathogenic mycobacteria, such Mycobacterium tuberculosis and Mycobacterium marinum, use a type VII secretion system (T7SS) subtype, called ESX-1, to mediate intracellular survival via phagosomal rupture and subsequent translocation of the mycobacterium to the host cytosol. Identifying the ESX-1 substrate that is responsible for this process is problematic because of the intricate network of codependent secretion between ESX-1 substrates. Here, we show the central role of the ESX-1 substrate PPE68 for the secretion of ESX-1 substrates in Mycobacterium marinum. Unravelling the mechanism of codependent secretion will aid the functional understanding of T7SSs and will allow the analysis of the individual roles of ESX-1 substrates in the virulence caused by the significant human pathogen Mycobacterium tuberculosis.
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Functional Analysis of EspM, an ESX-1-Associated Transcription Factor in Mycobacterium marinum. J Bacteriol 2022; 204:e0023322. [PMID: 36448785 PMCID: PMC9765225 DOI: 10.1128/jb.00233-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Pathogenic mycobacteria use the ESX-1 secretion system to escape the macrophage phagosome and survive infection. We demonstrated that the ESX-1 system is regulated by feedback control in Mycobacterium marinum, a nontuberculous pathogen and model for the human pathogen Mycobacterium tuberculosis. In the presence of a functional ESX-1 system, the WhiB6 transcription factor upregulates expression of ESX-1 substrate genes. In the absence of an assembled ESX-1 system, the conserved transcription factor, EspM, represses whiB6 expression by specifically binding the whiB6 promoter. Together, WhiB6 and EspM fine-tune the levels of ESX-1 substrates in response to the secretion system. The mechanisms underlying control of the ESX-1 system by EspM are unknown. Here, we conduct a structure and function analysis to investigate how EspM is regulated. Using biochemical approaches, we measured the formation of higher-order oligomers of EspM in vitro. We demonstrate that multimerization in vitro can be mediated through multiple domains of the EspM protein. Using a bacterial monohybrid system, we showed that EspM self-associates through multiple domains in Escherichia coli. Using this system, we performed a genetic screen to identify EspM variants that failed to self-associate. The screen yielded four EspM variants of interest, which we tested for activity in M. marinum. Our study revealed that the two helix-turn-helix domains are functionally distinct. Moreover, the helix bundle domain is required for wild-type multimerization in vitro. Our data support models where EspM monomers or hexamers contribute to the regulation of whiB6 expression. IMPORTANCE Pathogenic mycobacteria are bacteria that pose a large burden to human health globally. The ESX-1 secretion system is required for pathogenic mycobacteria to survive within and interact with the host. Proper function of the ESX-1 secretion system is achieved by tightly controlling the expression of secreted virulence factors, in part through transcriptional regulation. Here, we characterize the conserved transcription factor EspM, which regulates the expression of ESX-1 virulence factors. We define domains required for EspM to form multimers and bind DNA. These findings provide an initial characterization an ESX-1 transcription factor and provide insights into its mechanism of action.
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33
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Saelens JW, Sweeney MI, Viswanathan G, Xet-Mull AM, Jurcic Smith KL, Sisk DM, Hu DD, Cronin RM, Hughes EJ, Brewer WJ, Coers J, Champion MM, Champion PA, Lowe CB, Smith CM, Lee S, Stout JE, Tobin DM. An ancestral mycobacterial effector promotes dissemination of infection. Cell 2022; 185:4507-4525.e18. [PMID: 36356582 PMCID: PMC9691622 DOI: 10.1016/j.cell.2022.10.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 08/27/2022] [Accepted: 10/16/2022] [Indexed: 11/11/2022]
Abstract
The human pathogen Mycobacterium tuberculosis typically causes lung disease but can also disseminate to other tissues. We identified a M. tuberculosis (Mtb) outbreak presenting with unusually high rates of extrapulmonary dissemination and bone disease. We found that the causal strain carried an ancestral full-length version of the type VII-secreted effector EsxM rather than the truncated version present in other modern Mtb lineages. The ancestral EsxM variant exacerbated dissemination through enhancement of macrophage motility, increased egress of macrophages from established granulomas, and alterations in macrophage actin dynamics. Reconstitution of the ancestral version of EsxM in an attenuated modern strain of Mtb altered the migratory mode of infected macrophages, enhancing their motility. In a zebrafish model, full-length EsxM promoted bone disease. The presence of a derived nonsense variant in EsxM throughout the major Mtb lineages 2, 3, and 4 is consistent with a role for EsxM in regulating the extent of dissemination.
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Affiliation(s)
- Joseph W Saelens
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Mollie I Sweeney
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Gopinath Viswanathan
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Ana María Xet-Mull
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Kristen L Jurcic Smith
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Dana M Sisk
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Daniel D Hu
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Rachel M Cronin
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Erika J Hughes
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA
| | - W Jared Brewer
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Jörn Coers
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA; Department of Immunology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Matthew M Champion
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, USA; Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Patricia A Champion
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA; Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Craig B Lowe
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Clare M Smith
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Sunhee Lee
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA; Department of Medicine, Duke University School of Medicine, Durham, NC 27710, USA; Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Jason E Stout
- Department of Medicine, Duke University School of Medicine, Durham, NC 27710, USA; Division of Infectious Diseases and International Health, Duke University School of Medicine, Durham, NC 27710, USA.
| | - David M Tobin
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA; Department of Immunology, Duke University School of Medicine, Durham, NC 27710, USA.
