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Dechow SJ, Abramovitch RB. Targeting Mycobacterium tuberculosis pH-driven adaptation. MICROBIOLOGY (READING, ENGLAND) 2024; 170. [PMID: 38717801 DOI: 10.1099/mic.0.001458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2024]
Abstract
Mycobacterium tuberculosis (Mtb) senses and adapts to host environmental cues as part of its pathogenesis. One important cue sensed by Mtb is the acidic pH of its host niche - the macrophage. Acidic pH induces widespread transcriptional and metabolic remodelling in Mtb. These adaptations to acidic pH can lead Mtb to slow its growth and promote pathogenesis and antibiotic tolerance. Mutants defective in pH-dependent adaptations exhibit reduced virulence in macrophages and animal infection models, suggesting that chemically targeting these pH-dependent pathways may have therapeutic potential. In this review, we discuss mechanisms by which Mtb regulates its growth and metabolism at acidic pH. Additionally, we consider the therapeutic potential of disrupting pH-driven adaptations in Mtb and review the growing class of compounds that exhibit pH-dependent activity or target pathways important for adaptation to acidic pH.
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Affiliation(s)
- Shelby J Dechow
- Department of Microbiology, Genetics and Immunology, Michigan State University, East Lansing, MI 48824, USA
| | - Robert B Abramovitch
- Department of Microbiology, Genetics and Immunology, Michigan State University, East Lansing, MI 48824, USA
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2
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da Silva CV, Velikkakam T, de Oliveira ECM, Silveira ACA, de Lima Júnior JP, Uombe NPI, da Silva PHR, Borges BC. Cellular dormancy: A widespread phenomenon that perpetuates infectious diseases. J Basic Microbiol 2024; 64:e2300389. [PMID: 38064123 DOI: 10.1002/jobm.202300389] [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: 07/11/2023] [Revised: 11/05/2023] [Accepted: 11/21/2023] [Indexed: 05/03/2024]
Abstract
Under adverse environmental conditions, microorganisms are able to enter a state of cellular dormancy which consists of cell cycle arrest and interruption of multiplication. This process ensures their perpetuation in the infected host organism and enables the spread of disease. Throughout biological evolution, dormancy allowed microorganisms to persist in a harsh niche until favorable conditions for their reactivation were re-established. Here, we propose to discuss the dormancy of bacteria and protozoa pathogens focusing on the potential mechanisms and components associated with dormancy.
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Affiliation(s)
- Claudio V da Silva
- Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, Brazil
| | - Teresiama Velikkakam
- Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, Brazil
| | - Elida C M de Oliveira
- Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, Brazil
| | - Anna C A Silveira
- Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, Brazil
| | - Joed P de Lima Júnior
- Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, Brazil
| | - Nelsa P I Uombe
- Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, Brazil
| | - Paulo H R da Silva
- Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, Brazil
| | - Bruna C Borges
- Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, Brazil
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3
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Youngblom MA, Smith TM, Murray HJ, Pepperell CS. Adaptation of the Mycobacterium tuberculosis transcriptome to biofilm growth. PLoS Pathog 2024; 20:e1012124. [PMID: 38635841 PMCID: PMC11060545 DOI: 10.1371/journal.ppat.1012124] [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: 08/07/2023] [Revised: 04/30/2024] [Accepted: 03/14/2024] [Indexed: 04/20/2024] Open
Abstract
Mycobacterium tuberculosis (M. tb), the causative agent of tuberculosis (TB), is a leading global cause of death from infectious disease. Biofilms are increasingly recognized as a relevant growth form during M. tb infection and may impede treatment by enabling bacterial drug and immune tolerance. M. tb has a complicated regulatory network that has been well-characterized for many relevant disease states, including dormancy and hypoxia. However, despite its importance, our knowledge of the genes and pathways involved in biofilm formation is limited. Here we characterize the biofilm transcriptomes of fully virulent clinical isolates and find that the regulatory systems underlying biofilm growth vary widely between strains and are also distinct from regulatory programs associated with other environmental cues. We used experimental evolution to investigate changes to the transcriptome during adaptation to biofilm growth and found that the application of a uniform selection pressure resulted in loss of strain-to-strain variation in gene expression, resulting in a more uniform biofilm transcriptome. The adaptive trajectories of transcriptomes were shaped by the genetic background of the M. tb population leading to convergence on a sub-lineage specific transcriptome. We identified widespread upregulation of non-coding RNA (ncRNA) as a common feature of the biofilm transcriptome and hypothesize that ncRNA function in genome-wide modulation of gene expression, thereby facilitating rapid regulatory responses to new environments. These results reveal a new facet of the M. tb regulatory system and provide valuable insight into how M. tb adapts to new environments.
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Affiliation(s)
- Madison A. Youngblom
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Department of Medical Microbiology and Immunology, School of Medicine and Public Health, University of Madison-Wisconsin, Madison, Wisconsin, United States of America
| | - Tracy M. Smith
- Department of Medicine (Infectious Diseases), School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Holly J. Murray
- Department of Medicine (Infectious Diseases), School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Caitlin S. Pepperell
- Department of Medical Microbiology and Immunology, School of Medicine and Public Health, University of Madison-Wisconsin, Madison, Wisconsin, United States of America
- Department of Medicine (Infectious Diseases), School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
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4
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Liu R, Dang JN, Lee R, Lee JJ, Kesavamoorthy N, Ameri H, Rao N, Eoh H. Mycobacterium dormancy and antibiotic tolerance within the retinal pigment epithelium of ocular tuberculosis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.18.585612. [PMID: 38562751 PMCID: PMC10983995 DOI: 10.1101/2024.03.18.585612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Tuberculosis (TB) is a leading cause of death among infectious diseases worldwide due to latent TB infection, which is the critical step for the successful pathogenic cycle. In this stage, Mycobacterium tuberculosis resides inside the host in a dormant and antibiotic-tolerant state. Latent TB infection can lead to a multisystemic diseases because M. tuberculosis invades virtually all organs, including ocular tissues. Ocular tuberculosis (OTB) occurs when the dormant bacilli within ocular tissues reactivate, originally seeded by hematogenous spread from pulmonary TB. Timely and accurate diagnosis as well as efficient chemotherapies are crucial in preventing poor visual outcomes of OTB patients. Histological evidence suggests that retinal pigment epithelium (RPE) cells play a central role in immune privilege and in the protection from the antibiotic effects, making them an anatomical niche for invading M. tuberculosis . RPE cells exhibit high tolerance to environmental redox stresses, allowing phagocytosed M. tuberculosis bacilli to maintain viability in a dormant state. However, the microbiological and metabolic mechanisms determining the interaction between the RPE intracellular environment and phagocytosed M. tuberculosis are largely unknown. Here, liquid chromatography mass spectrometry (LC-MS) metabolomics was used to illuminate the metabolic state within RPE cells reprogrammed to harbor dormant M. tuberculosis bacilli and enhance the antibiotic tolerance. The results have led to propose a novel therapeutic option to synthetically kill the dormant M. tuberculosis inside the RPE cells by modulating the phenotypic state of M. tuberculosis , thus laying the foundation for a new, innovative regimen for treating OTB. Importance Understanding the metabolic environment within the retinal pigment epithelium (RPE) cells altered by infection with M. tuberculosis and mycobacterial dormancy is crucial to identify new therapeutic methods to cure OTB. The present study showed that RPE cellular metabolism is altered to foster intracellular M. tuberculosis to enter into the dormant and drug tolerant state, thereby blunting the efficacy of anti-TB chemotherapy. RPE cells serve as an anatomical niche as the cells protect invading bacilli from antibiotic treatment. LC-MS metabolomics of RPE cells after co-treatment with H2O2 and M. tuberculosis infection showed that intracellular environment within RPE cells is enriched with greater level of oxidative stress. The antibiotic tolerance of intracellular M. tuberculosis within RPE cells can be restored by a metabolic manipulation strategy such as co-treatment of antibiotic with the most downstream glycolysis metabolite, phosphoenolpyruvate.
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5
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Stupar M, Tan L, Kerr ED, De Voss CJ, Forde BM, Schulz BL, West NP. TcrXY is an acid-sensing two-component transcriptional regulator of Mycobacterium tuberculosis required for persistent infection. Nat Commun 2024; 15:1615. [PMID: 38388565 PMCID: PMC10883919 DOI: 10.1038/s41467-024-45343-7] [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: 05/08/2023] [Accepted: 01/22/2024] [Indexed: 02/24/2024] Open
Abstract
The ability of Mycobacterium tuberculosis (Mtb) to persist in the host complicates and prolongs tuberculosis (TB) patient chemotherapy. Here we demonstrate that a neglected two-component system (TCS) of Mtb, TcrXY, is an autoregulated acid-sensing TCS that controls a functionally diverse 70-gene regulon required for bacterial persistence. Characterisation of two representatives of this regulon, Rv3706c and Rv3705A, implicate these genes as key determinants for the survival of Mtb in vivo by serving as important effectors to mitigate redox stress at acidic pH. We show that genetic silencing of the response regulator tcrX using CRISPR interference attenuates the persistence of Mtb during chronic mouse infection and improves treatment with the two front-line anti-TB drugs, rifampicin and isoniazid. We propose that targeting TcrXY signal transduction blocks the ability of Mtb to sense and respond to acid stress, resulting in a disordered program of persistence to render the organism vulnerable to existing TB chemotherapy.
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Affiliation(s)
- Miljan Stupar
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, The University of Queensland, Brisbane, Australia
| | - Lendl Tan
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, The University of Queensland, Brisbane, Australia
| | - Edward D Kerr
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, The University of Queensland, Brisbane, Australia
| | - Christopher J De Voss
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, The University of Queensland, Brisbane, Australia
| | - Brian M Forde
- Faculty of Medicine, UQ Centre for Clinical Research, The University of Queensland, Brisbane, Australia
| | - Benjamin L Schulz
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, The University of Queensland, Brisbane, Australia
| | - Nicholas P West
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, The University of Queensland, Brisbane, Australia.
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Bull TJ, Munshi T, Lopez-Perez PM, Tran AC, Cosgrove C, Bartolf A, Menichini M, Rindi L, Parigger L, Malanovic N, Lohner K, Wang CJH, Fatima A, Martin LL, Esin S, Batoni G, Hilpert K. Specific Cationic Antimicrobial Peptides Enhance the Recovery of Low-Load Quiescent Mycobacterium tuberculosis in Routine Diagnostics. Int J Mol Sci 2023; 24:17555. [PMID: 38139385 PMCID: PMC10743970 DOI: 10.3390/ijms242417555] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 12/07/2023] [Accepted: 12/11/2023] [Indexed: 12/24/2023] Open
Abstract
The culture confirmation of Mycobacterium tuberculosis (MTB) remains the gold standard for the diagnosis of Tuberculosis (TB) with culture conversion representing proof of cure. However, over 40% of TB samples fail to isolate MTB even though many patients remain infectious due to the presence of viable non-culturable forms. Previously, we have shown that two short cationic peptides, T14D and TB08L, induce a hormetic response at low concentrations, leading to a stimulation of growth in MTB and the related animal pathogen Mycobacterium bovis (bTB). Here, we examine these peptides showing they can influence the mycobacterial membrane integrity and function through membrane potential reduction. We also show this disruption is associated with an abnormal reduction in transcriptomic signalling from specific mycobacterial membrane sensors that normally monitor the immediate cellular environment and maintain the non-growing phenotype. We observe that exposing MTB or bTB to these peptides at optimal concentrations rapidly represses signalling mechanisms maintaining dormancy phenotypes, which leads to the promotion of aerobic metabolism and conversion into a replicative phenotype. We further show a practical application of these peptides as reagents able to enhance conventional routine culture methods by stimulating mycobacterial growth. We evaluated the ability of a peptide-supplemented sample preparation and culture protocol to isolate the MTB against a gold standard routine method tested in parallel on 255 samples from 155 patients with suspected TB. The peptide enhancement increased the sample positivity rate by 46% and decreased the average time to sample positivity of respiratory/faecal sampling by seven days. The most significant improvements in isolation rates were from sputum smear-negative low-load samples and faeces. The peptide enhancement increased sampling test sensitivity by 19%, recovery in samples from patients with a previously culture-confirmed TB by 20%, and those empirically treated for TB by 21%. We conclude that sample decontamination and culture enhancement with D-enantiomer peptides offer good potential for the much-needed improvement of the culture confirmation of TB.
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Affiliation(s)
- Tim J. Bull
- Institute of Infection and Immunity, St. George’s, University of London, Cranmer Terrace, London SW17 0RE, UK (K.H.)
| | - Tulika Munshi
- Institute of Infection and Immunity, St. George’s, University of London, Cranmer Terrace, London SW17 0RE, UK (K.H.)
| | | | - Andy C. Tran
- Institute of Infection and Immunity, St. George’s, University of London, Cranmer Terrace, London SW17 0RE, UK (K.H.)
| | - Catherine Cosgrove
- St. George’s Hospital NHS Trust, Cranmer Terrace, London SW17 0RE, UK; (C.C.)
| | - Angela Bartolf
- St. George’s Hospital NHS Trust, Cranmer Terrace, London SW17 0RE, UK; (C.C.)
| | - Melissa Menichini
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy (L.R.); (S.E.); (G.B.)
| | - Laura Rindi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy (L.R.); (S.E.); (G.B.)
| | - Lena Parigger
- Institute of Molecular Biosciences, Biophysics Division, University of Graz, Humboldstrasse 50/III, 800 Graz, Austria; (L.P.); (K.L.)
| | - Nermina Malanovic
- Institute of Molecular Biosciences, Biophysics Division, University of Graz, Humboldstrasse 50/III, 800 Graz, Austria; (L.P.); (K.L.)
| | - Karl Lohner
- Institute of Molecular Biosciences, Biophysics Division, University of Graz, Humboldstrasse 50/III, 800 Graz, Austria; (L.P.); (K.L.)
| | - Carl J. H. Wang
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia (A.F.); (L.L.M.)
| | - Anam Fatima
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia (A.F.); (L.L.M.)
| | - Lisandra L. Martin
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia (A.F.); (L.L.M.)
| | - Semih Esin
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy (L.R.); (S.E.); (G.B.)
| | - Giovanna Batoni
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy (L.R.); (S.E.); (G.B.)
| | - Kai Hilpert
- Institute of Infection and Immunity, St. George’s, University of London, Cranmer Terrace, London SW17 0RE, UK (K.H.)
