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Sangal V, Marrs ECL, Nelson A, Perry JD. Phylogenomic analyses of multidrug resistant Corynebacterium striatum strains isolated from patients in a tertiary care hospital in the UK. Eur J Clin Microbiol Infect Dis 2024:10.1007/s10096-024-04857-0. [PMID: 38801486 DOI: 10.1007/s10096-024-04857-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Accepted: 05/17/2024] [Indexed: 05/29/2024]
Abstract
Corynebacterium striatum is an emerging nosocomial pathogen. This is the first report showing the presence of three distinct multidrug resistant lineages of C. striatum among patients in a UK hospital. The presence of ErmX, Tet(W), Bla and AmpC proteins, and mutations in gyrA gene are associated with the resistance to clindamycin, doxycycline, penicillin and moxifloxacin, respectively. These strains are equipped with several corynebacterial virulence genes including two SpaDEF-type and a novel pilus gene cluster, which needs further molecular characterisation. This study highlights a need of developing an active surveillance strategy for routine monitoring and preventing potential cross-transmission among susceptible patients.
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Affiliation(s)
- Vartul Sangal
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK.
| | - Emma C L Marrs
- Microbiology Research Department, Freeman Hospital, Newcastle upon Tyne, UK
| | - Andrew Nelson
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - John D Perry
- Microbiology Research Department, Freeman Hospital, Newcastle upon Tyne, UK
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2
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Bagchi S, Sharma AK, Ghosh A, Saha S, Basu J, Kundu M. RegX3-dependent transcriptional activation of kdpDE and repression of rv0500A are linked to potassium homeostasis in Mycobacterium tuberculosis. FEBS J 2024. [PMID: 38414198 DOI: 10.1111/febs.17100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 01/18/2024] [Accepted: 02/12/2024] [Indexed: 02/29/2024]
Abstract
Ionic homeostasis is essential for the survival and replication of Mycobacterium tuberculosis within its host. Low potassium ion concentrations trigger a transition of M. tuberculosis into dormancy. Our current knowledge of the transcriptional regulation mechanisms governing genes involved in potassium homeostasis remains limited. Potassium transport is regulated by the constitutive Trk system and the inducible Kdp system in M. tuberculosis. The two-component system KdpDE (also known as KdpD/KdpE) activates expression of the kdpFABC operon, encoding the four protein subunits of the Kdp potassium uptake system (KdpFABC). We show that, under potassium deficiency, expression of the two-component system senX3/regX3 is upregulated, and bacterial survival is compromised in a regX3-inactivated mutant, ΔregX3. Electrophoretic mobility shift assays (EMSAs), promoter reporter assays and chromatin immunoprecipitation (ChIP) show that RegX3 binds to the kdpDE promoter and activates it under potassium deficiency, whereas RegX3 (K204A), a DNA binding-deficient mutant, fails to bind to the promoter. Mutation of the RegX3 binding motifs on the kdpDE promoter abrogates RegX3 binding. In addition, EMSAs and ChIP assays show that RegX3 represses Rv0500A, a repressor of kdpFABC, by binding to consensus RegX3 binding motifs on the rv0500A promoter. Our findings provide important insight into two converging pathways regulated by RegX3; one in which it activates an activator of kdpFABC, and the other in which it represses a repressor of kdpFABC, during potassium insufficiency. This culminates in increased expression of the potassium uptake system encoded by kdpFABC, enabling bacterial survival. These results further expand the growing transcriptional network in which RegX3 serves as a central node to enable bacterial survival under stress.
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Affiliation(s)
- Shreya Bagchi
- Department of Chemical Sciences, Bose Institute, Kolkata, India
| | | | - Abhirupa Ghosh
- Department of Biological Sciences, Bose Institute, Kolkata, India
| | - Sudipto Saha
- Department of Biological Sciences, Bose Institute, Kolkata, India
| | - Joyoti Basu
- Department of Chemical Sciences, Bose Institute, Kolkata, India
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3
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Xing J, Gumerov VM, Zhulin IB. Origin and functional diversification of PAS domain, a ubiquitous intracellular sensor. SCIENCE ADVANCES 2023; 9:eadi4517. [PMID: 37647406 PMCID: PMC10468136 DOI: 10.1126/sciadv.adi4517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 07/28/2023] [Indexed: 09/01/2023]
Abstract
Signal perception is a key function in regulating biological activities and adapting to changing environments. Per-Arnt-Sim (PAS) domains are ubiquitous sensors found in diverse receptors in bacteria, archaea, and eukaryotes, but their origins, distribution across the tree of life, and extent of their functional diversity are not fully characterized. Here, we show that using sequence conservation and structural information, it is possible to propose specific and potential functions for a large portion of nearly 3 million PAS domains. Our analysis suggests that PAS domains originated in bacteria and were horizontally transferred to archaea and eukaryotes. We reveal that gas sensing via a heme cofactor evolved independently in several lineages, whereas redox and light sensing via flavin adenine dinucleotide and flavin mononucleotide cofactors have the same origin. The close relatedness of human PAS domains to those in bacteria provides an opportunity for drug design by exploring potential natural ligands and cofactors for bacterial homologs.