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Korotetskaya MV, Rubakova EI. Metabolic biological markers for diagnosing and monitoring the course of tuberculosis. RUSSIAN JOURNAL OF INFECTION AND IMMUNITY 2022. [DOI: 10.15789/2220-7619-mbm-1947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The international biomedical community has been currently facing a need to find a simple and most accessible type of analysis that helps to diagnose tuberculosis (TB) with the maximum reliability even before the onset of clinical manifestations. Tuberculosis results in more deaths than any other pathogen, second only to pneumonia caused by the SARS-CoV-2 virus, but the majority of infected people remain asymptomatic. In addition, it is important to develop methods to distinguish various forms of tuberculosis infection course at early stages and to reliably stratify patients into appropriate groups (persons with a rapidly progressing infection, chronic course, latent infection carriers). Immunometabolism investigates a relationship between bioenergetic pathways and specific functions of immune cells that has recently become increasingly important in scientific research. The host anti-mycobacteria immune response in tuberculosis is regulated by a number of metabolic networks that can interact both cooperatively and antagonistically, influencing an outcome of the disease. The balance between inflammatory and immune reactions limits the spread of mycobacteria in vivo and protects from developing tuberculosis. Cytokines are essential for host defense, but if uncontrolled, some mediators may contribute to developing disease and pathology. Differences in plasma levels of metabolites between individuals with advanced infection, LTBI and healthy individuals can be detected long before the onset of the major related clinical signs. Changes in amino acid and cortisol level may be detected as early as 12 months before the onset of the disease and become more prominent at verifying clinical diagnosis. Assessing serum level of certain amino acids and their ratios may be used as additional diagnostic markers of active pulmonary TB. Metabolites, including serum fatty acids, amino acids and lipids may contribute to detecting active TB. Metabolic profiles indicate about increased indolamine 2.3-dioxygenase 1 (IDO1) activity, decreased phospholipase activity, increased adenosine metabolite level, and fibrous lesions in active vs. latent infection. TB treatment can be adjusted based on individual patient metabolism and biomarker profiles. Thus, exploring immunometabolism in tuberculosis is necessary for development of new therapeutic strategies.
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Amaral EP, Foreman TW, Namasivayam S, Hilligan KL, Kauffman KD, Barbosa Bomfim CC, Costa DL, Barreto-Duarte B, Gurgel-Rocha C, Santana MF, Cordeiro-Santos M, Du Bruyn E, Riou C, Aberman K, Wilkinson RJ, Barber DL, Mayer-Barber KD, Andrade BB, Sher A. GPX4 regulates cellular necrosis and host resistance in Mycobacterium tuberculosis infection. J Exp Med 2022; 219:e20220504. [PMID: 36069923 PMCID: PMC9458471 DOI: 10.1084/jem.20220504] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 06/23/2022] [Accepted: 08/11/2022] [Indexed: 01/15/2023] Open
Abstract
Cellular necrosis during Mycobacterium tuberculosis (Mtb) infection promotes both immunopathology and bacterial dissemination. Glutathione peroxidase-4 (Gpx4) is an enzyme that plays a critical role in preventing iron-dependent lipid peroxidation-mediated cell death (ferroptosis), a process previously implicated in the necrotic pathology seen in Mtb-infected mice. Here, we document altered GPX4 expression, glutathione levels, and lipid peroxidation in patients with active tuberculosis and assess the role of this pathway in mice genetically deficient in or overexpressing Gpx4. We found that Gpx4-deficient mice infected with Mtb display substantially increased lung necrosis and bacterial burdens, while transgenic mice overexpressing the enzyme show decreased bacterial loads and necrosis. Moreover, Gpx4-deficient macrophages exhibited enhanced necrosis upon Mtb infection in vitro, an outcome suppressed by the lipid peroxidation inhibitor, ferrostatin-1. These findings provide support for the role of ferroptosis in Mtb-induced necrosis and implicate the Gpx4/GSH axis as a target for host-directed therapy of tuberculosis.
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Affiliation(s)
- Eduardo P. Amaral
- Immunobiology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, MD
| | - Taylor W. Foreman
- T Lymphocyte Biology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, MD
| | - Sivaranjani Namasivayam
- Immunobiology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, MD
| | - Kerry L. Hilligan
- Immunobiology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, MD
| | - Keith D. Kauffman
- T Lymphocyte Biology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, MD
| | - Caio Cesar Barbosa Bomfim
- Immunobiology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, MD
| | - Diego L. Costa
- Departmento de Bioquímica e Imunologia, Programa de Pós-Graduação em Imunologia Básica e Aplicada, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Beatriz Barreto-Duarte
- Laboratório de Inflamação e Biomarcadores, Instituto Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Bahia, Brazil
- Multinational Organization Network Sponsoring Translational and Epidemiological Research Initiative, Salvador, Brazil
- Curso de Medicina, Universidade Salvador, Laureate Universities, Salvador, Brazil
| | - Clarissa Gurgel-Rocha
- Department of Pathology, School of Medicine of the Federal University of Bahia, Salvador, Bahia, Brazil
- Center for Biotechnology and Cell Therapy, D’Or Institute for Research and Education, Sao Rafael Hospital, Salvador, Bahia, Brazil
| | - Monique Freire Santana
- Departmento de Ensino e Pesquisa, Fundação Centro de Controle de Oncologia do Estado do Amazonas, Manaus, Brazil
- Fundação Medicina Tropical Doutor Heitor Vieira Dourado, Manaus, Brazil
- Programa de Pós-Graduação em Medicina Tropical, Universidade do Estado do Amazonas, Manaus, Brazil
| | - Marcelo Cordeiro-Santos
- Fundação Medicina Tropical Doutor Heitor Vieira Dourado, Manaus, Brazil
- Programa de Pós-Graduação em Medicina Tropical, Universidade do Estado do Amazonas, Manaus, Brazil
- Faculdade de Medicina, Universidade Nilton Lins, Manaus, Brazil
| | - Elsa Du Bruyn
- Wellcome Centre for Infectious Disease Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Catherine Riou
- Wellcome Centre for Infectious Disease Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Kate Aberman
- Immunobiology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, MD