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Das M, Sreedharan S, Shee S, Malhotra N, Nandy M, Banerjee U, Kohli S, Rajmani RS, Chandra N, Seshasayee ASN, Laxman S, Singh A. Cysteine desulfurase (IscS)-mediated fine-tuning of bioenergetics and SUF expression prevents Mycobacterium tuberculosis hypervirulence. SCIENCE ADVANCES 2023; 9:eadh2858. [PMID: 38091389 PMCID: PMC10848736 DOI: 10.1126/sciadv.adh2858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 11/10/2023] [Indexed: 12/18/2023]
Abstract
Iron-sulfur (Fe-S) biogenesis requires multiprotein assembly systems, SUF and ISC, in most prokaryotes. M. tuberculosis (Mtb) encodes a complete SUF system, the depletion of which was bactericidal. The ISC operon is truncated to a single gene iscS (cysteine desulfurase), whose function remains uncertain. Here, we show that MtbΔiscS is bioenergetically deficient and hypersensitive to oxidative stress, antibiotics, and hypoxia. MtbΔiscS resisted killing by nitric oxide (NO). RNA sequencing indicates that IscS is important for expressing regulons of DosR and Fe-S-containing transcription factors, WhiB3 and SufR. Unlike wild-type Mtb, MtbΔiscS could not enter a stable persistent state, continued replicating in mice, and showed hypervirulence. The suf operon was overexpressed in MtbΔiscS during infection in a NO-dependent manner. Suppressing suf expression in MtbΔiscS either by CRISPR interference or upon infection in inducible NO-deficient mice arrests hypervirulence. Together, Mtb redesigned the ISC system to "fine-tune" the expression of SUF machinery for establishing persistence without causing detrimental disease in the host.
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Affiliation(s)
- Mayashree Das
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
- Centre for Infectious Disease Research, Indian Institute of Science, Bangalore 560012, India
| | - Sreesa Sreedharan
- Institute for Stem Cell Science and Regenerative Medicine, Bangalore 560065, India
- School of Chemical and Biotechnology, (SASTRA)-Deemed to be University, Thanjavur 613401, India
| | - Somnath Shee
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
- Centre for Infectious Disease Research, Indian Institute of Science, Bangalore 560012, India
| | - Nitish Malhotra
- National Centre for Biological Sciences (NCBS), Tata Institute of Fundamental Research (TIFR), Bangalore 560065, India
| | - Meghna Nandy
- National Centre for Biological Sciences (NCBS), Tata Institute of Fundamental Research (TIFR), Bangalore 560065, India
| | - Ushashi Banerjee
- Department of Biochemistry, Indian Institute of Science, Bangalore 560012, India
| | - Sakshi Kohli
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
- Centre for Infectious Disease Research, Indian Institute of Science, Bangalore 560012, India
| | - Raju S. Rajmani
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560012, India
| | - Nagasuma Chandra
- Department of Biochemistry, Indian Institute of Science, Bangalore 560012, India
| | - Aswin Sai Narain Seshasayee
- National Centre for Biological Sciences (NCBS), Tata Institute of Fundamental Research (TIFR), Bangalore 560065, India
| | - Sunil Laxman
- Institute for Stem Cell Science and Regenerative Medicine, Bangalore 560065, India
| | - Amit Singh
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India
- Centre for Infectious Disease Research, Indian Institute of Science, Bangalore 560012, India
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8
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McIntyre S, Warner J, Rush C, Vanderven HA. Antibodies as clinical tools for tuberculosis. Front Immunol 2023; 14:1278947. [PMID: 38162666 PMCID: PMC10755875 DOI: 10.3389/fimmu.2023.1278947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Accepted: 11/27/2023] [Indexed: 01/03/2024] Open
Abstract
Tuberculosis (TB) is a leading cause of morbidity and mortality worldwide. Global research efforts to improve TB control are hindered by insufficient understanding of the role that antibodies play in protective immunity and pathogenesis. This impacts knowledge of rational and optimal vaccine design, appropriate diagnostic biomarkers, and development of therapeutics. Traditional approaches for the prevention and diagnosis of TB may be less efficacious in high prevalence, remote, and resource-poor settings. An improved understanding of the immune response to the causative agent of TB, Mycobacterium tuberculosis (Mtb), will be crucial for developing better vaccines, therapeutics, and diagnostics. While memory CD4+ T cells and cells and cytokine interferon gamma (IFN-g) have been the main identified correlates of protection in TB, mounting evidence suggests that other types of immunity may also have important roles. TB serology has identified antibodies and functional characteristics that may help diagnose Mtb infection and distinguish between different TB disease states. To date, no serological tests meet the World Health Organization (WHO) requirements for TB diagnosis, but multiplex assays show promise for improving the sensitivity and specificity of TB serodiagnosis. Monoclonal antibody (mAb) therapies and serum passive infusion studies in murine models of TB have also demonstrated some protective outcomes. However, animal models that better reflect the human immune response to Mtb are necessary to fully assess the clinical utility of antibody-based TB prophylactics and therapeutics. Candidate TB vaccines are not designed to elicit an Mtb-specific antibody response, but evidence suggests BCG and novel TB vaccines may induce protective Mtb antibodies. The potential of the humoral immune response in TB monitoring and control is being investigated and these studies provide important insight into the functional role of antibody-mediated immunity against TB. In this review, we describe the current state of development of antibody-based clinical tools for TB, with a focus on diagnostic, therapeutic, and vaccine-based applications.
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Affiliation(s)
- Sophie McIntyre
- Biomedical Sciences and Molecular Biology, College of Public Health, Medical and Veterinary Sciences, James Cook University, Douglas, QLD, Australia
- Australian Institute of Tropical Health and Medicine, James Cook University, Douglas, QLD, Australia
| | - Jeffrey Warner
- Biomedical Sciences and Molecular Biology, College of Public Health, Medical and Veterinary Sciences, James Cook University, Douglas, QLD, Australia
- Australian Institute of Tropical Health and Medicine, James Cook University, Douglas, QLD, Australia
| | - Catherine Rush
- Biomedical Sciences and Molecular Biology, College of Public Health, Medical and Veterinary Sciences, James Cook University, Douglas, QLD, Australia
- Australian Institute of Tropical Health and Medicine, James Cook University, Douglas, QLD, Australia
| | - Hillary A. Vanderven
- Biomedical Sciences and Molecular Biology, College of Public Health, Medical and Veterinary Sciences, James Cook University, Douglas, QLD, Australia
- Australian Institute of Tropical Health and Medicine, James Cook University, Douglas, QLD, Australia
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, University of Melbourne, Parkville, VIC, Australia
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9
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Gopi Reji J, K Edison L, Raghunandanan S, Pushparajan AR, Kurthkoti K, Ajay Kumar R. Rv1255c, a dormancy-related transcriptional regulator of TetR family in Mycobacterium tuberculosis, enhances isoniazid tolerance in Mycobacterium smegmatis. J Antibiot (Tokyo) 2023; 76:720-727. [PMID: 37821540 DOI: 10.1038/s41429-023-00661-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 08/29/2023] [Accepted: 09/12/2023] [Indexed: 10/13/2023]
Abstract
Mycobacterium tuberculosis is exposed to diverse stresses inside the host during dormancy. Meanwhile, many metabolic and transcriptional regulatory changes occur, resulting in physiological modifications that help M. tuberculosis to adapt to these stresses. The same physiological changes also cause antibiotic tolerance in dormant M. tuberculosis. However, the transcriptional regulatory mechanism of antibiotic tolerance during dormancy remains unclear. Here, we showed that the expression of Rv1255c, an uncharacterised member of the tetracycline repressor family of transcriptional regulators, is upregulated during different stresses and hypoxia-induced dormancy. Antibiotic tolerance and efflux activities of Mycobacterium smegmatis constitutively expressing Rv1255c were analysed, and interestingly, it showed increased isoniazid tolerance and efflux activity. The intrabacterial isoniazid concentrations were found to be low in M. smegmatis expressing Rv1255c. Moreover, orthologs of the M. tuberculosis katG, gene of the enzyme which activates the first-line prodrug isoniazid, are overexpressed in this strain. Structural analysis of isoforms of KatG enzymes in M. smegmatis identified major amino acid substitutions associated with isoniazid resistance. Thus, we showed that Rv1255c helps M. smegmatis tolerate isoniazid by orchestrating drug efflux machinery. In addition, we showed that Rv1255c also causes overexpression of katG isoform in M. smegmatis which has amino acid substitutions as found in isoniazid-resistant katG in M. tuberculosis.
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Affiliation(s)
- Jijimole Gopi Reji
- Mycobacterium Research Laboratory, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, 695014, India
| | - Lakshmi K Edison
- Mycobacterium Research Laboratory, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, 695014, India
| | - Sajith Raghunandanan
- Mycobacterium Research Laboratory, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, 695014, India
| | - Akhil Raj Pushparajan
- Mycobacterium Research Laboratory, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, 695014, India
| | - Krishna Kurthkoti
- Mycobacterium Research Laboratory, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, 695014, India
| | - Ramakrsihnan Ajay Kumar
- Mycobacterium Research Laboratory, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, 695014, India.
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10
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Werman J, Chen YC, Yuan T, Yang X, Sampson NS. A Chemoproteomic Approach to Elucidate the Mechanism of Action of 6-Azasteroids with Unique Activity in Mycobacteria. ACS Infect Dis 2023; 9:1993-2004. [PMID: 37774412 PMCID: PMC10580313 DOI: 10.1021/acsinfecdis.3c00296] [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: 06/26/2023] [Indexed: 10/01/2023]
Abstract
By illuminating key 6-azasteroid-protein interactions in both Mycobacterium tuberculosis (Mtb) and the closely related model organism Mycobacterium marinum (Mm), we sought to improve the antimycobacterial potency of 6-azasteroids and further our understanding of the mechanisms responsible for their potentiation of the antituberculosis drug bedaquiline. We selected a newly developed 6-azasteroid analog and an analog reported previously (ACS Infect. Dis. 2019, 5 (7), 1239-1251) to study their phenotypic effects on Mtb and Mm, both alone and in combination with bedaquiline. The 6-azasteroid analog, 17β-[N-(4-trifluoromethoxy-diphenylmethyl)carbamoyl]-6-propyl-azaandrostan-3-one, robustly potentiated bedaquiline-mediated antimycobacterial activity, with a nearly 8-fold reduction in Mm bedaquiline minimal inhibitory concentration (85 nM alone versus 11 nM with 20 μM 6-azasteroid). This analog displayed minimal inhibitory activity against recombinant mycobacterial 3β-hydroxysteroid dehydrogenase, a previously identified target of several 6-azasteroids. Dose-dependent potentiation of bedaquiline by this analog reduced mycobacterial intracellular ATP levels and impeded the ability of Mtb to neutralize exogenous oxidative stress in culture. We developed two 6-azasteroid photoaffinity probes to investigate azasteroid-protein interactions in Mm whole cells. Using bottom-up mass spectrometric profiling of the cross-linked proteins, we identified eight potential Mm/Mtb protein targets for 6-azasteroids. The nature of these potential targets indicates that proteins related to oxidative stress resistance play a key role in the BDQ-potentiating activity of azasteroids and highlights the potential impact of inhibition of these targets on the generation of drug sensitivity.
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Affiliation(s)
- Joshua
M. Werman
- Department
of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States
| | - Yu-Ching Chen
- Program
in Biochemistry and Structural Biology, Stony Brook University, Stony
Brook, New York 11794-5215, United States
| | - Tianao Yuan
- Department
of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States
| | - Xinxin Yang
- Department
of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States
| | - Nicole S. Sampson
- Department
of Chemistry, Stony Brook University, Stony Brook, New York 11794-3400, United States
- Department
of Chemistry, University of Rochester, Rochester, New York 14627-0216, United States
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11
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Sugandhi S, Rajmane V, Taunk K, Jadhav S, Nema V, Rapole S, Mande SC. The role of thioredoxin proteins in Mycobacterium tuberculosis probed by proteome-wide target profiling. Biochem Biophys Rep 2023; 35:101512. [PMID: 37521372 PMCID: PMC10371808 DOI: 10.1016/j.bbrep.2023.101512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 06/27/2023] [Accepted: 07/06/2023] [Indexed: 08/01/2023] Open
Abstract
Mycobacterium tuberculosis encounters diverse microenvironments, including oxidative assault (ROS and RNS), when it attempts to establish itself within its human host. Therefore, redox sensory and regulation processes are assumed significant importance, as these are essential processes for M. tuberculosis to survive under these hostile conditions. M. tuberculosis contains thioredoxin system to maintain redox homeostasis, which establish a balance between the thiol/dithiol couple. Still very less is known about it. In the present study, we attempted to capture the targets of all the M. tuberculosis thioredoxin proteins (viz., TrxB and TrxC) and a thioredoxin-like protein, NrdH, under aerobic and hypoxic conditions by performing thioredoxin trapping chromatography followed by mass spectrometry. We found that TrxC captured the maximum number of targets in both the physiological conditions and most of the targets of TrxB and NrdH showing overlap with targets of TrxC, indicating that TrxC acts as main thioredoxin. Further the PANTHER classification system provides involvement of targets in various metabolic processes and Gene Ontology analysis suggests that glutamine biosynthetic process and Fe-S cluster biosynthesis are the most enriched processes in the target list of TrxC and TrxB respectively. Also, we suggest that the thioredoxin system might play an important role under hypoxia by targeting those proteins which are responsible to sense and maintain hypoxic conditions. Furthermore, our studies establish a link between TrxB and iron-sulfur cluster biogenesis in M. tuberculosis. Ultimately, these findings open a new direction to target the thioredoxin system for screening new anti-mycobacterial drug targets.
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Affiliation(s)
- Sapna Sugandhi
- National Centre for Cell Science, Savitribai Phule Pune University Campus, Pune, India
| | - Vyankatesh Rajmane
- National Centre for Cell Science, Savitribai Phule Pune University Campus, Pune, India
| | - Khushman Taunk
- National Centre for Cell Science, Savitribai Phule Pune University Campus, Pune, India
| | - Sushama Jadhav
- Division of Molecular Biology, ICMR-National AIDS Research Institute, Pune, India
| | - Vijay Nema
- Division of Molecular Biology, ICMR-National AIDS Research Institute, Pune, India
| | - Srikanth Rapole
- National Centre for Cell Science, Savitribai Phule Pune University Campus, Pune, India
| | - Shekhar C. Mande
- National Centre for Cell Science, Savitribai Phule Pune University Campus, Pune, India
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12
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Shee S, Veetil RT, Mohanraj K, Das M, Malhotra N, Bandopadhyay D, Beig H, Birua S, Niphadkar S, Nagarajan SN, Sinha VK, Thakur C, Rajmani RS, Chandra N, Laxman S, Singh M, Samal A, Seshasayee AN, Singh A. Biosensor-integrated transposon mutagenesis reveals rv0158 as a coordinator of redox homeostasis in Mycobacterium tuberculosis. eLife 2023; 12:e80218. [PMID: 37642294 PMCID: PMC10501769 DOI: 10.7554/elife.80218] [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: 05/12/2022] [Accepted: 08/25/2023] [Indexed: 08/31/2023] Open
Abstract
Mycobacterium tuberculosis (Mtb) is evolutionarily equipped to resist exogenous reactive oxygen species (ROS) but shows vulnerability to an increase in endogenous ROS (eROS). Since eROS is an unavoidable consequence of aerobic metabolism, understanding how Mtb manages eROS levels is essential yet needs to be characterized. By combining the Mrx1-roGFP2 redox biosensor with transposon mutagenesis, we identified 368 genes (redoxosome) responsible for maintaining homeostatic levels of eROS in Mtb. Integrating redoxosome with a global network of transcriptional regulators revealed a hypothetical protein (Rv0158) as a critical node managing eROS in Mtb. Disruption of rv0158 (rv0158 KO) impaired growth, redox balance, respiration, and metabolism of Mtb on glucose but not on fatty acids. Importantly, rv0158 KO exhibited enhanced growth on propionate, and the Rv0158 protein directly binds to methylmalonyl-CoA, a key intermediate in propionate catabolism. Metabolite profiling, ChIP-Seq, and gene-expression analyses indicate that Rv0158 manages metabolic neutralization of propionate toxicity by regulating the methylcitrate cycle. Disruption of rv0158 enhanced the sensitivity of Mtb to oxidative stress, nitric oxide, and anti-TB drugs. Lastly, rv0158 KO showed poor survival in macrophages and persistence defect in mice. Our results suggest that Rv0158 is a metabolic integrator for carbon metabolism and redox balance in Mtb.
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Affiliation(s)
- Somnath Shee
- Department of Microbiology and Cell Biology, Indian Institute of Science BangaloreBangaloreIndia
- Centre for Infectious Disease Research, Indian Institute of Science BangaloreKarnatakaIndia
| | | | - Karthikeyan Mohanraj
- The Institute of Mathematical Sciences, A CI of Homi Bhabha National InstituteChennaiIndia
| | - Mayashree Das
- Department of Microbiology and Cell Biology, Indian Institute of Science BangaloreBangaloreIndia
- Centre for Infectious Disease Research, Indian Institute of Science BangaloreKarnatakaIndia
| | | | | | - Hussain Beig
- Department of Microbiology and Cell Biology, Indian Institute of Science BangaloreBangaloreIndia
- Centre for Infectious Disease Research, Indian Institute of Science BangaloreKarnatakaIndia
| | - Shalini Birua
- Department of Microbiology and Cell Biology, Indian Institute of Science BangaloreBangaloreIndia
- Centre for Infectious Disease Research, Indian Institute of Science BangaloreKarnatakaIndia
| | - Shreyas Niphadkar
- Institute for Stem Cell Science and Regenerative MedicineBangaloreIndia
| | - Sathya Narayanan Nagarajan
- Department of Microbiology and Cell Biology, Indian Institute of Science BangaloreBangaloreIndia
- Centre for Infectious Disease Research, Indian Institute of Science BangaloreKarnatakaIndia
| | - Vikrant Kumar Sinha
- Molecular Biophysics Unit, Indian Institute of Science BangaloreBangaloreIndia
| | - Chandrani Thakur
- Department of Biochemistry, Indian Institute of Science BangaloreBangaloreIndia
| | - Raju S Rajmani
- Centre for Infectious Disease Research, Indian Institute of Science BangaloreKarnatakaIndia
| | - Nagasuma Chandra
- Department of Biochemistry, Indian Institute of Science BangaloreBangaloreIndia
| | - Sunil Laxman
- Institute for Stem Cell Science and Regenerative MedicineBangaloreIndia
| | - Mahavir Singh
- Molecular Biophysics Unit, Indian Institute of Science BangaloreBangaloreIndia
| | - Areejit Samal
- The Institute of Mathematical Sciences, A CI of Homi Bhabha National InstituteChennaiIndia
| | | | - Amit Singh
- Department of Microbiology and Cell Biology, Indian Institute of Science BangaloreBangaloreIndia
- Centre for Infectious Disease Research, Indian Institute of Science BangaloreKarnatakaIndia
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13
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Nelson SJ, Williams JT, Buglino JA, Nambi S, Lojek LJ, Glickman MS, Ioerger TR, Sassetti CM. The Rip1 intramembrane protease contributes to iron and zinc homeostasis in Mycobacterium tuberculosis. mSphere 2023; 8:e0038922. [PMID: 37318217 PMCID: PMC10449499 DOI: 10.1128/msphere.00389-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 04/28/2023] [Indexed: 06/16/2023] Open
Abstract
Mycobacterium tuberculosis is exposed to a variety of stresses during a chronic infection, as the immune system simultaneously produces bactericidal compounds and starves the pathogen of essential nutrients. The intramembrane protease, Rip1, plays an important role in the adaptation to these stresses, at least partially by the cleavage of membrane-bound transcriptional regulators. Although Rip1 is known to be critical for surviving copper intoxication and nitric oxide exposure, these stresses do not fully account for the regulatory protein's essentiality during infection. In this work, we demonstrate that Rip1 is also necessary for growth in low-iron and low-zinc conditions, similar to those imposed by the immune system. Using a newly generated library of sigma factor mutants, we show that the known regulatory target of Rip1, SigL, shares this defect. Transcriptional profiling under iron-limiting conditions supported the coordinated activity of Rip1 and SigL and demonstrated that the loss of these proteins produces an exaggerated iron starvation response. These observations demonstrate that Rip1 coordinates several aspects of metal homeostasis and suggest that a Rip1- and SigL-dependent pathway is necessary to thrive in the iron-deficient environments encountered during infection. IMPORTANCE Metal homeostasis represents a critical point of interaction between the mammalian immune system and potential pathogens. While the host attempts to intoxicate microbes with high concentrations of copper or starve the invader of iron and zinc, successful pathogens have acquired mechanisms to overcome these defenses. Our work identifies a regulatory pathway consisting of the Rip1 intramembrane protease and the sigma factor, SigL, that is essential for the important human pathogen, Mycobacterium tuberculosis, to grow in low-iron or low-zinc conditions such as those encountered during infection. In conjunction with Rip1's known role in resisting copper toxicity, our work implicates this protein as a critical integration point that coordinates the multiple metal homeostatic systems required for this pathogen to survive in host tissue.
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Affiliation(s)
- Samantha J. Nelson
- Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - John T. Williams
- Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - John A. Buglino
- Immunology Program, Sloan Kettering Institute, New York City, New York, USA
| | - Subhalaxmi Nambi
- Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - Lisa J. Lojek
- Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | | | - Thomas R. Ioerger
- Department of Computer Science and Engineering, Texas A&M University, College Station, Texas, USA
| | - Christopher M. Sassetti
- Department of Microbiology and Physiological Systems, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
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14
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Youngblom MA, Smith TM, Pepperell CS. Adaptation of the Mycobacterium tuberculosis transcriptome to biofilm growth. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.18.549484. [PMID: 37503306 PMCID: PMC10370045 DOI: 10.1101/2023.07.18.549484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Mycobacterium tuberculosis ( M. tb ), the causative agent of tuberculosis (TB), is a leading global cause of death from infectious disease. Biofilms are increasingly recognized as a relevant growth form during M. tb infection and may impede treatment by enabling bacterial drug and immune tolerance. M. tb has a complicated regulatory network that has been well-characterized for many relevant disease states, including dormancy and hypoxia. However, despite its importance, our knowledge of the genes and pathways involved in biofilm formation is limited. Here we characterize the biofilm transcriptomes of fully virulent clinical isolates and find that the regulatory systems underlying biofilm growth vary widely between strains and are also distinct from regulatory programs associated with other environmental cues. We used experimental evolution to investigate changes to the transcriptome during adaptation to biofilm growth and found that the application of a uniform selection pressure resulted in loss of strain-to-strain variation in gene expression, resulting in a more uniform biofilm transcriptome. The adaptive trajectories of transcriptomes were shaped by the genetic background of the M. tb population leading to convergence on a sub-lineage specific transcriptome. We identified widespread upregulation of non-coding RNA (ncRNA) as a common feature of the biofilm transcriptome and hypothesize that ncRNA function in genome-wide modulation of gene expression, thereby facilitating rapid regulatory responses to new environments. These results reveal a new facet of the M. tb regulatory system and provide valuable insight into how M. tb adapts to new environments. Importance Understanding mechanisms of resistance and tolerance in Mycobacterium tuberculosis ( M. tb ) can help us develop new treatments that capitalize on M. tb 's vulnerabilities. Here we used transcriptomics to study both the regulation of biofilm formation in clinical isolates as well as how those regulatory systems adapt to new environments. We find that closely related clinical populations have diverse strategies for growth under biofilm conditions, and that genetic background plays a large role in determining the trajectory of evolution. These results have implications for future treatment strategies that may be informed by our knowledge of the evolutionary constraints on strain(s) from an individual infection. This work provides new information about the mechanisms of biofilm formation in M. tb and outlines a framework for population level approaches for studying bacterial adaptation.
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15
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Zhang Y, Xu JC, Hu ZD, Fan XY. Advances in protein subunit vaccines against tuberculosis. Front Immunol 2023; 14:1238586. [PMID: 37654500 PMCID: PMC10465801 DOI: 10.3389/fimmu.2023.1238586] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 07/25/2023] [Indexed: 09/02/2023] Open
Abstract
Tuberculosis (TB), also known as the "White Plague", is caused by Mycobacterium tuberculosis (Mtb). Before the COVID-19 epidemic, TB had the highest mortality rate of any single infectious disease. Vaccination is considered one of the most effective strategies for controlling TB. Despite the limitations of the Bacille Calmette-Guérin (BCG) vaccine in terms of protection against TB among adults, it is currently the only licensed TB vaccine. Recently, with the evolution of bioinformatics and structural biology techniques to screen and optimize protective antigens of Mtb, the tremendous potential of protein subunit vaccines is being exploited. Multistage subunit vaccines obtained by fusing immunodominant antigens from different stages of TB infection are being used both to prevent and to treat TB. Additionally, the development of novel adjuvants is compensating for weaknesses of immunogenicity, which is conducive to the flourishing of subunit vaccines. With advances in the development of animal models, preclinical vaccine protection assessments are becoming increasingly accurate. This review summarizes progress in the research of protein subunit TB vaccines during the past decades to facilitate the further optimization of protein subunit vaccines that may eradicate TB.
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Affiliation(s)
- Ying Zhang
- Shanghai Public Health Clinical Center, Shanghai Institute of Infectious Disease and Biosecurity, Fudan University, Shanghai, China
| | - Jin-chuan Xu
- Shanghai Public Health Clinical Center, Shanghai Institute of Infectious Disease and Biosecurity, Fudan University, Shanghai, China
| | - Zhi-dong Hu
- Shanghai Public Health Clinical Center, Shanghai Institute of Infectious Disease and Biosecurity, Fudan University, Shanghai, China
- TB Center, Shanghai Emerging and Re-emerging Infectious Disease Institute, Fudan University, Shanghai, China
| | - Xiao-yong Fan
- Shanghai Public Health Clinical Center, Shanghai Institute of Infectious Disease and Biosecurity, Fudan University, Shanghai, China
- TB Center, Shanghai Emerging and Re-emerging Infectious Disease Institute, Fudan University, Shanghai, China
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16
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Stiens J, Tan YY, Joyce R, Arnvig KB, Kendall SL, Nobeli I. Using a whole genome co-expression network to inform the functional characterisation of predicted genomic elements from Mycobacterium tuberculosis transcriptomic data. Mol Microbiol 2023; 119:381-400. [PMID: 36924313 DOI: 10.1111/mmi.15055] [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: 11/18/2022] [Revised: 03/08/2023] [Accepted: 03/09/2023] [Indexed: 03/18/2023]
Abstract
A whole genome co-expression network was created using Mycobacterium tuberculosis transcriptomic data from publicly available RNA-sequencing experiments covering a wide variety of experimental conditions. The network includes expressed regions with no formal annotation, including putative short RNAs and untranslated regions of expressed transcripts, along with the protein-coding genes. These unannotated expressed transcripts were among the best-connected members of the module sub-networks, making up more than half of the 'hub' elements in modules that include protein-coding genes known to be part of regulatory systems involved in stress response and host adaptation. This data set provides a valuable resource for investigating the role of non-coding RNA, and conserved hypothetical proteins, in transcriptomic remodelling. Based on their connections to genes with known functional groupings and correlations with replicated host conditions, predicted expressed transcripts can be screened as suitable candidates for further experimental validation.
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Affiliation(s)
- Jennifer Stiens
- Institute of Structural and Molecular Biology, Biological Sciences, Birkbeck, University of London, London, UK
| | - Yen Yi Tan
- Institute of Structural and Molecular Biology, Biological Sciences, Birkbeck, University of London, London, UK
| | - Rosanna Joyce
- Institute of Structural and Molecular Biology, Biological Sciences, Birkbeck, University of London, London, UK
| | - Kristine B Arnvig
- Division of Biosciences, Institute of Structural and Molecular Biology, University College London, London, UK
| | - Sharon L Kendall
- Royal Veterinary College, Centre for Emerging, Endemic and Exotic Diseases, Pathobiology and Population Sciences, Hatfield, UK
| | - Irene Nobeli
- Institute of Structural and Molecular Biology, Biological Sciences, Birkbeck, University of London, London, UK
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17
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Simcox BS, Tomlinson BR, Shaw LN, Rohde KH. Mycobacterium abscessus DosRS two-component system controls a species-specific regulon required for adaptation to hypoxia. Front Cell Infect Microbiol 2023; 13:1144210. [PMID: 36968107 PMCID: PMC10034137 DOI: 10.3389/fcimb.2023.1144210] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 02/15/2023] [Indexed: 03/12/2023] Open
Abstract
Mycobacterium abscessus (Mab), an emerging opportunistic pathogen, predominantly infects individuals with underlying pulmonary diseases such as cystic fibrosis (CF). Current treatment outcomes for Mab infections are poor due to Mab's inherent antibiotic resistance and unique host interactions that promote phenotypic tolerance and hinder drug access. The hypoxic, mucus-laden airways in the CF lung and antimicrobial phagosome within macrophages represent hostile niches Mab must overcome via alterations in gene expression for survival. Regulatory mechanisms important for the adaptation and long-term persistence of Mab within the host are poorly understood, warranting further genetic and transcriptomics study of this emerging pathogen. DosRS Mab , a two-component signaling system (TCS), is one proposed mechanism utilized to subvert host defenses and counteract environmental stress such as hypoxia. The homologous TCS of Mycobacterium tuberculosis (Mtb), DosRS Mtb , is known to induce a ~50 gene regulon in response to hypoxia, carbon monoxide (CO) and nitric oxide (NO) in vitro and in vivo. Previously, a small DosR Mab regulon was predicted using bioinformatics based on DosR Mtb motifs however, the role and regulon of DosRS Mab in Mab pathogenesis have yet to be characterized in depth. To address this knowledge gap, our lab generated a Mab dosRS knockout strain (MabΔdosRS) to investigate differential gene expression, and phenotype in an in vitro hypoxia model of dormancy. qRT-PCR and lux reporter assays demonstrate Mab_dosR and 6 predicted downstream genes are induced in hypoxia. In addition, RNAseq revealed induction of a much larger hypoxia response comprised of >1000 genes, including 127 differentially expressed genes in a dosRS mutant strain. Deletion of DosRS Mab led to attenuated growth under low oxygen conditions, a shift in morphotype from smooth to rough, and down-regulation of 216 genes. This study provides the first look at the global transcriptomic response of Mab to low oxygen conditions encountered in the airways of CF patients and within macrophage phagosomes. Our data also demonstrate the importance of DosRS Mab for adaptation of Mab to hypoxia, highlighting a distinct regulon (compared to Mtb) that is significantly larger than previously described, including both genes conserved across mycobacteria as well as Mab-specific genes.