| | - Robert John Wilkinson
- Wellcome Centre for Infectious Disease Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
- The Francis Crick Institute, London, Northwick Park Hospital, Harrow, UK
- Department of Infectious Disease, Imperial College London, London, UK
| | - Daniel L. Barber
- T Lymphocyte Biology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, MD
| | - Katrin D. Mayer-Barber
- Inflammation and Innate Immunity Unit, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
| | - Bruno B. Andrade
- Laboratório de Inflamação e Biomarcadores, Instituto Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Bahia, Brazil
- Multinational Organization Network Sponsoring Translational and Epidemiological Research Initiative, Salvador, Brazil
- Curso de Medicina, Universidade Salvador, Laureate Universities, Salvador, Brazil
- Curso de Medicina, Escola Bahiana de Medicina e Saúde Pública, Salvador, Bahia, Brazil
- Faculdade de Medicina, Universidade Federal da Bahia, Salvador, Brazil
- Curso de Medicina, Universidade Faculdade de Tecnologia e Ciências, Salvador, Bahia, Brazil
- Division of Infectious Diseases, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN
| | - Alan Sher
- Immunobiology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, MD
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Garrett SR, Mariano G, Dicks J, Palmer T. Homologous recombination between tandem paralogues drives evolution of a subset of type VII secretion system immunity genes in firmicute bacteria. Microb Genom 2022; 8. [PMID: 35960642 PMCID: PMC9484751 DOI: 10.1099/mgen.0.000868] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The type VII secretion system (T7SS) is found in many Gram-positive firmicutes and secretes protein toxins that mediate bacterial antagonism. Two T7SS toxins have been identified in Staphylococcus aureus, EsaD a nuclease toxin that is counteracted by the EsaG immunity protein, and TspA, which has membrane depolarising activity and is neutralised by TsaI. Both toxins are polymorphic, and strings of non-identical esaG and tsaI immunity genes are encoded in all S. aureus strains. To investigate the evolution of esaG repertoires, we analysed the sequences of the tandem esaG genes and their encoded proteins. We identified three blocks of high sequence similarity shared by all esaG genes and identified evidence of extensive recombination events between esaG paralogues facilitated through these conserved sequence blocks. Recombination between these blocks accounts for loss and expansion of esaG genes in S. aureus genomes and we identified evidence of such events during evolution of strains in clonal complex 8. TipC, an immunity protein for the TelC lipid II phosphatase toxin secreted by the streptococcal T7SS, is also encoded by multiple gene paralogues. Two blocks of high sequence similarity locate to the 5′ and 3′ end of tipC genes, and we found strong evidence for recombination between tipC paralogues encoded by Streptococcus mitis BCC08. By contrast, we found only a single homology block across tsaI genes, and little evidence for intergenic recombination within this gene family. We conclude that homologous recombination is one of the drivers for the evolution of T7SS immunity gene clusters.
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Affiliation(s)
- Stephen R Garrett
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Giuseppina Mariano
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Jo Dicks
- Culture Collections, UK Health Security Agency, 61 Colindale Ave, London, NW9 5EQ, UK
| | - Tracy Palmer
- Microbes in Health and Disease Theme, Newcastle University Biosciences Institute, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
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37
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Secretory proteins of
Mycobacterium tuberculosis
and their roles in modulation of host immune responses: focus on therapeutic targets. FEBS J 2022; 289:4146-4171. [DOI: 10.1111/febs.16369] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 01/04/2022] [Accepted: 01/21/2022] [Indexed: 12/01/2022]
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Gauthier DT, Doss JH, LaGatta M, Gupta T, Karls RK, Quinn FD. Genomic Degeneration and Reduction in the Fish Pathogen Mycobacterium shottsii. Microbiol Spectr 2022; 10:e0115821. [PMID: 35579461 PMCID: PMC9241763 DOI: 10.1128/spectrum.01158-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 04/26/2022] [Indexed: 01/17/2023] Open
Abstract
Mycobacterium shottsii is a dysgonic, nonpigmented mycobacterium originally isolated from diseased striped bass (Morone saxatilis) in the Chesapeake Bay, USA. Genomic analysis reveals that M. shottsii is a Mycobacterium ulcerans/Mycobacterium marinum clade (MuMC) member, but unlike the superficially similar M. pseudoshottsii, also isolated from striped bass, it is not an M. ulcerans ecovar, instead belonging to a transitional group of strains basal to proposed "Aronson" and "M" lineages. Although phylogenetically distinct from the human pathogen M. ulcerans, the M. shottsii genome shows parallel but nonhomologous genomic degeneration, including massive accumulation of pseudogenes accompanied by proliferation of unique insertion sequences (ISMysh01, ISMysh03), large-scale deletions, and genomic reorganization relative to typical M. marinum strains. Coupled with its observed ecological characteristics and loss of chromogenicity, the genomic structure of M. shottsii is suggestive of evolution toward a state of obligate pathogenicity, as observed for other Mycobacterium spp., including M. ulcerans, M. tuberculosis, and M. leprae. IMPORTANCE Morone saxatilis (striped bass) is an ecologically and economically important finfish species on the United States east coast. Mycobacterium shottsii and Mycobacterium pseudoshottsii were originally described in the early 2000s as novel species from outbreaks of visceral and dermal mycobacteriosis in this species. Biochemical and genetic characterization place these species within the Mycobacterium ulcerans/M. marinum clade (MuMC), and M. pseudoshottsii has been proposed as an ecovar of M. ulcerans. Here, we describe the complete genome of M. shottsii, demonstrating that it is clearly not an M. ulcerans ecovar; however, it has undergone parallel genomic modification suggestive of a transition to obligate pathogenicity. As in M. ulcerans, the M. shottsii genome demonstrates widespread pseudogene formation driven by proliferation of insertion sequences, as well as genomic reorganization. This work clarifies the phylogenetic position of M. shottsii relative to other MuMC members and provides insight into processes shaping its genomic structure.