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Affiliation(s)
- Breven S. Simcox
- Division of Immunology and Pathogenesis, Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, United States
| | - Brooke R. Tomlinson
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL, United States
| | - Lindsey N. Shaw
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL, United States
| | - Kyle H. Rohde
- Division of Immunology and Pathogenesis, Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, United States
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18
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He C, Li B, Gong Z, Huang S, Liu X, Wang J, Xie J, Shi T. Polyphosphate kinase 1 is involved in formation, the morphology and ultramicrostructure of biofilm of Mycobacterium smegmatis and its survivability in macrophage. Heliyon 2023; 9:e14513. [PMID: 36967885 PMCID: PMC10034464 DOI: 10.1016/j.heliyon.2023.e14513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 03/06/2023] [Accepted: 03/09/2023] [Indexed: 03/17/2023] Open
Abstract
The most unique characteristic of Mycobacterium tuberculosis is persistence in the human host, and the biofilm formation is related to the persistance. Polyphosphate (polyP) kinase 1 (PPK1) is conserved in Mycobacteria and is responsible for polyP synthesis. polyP is a chain molecule linked by high-energy phosphate bonds, which is considered to play a very important role in bacterial persistence. However, the relationship of PPK1 and mycobacterial biofilm formation is still adequately unclear. In current study, ppk1-deficient mutant (MT), ppk1-complemented (CT) and wild-type strains of M. smegmatis mc2 155 were used to investigate the formation, morphology and ultramicrostructure of the biofilm and to analyze the lipid levels and susceptibility to vancomycin antibiotic. And then WT, MT and CT strains were used to infect macrophages and to analyze the expression levels of various inflammatory factors, respectively. We found that PPK1 was required for M. smegmatis polyP production in vivo and polyP deficiency not only attenuated the biofilm formation, but also altered the phenotype and ultramicrostructure of the biofilm and reduced the cell lipid composition (except for C16.1 and C17.1, most of the fatty acid components from C8-C24). Moreover, the ppk1-deficient mutant was also significantly more sensitive to vancomycin which targets the cell wall, and its ability to survive in macrophages was decreased, which was related to the change of the expression level of inflammatory factors in macrophage. This study demonstrates that the PPK1 can affect the biofilm structure through affecting the content of short chain fatty acid and promote intracellular survival of M. smegmatis by altering the expression of inflammatory factors. These findings establish a basis for investigating the role of PPK1 in the persistence of M. tuberculosis, and provide clues for treating latent infection of M. tuberculosis with PPK1 as a potential drug target.
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Affiliation(s)
- Cailin He
- Medical School of Hubei Minzu University, Enshi, 445000, China
| | - Bo Li
- Medical School of Hubei Minzu University, Enshi, 445000, China
| | - Zhen Gong
- Institute of Modern Biopharmaceuticals, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Sheng Huang
- Medical School of Hubei Minzu University, Enshi, 445000, China
- Institute of Selenium Science and Industry of Hubei Minzu University, Enshi, 445000, China
| | - Xu Liu
- Medical School of Hubei Minzu University, Enshi, 445000, China
- Institute of Selenium Science and Industry of Hubei Minzu University, Enshi, 445000, China
| | - Jiajun Wang
- Medical School of Hubei Minzu University, Enshi, 445000, China
| | - Jianping Xie
- Institute of Modern Biopharmaceuticals, School of Life Sciences, Southwest University, Chongqing, 400715, China
- Corresponding author. Institute of Modern Biopharmaceuticals, School of Life Sciences, Southwest University, Chongqing, 400715, China.
| | - Tingyu Shi
- Medical School of Hubei Minzu University, Enshi, 445000, China
- Hubei Key Laboratory of Biological Resources Protection and Utilization, Enshi, 445000, China
- Institute of Selenium Science and Industry of Hubei Minzu University, Enshi, 445000, China
- Corresponding author. Medical School of Hubei Minzu University, Enshi, 445000, China.
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19
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Kaur K, Sharma S, Abhishek S, Kaur P, Saini UC, Dhillon MS, Karakousis PC, Verma I. Metabolic switching and cell wall remodelling of Mycobacterium tuberculosis during bone tuberculosis. J Infect 2023; 86:134-146. [PMID: 36549425 DOI: 10.1016/j.jinf.2022.12.014] [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: 04/13/2022] [Revised: 12/12/2022] [Accepted: 12/13/2022] [Indexed: 12/24/2022]
Abstract
OBJECTIVES Bone tuberculosis (TB) is the third most common types of extrapulmonary tuberculosis. It is critical to understand mycobacterial adaptive strategies within bone lesions to identify mycobacterial factors that may have role in disease pathogenesis. METHODS Whole genome microarray was used to characterize the in-vivo transcriptome of Mycobacterium tuberculosis (M.tb) within bone TB specimens. Mycobacterial virulent proteins were identified by bioinformatic software. An in vitro osteoblast cell line model was used to study the role of these proteins in bone TB pathogenesis. RESULTS 914 mycobacterial genes were significantly overexpressed and 1688 were repressed in bone TB specimens. Pathway analysis of differentially expressed genes demonstrated a non-replicative and hypometabolic state of M.tb, reinforcement of the mycobacterial cell wall and induction of DNA damage repair responses, suggesting possible survival strategies of M.tb within bone. Bioinformatics mining of microarray data led to identification of five virulence proteins. The genes encoding these proteins were also upregulated in the in vitro MC3T3 osteoblast cell line model of bone TB. Further, exposure of osteoblast cells to two of these virulence proteins (Rv1046c and Rv3663c) significantly inhibited osteoblast differentiation. CONCLUSION M.tb alters its transcriptome to establish infection in bone by upregulating certain virulence genes which play a key role in disturbing bone homeostasis.
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Affiliation(s)
- Khushpreet Kaur
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Sumedha Sharma
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Sudhanshu Abhishek
- Department of Biochemistry and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Prabhdeep Kaur
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Uttam Chand Saini
- Department of Orthopaedics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Mandeep Singh Dhillon
- Department of Orthopaedics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Petros C Karakousis
- Centers for Tuberculosis Research and Systems Approaches for Infectious Diseases, School of Medicine, Johns Hopkins University, Baltimore, MD, United States
| | - Indu Verma
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
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20
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Cioetto-Mazzabò L, Boldrin F, Beauvineau C, Speth M, Marina A, Namouchi A, Segafreddo G, Cimino M, Favre-Rochex S, Balasingham S, Trastoy B, Munier-Lehmann H, Griffiths G, Gicquel B, Guerin M, Manganelli R, Alonso-Rodríguez N. SigH stress response mediates killing of Mycobacterium tuberculosis by activating nitronaphthofuran prodrugs via induction of Mrx2 expression. Nucleic Acids Res 2022; 51:144-165. [PMID: 36546765 PMCID: PMC9841431 DOI: 10.1093/nar/gkac1173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 11/17/2022] [Accepted: 12/02/2022] [Indexed: 12/24/2022] Open
Abstract
The emergence of drug-resistant Mycobacterium tuberculosis strains highlights the need to discover anti-tuberculosis drugs with novel mechanisms of action. Here we discovered a mycobactericidal strategy based on the prodrug activation of selected chemical derivatives classified as nitronaphthofurans (nNFs) mediated by the coordinated action of the sigH and mrx2 genes. The transcription factor SigH is a key regulator of an extensive transcriptional network that responds to oxidative, nitrosative, and heat stresses in M. tuberculosis. The nNF action induced the SigH stress response which in turn induced the mrx2 overexpression. The nitroreductase Mrx2 was found to activate nNF prodrugs, killing replicating, non-replicating and intracellular forms of M. tuberculosis. Analysis of SigH DNA sequences obtained from spontaneous nNF-resistant M. tuberculosis mutants suggests disruption of SigH binding to the mrx2 promoter site and/or RNA polymerase core, likely promoting the observed loss of transcriptional control over Mrx2. Mutations found in mrx2 lead to structural defects in the thioredoxin fold of the Mrx2 protein, significantly impairing the activity of the Mrx2 enzyme against nNFs. Altogether, our work brings out the SigH/Mrx2 stress response pathway as a promising target for future drug discovery programs.
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Affiliation(s)
| | | | - Claire Beauvineau
- Chemical Library Institut Curie/CNRS, CNRS UMR9187, INSERM U1196 and CNRS UMR3666, INSERM U1193, Université Paris-Saclay, Orsay 91405, France
| | - Martin Speth
- Department Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, Oslo 0371, Norway
| | - Alberto Marina
- Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio 48160 Spain
| | - Amine Namouchi
- Génétique Mycobactérienne, Institute Pasteur, Paris 75015, France,Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences, University of Oslo, Oslo 0371, Norway
| | - Greta Segafreddo
- Department of Molecular Medicine, University of Padova, Padova 35122, Italy
| | - Mena Cimino
- Génétique Mycobactérienne, Institute Pasteur, Paris 75015, France
| | | | | | - Beatriz Trastoy
- Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio 48160 Spain,Structural Glycobiology Laboratory, Biocruces Bizkaia Health Research Institute, Cruces University Hospital, Bizkaia 48903, Spain
| | - Hélène Munier-Lehmann
- Département de Biologie Structurale et Chimie, Institut Pasteur, CNRS UMR3523, Université de Paris, Paris 75015, France
| | - Gareth Griffiths
- Department Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, Oslo 0371, Norway
| | - Brigitte Gicquel
- Génétique Mycobactérienne, Institute Pasteur, Paris 75015, France,Department of Tuberculosis Control and Prevention, Shenzhen Nanshan Centre for Chronic Disease Control, Shenzhen 518054, China
| | - Marcelo E Guerin
- Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio 48160 Spain,Structural Glycobiology Laboratory, Biocruces Bizkaia Health Research Institute, Cruces University Hospital, Bizkaia 48903, Spain,IKERBASQUE, Basque Foundation for Science, Bilbao 48009, Spain
| | - Riccardo Manganelli
- Correspondence may also be addressed to Riccardo Manganelli. Tel: +39 049 827 2366; Fax: +39 049 827 2355;
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Mukomura J, Nonaka H, Sato H, Kishimoto M, Arai M, Kotoku N. Anti-Mycobacterial N-(2-Arylethyl)quinolin-3-amines Inspired by Marine Sponge-Derived Alkaloid. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27248701. [PMID: 36557834 PMCID: PMC9781020 DOI: 10.3390/molecules27248701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/03/2022] [Accepted: 12/06/2022] [Indexed: 12/13/2022]
Abstract
The synthesis and evaluation of simplified analogs of marine sponge-derived alkaloid 3-(phenethylamino)demethyl(oxy)aaptamine were performed to develop novel anti-mycobacterial substances. Ring truncation of the tricyclic benzo[de][1,6]-naphthyridine skeleton effectively weakened the cytotoxicity of the natural product, and the resulting AC-ring analog exhibited good anti-mycobacterial activity. A structure-activity relationship (SAR) study, synthesizing and evaluating some analogs, demonstrated the specificity and importance of the N-(2-arylethyl)quinolin-3-amine skeleton as a promising scaffold for anti-mycobacterial lead compounds.
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Affiliation(s)
- Junya Mukomura
- College of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577, Japan
| | - Hiroki Nonaka
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Hiromasa Sato
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Maho Kishimoto
- College of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577, Japan
| | - Masayoshi Arai
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Naoyuki Kotoku
- College of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577, Japan
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan
- Correspondence: ; Tel.: +81-77-561-4920
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22
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Mycobacterium tuberculosis Dormancy: How to Fight a Hidden Danger. Microorganisms 2022; 10:microorganisms10122334. [PMID: 36557586 PMCID: PMC9784227 DOI: 10.3390/microorganisms10122334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 11/20/2022] [Accepted: 11/22/2022] [Indexed: 11/29/2022] Open
Abstract
Both latent and active TB infections are caused by a heterogeneous population of mycobacteria, which includes actively replicating and dormant bacilli in different proportions. Dormancy substantially affects M. tuberculosis drug tolerance and TB clinical management due to a significant decrease in the metabolic activity of bacilli, which leads to the complexity of both the diagnosis and the eradication of bacilli. Most diagnostic approaches to latent infection deal with a subpopulation of active M. tuberculosis, underestimating the contribution of dormant bacilli and leading to limited success in the fight against latent TB. Moreover, active TB appears not only as a primary form of infection but can also develop from latent TB, when resuscitation from dormancy is followed by bacterial multiplication, leading to disease progression. To win against latent infection, the identification of the Achilles' heel of dormant M. tuberculosis is urgently needed. Regulatory mechanisms and metabolic adaptation to growth arrest should be studied using in vitro and in vivo models that adequately imitate latent TB infection in macroorganisms. Understanding the mechanisms underlying M. tuberculosis dormancy and resuscitation may provide clues to help control latent infection, reduce disease severity in patients, and prevent pathogen transmission in the population.
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23
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Alebouyeh S, Weinrick B, Achkar JM, García MJ, Prados-Rosales R. Feasibility of novel approaches to detect viable Mycobacterium tuberculosis within the spectrum of the tuberculosis disease. Front Med (Lausanne) 2022; 9:965359. [PMID: 36072954 PMCID: PMC9441758 DOI: 10.3389/fmed.2022.965359] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 08/05/2022] [Indexed: 11/13/2022] Open
Abstract
Tuberculosis (TB) is a global disease caused by Mycobacterium tuberculosis (Mtb) and is manifested as a continuum spectrum of infectious states. Both, the most common and clinically asymptomatic latent tuberculosis infection (LTBI), and the symptomatic disease, active tuberculosis (TB), are at opposite ends of the spectrum. Such binary classification is insufficient to describe the existing clinical heterogeneity, which includes incipient and subclinical TB. The absence of clinically TB-related symptoms and the extremely low bacterial burden are features shared by LTBI, incipient and subclinical TB states. In addition, diagnosis relies on cytokine release after antigenic T cell stimulation, yet several studies have shown that a high proportion of individuals with immunoreactivity never developed disease, suggesting that they were no longer infected. LTBI is estimated to affect to approximately one fourth of the human population and, according to WHO data, reactivation of LTBI is the main responsible of TB cases in developed countries. Assuming the drawbacks associated to the current diagnostic tests at this part of the disease spectrum, properly assessing individuals at real risk of developing TB is a major need. Further, it would help to efficiently design preventive treatment. This quest would be achievable if information about bacterial viability during human silent Mtb infection could be determined. Here, we have evaluated the feasibility of new approaches to detect viable bacilli across the full spectrum of TB disease. We focused on methods that specifically can measure host-independent parameters relying on the viability of Mtb either by its direct or indirect detection.
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Affiliation(s)
- Sogol Alebouyeh
- Department of Preventive Medicine and Public Health and Microbiology, Autonoma University of Madrid, Madrid, Spain
| | | | - Jacqueline M. Achkar
- Departments of Medicine, Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Maria J. García
- Department of Preventive Medicine and Public Health and Microbiology, Autonoma University of Madrid, Madrid, Spain
- *Correspondence: Maria J. García,
| | - Rafael Prados-Rosales
- Department of Preventive Medicine and Public Health and Microbiology, Autonoma University of Madrid, Madrid, Spain
- Rafael Prados-Rosales,
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24
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Mahatha AC, Banerjee SK, Ghosh A, Lata S, Saha S, Basu J, Kundu M. A systems approach to decipher a role of transcription factor RegX3 in the adaptation of Mycobacterium tuberculosis to hypoxic stress. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 35980355 DOI: 10.1099/mic.0.001229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Two-component systems (TCSs) are required for the ability of Mycobacterium tuberculosis to respond to stress. The paired TCS, SenX3-RegX3 is known to respond to phosphate starvation and acid stress. The other stress conditions under which RegX3 is required for M. tuberculosis to mount an appropriate response, remain incompletely understood. Here we have employed genome-wide microarray profiling to compare gene expression in a ΔregX3 mutant with the wild-type under phosphate stress, in order to gain information on the probable RegX3 regulon. We pulled out a set of 128 hypoxia-associated genes, which could potentially be regulated by RegX3, by overlapping the gene set downregulated at least twofold in ΔregX3 with the gene set reported in the literature to be associated with the response to hypoxia. We identified potential RegX3 binding inverted repeats at the loci of 41 of these genes, in silico. We also observed that ΔregX3 was attenuated in terms of its ability to withstand hypoxia, and this was reversed upon complementation with regX3, corroborating a role of RegX3 in the response of M. tuberculosis to hypoxia. We validated the binding of RegX3 at the upstream regions of a selected set of these genes. Electrophoretic mobility shift assays (EMSAs) confirmed that RegX3 binds to the upstream regions of the hypoxia-associated genes Rv3334, whiB7, Rv0195, Rv0196 and Rv1960c. Gene expression analyses showed that the expression of these genes is regulated by RegX3 under hypoxia. We also show that the expression of whiB7, Rv3334 and Rv0195 in macrophage-grown M. tuberculosis, is dependent on RegX3. Finally, we show that attenuation of survival of ΔregX3 under hypoxia is partly reversed upon overexpression of either Rv0195 or Rv3334, suggesting that the RegX3-Rv0195 and the RegX3-Rv3334 axis are involved in the adaptation of M. tuberculosis to a hypoxic environment.
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Affiliation(s)
- Amar Chandra Mahatha
- Department of Chemistry, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009, India
| | - Srijon Kaushik Banerjee
- Department of Chemistry, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009, India.,Present address: Department of Microbiology and Molecular Genetics, School of Medicine, University of Pittsburgh, 450 Technology Drive, Pittsburgh, PA 15217, USA
| | - Abhirupa Ghosh
- Division of Bioinformatics, Bose Institute, P-1/12 C.I.T. Scheme VIIM, Kolkata 700054, India
| | - Suruchi Lata
- Department of Chemistry, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009, India
| | - Sudipto Saha
- Division of Bioinformatics, Bose Institute, P-1/12 C.I.T. Scheme VIIM, Kolkata 700054, India
| | - Joyoti Basu
- Department of Chemistry, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009, India
| | - Manikuntala Kundu
- Department of Chemistry, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata 700009, India
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25
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Sevalkar RR, Glasgow JN, Pettinati M, Marti MA, Reddy VP, Basu S, Alipour E, Kim-Shapiro DB, Estrin DA, Lancaster JR, Steyn AJC. Mycobacterium tuberculosis DosS binds H 2S through its Fe 3+ heme iron to regulate the DosR dormancy regulon. Redox Biol 2022; 52:102316. [PMID: 35489241 PMCID: PMC9062744 DOI: 10.1016/j.redox.2022.102316] [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: 02/28/2022] [Revised: 04/06/2022] [Accepted: 04/16/2022] [Indexed: 01/14/2023] Open
Abstract
Mycobacterium tuberculosis (Mtb) senses and responds to host-derived gasotransmitters NO and CO via heme-containing sensor kinases DosS and DosT and the response regulator DosR. Hydrogen sulfide (H2S) is an important signaling molecule in mammals, but its role in Mtb physiology is unclear. We have previously shown that exogenous H2S can modulate expression of genes in the Dos dormancy regulon via an unknown mechanism(s). Here, we test the hypothesis that Mtb senses and responds to H2S via the DosS/T/R system. Using UV-Vis and EPR spectroscopy, we show that H2S binds directly to the ferric (Fe3+) heme of DosS (KDapp = 5.30 μM) but not the ferrous (Fe2+) form. No interaction with DosT(Fe2+-O2) was detected. We found that the binding of sulfide can slowly reduce the DosS heme iron to the ferrous form. Steered Molecular Dynamics simulations show that H2S, and not the charged HS- species, can enter the DosS heme pocket. We also show that H2S increases DosS autokinase activity and subsequent phosphorylation of DosR, and H2S-mediated increases in Dos regulon gene expression is lost in Mtb lacking DosS. Finally, we demonstrate that physiological levels of H2S in macrophages can induce DosR regulon genes via DosS. Overall, these data reveal a novel mechanism whereby Mtb senses and responds to a third host gasotransmitter, H2S, via DosS(Fe3+). These findings highlight the remarkable plasticity of DosS and establish a new paradigm for how bacteria can sense multiple gasotransmitters through a single heme sensor kinase.
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Affiliation(s)
- Ritesh R Sevalkar
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Joel N Glasgow
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA.
| | - Martín Pettinati
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE), Buenos Aires, Argentina
| | - Marcelo A Marti
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Biológica, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Química Biológica (IQUIBICEN), Buenos Aires, Argentina
| | - Vineel P Reddy
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Swati Basu
- Department of Physics, Wake Forest University, Winston-Salem, NC, USA
| | - Elmira Alipour
- Department of Physics, Wake Forest University, Winston-Salem, NC, USA
| | | | - Dario A Estrin
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Inorgánica, Analítica y Química Física, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE), Buenos Aires, Argentina
| | - Jack R Lancaster
- Department of Pharmacology & Chemical Biology, Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Adrie J C Steyn
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA; Centers for AIDS Research and Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL, USA; Africa Health Research Institute, University of KwaZulu-Natal, Durban, South Africa.
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26
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Mansour M, Giudice E, Xu X, Akarsu H, Bordes P, Guillet V, Bigot DJ, Slama N, D'urso G, Chat S, Redder P, Falquet L, Mourey L, Gillet R, Genevaux P. Substrate recognition and cryo-EM structure of the ribosome-bound TAC toxin of Mycobacterium tuberculosis. Nat Commun 2022; 13:2641. [PMID: 35552387 PMCID: PMC9098466 DOI: 10.1038/s41467-022-30373-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 04/27/2022] [Indexed: 11/16/2022] Open
Abstract
Toxins of toxin-antitoxin systems use diverse mechanisms to control bacterial growth. Here, we focus on the deleterious toxin of the atypical tripartite toxin-antitoxin-chaperone (TAC) system of Mycobacterium tuberculosis, whose inhibition requires the concerted action of the antitoxin and its dedicated SecB-like chaperone. We show that the TAC toxin is a bona fide ribonuclease and identify exact cleavage sites in mRNA targets on a transcriptome-wide scale in vivo. mRNA cleavage by the toxin occurs after the second nucleotide of the ribosomal A-site codon during translation, with a strong preference for CCA codons in vivo. Finally, we report the cryo-EM structure of the ribosome-bound TAC toxin in the presence of native M. tuberculosis cspA mRNA, revealing the specific mechanism by which the TAC toxin interacts with the ribosome and the tRNA in the P-site to cleave its mRNA target. Toxin-antitoxin systems are widespread in bacteria. Here the authors present structures of M. tuberculosis HigBTAC alone and bound to the ribosome in the presence of native cspA mRNA, shedding light on its mechanism of translation inhibition.
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Affiliation(s)
- Moise Mansour
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Emmanuel Giudice
- Institut de Génétique et Développement de Rennes (IGDR), UMR6290, Université de Rennes, CNRS, Rennes, France
| | - Xibing Xu
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Hatice Akarsu
- Department of Biology, University of Fribourg & Swiss Institute of Bioinformatics, Fribourg, Switzerland.,Institute of Veterinary Bacteriology, University of Bern, Bern, Switzerland
| | - Patricia Bordes
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Valérie Guillet
- Institut de Pharmacologie et de Biologie Structurale, IPBS, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Donna-Joe Bigot
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France.,Institut de Pharmacologie et de Biologie Structurale, IPBS, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Nawel Slama
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Gaetano D'urso
- Institut de Génétique et Développement de Rennes (IGDR), UMR6290, Université de Rennes, CNRS, Rennes, France
| | - Sophie Chat
- Institut de Génétique et Développement de Rennes (IGDR), UMR6290, Université de Rennes, CNRS, Rennes, France
| | - Peter Redder
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Laurent Falquet
- Department of Biology, University of Fribourg & Swiss Institute of Bioinformatics, Fribourg, Switzerland
| | - Lionel Mourey
- Institut de Pharmacologie et de Biologie Structurale, IPBS, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Reynald Gillet
- Institut de Génétique et Développement de Rennes (IGDR), UMR6290, Université de Rennes, CNRS, Rennes, France.
| | - Pierre Genevaux
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France.
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27
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Mycobacterium tuberculosis Transcription Factor EmbR Regulates the Expression of Key Virulence Factors That Aid in Ex Vivo and In Vivo Survival. mBio 2022; 13:e0383621. [PMID: 35471080 PMCID: PMC9239209 DOI: 10.1128/mbio.03836-21] [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: 11/20/2022] Open
Abstract
Mycobacterium tuberculosis encodes ~200 transcription factors that modulate gene expression under different microenvironments in the host. Even though high-throughput chromatin immunoprecipitation sequencing and transcriptome sequencing (RNA-seq) studies have identified the regulatory network for ~80% of transcription factors, many transcription factors remain uncharacterized. EmbR is one such transcription factor whose in vivo regulon and biological function are yet to be elucidated. Previous in vitro studies suggested that phosphorylation of EmbR by PknH upregulates the embCAB operon. Using a gene replacement mutant of embR, we investigated its role in modulating cellular morphology, antibiotic resistance, and survival in the host. Contrary to the prevailing hypothesis, under normal growth conditions, EmbR is neither phosphorylated nor impacted by ethambutol resistance through the regulation of the embCAB operon. The embR deletion mutant displayed attenuated M. tuberculosis survival in vivo. RNA-seq analysis suggested that EmbR regulates operons involved in the secretion pathway, lipid metabolism, virulence, and hypoxia, including well-known hypoxia-inducible genes devS and hspX. Lipidome analysis revealed that EmbR modulates levels of all lysophospholipids, several phospholipids, and M. tuberculosis-specific lipids, which is more pronounced under hypoxic conditions. We found that the EmbR mutant is hypersusceptible to hypoxic stress, and RNA sequencing performed under hypoxic conditions indicated that EmbR majorly regulates genes involved in response to acidic pH, hypoxia, and fatty acid metabolism. We observed condition-specific phosphorylation of EmbR, which contributes to EmbR-mediated transcription of several essential genes, ensuring enhanced survival. Collectively, the study establishes EmbR as a key modulator of hypoxic response that facilitates mycobacterial survival in the host.
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28
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A century of attempts to develop an effective tuberculosis vaccine: Why they failed? Int Immunopharmacol 2022; 109:108791. [PMID: 35487086 DOI: 10.1016/j.intimp.2022.108791] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 04/18/2022] [Accepted: 04/18/2022] [Indexed: 11/23/2022]
Abstract
Tuberculosis (TB) remains a major global health problem despite widespread use of the Bacillus BCG vaccine. This situation is worsened by co-infection with HIV, and the development of multidrug-resistant Mycobacterium tuberculosis (Mtb) strains. Thus, novel vaccine candidates and improved vaccination strategies are urgently needed in order to reduce the incidence of TB and even to eradicate TB by 2050. Over the last few decades, 23 novel TB vaccines have entered into clinical trials, more than 13 new vaccines have reached various stages of preclinical development, and more than 50 potential candidates are in the discovery stage as next-generation vaccines. Nevertheless, why has a century of attempts to introduce an effective TB vaccine failed? Who should be blamed -scientists, human response, or Mtb strategies? Literature review reveals that the elimination of latent or active Mtb infections in a given population seems to be an epigenetic process. With a better understanding of the connections between bacterial infections and gene expression conditions in epigenetic events, opportunities arise in designing protective vaccines or therapeutic agents, particularly as epigenetic processes can be reversed. Therefore, this review provides a brief overview of different approaches towards novel vaccination strategies and the mechanisms underlying these approaches.
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29
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Chattopadhyay G, Bhasin M, Ahmed S, Gosain TP, Ganesan S, Das S, Thakur C, Chandra N, Singh R, Varadarajan R. Functional and Biochemical Characterization of the MazEF6 Toxin-Antitoxin System of Mycobacterium tuberculosis. J Bacteriol 2022; 204:e0005822. [PMID: 35357163 PMCID: PMC9053165 DOI: 10.1128/jb.00058-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Accepted: 03/07/2022] [Indexed: 12/15/2022] Open
Abstract
The Mycobacterium tuberculosis genome harbors nine toxin-antitoxin (TA) systems that are members of the mazEF family, unlike other prokaryotes, which have only one or two. Although the overall tertiary folds of MazF toxins are predicted to be similar, it is unclear how they recognize structurally different RNAs and antitoxins with divergent sequence specificity. Here, we have expressed and purified the individual components and complex of the MazEF6 TA system from M. tuberculosis. Size exclusion chromatography-multiangle light scattering (SEC-MALS) was performed to determine the oligomerization status of the toxin, antitoxin, and the complex in different stoichiometric ratios. The relative stabilities of the proteins were determined by nano-differential scanning fluorimetry (nano-DSF). Microscale thermophoresis (MST) and yeast surface display (YSD) were performed to measure the relative affinities between the cognate toxin-antitoxin partners. The interaction between MazEF6 complexes and cognate promoter DNA was also studied using MST. Analysis of paired-end RNA sequencing data revealed that the overexpression of MazF6 resulted in differential expression of 323 transcripts in M. tuberculosis. Network analysis was performed to identify the nodes from the top-response network. The analysis of mRNA protection ratios resulted in identification of putative MazF6 cleavage site in its native host, M. tuberculosis. IMPORTANCE M. tuberculosis harbors a large number of type II toxin-antitoxin (TA) systems, the exact roles for most of which are unclear. Prior studies have reported that overexpression of several of these type II toxins inhibits bacterial growth and contributes to the formation of drug-tolerant populations in vitro. To obtain insights into M. tuberculosis MazEF6 type II TA system function, we determined stability, oligomeric states, and binding affinities of cognate partners with each other and with their promoter operator DNA. Using RNA-seq data obtained from M. tuberculosis overexpression strains, we have identified putative MazF6 cleavage sites and targets in its native, cellular context.