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Affiliation(s)
- D. T. Gauthier
- Department of Biological Sciences, Old Dominion University, Norfolk, Virginia, USA
| | - J. H. Doss
- Department of Biological Sciences, Old Dominion University, Norfolk, Virginia, USA
| | - M. LaGatta
- Department of Infectious Diseases, University of Georgia, Athens, Georgia, USA
- Pathens Incorporated, Athens, Georgia, USA
| | - T. Gupta
- Department of Infectious Diseases, University of Georgia, Athens, Georgia, USA
| | - R. K. Karls
- Department of Infectious Diseases, University of Georgia, Athens, Georgia, USA
- Pathens Incorporated, Athens, Georgia, USA
| | - F. D. Quinn
- Department of Infectious Diseases, University of Georgia, Athens, Georgia, USA
- Pathens Incorporated, Athens, Georgia, USA
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Zha BS, Desvignes L, Fergus TJ, Cornelius A, Cheng TY, Moody DB, Ernst JD. Bacterial Strain-Dependent Dissociation of Cell Recruitment and Cell-to-Cell Spread in Early M. tuberculosis Infection. mBio 2022; 13:e0133222. [PMID: 35695454 PMCID: PMC9239178 DOI: 10.1128/mbio.01332-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 05/16/2022] [Indexed: 11/20/2022] Open
Abstract
In the initial stage of respiratory infection, Mycobacterium tuberculosis traverses from alveolar macrophages to phenotypically diverse monocyte-derived phagocytes and neutrophils in the lung parenchyma. Here, we compare the in vivo kinetics of early bacterial growth and cell-to-cell spread of two strains of M. tuberculosis: a lineage 2 strain, 4334, and the widely studied lineage 4 strain H37Rv. Using flow cytometry, live cell sorting of phenotypic subsets, and quantitation of bacteria in cells of the distinct subsets, we found that 4334 induces less leukocyte influx into the lungs but demonstrates earlier population expansion and cell-to-cell spread. The earlier spread of 4334 to recruited cells, including monocyte-derived dendritic cells, is accompanied by earlier and greater magnitude of CD4+ T cell activation. The results provide evidence that strain-specific differences in interactions with lung leukocytes can shape adaptive immune responses in vivo. IMPORTANCE Tuberculosis is a leading infectious disease killer worldwide and is caused by Mycobacterium tuberculosis. After exposure to M. tuberculosis, outcomes range from apparent elimination to active disease. Early innate immune responses may contribute to differences in outcomes, yet it is not known how bacterial strains alter the early dynamics of innate immune and T cell responses. We infected mice with distinct strains of M. tuberculosis and discovered striking differences in innate cellular recruitment, cell-to-cell spread of bacteria in the lungs, and kinetics of initiation of antigen-specific CD4 T cell responses. We also found that M. tuberculosis can spread beyond alveolar macrophages even before a large influx of inflammatory cells. These results provide evidence that distinct strains of M. tuberculosis can exhibit differential kinetics in cell-to-cell spread which is not directly linked to early recruitment of phagocytes but is subsequently linked to adaptive immune responses.
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Affiliation(s)
- B. Shoshana Zha
- Division of Pulmonary, Critical Care, Allergy and Sleep Medicine, Department of Medicine, University of California, San Francisco, California, USA
- Division of Experimental Medicine, Department of Medicine, University of California, San Francisco, California, USA
| | - Ludovic Desvignes
- Department of Medicine, New York University School of Medicine, New York, New York, USA
| | - Tawania J. Fergus
- Department of Medicine, New York University School of Medicine, New York, New York, USA
| | - Amber Cornelius
- Department of Medicine, New York University School of Medicine, New York, New York, USA
| | - Tan-Yun Cheng
- Division of Rheumatology, Immunity and Inflammation, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - D. Branch Moody
- Division of Rheumatology, Immunity and Inflammation, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Joel D. Ernst
- Division of Experimental Medicine, Department of Medicine, University of California, San Francisco, California, USA
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40
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Proteo-genetic analysis reveals clear hierarchy of ESX-1 secretion in Mycobacterium marinum. Proc Natl Acad Sci U S A 2022; 119:e2123100119. [PMID: 35671426 PMCID: PMC9214503 DOI: 10.1073/pnas.2123100119] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The ESX-1 (ESAT-6-system-1) system and the protein substrates it transports are essential for mycobacterial pathogenesis. The precise ways that ESX-1 substrates contribute to virulence remains unknown. Several known ESX-1 substrates are also required for the secretion of other proteins. We used a proteo-genetic approach to construct high-resolution dependency relationships for the roles of individual ESX-1 substrates in secretion and virulence in Mycobacterium marinum, a pathogen of humans and animals. Characterizing a collection of M. marinum strains with in-frame deletions in each of the known ESX-1 substrate genes and the corresponding complementation strains, we demonstrate that ESX-1 substrates are differentially required for ESX-1 activity and for virulence. Using isobaric-tagged proteomics, we quantified the degree of requirement of each substrate on protein secretion. We conclusively defined distinct contributions of ESX-1 substrates in protein secretion. Our data reveal a hierarchy of ESX-1 substrate secretion, which supports a model for the composition of the extracytoplasmic ESX-1 secretory machinery. Overall, our proteo-genetic analysis demonstrates discrete roles for ESX-1 substrates in ESX-1 function and secretion in M. marinum.