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Affiliation(s)
| | - Munmun Bhasin
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, Karnataka, India
| | - Shahbaz Ahmed
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, Karnataka, India
| | - Tannu Priya Gosain
- Tuberculosis Research Laboratory, Translational Health Science and Technology Institute, NCR Biotech Science Cluster, Faridabad, Haryana, India
| | - Srivarshini Ganesan
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, Tamil Nadu, India
| | - Sayan Das
- Tuberculosis Research Laboratory, Translational Health Science and Technology Institute, NCR Biotech Science Cluster, Faridabad, Haryana, India
| | - Chandrani Thakur
- Department of Biochemistry, Indian Institute of Science, Bangalore, Karnataka, India
| | - Nagasuma Chandra
- Department of Biochemistry, Indian Institute of Science, Bangalore, Karnataka, India
| | - Ramandeep Singh
- Tuberculosis Research Laboratory, Translational Health Science and Technology Institute, NCR Biotech Science Cluster, Faridabad, Haryana, India
| | - Raghavan Varadarajan
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, Karnataka, India
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30
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Ma R, Farrell D, Gonzalez G, Browne JA, Nakajima C, Suzuki Y, Gordon SV. The TbD1 Locus Mediates a Hypoxia-Induced Copper Response in Mycobacterium bovis. Front Microbiol 2022; 13:817952. [PMID: 35495699 PMCID: PMC9048740 DOI: 10.3389/fmicb.2022.817952] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 02/10/2022] [Indexed: 12/12/2022] Open
Abstract
The Mycobacterium tuberculosis complex (MTBC) contains the causative agents of tuberculosis (TB) in mammals. The archetypal members of the MTBC, Mycobacterium tuberculosis and Mycobacterium bovis, cause human tuberculosis and bovine tuberculosis, respectively. Although M. tuberculosis and M. bovis share over 99.9% genome identity, they show distinct host adaptation for humans and animals; hence, while the molecular basis of host adaptation is encoded in their genomes, the mechanistic basis of host tropism is still unclear. Exploration of the in vitro phenotypic consequences of known genetic difference between M. bovis and M. tuberculosis offers one route to explore genotype–phenotype links that may play a role in host adaptation. The TbD1 (“Mycobacterium tuberculosis deletion 1 region”) locus encompasses the mmpS6 and mmpL6 genes. TbD1 is absent in M. tuberculosis “modern” lineages (Lineages 2, 3, and 4) but present in “ancestral” M. tuberculosis (Lineages 1 and 7), Mycobacterium africanum lineages (Lineages 5 and 6), newly identified M. tuberculosis lineages (Lineages 8 and 9), and animal adapted strains, such as M. bovis. The function of TbD1 has previously been investigated in M. tuberculosis, where conflicting data has emerged on the role of TbD1 in sensitivity to oxidative stress, while the underlying mechanistic basis of such a phenotype is unclear. In this study, we aimed to shed further light on the role of the TbD1 locus by exploring its function in M. bovis. Toward this, we constructed an M. bovis TbD1 knockout (ΔTbD1) strain and conducted comparative transcriptomics to define global gene expression profiles of M. bovis wild-type (WT) and the ΔTbD1 strains under in vitro culture conditions (rolling and standing cultures). This analysis revealed differential induction of a hypoxia-driven copper response in WT and ΔTbD1 strains. In vitro phenotypic assays demonstrated that the deletion of TbD1 sensitized M. bovis to H2O2 and hypoxia-specific copper toxicity. Our study provides new information on the function of the TbD1 locus in M. bovis and its role in stress responses in the MTBC.
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Affiliation(s)
- Ruoyao Ma
- UCD School of Veterinary Medicine, University College Dublin, Dublin, Ireland
| | - Damien Farrell
- UCD School of Veterinary Medicine, University College Dublin, Dublin, Ireland
| | - Gabriel Gonzalez
- Hokkaido University International Institute for Zoonosis Control, Sapporo, Japan
| | - John A. Browne
- UCD School of Agriculture and Food Science, University College Dublin, Dublin, Ireland
| | - Chie Nakajima
- Hokkaido University International Institute for Zoonosis Control, Sapporo, Japan
- Division of Bioresources, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Yasuhiko Suzuki
- Hokkaido University International Institute for Zoonosis Control, Sapporo, Japan
- Division of Bioresources, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Stephen V. Gordon
- UCD School of Veterinary Medicine, University College Dublin, Dublin, Ireland
- Hokkaido University International Institute for Zoonosis Control, Sapporo, Japan
- UCD Conway Institute, University College Dublin, Dublin, Ireland
- *Correspondence: Stephen V. Gordon,
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Environment dependent expression of mycobacterium hormone sensitive lipases: expression pattern under ex-vivo and individual in-vitro stress conditions in M. tuberculosis H37Ra. Mol Biol Rep 2022; 49:4583-4593. [PMID: 35301657 DOI: 10.1007/s11033-022-07305-4] [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: 10/30/2021] [Revised: 01/27/2022] [Accepted: 02/24/2022] [Indexed: 10/18/2022]
Abstract
BACKGROUND Hormone-sensitive lipase (HSL) is a neutral lipase capable of hydrolysing various kinds of lipids. In comparison to single human Hormone Sensitive Lipase (hHSL), that is induced under nutritional stress, twelve serine hydrolases are annotated as HSL in Mycobacterium tuberculosis (mHSL). Mycobacterium is exposed to multiple stresses inside the host. Therefore, the present study was carried out to investigate if mHSL are also expressed under stress condition and if there is any correlation between various stress conditions and expression pattern of mHSL. METHODS AND RESULTS The expression pattern of mHSL under different environmental conditions (in-vitro and ex-vivo) were studied using qRT-PCR in M. tuberculosis H37Ra strain with 16 S rRNA as internal control. Out of 12, only two genes (lipU and lipY) were expressed at very low level in mid log phase culture under aerobic conditions, while 9 genes were expressed at stationary phase of growth. Ten mHSLs were expressed post-infection under ex-vivo conditions in time dependent manner. LipH and lipQ did not express at any time point under ex-vivo condition. The relative expression of most of the genes under individual stress was much higher than observed in ex-vivo conditions. The expression pattern of genes varied with change in stress condition. CONCLUSIONS Different sets of mHSL genes were expressed under different individual stress conditions pointing towards the requirement of different mHSL to combat different stress conditions. Overall, most of the mHSLs have demonstrated stress dependent expression pointing towards their role in intracellular survival of mycobacteria.
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Martínez-Pérez A, Estévez O, González-Fernández Á. Contribution and Future of High-Throughput Transcriptomics in Battling Tuberculosis. Front Microbiol 2022; 13:835620. [PMID: 35283833 PMCID: PMC8908424 DOI: 10.3389/fmicb.2022.835620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 01/25/2022] [Indexed: 11/13/2022] Open
Abstract
While Tuberculosis (TB) infection remains a serious challenge worldwide, big data and “omic” approaches have greatly contributed to the understanding of the disease. Transcriptomics have been used to tackle a wide variety of queries including diagnosis, treatment evolution, latency and reactivation, novel target discovery, vaccine response or biomarkers of protection. Although a powerful tool, the elevated cost and difficulties in data interpretation may hinder transcriptomics complete potential. Technology evolution and collaborative efforts among multidisciplinary groups might be key in its exploitation. Here, we discuss the main fields explored in TB using transcriptomics, and identify the challenges that need to be addressed for a real implementation in TB diagnosis, prevention and therapy.
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Affiliation(s)
- Amparo Martínez-Pérez
- Biomedical Research Center (CINBIO), Universidade de Vigo, Vigo, Spain.,Hospital Álvaro Cunqueiro, Galicia Sur Health Research Institute (IIS-GS), Vigo, Spain
| | - Olivia Estévez
- Biomedical Research Center (CINBIO), Universidade de Vigo, Vigo, Spain.,Hospital Álvaro Cunqueiro, Galicia Sur Health Research Institute (IIS-GS), Vigo, Spain
| | - África González-Fernández
- Biomedical Research Center (CINBIO), Universidade de Vigo, Vigo, Spain.,Hospital Álvaro Cunqueiro, Galicia Sur Health Research Institute (IIS-GS), Vigo, Spain
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33
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Khabibullina NF, Kutuzova DM, Burmistrova IA, Lyadova IV. The Biological and Clinical Aspects of a Latent Tuberculosis Infection. Trop Med Infect Dis 2022; 7:tropicalmed7030048. [PMID: 35324595 PMCID: PMC8955876 DOI: 10.3390/tropicalmed7030048] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 03/04/2022] [Accepted: 03/04/2022] [Indexed: 01/22/2023] Open
Abstract
Tuberculosis (TB), caused by bacilli from the Mycobacterium tuberculosis complex, remains a serious global public health problem, representing one of the main causes of death from infectious diseases. About one quarter of the world’s population is infected with Mtb and has a latent TB infection (LTBI). According to the World Health Organization (WHO), an LTBI is characterized by a lasting immune response to Mtb antigens without any TB symptoms. Current LTBI diagnoses and treatments are based on this simplified definition, although an LTBI involves a broad range of conditions, including when Mtb remains in the body in a persistent form and the immune response cannot be detected. The study of LTBIs has progressed in recent years; however, many biological and medical aspects of an LTBI are still under discussion. This review focuses on an LTBI as a broad spectrum of states, both of the human body, and of Mtb cells. The problems of phenotypic insusceptibility, diagnoses, chemoprophylaxis, and the necessity of treatment are discussed. We emphasize the complexity of an LTBI diagnosis and its treatment due to its ambiguous nature. We consider alternative ways of differentiating an LTBI from active TB, as well as predicting TB reactivation based on using mycobacterial “latency antigens” for interferon gamma release assay (IGRA) tests and the transcriptomic analysis of human blood cells.
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Ma Z, Holland AA, Szlamkowicz I, Anagnostopoulos V, Caldas Nogueira ML, Caranto JD, Davidson VL. The hemerythrin-like diiron protein from Mycobacterium kansasii is a nitric oxide peroxidase. J Biol Chem 2022; 298:101696. [PMID: 35150744 PMCID: PMC8913304 DOI: 10.1016/j.jbc.2022.101696] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 02/03/2022] [Accepted: 02/04/2022] [Indexed: 11/30/2022] Open
Abstract
The hemerythrin-like protein from Mycobacterium kansasii (Mka HLP) is a member of a distinct class of oxo-bridged diiron proteins that are found only in mycobacterial species that cause respiratory disorders in humans. Because it had been shown to exhibit weak catalase activity and a change in absorbance on exposure to nitric oxide (NO), the reactivity of Mka HLP toward NO was examined under a variety of conditions. Under anaerobic conditions, we found that NO was converted to nitrite (NO2−) via an intermediate, which absorbed light at 520 nm. Under aerobic conditions NO was converted to nitrate (NO3−). In each of these two cases, the maximum amount of nitrite or nitrate formed was at best stoichiometric with the concentration of Mka HLP. When incubated with NO and H2O2, we observed NO peroxidase activity yielding nitrite and water as reaction products. Steady-state kinetic analysis of NO consumption during this reaction yielded a Km for NO of 0.44 μM and a kcat/Km of 2.3 × 105 M−1s−1. This high affinity for NO is consistent with a physiological role for Mka HLP in deterring nitrosative stress. This is the first example of a peroxidase that uses an oxo-bridged diiron center and a rare example of a peroxidase utilizing NO as an electron donor and cosubstrate. This activity provides a mechanism by which the infectious Mycobacterium may combat against the cocktail of NO and superoxide (O2•−) generated by macrophages to defend against bacteria, as well as to produce NO2− to adapt to hypoxic conditions.
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Affiliation(s)
- Zhongxin Ma
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL 32827 United States
| | - Ashley A Holland
- Department of Chemistry, University of Central Florida, 4111 Libra Drive, Room 255, Orlando, Florida 32816, United States
| | - Ilana Szlamkowicz
- Department of Chemistry, University of Central Florida, 4111 Libra Drive, Room 255, Orlando, Florida 32816, United States
| | - Vasileios Anagnostopoulos
- Department of Chemistry, University of Central Florida, 4111 Libra Drive, Room 255, Orlando, Florida 32816, United States
| | - Maria Luiza Caldas Nogueira
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL 32827 United States
| | - Jonathan D Caranto
- Department of Chemistry, University of Central Florida, 4111 Libra Drive, Room 255, Orlando, Florida 32816, United States.
| | - Victor L Davidson
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL 32827 United States.
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35
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Sumii Y, Kamiya K, Nakamura T, Tanaka K, Kaji T, Mukomura J, Kotoku N, Arai M. Study of the Structure–Activity Relationship of an Anti-Dormant Mycobacterial Substance 3-(Phenethylamino)Demethyl(oxy)aaptamine to Create a Probe Molecule for Detecting Its Target Protein. Mar Drugs 2022; 20:md20020098. [PMID: 35200628 PMCID: PMC8879696 DOI: 10.3390/md20020098] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 01/12/2022] [Accepted: 01/19/2022] [Indexed: 02/04/2023] Open
Abstract
The current tuberculosis treatment regimen is long and complex, and its failure leads to relapse and emergence of drug resistance. One of the major reasons underlying the extended chemotherapeutic regimen is the ability of Mycobacterium tuberculosis to attain a dormant state. Therefore, the identification of new lead compounds with chemical structures different from those of conventional anti-tuberculosis drugs is essential. The compound 3-(phenethylamino)demethyl(oxy)aaptamine (PDOA, 1), isolated from marine sponge of Aaptos sp., is known as an anti-dormant mycobacterial substance, and has been reported to be effective against the drug resistant strains of M. tuberculosis. However, its target protein still remains unclear. This study aims to clarify the structure–activity relationship of 1 using 15 synthetic analogues, in order to prepare a probe molecule for detecting the target protein of 1. We succeeded in creating the compound 15 with a photoaffinity group that retained antimicrobial activity, which proved to be a suitable probe molecule for identifying the target protein of 1.
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Affiliation(s)
- Yuji Sumii
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan; (Y.S.); (K.K.); (T.N.); (K.T.); (T.K.)
| | - Kentaro Kamiya
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan; (Y.S.); (K.K.); (T.N.); (K.T.); (T.K.)
| | - Takehiko Nakamura
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan; (Y.S.); (K.K.); (T.N.); (K.T.); (T.K.)
| | - Kenta Tanaka
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan; (Y.S.); (K.K.); (T.N.); (K.T.); (T.K.)
| | - Takumi Kaji
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan; (Y.S.); (K.K.); (T.N.); (K.T.); (T.K.)
| | - Junya Mukomura
- College of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga 525-8577, Japan;
| | - Naoyuki Kotoku
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan; (Y.S.); (K.K.); (T.N.); (K.T.); (T.K.)
- College of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga 525-8577, Japan;
- Correspondence: (N.K.); (M.A.); Tel.: +81-77561-4920 (N.K.); +81-66879-8215 (M.A.); Fax: +81-66879-8215 (M.A.)
| | - Masayoshi Arai
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan; (Y.S.); (K.K.); (T.N.); (K.T.); (T.K.)
- Correspondence: (N.K.); (M.A.); Tel.: +81-77561-4920 (N.K.); +81-66879-8215 (M.A.); Fax: +81-66879-8215 (M.A.)
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Vilchèze C, Yan B, Casey R, Hingley-Wilson S, Ettwiller L, Jacobs WR. Commonalities of Mycobacterium tuberculosis Transcriptomes in Response to Defined Persisting Macrophage Stresses. Front Immunol 2022; 13:909904. [PMID: 35844560 PMCID: PMC9283954 DOI: 10.3389/fimmu.2022.909904] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 06/06/2022] [Indexed: 12/03/2022] Open
Abstract
As the goal of a bacterium is to become bacteria, evolution has imposed continued selections for gene expression. The intracellular pathogen Mycobacterium tuberculosis, the causative agent of tuberculosis, has adopted a fine-tuned response to survive its host's methods to aggressively eradicate invaders. The development of microarrays and later RNA sequencing has led to a better understanding of biological processes controlling the relationship between host and pathogens. In this study, RNA-seq was performed to detail the transcriptomes of M. tuberculosis grown in various conditions related to stresses endured by M. tuberculosis during host infection and to delineate a general stress response incurring during persisting macrophage stresses. M. tuberculosis was subjected to long-term growth, nutrient starvation, hypoxic and acidic environments. The commonalities between these stresses point to M. tuberculosis maneuvering to exploit propionate metabolism for lipid synthesis or to withstand propionate toxicity whilst in the intracellular environment. While nearly all stresses led to a general shutdown of most biological processes, up-regulation of pathways involved in the synthesis of amino acids, cofactors, and lipids were observed only in hypoxic M. tuberculosis. This data reveals genes and gene cohorts that are specifically or exclusively induced during all of these persisting stresses. Such knowledge could be used to design novel drug targets or to define possible M. tuberculosis vulnerabilities for vaccine development. Furthermore, the disruption of specific functions from this gene set will enhance our understanding of the evolutionary forces that have caused the tubercle bacillus to be a highly successful pathogen.
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Affiliation(s)
- Catherine Vilchèze
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Bo Yan
- Research Department, Genome Biology Division, New England Biolabs Inc., Ipswich, MA, United States
| | - Rosalyn Casey
- Department of Microbial Sciences, School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Suzie Hingley-Wilson
- Department of Microbial Sciences, School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Laurence Ettwiller
- Research Department, Genome Biology Division, New England Biolabs Inc., Ipswich, MA, United States
| | - William R. Jacobs
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States
- *Correspondence: William R. Jacobs Jr,
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Sharma A, Sagar K, Chauhan NK, Venkataraman B, Gupta N, Gosain TP, Bhalla N, Singh R, Gupta A. HigB1 Toxin in Mycobacterium tuberculosis Is Upregulated During Stress and Required to Establish Infection in Guinea Pigs. Front Microbiol 2021; 12:748890. [PMID: 34917044 PMCID: PMC8669151 DOI: 10.3389/fmicb.2021.748890] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 10/29/2021] [Indexed: 12/20/2022] Open
Abstract
The extraordinary expansion of Toxin Antitoxin (TA) modules in the genome of Mycobacterium tuberculosis has received significant attention over the last few decades. The cumulative evidence suggests that TA systems are activated in response to stress conditions and are essential for M. tuberculosis pathogenesis. In M. tuberculosis, Rv1955-Rv1956-Rv1957 constitutes the only tripartite TAC (Toxin Antitoxin Chaperone) module. In this locus, Rv1955 (HigB1) encodes for the toxin and Rv1956 (HigA1) encodes for antitoxin. Rv1957 encodes for a SecB-like chaperone that regulates HigBA1 toxin antitoxin system by preventing HigA1 degradation. Here, we have investigated the physiological role of HigB1 toxin in stress adaptation and pathogenesis of Mycobacterium tuberculosis. qPCR studies revealed that higBA1 is upregulated in nutrient limiting conditions and upon exposure to levofloxacin. We also show that the promoter activity of higBA1 locus in M. tuberculosis is (p)ppGpp dependent. We observed that HigB1 locus is non-essential for M. tuberculosis growth under different stress conditions in vitro. However, guinea pigs infected with higB1 deletion strain exhibited significantly reduced bacterial loads and pathological damage in comparison to the animals infected with the parental strain. Transcriptome analysis suggested that deletion of higB1 reduced the expression of genes involved in virulence, detoxification and adaptation. The present study describes the role of higB1 toxin in M. tuberculosis physiology and highlights the importance of higBA1 locus during infection in host tissues.
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Affiliation(s)
- Arun Sharma
- Tuberculosis Research Laboratory, Translational Health Science and Technology Institute, Faridabad, India
| | - Kalpana Sagar
- Department of Biochemistry, University of Delhi South Campus, New Delhi, India.,Centre for Innovation in Infectious Disease Research, Education and Training, New Delhi, India
| | - Neeraj Kumar Chauhan
- Tuberculosis Research Laboratory, Translational Health Science and Technology Institute, Faridabad, India
| | - Balaji Venkataraman
- Department of Biochemistry, University of Delhi South Campus, New Delhi, India
| | - Nidhi Gupta
- Department of Biochemistry, University of Delhi South Campus, New Delhi, India
| | - Tannu Priya Gosain
- Tuberculosis Research Laboratory, Translational Health Science and Technology Institute, Faridabad, India
| | - Nikhil Bhalla
- Department of Biochemistry, University of Delhi South Campus, New Delhi, India
| | - Ramandeep Singh
- Tuberculosis Research Laboratory, Translational Health Science and Technology Institute, Faridabad, India
| | - Amita Gupta
- Department of Biochemistry, University of Delhi South Campus, New Delhi, India.,Centre for Innovation in Infectious Disease Research, Education and Training, New Delhi, India
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Mycobacterial MCE proteins as transporters that control lipid homeostasis of the cell wall. Tuberculosis (Edinb) 2021; 132:102162. [PMID: 34952299 DOI: 10.1016/j.tube.2021.102162] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 11/30/2021] [Accepted: 12/10/2021] [Indexed: 01/05/2023]
Abstract
Mammalian cell entry (mce) genes are not only present in genomes of pathogenic mycobacteria, including Mycobacterium tuberculosis (the causative agent of tuberculosis), but also in saprophytic and opportunistic mycobacterial species. MCE are conserved cell-wall proteins encoded by mce operons, which maintain an identical structure in all mycobacteria: two yrbE genes (A and B) followed by six mce genes (A, B, C, D, E and F). Although these proteins are known to participate in the virulence of pathogenic mycobacteria, the presence of the operons in nonpathogenic mycobacteria and other bacteria indicates that they play another role apart from host cell invasion. In this respect, more recent studies suggest that they are functionally similar to ABC transporters and form part of lipid transporters in Actinobacteria. To date, most reviews on mce operons in the literature discuss their role in virulence. However, according to data from transcriptional studies, mce genes, particularly the mce1 and mce4 operons, modify their expression according to the carbon source and upon hypoxia, starvation, surface stress and oxidative stress; which suggests a role of MCE proteins in the response of Mycobacteria to external stressors. In addition to these data, this review also summarizes the studies demonstrating the role of MCE proteins as lipid transporters as well as the relevance of their transport function in the interaction of pathogenic Mycobacteria with the hosts. Altogether, the evidence to date would indicate that MCE proteins participate in the response to the stress conditions that mycobacteria encounter during infection, by participating in the cell wall remodelling and possibly contributing to lipid homeostasis.
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39
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Joshi H, Kandari D, Bhatnagar R. Insights into the molecular determinants involved in Mycobacterium tuberculosis persistence and their therapeutic implications. Virulence 2021; 12:2721-2749. [PMID: 34637683 PMCID: PMC8565819 DOI: 10.1080/21505594.2021.1990660] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 09/17/2021] [Accepted: 10/05/2021] [Indexed: 01/08/2023] Open
Abstract
The establishment of persistent infections and the reactivation of persistent bacteria to active bacilli are the two hurdles in effective tuberculosis treatment. Mycobacterium tuberculosis, an etiologic tuberculosis agent, adapts to numerous antibiotics and resists the host immune system causing a disease of public health concern. Extensive research has been employed to combat this disease due to its sheer ability to persist in the host system, undetected, waiting for the opportunity to declare itself. Persisters are a bacterial subpopulation that possesses transient tolerance to high doses of antibiotics. There are certain inherent mechanisms that facilitate the persister cell formation in Mycobacterium tuberculosis, some of those had been characterized in the past namely, stringent response, transcriptional regulators, energy production pathways, lipid metabolism, cell wall remodeling enzymes, phosphate metabolism, and proteasome protein degradation. This article reviews the recent advancements made in various in vitro persistence models that assist to unravel the mechanisms involved in the persister cell formation and to hunt for the possible preventive or treatment measures. To tackle the persister population the immunodominant proteins that express specifically at the latent phase of infection can be used for diagnosis to distinguish between the active and latent tuberculosis, as well as to select potential drug or vaccine candidates. In addition, we discuss the genes engaged in the persistence to get more insights into resuscitation and persister cell formation. The in-depth understanding of persistent cells of mycobacteria can certainly unravel novel ways to target the pathogen and tackle its persistence.
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Affiliation(s)
- Hemant Joshi
- Molecular Biology and Genetic Engineering Laboratory, School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
| | - Divya Kandari
- Molecular Biology and Genetic Engineering Laboratory, School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
| | - Rakesh Bhatnagar
- Molecular Biology and Genetic Engineering Laboratory, School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
- Amity University of Rajasthan, Jaipur, Rajasthan, India
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40
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Verma A, Kaur M, Singh LV, Aggarwal D, Verma I, Radotra BD, Sharma S. Reactivation of latent tuberculosis through modulation of resuscitation promoting factors by diabetes. Sci Rep 2021; 11:19700. [PMID: 34611258 PMCID: PMC8492673 DOI: 10.1038/s41598-021-99257-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 08/10/2021] [Indexed: 12/17/2022] Open
Abstract
The evidence of an association between diabetes and latent tuberculosis infection (LTBI) remains limited and inconsistent. Thus, the study aims to delineate the role of diabetes in activation of latent tuberculosis infection. Murine model of latent tuberculosis and diabetes was developed, bacillary load and gene expression of resuscitation promoting factors (rpfA-E) along with histopathological changes in the lungs and spleen were studied. Treatment for LTBI [Rifampicin (RIF) + Isoniazid (INH)] was also given to latently infected mice with or without diabetes for 4 weeks. Diabetes was found to activate latent tuberculosis as the colony forming unit (CFU) counts were observed to be > 104 in lungs and spleen. The gene expression of hspX was downregulated and that of rpfB and rpfD was observed to be upregulated in latently infected mice with diabetes compared to those without diabetes. However, no significant reduction in the CFU counts was observed after 4 weeks of treatment with RIF and INH. Diabetes helps in the progression of LTBI to active disease mainly through altered expression of resuscitation promoting factors rpfB and rpfD, which can serve as important targets to reduce the shared burden of tuberculosis and diabetes.
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Affiliation(s)
- Arpana Verma
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Maninder Kaur
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Lakshya Veer Singh
- TACF, International Centre for Genetic Engineering and Biotechnology, New Delhi, India
| | - Divya Aggarwal
- Department of Histopathology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Indu Verma
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Bishan D Radotra
- Department of Histopathology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Sadhna Sharma
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
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Mukundan S, Singh P, Shah A, Kumar R, O’Neill KC, Carter CL, Russell DG, Subbian S, Parekkadan B. In Vitro Miniaturized Tuberculosis Spheroid Model. Biomedicines 2021; 9:1209. [PMID: 34572395 PMCID: PMC8470281 DOI: 10.3390/biomedicines9091209] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 09/01/2021] [Accepted: 09/06/2021] [Indexed: 12/11/2022] Open
Abstract
Tuberculosis (TB) is a public health concern that impacts 10 million people around the world. Current in vitro models are low throughput and/or lack caseation, which impairs drug effectiveness in humans. Here, we report the generation of THP-1 human monocyte/macrophage spheroids housing mycobacteria (TB spheroids). These TB spheroids have a central core of dead cells co-localized with mycobacteria and are hypoxic. TB spheroids exhibit higher levels of pro-inflammatory factor TNFα and growth factors G-CSF and VEGF when compared to non-infected control. TB spheroids show high levels of lipid deposition, characterized by MALDI mass spectrometry imaging. TB spheroids infected with strains of differential virulence, Mycobacterium tuberculosis (Mtb) HN878 and CDC1551 vary in response to Isoniazid and Rifampicin. Finally, we adapt the spheroid model to form peripheral blood mononuclear cells (PBMCs) and lung fibroblasts (NHLF) 3D co-cultures. These results pave the way for the development of new strategies for disease modeling and therapeutic discovery.
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Affiliation(s)
- Shilpaa Mukundan
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Jersey City, NJ 08854, USA; (S.M.); (A.S.)
| | - Pooja Singh
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Jersey City, NJ 07103, USA; (P.S.); (R.K.); (S.S.)
| | - Aditi Shah
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Jersey City, NJ 08854, USA; (S.M.); (A.S.)
| | - Ranjeet Kumar
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Jersey City, NJ 07103, USA; (P.S.); (R.K.); (S.S.)
| | - Kelly C. O’Neill
- Department Center for Discovery and Innovation, Hackensack Meridian Health, Neptune, NJ 07110, USA; (K.C.O.); (C.L.C.)
| | - Claire L. Carter
- Department Center for Discovery and Innovation, Hackensack Meridian Health, Neptune, NJ 07110, USA; (K.C.O.); (C.L.C.)
| | - David G. Russell
- Department of Microbiology and Immunology, School of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA;
| | - Selvakumar Subbian
- Public Health Research Institute, New Jersey Medical School, Rutgers, The State University of New Jersey, Jersey City, NJ 07103, USA; (P.S.); (R.K.); (S.S.)
| | - Biju Parekkadan
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Jersey City, NJ 08854, USA; (S.M.); (A.S.)
- Department of Medicine, Rutgers Biomedical Health Sciences, Rutgers, The State University of New Jersey, Jersey City, NJ 08854, USA
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Early phase of effective treatment induces distinct transcriptional changes in Mycobacterium tuberculosis expelled by pulmonary tuberculosis patients. Sci Rep 2021; 11:17812. [PMID: 34497280 PMCID: PMC8426492 DOI: 10.1038/s41598-021-96902-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/18/2021] [Indexed: 12/25/2022] Open
Abstract
Effective treatment reduces a tuberculosis patient's ability to infect others even before they test negative in sputum or culture. Currently, the basis of reduced infectiousness of the Mycobacterium tuberculosis (Mtb) with effective treatment is unclear. We evaluated changes in aerosolized bacteria expelled by patients through a transcriptomic approach before and after treatment initiation (up to 14 days) by RNA sequencing. A distinct change in the overall transcriptional profile was seen post-treatment initiation compared to pretreatment, only when patients received effective treatment. This also led to the downregulation of genes associated with cellular activities, cell wall assembly, virulence factors indicating loss of pathogenicity, and a diminished ability to infect and survive in new host cells. Based on this, we identified genes whose expression levels changed with effective treatment. The observations of the study open up avenues for further evaluating the changes in bacterial gene expression during the early phase of treatment as biomarkers for monitoring response to tuberculosis treatment regimens and provide means of identifying better correlates of Mtb transmission.
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In-vivo expressed Mycobacterium tuberculosis antigens recognised in three mouse strains after infection and BCG vaccination. NPJ Vaccines 2021; 6:81. [PMID: 34083546 PMCID: PMC8175414 DOI: 10.1038/s41541-021-00343-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 04/23/2021] [Indexed: 01/15/2023] Open
Abstract
Novel tuberculosis (TB)-vaccines preferably should (i) boost host immune responses induced by previous BCG vaccination and (ii) be directed against Mycobacterium tuberculosis (Mtb) proteins expressed throughout the Mtb infection-cycle. Human Mtb antigen-discovery screens identified antigens encoded by Mtb-genes highly expressed during in vivo murine infection (IVE-TB antigens). To translate these findings towards animal models, we determined which IVE-TB-antigens are recognised by T-cells following Mtb challenge or BCG vaccination in three different mouse strains. Eleven Mtb-antigens were recognised across TB-resistant and susceptible mice. Confirming previous human data, several Mtb-antigens induced cytokines other than IFN-γ. Pulmonary cells from susceptible C3HeB/FeJ mice produced less TNF-α, agreeing with the TB-susceptibility phenotype. In addition, responses to several antigens were induced by BCG in C3HeB/FeJ mice, offering potential for boosting. Thus, recognition of promising Mtb-antigens identified in humans validates across multiple mouse TB-infection models with widely differing TB-susceptibilities. This offers translational tools to evaluate IVE-TB-antigens as diagnostic and vaccine antigens.