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41
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Zhou K, Xie L, Xu X, Sun J. Comparative Genomic Analysis of Type VII Secretion System in Streptococcus agalactiae Indicates Its Possible Sequence Type-Dependent Diversity. Front Cell Infect Microbiol 2022; 12:880943. [PMID: 35663471 PMCID: PMC9160427 DOI: 10.3389/fcimb.2022.880943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 04/21/2022] [Indexed: 11/13/2022] Open
Abstract
Streptococcus agalactiae causes sepsis and meningitis in neonates, presenting substantial clinical challenges. Type VII secretion system (T7SS), an important secretion system identified in Mycobacterium sp. and Gram-positive bacteria, was recently characterized in S. agalactiae and considered to contribute to its virulence and pathogenesis. In the present study, 128 complete genomic sequences of S. agalactiae were retrieved from GenBank to build a public dataset, and their sequences, capsular types, and clonal complexes were determined. Polymerase chain reaction (PCR) screening and genomic sequencing were conducted in an additional clinical dataset. STs and capsular types were determined using PCR. Eleven different types of T7SS were detected with similarities in gene order but differences in gene content. Strains with incomplete T7SS or lack of T7SS were also identified. Deletion, insertion, and segmentation of T7SS might be related to insertion sequences. The genetic environment of T7SS in S. agalactiae was also investigated and different patterns were identified downstream the T7SS, which were related to the diversity of T7SS putative effectors. The T7SS demonstrated possible sequence type (ST)-dependent diversity in both datasets. This work elucidated detailed genetic characteristics of T7SS and its genetic environment in S. agalactiae and further identified its possible ST-dependent diversity, which gave a clue of its mode of transmission. Further investigations are required to elucidate the underlying mechanisms and its functions.
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Affiliation(s)
- Kaixin Zhou
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China
| | - Lianyan Xie
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Department of Clinical Microbiology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Xiaogang Xu
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China
- *Correspondence: Xiaogang Xu, ; Jingyong Sun,
| | - Jingyong Sun
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Department of Clinical Microbiology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- *Correspondence: Xiaogang Xu, ; Jingyong Sun,
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42
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Song J, Chao J, Hu X, Wen X, Ding C, Li D, Zhang D, Han S, Yu X, Yan B, Jin Z, Song Y, Gonzales J, Via LE, Zhang L, Wang D. E3 Ligase FBXW7 Facilitates Mycobacterium Immune Evasion by Modulating TNF-α Expression. Front Cell Infect Microbiol 2022; 12:851197. [PMID: 35651754 PMCID: PMC9149249 DOI: 10.3389/fcimb.2022.851197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Accepted: 03/24/2022] [Indexed: 11/26/2022] Open
Abstract
Tumor necrosis factor alpha (TNF-α) is a crucial factor in the control of Mycobacterium tuberculosis (Mtb) infection. Pathogenic mycobacteria can inhibit and/or regulate host cell TNF-α production in a variety of ways to evade antituberculosis (anti-TB) immunity as well as facilitate immune escape. However, the mechanisms by which TNF-α expression in host cells is modulated to the benefit of mycobacteria is still an interesting topic and needs further study. Here, we report that macrophages infected with Mycobacterium marinum (Mm)—a close relative of Mtb—upregulated the expression of E3 ubiquitin ligase FBXW7. Specific silencing FBXW7 with small interfering RNA (siRNA) significantly elevates TNF-α expression and eventually promotes the elimination of intracellular bacteria. In turn, overexpression of FBXW7 in Raw264.7 macrophages markedly decreased TNF-α production. Furthermore, partial inhibition of FBXW7 in an Mm-infected murine model significantly reduced TNF-α tissue content, alleviated tissue damage as well as reduced the bacterial load of mouse tails. Finally, FBXW7 could decrease TNF-α in a K63-linked ubiquitin signaling dependent manner. Taken together, our study uncovered a previously unknown role of FBXW7 in regulating TNF-α dynamics during mycobacterial infection, which provides new insights into understanding the role of FBXW7 in anti-tuberculosis immunity and its related clinical significance.
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Affiliation(s)
- Jingrui Song
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang, China
- Institute of Infection and Inflammation, China Three Gorges University, Yichang, China
- Medical College, China Three Gorges University, Yichang, China
| | - Jin Chao
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang, China
- Institute of Infection and Inflammation, China Three Gorges University, Yichang, China
- Medical College, China Three Gorges University, Yichang, China
| | - Xiaohong Hu
- Institute of Infection and Inflammation, China Three Gorges University, Yichang, China
- Department of Tuberculosis, The Third People’s Hospital of Yichang, Yichang, China
| | - Xin Wen
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang, China
- Institute of Infection and Inflammation, China Three Gorges University, Yichang, China
- Medical College, China Three Gorges University, Yichang, China
| | - Cairong Ding
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang, China
- Institute of Infection and Inflammation, China Three Gorges University, Yichang, China
- Medical College, China Three Gorges University, Yichang, China
| | - Dan Li
- Institute of Infection and Inflammation, China Three Gorges University, Yichang, China
- Department of Tuberculosis, The Third People’s Hospital of Yichang, Yichang, China
| | - Ding Zhang
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang, China
- Institute of Infection and Inflammation, China Three Gorges University, Yichang, China
- Medical College, China Three Gorges University, Yichang, China
- Department of Pathology, Yichang Central People’s Hospital, Yichang, China
| | - Shanshan Han
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang, China
- Institute of Infection and Inflammation, China Three Gorges University, Yichang, China
- Medical College, China Three Gorges University, Yichang, China
| | - Xiang Yu
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang, China
- Institute of Infection and Inflammation, China Three Gorges University, Yichang, China
- Medical College, China Three Gorges University, Yichang, China
| | - Bo Yan
- Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Zhu Jin
- Institute of Infection and Inflammation, China Three Gorges University, Yichang, China
- Department of Tuberculosis, The Third People’s Hospital of Yichang, Yichang, China
| | - Yinhong Song
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang, China
- Institute of Infection and Inflammation, China Three Gorges University, Yichang, China
- Medical College, China Three Gorges University, Yichang, China
| | - Jacqueline Gonzales
- Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, and Tuberculosis Imaging Program, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Laura E. Via
- Tuberculosis Research Section, Laboratory of Clinical Immunology and Microbiology, and Tuberculosis Imaging Program, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Lu Zhang
- Engineering Research Center of Gene Technology, Ministry of Education, Department of Microbiology, School of Life Science, Fudan University, Shanghai, China
- *Correspondence: Lu Zhang, ; Decheng Wang,
| | - Decheng Wang
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, China Three Gorges University, Yichang, China
- Institute of Infection and Inflammation, China Three Gorges University, Yichang, China
- Medical College, China Three Gorges University, Yichang, China
- *Correspondence: Lu Zhang, ; Decheng Wang,
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43
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Filloux A. Bacterial protein secretion systems: Game of types. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 35536734 DOI: 10.1099/mic.0.001193] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Protein trafficking across the bacterial envelope is a process that contributes to the organisation and integrity of the cell. It is the foundation for establishing contact and exchange between the environment and the cytosol. It helps cells to communicate with one another, whether they establish symbiotic or competitive behaviours. It is instrumental for pathogenesis and for bacteria to subvert the host immune response. Understanding the formation of envelope conduits and the manifold strategies employed for moving macromolecules across these channels is a fascinating playground. The diversity of the nanomachines involved in this process logically resulted in an attempt to classify them, which is where the protein secretion system types emerged. As our knowledge grew, so did the number of types, and their rightful nomenclature started to be questioned. While this may seem a semantic or philosophical issue, it also reflects scientific rigour when it comes to assimilating findings into textbooks and science history. Here I give an overview on bacterial protein secretion systems, their history, their nomenclature and why it can be misleading for newcomers in the field. Note that I do not try to suggest a new nomenclature. Instead, I explore the reasons why naming could have escaped our control and I try to reiterate basic concepts that underlie protein trafficking cross membranes.
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Affiliation(s)
- Alain Filloux
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Imperial College London, London, SW7 2AZ, UK
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44
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Rosenberg G, Riquelme S, Prince A, Avraham R. Immunometabolic crosstalk during bacterial infection. Nat Microbiol 2022; 7:497-507. [PMID: 35365784 DOI: 10.1038/s41564-022-01080-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 02/03/2022] [Indexed: 01/22/2023]
Abstract
Following detection of bacteria, macrophages switch their metabolism from oxidative respiration through the tricarboxylic acid cycle to high-rate aerobic glycolysis. This immunometabolic shift enables pro-inflammatory and antimicrobial responses and is facilitated by the accumulation of fatty acids, tricarboxylic acid-derived metabolites and catabolism of amino acids. Recent studies have shown that these immunometabolites are co-opted by pathogens as environmental cues for expression of virulence genes. We review mechanisms by which host immunometabolites regulate bacterial pathogenicity and discuss opportunities for the development of therapeutics targeting metabolic host-pathogen crosstalk.
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Affiliation(s)
- Gili Rosenberg
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | | | - Alice Prince
- Columbia University Medical Center, New York, NY, USA.
| | - Roi Avraham
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel.
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45
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Smith CM, Baker RE, Proulx MK, Mishra BB, Long JE, Park SW, Lee HN, Kiritsy MC, Bellerose MM, Olive AJ, Murphy KC, Papavinasasundaram K, Boehm FJ, Reames CJ, Meade RK, Hampton BK, Linnertz CL, Shaw GD, Hock P, Bell TA, Ehrt S, Schnappinger D, Pardo-Manuel de Villena F, Ferris MT, Ioerger TR, Sassetti CM. Host-pathogen genetic interactions underlie tuberculosis susceptibility in genetically diverse mice. eLife 2022; 11:74419. [PMID: 35112666 PMCID: PMC8846590 DOI: 10.7554/elife.74419] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 01/27/2022] [Indexed: 11/21/2022] Open
Abstract
The outcome of an encounter with Mycobacterium tuberculosis (Mtb) depends on the pathogen’s ability to adapt to the variable immune pressures exerted by the host. Understanding this interplay has proven difficult, largely because experimentally tractable animal models do not recapitulate the heterogeneity of tuberculosis disease. We leveraged the genetically diverse Collaborative Cross (CC) mouse panel in conjunction with a library of Mtb mutants to create a resource for associating bacterial genetic requirements with host genetics and immunity. We report that CC strains vary dramatically in their susceptibility to infection and produce qualitatively distinct immune states. Global analysis of Mtb transposon mutant fitness (TnSeq) across the CC panel revealed that many virulence pathways are only required in specific host microenvironments, identifying a large fraction of the pathogen’s genome that has been maintained to ensure fitness in a diverse population. Both immunological and bacterial traits can be associated with genetic variants distributed across the mouse genome, making the CC a unique population for identifying specific host-pathogen genetic interactions that influence pathogenesis.