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Collateral Sensitivity to β-Lactam Drugs in Drug-Resistant Tuberculosis Is Driven by the Transcriptional Wiring of BlaI Operon Genes. mSphere 2021; 6:e0024521. [PMID: 34047652 PMCID: PMC8265638 DOI: 10.1128/msphere.00245-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The evolution of resistance to one antimicrobial can result in enhanced sensitivity to another, known as "collateral sensitivity." This underexplored phenomenon opens new therapeutic possibilities for patients infected with pathogens unresponsive to classical treatments. Intrinsic resistance to β-lactams in Mycobacterium tuberculosis (the causative agent of tuberculosis) has traditionally curtailed the use of these low-cost and easy-to-administer drugs for tuberculosis treatment. Recently, β-lactam sensitivity has been reported in strains resistant to classical tuberculosis therapy, resurging the interest in β-lactams for tuberculosis. However, a lack of understanding of the molecular underpinnings of this sensitivity has delayed exploration in the clinic. We performed gene expression and network analyses and in silico knockout simulations of genes associated with β-lactam sensitivity and genes associated with resistance to classical tuberculosis drugs to investigate regulatory interactions and identify key gene mediators. We found activation of the key inhibitor of β-lactam resistance, blaI, following classical drug treatment as well as transcriptional links between genes associated with β-lactam sensitivity and those associated with resistance to classical treatment, suggesting that regulatory links might explain collateral sensitivity to β-lactams. Our results support M. tuberculosis β-lactam sensitivity as a collateral consequence of the evolution of resistance to classical tuberculosis drugs, mediated through changes to transcriptional regulation. These findings support continued exploration of β-lactams for the treatment of patients infected with tuberculosis strains resistant to classical therapies. IMPORTANCE Tuberculosis remains a significant cause of global mortality, with strains resistant to classical drug treatment considered a major health concern by the World Health Organization. Challenging treatment regimens and difficulty accessing drugs in low-income communities have led to a high prevalence of strains resistant to multiple drugs, making the development of alternative therapies a priority. Although Mycobacterium tuberculosis is naturally resistant to β-lactam drugs, previous studies have shown sensitivity in strains resistant to classical drug treatment, but we currently lack understanding of the molecular underpinnings behind this phenomenon. We found that genes involved in β-lactam susceptibility are activated after classical drug treatment resulting from tight regulatory links with genes involved in drug resistance. Our study supports the hypothesis that β-lactam susceptibility observed in drug-resistant strains results from the underlying regulatory network of M. tuberculosis, supporting further exploration of the use of β-lactams for tuberculosis treatment.
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Peterson EJR, Abidi AA, Arrieta-Ortiz ML, Aguilar B, Yurkovich JT, Kaur A, Pan M, Srinivas V, Shmulevich I, Baliga NS. Intricate Genetic Programs Controlling Dormancy in Mycobacterium tuberculosis. Cell Rep 2021; 31:107577. [PMID: 32348771 PMCID: PMC7605849 DOI: 10.1016/j.celrep.2020.107577] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 12/18/2019] [Accepted: 04/06/2020] [Indexed: 11/24/2022] Open
Abstract
Mycobacterium tuberculosis (MTB) displays the remarkable ability to transition in and out of dormancy, a hallmark of the pathogen’s capacity to evade the immune system and exploit susceptible individuals. Uncovering the gene regulatory programs that underlie the phenotypic shifts in MTB during disease latency and reactivation has posed a challenge. We develop an experimental system to precisely control dissolved oxygen levels in MTB cultures in order to capture the transcriptional events that unfold as MTB transitions into and out of hypoxia-induced dormancy. Using a comprehensive genome-wide transcription factor binding map and insights from network topology analysis, we identify regulatory circuits that deterministically drive sequential transitions across six transcriptionally and functionally distinct states encompassing more than three-fifths of the MTB genome. The architecture of the genetic programs explains the transcriptional dynamics underlying synchronous entry of cells into a dormant state that is primed to infect the host upon encountering favorable conditions. Mycobacterium tuberculosis (MTB) persists within the host by counteracting disparate stressors including hypoxia. Peterson et al. report a transcriptional program that coordinates sequential state transitions to drive MTB in and out of hypoxia-induced dormancy. Among varied properties, this program encodes advanced preparedness to infect the host in favorable conditions.
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Affiliation(s)
| | - Abrar A Abidi
- Institute for Systems Biology, Seattle, WA 98109, USA
| | | | - Boris Aguilar
- Institute for Systems Biology, Seattle, WA 98109, USA
| | | | - Amardeep Kaur
- Institute for Systems Biology, Seattle, WA 98109, USA
| | - Min Pan
- Institute for Systems Biology, Seattle, WA 98109, USA
| | | | | | - Nitin S Baliga
- Institute for Systems Biology, Seattle, WA 98109, USA; Molecular and Cellular Biology Program, Departments of Microbiology and Biology, University of Washington, Seattle, WA; Lawrence Berkeley National Laboratories, Berkeley, CA.
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Abstract
Carbon monoxide has an infamous reputation as a toxic gas, and it has been suggested that it has potential as an antibacterial agent. Despite this, how bacteria resist its toxic effects is not well understood. Carbon monoxide (CO) gas is infamous for its acute toxicity. This toxicity predominantly stems from its tendency to form carbonyl complexes with transition metals, thus inhibiting the heme-prosthetic groups of proteins, including respiratory terminal oxidases. While CO has been proposed as an antibacterial agent, the evidence supporting its toxicity toward bacteria is equivocal, and its cellular targets remain poorly defined. In this work, we investigate the physiological response of mycobacteria to CO. We show that Mycobacterium smegmatis is highly resistant to the toxic effects of CO, exhibiting only minor inhibition of growth when cultured in its presence. We profiled the proteome of M. smegmatis during growth in CO, identifying strong induction of cytochrome bd oxidase and members of the dos regulon, but relatively few other changes. We show that the activity of cytochrome bd oxidase is resistant to CO, whereas cytochrome bcc-aa3 oxidase is strongly inhibited by this gas. Consistent with these findings, growth analysis shows that M. smegmatis lacking cytochrome bd oxidase displays a significant growth defect in the presence of CO, while induction of the dos regulon appears to be unimportant for adaptation to CO. Altogether, our findings indicate that M. smegmatis has considerable resistance to CO and benefits from respiratory flexibility to withstand its inhibitory effects. IMPORTANCE Carbon monoxide has an infamous reputation as a toxic gas, and it has been suggested that it has potential as an antibacterial agent. Despite this, how bacteria resist its toxic effects is not well understood. In this study, we investigated how CO influences growth, proteome, and aerobic respiration of wild-type and mutant strains of Mycobacterium smegmatis. We show that this bacterium produces the CO-resistant cytochrome bd oxidase to tolerate poisoning of its CO-sensitive complex IV homolog. Further, we show that aside from this remodeling of its respiratory chain, M. smegmatis makes few other functional changes to its proteome, suggesting it has a high level of inherent resistance to CO.
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Huang S, Zhou W, Tang W, Zhang Y, Hu Y, Chen S. Genome-scale analyses of transcriptional start sites in Mycobacterium marinum under normoxic and hypoxic conditions. BMC Genomics 2021; 22:235. [PMID: 33823801 PMCID: PMC8022548 DOI: 10.1186/s12864-021-07572-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 03/26/2021] [Indexed: 11/23/2022] Open
Abstract
Background Hypoxic stress plays a critical role in the persistence of Mycobacterium tuberculosis (Mtb) infection, but the mechanisms underlying this adaptive response remain ill defined. Material and methods In this study, using M. marinum as a surrogate, we analyzed hypoxic responses at the transcriptional level by Cappable-seq and regular RNA-seq analyses. Results A total of 6808 transcriptional start sites (TSSs) were identified under normoxic and hypoxic conditions. Among these TSSs, 1112 were upregulated and 1265 were downregulated in response to hypoxic stress. Using SigE-recognized consensus sequence, we identified 59 SigE-dependent promoters and all were upregulated under hypoxic stress, suggesting an important role for SigE in this process. We also compared the performance of Cappable-seq and regular RNA-seq using the same RNA samples collected from normoxic and hypoxic conditions, and confirmed that Cappable-seq is a valuable approach for global transcriptional regulation analyses. Conclusions Our results provide insights and information for further characterization of responses to hypoxia in mycobacteria, and prove that Cappable-seq is a valuable approach for global transcriptional studies in mycobacteria. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-07572-8.
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Affiliation(s)
- Shaojia Huang
- CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wei Zhou
- CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wei Tang
- CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Yong Zhang
- CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Yangbo Hu
- CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China.
| | - Shiyun Chen
- CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, 430071, China.
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Grosse-Siestrup BT, Gupta T, Helms S, Tucker SL, Voskuil MI, Quinn FD, Karls RK. A Role for Mycobacterium tuberculosis Sigma Factor C in Copper Nutritional Immunity. Int J Mol Sci 2021; 22:2118. [PMID: 33672733 PMCID: PMC7924339 DOI: 10.3390/ijms22042118] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Revised: 02/09/2021] [Accepted: 02/17/2021] [Indexed: 11/22/2022] Open
Abstract
Sigma factor C (SigC) contributes to Mycobacterium tuberculosis virulence in various animal models, but the stress response coordinated by this transcription factor was undefined. The results presented here indicate that SigC prevents copper starvation. Whole genome expression studies demonstrate short-term (4-h) induction of sigC, controlled from a tetracycline-inducible promoter, upregulates ctpB and genes in the nonribosomal peptide synthase (nrp) operon. These genes are expressed at higher levels after 48-h sigC induction, but also elevated are genes encoding copper-responsive regulator RicR and RicR-regulated copper toxicity response operon genes rv0846-rv0850, suggesting prolonged sigC induction results in excessive copper uptake. No growth and global transcriptional differences are observed between a sigC null mutant relative to its parent strain in 7H9 medium. In a copper-deficient medium, however, growth of the sigC deletion strain lags the parent, and 40 genes (including those in the nrp operon) are differentially expressed. Copper supplementation reverses the growth defect and silences most transcriptional differences. Together, these data support SigC as a transcriptional regulator of copper acquisition when the metal is scarce. Attenuation of sigC mutants in severe combined immunodeficient mice is consistent with an inability to overcome innate host defenses that sequester copper ions to deprive invading microbes of this essential micronutrient.
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Affiliation(s)
- Benjamin T. Grosse-Siestrup
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA; (B.T.G.-S.); (T.G.); (S.H.); (S.L.T.); (F.D.Q.)
| | - Tuhina Gupta
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA; (B.T.G.-S.); (T.G.); (S.H.); (S.L.T.); (F.D.Q.)
| | - Shelly Helms
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA; (B.T.G.-S.); (T.G.); (S.H.); (S.L.T.); (F.D.Q.)
| | - Samantha L. Tucker
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA; (B.T.G.-S.); (T.G.); (S.H.); (S.L.T.); (F.D.Q.)
| | - Martin I. Voskuil
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA;
| | - Frederick D. Quinn
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA; (B.T.G.-S.); (T.G.); (S.H.); (S.L.T.); (F.D.Q.)
| | - Russell K. Karls
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA; (B.T.G.-S.); (T.G.); (S.H.); (S.L.T.); (F.D.Q.)
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Chang DPS, Guan XL. Metabolic Versatility of Mycobacterium tuberculosis during Infection and Dormancy. Metabolites 2021; 11:88. [PMID: 33540752 PMCID: PMC7913082 DOI: 10.3390/metabo11020088] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 01/16/2021] [Accepted: 01/29/2021] [Indexed: 12/18/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), is a highly successful intracellular pathogen with the ability to withstand harsh conditions and reside long-term within its host. In the dormant and persistent states, the bacterium tunes its metabolism and is able to resist the actions of antibiotics. One of the main strategies Mtb adopts is through its metabolic versatility-it is able to cometabolize a variety of essential nutrients and direct these nutrients simultaneously to multiple metabolic pathways to facilitate the infection of the host. Mtb further undergo extensive remodeling of its metabolic pathways in response to stress and dormancy. In recent years, advancement in systems biology and its applications have contributed substantially to a more coherent view on the intricate metabolic networks of Mtb. With a more refined appreciation of the roles of metabolism in mycobacterial infection and drug resistance, and the success of drugs targeting metabolism, there is growing interest in further development of anti-TB therapies that target metabolism, including lipid metabolism and oxidative phosphorylation. Here, we will review current knowledge revolving around the versatility of Mtb in remodeling its metabolism during infection and dormancy, with a focus on central carbon metabolism and lipid metabolism.
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Affiliation(s)
| | - Xue Li Guan
- Lee Kong Chian School of Medicine, Nanyang Technological University, 59 Nanyang Drive, Singapore 636921, Singapore;
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50
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Banerjee U, Sankar S, Singh A, Chandra N. A Multi-Pronged Computational Pipeline for Prioritizing Drug Target Strategies for Latent Tuberculosis. Front Chem 2020; 8:593497. [PMID: 33381491 PMCID: PMC7767875 DOI: 10.3389/fchem.2020.593497] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 11/24/2020] [Indexed: 12/02/2022] Open
Abstract
Tuberculosis is one of the deadliest infectious diseases worldwide and the prevalence of latent tuberculosis acts as a huge roadblock in the global effort to eradicate tuberculosis. Most of the currently available anti-tubercular drugs act against the actively replicating form of Mycobacterium tuberculosis (Mtb), and are not effective against the non-replicating dormant form present in latent tuberculosis. With about 30% of the global population harboring latent tuberculosis and the requirement for prolonged treatment duration with the available drugs in such cases, the rate of adherence and successful completion of therapy is low. This necessitates the discovery of new drugs effective against latent tuberculosis. In this work, we have employed a combination of bioinformatics and chemoinformatics approaches to identify potential targets and lead candidates against latent tuberculosis. Our pipeline adopts transcriptome-integrated metabolic flux analysis combined with an analysis of a transcriptome-integrated protein-protein interaction network to identify perturbations in dormant Mtb which leads to a shortlist of 6 potential drug targets. We perform a further selection of the candidate targets and identify potential leads for 3 targets using a range of bioinformatics methods including structural modeling, binding site association and ligand fingerprint similarities. Put together, we identify potential new strategies for targeting latent tuberculosis, new candidate drug targets as well as important lead clues for drug design.
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Affiliation(s)
- Ushashi Banerjee
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Santhosh Sankar
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Amit Singh
- Center for Infectious Disease Research, Indian Institute of Science, Bangalore, India
| | - Nagasuma Chandra
- Department of Biochemistry, Indian Institute of Science, Bangalore, India.,Center for Biosystems Science and Engineering, Indian Institute of Science, Bangalore, India
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