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Affiliation(s)
- Clare M Smith
- Department of Molecular Genetics and Microbiology, Duke University, Durham, United States
| | - Richard E Baker
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, United States
| | - Megan K Proulx
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, United States
| | - Bibhuti B Mishra
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, United States
| | - Jarukit E Long
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, United States
| | - Sae Woong Park
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, United States
| | - Ha-Na Lee
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, United States
| | - Michael C Kiritsy
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, United States
| | - Michelle M Bellerose
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, United States
| | - Andrew J Olive
- Microbiology and Molecular Genetics, Michigan State University, East Lansing, United States
| | - Kenan C Murphy
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, United States
| | - Kadamba Papavinasasundaram
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, United States
| | - Frederick J Boehm
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, United States
| | - Charlotte J Reames
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, United States
| | - Rachel K Meade
- Department of Molecular Genetics and Microbiology, Duke University, Durham, United States
| | - Brea K Hampton
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, United States
| | - Colton L Linnertz
- Department of Genetics, University of North Carolina at Chapel Hill, Morrisville, United States
| | - Ginger D Shaw
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, United States
| | - Pablo Hock
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, United States
| | - Timothy A Bell
- Department of Genetics,, University of North Carolina at Chapel Hill, Chapel Hill, United States
| | - Sabine Ehrt
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, United States
| | - Dirk Schnappinger
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, United States
| | | | - Martin T Ferris
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, United States
| | - Thomas R Ioerger
- Department of Computer Science and Engineering, Texas A&M University, College Station, United States
| | - Christopher M Sassetti
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, United States
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46
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Wang Y, Tang Y, Lin C, Zhang J, Mai J, Jiang J, Gao X, Li Y, Zhao G, Zhang L, Liu J. Crosstalk between the ancestral type VII secretion system ESX-4 and other T7SS in Mycobacterium marinum. iScience 2022; 25:103585. [PMID: 35005535 PMCID: PMC8718981 DOI: 10.1016/j.isci.2021.103585] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 10/30/2021] [Accepted: 12/06/2021] [Indexed: 12/13/2022] Open
Abstract
The type VII secretion system (T7SS) of Mycobacterium tuberculosis secretes three substrate classes: Esx, Esp, and PE/PPE proteins, that play important roles in bacterial physiology and host interaction. Five subtypes of T7SS, namely ESX-1 to ESX-5, are present in M. tb. ESX-4 is the progenitor of T7SS but its function is not understood. We investigated the ESX-4 system in Mycobacterium marinum. We show that ESX-4 of M. marinum does not secrete its cognate substrates, EsxT and EsxU, under the conditions tested. Paradoxically, the deletion of eccC4, an essential component of ESX-4, resulted in elevated secretion of protein substrates of ESX-1 and ESX-5. Consequently, the ΔeccC4 mutant was more efficient in inducing actin cytoskeleton rearrangement, which led to enhanced phagocytosis by macrophages. Our results reveal an intimate crosstalk between the progenitor of T7SS and its more recent duplication and expansion, and provide new insight into the evolution of T7SS in mycobacteria.
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Affiliation(s)
- Yuchen Wang
- Department of Microbiology, School of Life Science, Fudan University, Shanghai 200090, China.,Guizhou institute of Biotechnology, Guiyang 550025, Guizhou, China
| | - Yuting Tang
- State Key Laboratory of Genetic Engineering, School of Life Science, Institute of Genetics, Fudan University, Shanghai 200090, China
| | - Chen Lin
- State Key Laboratory of Genetic Engineering, School of Life Science, Institute of Genetics, Fudan University, Shanghai 200090, China
| | - Junli Zhang
- State Key Laboratory of Genetic Engineering, School of Life Science, Institute of Genetics, Fudan University, Shanghai 200090, China
| | - Juntao Mai
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G1M1, Canada
| | - Jun Jiang
- State Key Laboratory of Genetic Engineering, School of Life Science, Institute of Genetics, Fudan University, Shanghai 200090, China
| | - Xiaoxiao Gao
- State Key Laboratory of Genetic Engineering, School of Life Science, Institute of Genetics, Fudan University, Shanghai 200090, China
| | - Yao Li
- State Key Laboratory of Genetic Engineering, School of Life Science, Institute of Genetics, Fudan University, Shanghai 200090, China
| | - Guoping Zhao
- Department of Microbiology, School of Life Science, Fudan University, Shanghai 200090, China
| | - Lu Zhang
- Department of Microbiology, School of Life Science, Fudan University, Shanghai 200090, China.,State Key Laboratory of Genetic Engineering, School of Life Science, Institute of Genetics, Fudan University, Shanghai 200090, China.,Shanghai Engineering Research Center of Industrial Microorganisms, Shanghai 200090, China
| | - Jun Liu
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G1M1, Canada
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47
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Mekasha S, Linke D. Secretion Systems in Gram-Negative Bacterial Fish Pathogens. Front Microbiol 2022; 12:782673. [PMID: 34975803 PMCID: PMC8714846 DOI: 10.3389/fmicb.2021.782673] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 11/24/2021] [Indexed: 12/17/2022] Open
Abstract
Bacterial fish pathogens are one of the key challenges in the aquaculture industry, one of the fast-growing industries worldwide. These pathogens rely on arsenal of virulence factors such as toxins, adhesins, effectors and enzymes to promote colonization and infection. Translocation of virulence factors across the membrane to either the extracellular environment or directly into the host cells is performed by single or multiple dedicated secretion systems. These secretion systems are often key to the infection process. They can range from simple single-protein systems to complex injection needles made from dozens of subunits. Here, we review the different types of secretion systems in Gram-negative bacterial fish pathogens and describe their putative roles in pathogenicity. We find that the available information is fragmented and often descriptive, and hope that our overview will help researchers to more systematically learn from the similarities and differences between the virulence factors and secretion systems of the fish-pathogenic species described here.
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Affiliation(s)
- Sophanit Mekasha
- Section for Genetics and Evolutionary Biology, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Dirk Linke
- Section for Genetics and Evolutionary Biology, Department of Biosciences, University of Oslo, Oslo, Norway
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48
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Hinman AE, Jani C, Pringle SC, Zhang WR, Jain N, Martinot AJ, Barczak AK. Mycobacterium tuberculosis canonical virulence factors interfere with a late component of the TLR2 response. eLife 2021; 10:73984. [PMID: 34755600 PMCID: PMC8610422 DOI: 10.7554/elife.73984] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 10/29/2021] [Indexed: 01/15/2023] Open
Abstract
For many intracellular pathogens, the phagosome is the site of events and interactions that shape infection outcome. Phagosomal membrane damage, in particular, is proposed to benefit invading pathogens. To define the innate immune consequences of this damage, we profiled macrophage transcriptional responses to wild-type Mycobacterium tuberculosis (Mtb) and mutants that fail to damage the phagosomal membrane. We identified a set of genes with enhanced expression in response to the mutants. These genes represented a late component of the TLR2-dependent transcriptional response to Mtb, distinct from an earlier component that included Tnf. Expression of the later component was inherent to TLR2 activation, dependent upon endosomal uptake, and enhanced by phagosome acidification. Canonical Mtb virulence factors that contribute to phagosomal membrane damage blunted phagosome acidification and undermined the endosome-specific response. Profiling cell survival and bacterial growth in macrophages demonstrated that the attenuation of these mutants is partially dependent upon TLR2. Further, TLR2 contributed to the attenuated phenotype of one of these mutants in a murine model of infection. These results demonstrate two distinct components of the TLR2 response and identify a component dependent upon endosomal uptake as a point where pathogenic bacteria interfere with the generation of effective inflammation. This interference promotes tuberculosis (TB) pathogenesis in both macrophage and murine infection models.
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Affiliation(s)
- Amelia E Hinman
- The Ragon Institute, Massachusetts General Hospital, Cambridge, United States
| | - Charul Jani
- The Ragon Institute, Massachusetts General Hospital, Cambridge, United States
| | - Stephanie C Pringle
- The Ragon Institute, Massachusetts General Hospital, Cambridge, United States
| | - Wei R Zhang
- The Ragon Institute, Massachusetts General Hospital, Cambridge, United States
| | - Neharika Jain
- Department of Infectious Diseases and Global Health, Tufts University Cummings School of Veterinary Medicine, North Grafton, MA, United States
| | - Amanda J Martinot
- Department of Infectious Diseases and Global Health, Tufts University Cummings School of Veterinary Medicine, North Grafton, MA, United States
| | - Amy K Barczak
- The Ragon Institute, Massachusetts General Hospital, Cambridge, United States.,The Division of Infectious Diseases, Massachusetts General Hospital, Boston, United States.,Department of Medicine, Harvard Medical School, Boston, United States
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49
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Bandyopadhyay A, Saxena AK. Structural and ATPase activity analysis of nucleotide binding domain of Rv3870 enzyme of M. tuberculosis ESX-1 system. Int J Biol Macromol 2021; 189:879-889. [PMID: 34428493 DOI: 10.1016/j.ijbiomac.2021.08.130] [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: 02/10/2021] [Revised: 08/17/2021] [Accepted: 08/17/2021] [Indexed: 10/20/2022]
Abstract
The EccC enzyme of ESX-1 system contains (i) a membrane bound Rv3870 with single ATPase domain and (ii) a cytoplasmic Rv3871 with two ATPase domains and involved in secretion of ESAT6/CFP10 factor out of the cell. In current study, we have structurally and biochemically characterized the ATPase domain (442-747 residues) of Rv3870 enzyme. The ΔRv3870 eluted as oligomer (~813 kDa) from Superdex 200 (16/60) column, as identified based on molecular mass standard and dynamics light scattering. The SAXS analysis yielded a tetrameric ring envelope of ΔRv3870, quite consistent to dynamic light scattering data. The ΔRv3870 exhibited ATPase activity having kinetic parameters, Km ~ 100 ± 40 μM, kcat ~ 1.81 ± 0.27 min-1 and Vmax ~ 54.41 μM/min/mg. ATPase activity using nine ΔRv3870 mutants showed 70-91% decrease in catalytic efficiency of the enzyme. ΔRv3870 binds Rv3871 with KD ~ 484.0 ± 10.3 nM and its catalytic efficiency is enhanced ~6.7-fold in presence of Rv3871. CD data revealed the high TM ~ 82.2 ± 0.5 °C for ΔRv3870 and enhanced in presence of ATP + Mg2+, as observed in dynamics simulation on ΔRv3870 hexameric models. Overall, our structural and biochemical studies on ΔRv3870 have explained the mechanism, which will contribute in development of antivirulence inhibitors against M. tuberculosis.
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Affiliation(s)
- Arkita Bandyopadhyay
- Rm-403/440, Structural Biology Lab, School of Life Sciences, Jawaharlal Nehru University, New Delhi-67, India
| | - Ajay K Saxena
- Rm-403/440, Structural Biology Lab, School of Life Sciences, Jawaharlal Nehru University, New Delhi-67, India.
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50
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Mycobacterium tuberculosis Rv0292 Protein Peptides Could be Included in a Synthetic Anti-tuberculosis Vaccine. Int J Pept Res Ther 2021. [DOI: 10.1007/s10989-021-10292-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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