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Affiliation(s)
- Jiawei Xing
- Department of Microbiology, The Ohio State University, Columbus, OH, USA
- Translational Data Analytics Institute, The Ohio State University, Columbus, OH USA
| | - Vadim M. Gumerov
- Department of Microbiology, The Ohio State University, Columbus, OH, USA
- Translational Data Analytics Institute, The Ohio State University, Columbus, OH USA
| | - Igor B. Zhulin
- Department of Microbiology, The Ohio State University, Columbus, OH, USA
- Translational Data Analytics Institute, The Ohio State University, Columbus, OH USA
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4
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Inflammation-mediated tissue damage in pulmonary tuberculosis and host-directed therapeutic strategies. Semin Immunol 2023; 65:101672. [PMID: 36469987 DOI: 10.1016/j.smim.2022.101672] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Revised: 11/04/2022] [Accepted: 11/08/2022] [Indexed: 12/04/2022]
Abstract
Treatment of tuberculosis (TB) involves the administration of anti-mycobacterial drugs for several months. The emergence of drug-resistant strains of Mycobacterium tuberculosis (Mtb, the causative agent) together with increased disease severity in people with co-morbidities such as diabetes mellitus and HIV have hampered efforts to reduce case fatality. In severe disease, TB pathology is largely attributable to over-exuberant host immune responses targeted at controlling bacterial replication. Non-resolving inflammation driven by host pro-inflammatory mediators in response to high bacterial load leads to pulmonary pathology including cavitation and fibrosis. The need to improve clinical outcomes and reduce treatment times has led to a two-pronged approach involving the development of novel antimicrobials as well as host-directed therapies (HDT) that favourably modulate immune responses to Mtb. HDT strategies incorporate aspects of immune modulation aimed at downregulating non-productive inflammatory responses and augmenting antimicrobial effector mechanisms to minimise pulmonary pathology and accelerate symptom resolution. HDT in combination with existing antimycobacterial agents offers a potentially promising strategy to improve the long-term outcome for TB patients. In this review, we describe components of the host immune response that contribute to inflammation and tissue damage in pulmonary TB, including cytokines, matrix metalloproteinases, lipid mediators, and neutrophil extracellular traps. We then proceed to review HDT directed at these pathways.
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5
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Jesus HNR, Ramos JN, Rocha DJPG, Alves DA, Silva CS, Cruz JVO, Vieira VV, Souza C, Santos LS, Navas J, Ramos RTJ, Azevedo V, Aguiar ERGR, Mattos-Guaraldi AL, Pacheco LGC. The pan-genome of the emerging multidrug-resistant pathogen Corynebacterium striatum. Funct Integr Genomics 2022; 23:5. [PMID: 36534203 DOI: 10.1007/s10142-022-00932-x] [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: 05/17/2022] [Revised: 10/06/2022] [Accepted: 11/24/2022] [Indexed: 12/23/2022]
Abstract
Corynebacterium striatum, a common constituent of the human skin microbiome, is now considered an emerging multidrug-resistant pathogen of immunocompromised and chronically ill patients. However, little is known about the molecular mechanisms in the transition from colonization to the multidrug-resistant (MDR) invasive phenotype in clinical isolates. This study performed a comprehensive pan-genomic analysis of C. striatum, including isolates from "normal skin microbiome" and from MDR infections, to gain insights into genetic factors contributing to pathogenicity and multidrug resistance in this species. For this, three novel genome sequences were obtained from clinical isolates of C. striatum of patients from Brazil, and other 24 complete or draft C. striatum genomes were retrieved from GenBank, including the ATCC6940 isolate from the Human Microbiome Project. Analysis of C. striatum strains demonstrated the presence of an open pan-genome (α = 0.852803) containing 3816 gene families, including 15 antimicrobial resistance (AMR) genes and 32 putative virulence factors. The core and accessory genomes included 1297 and 1307 genes, respectively. The identified AMR genes are primarily associated with resistance to aminoglycosides and tetracyclines. Of these, 66.6% are present in genomic islands, and four AMR genes, including aac(6')-ib7, are located in a class 1-integron. In conclusion, our data indicated that C. striatum possesses genomic characteristics favorable to the invasive phenotype, with high genomic plasticity, a robust genetic arsenal for iron acquisition, and important virulence determinants and AMR genes present in mobile genetic elements.
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Affiliation(s)
- Hendor N R Jesus
- Multicenter Post-Graduate Program in Biochemistry and Molecular Biology (PMBqBM), Institute of Health Sciences, Federal University of Bahia, Salvador, BA, Brazil
| | - Juliana N Ramos
- Laboratory of Diphtheria and Corinebacteria of Clinical Relevance, School of Medical Sciences, Rio de Janeiro State University - LDCIC/FCM/UERJ, Rio de Janeiro, RJ, Brazil
| | - Danilo J P G Rocha
- Institute of Health Sciences, Federal University of Bahia, Salvador, BA, Brazil
| | - Daniele A Alves
- Institute of Health Sciences, Federal University of Bahia, Salvador, BA, Brazil.,Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Carolina S Silva
- Institute of Health Sciences, Federal University of Bahia, Salvador, BA, Brazil
| | - João V O Cruz
- Institute of Health Sciences, Federal University of Bahia, Salvador, BA, Brazil
| | - Verônica V Vieira
- Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório Interdisciplinar de Pesquisas Médicas, Rio de Janeiro, RJ, Brazil
| | - Cassius Souza
- Laboratory of Diphtheria and Corinebacteria of Clinical Relevance, School of Medical Sciences, Rio de Janeiro State University - LDCIC/FCM/UERJ, Rio de Janeiro, RJ, Brazil
| | - Louisy S Santos
- Laboratory of Diphtheria and Corinebacteria of Clinical Relevance, School of Medical Sciences, Rio de Janeiro State University - LDCIC/FCM/UERJ, Rio de Janeiro, RJ, Brazil
| | - Jesus Navas
- Cantabria University, Instituto de Investigación Valdecilla (IDIVAL), Santander, Spain
| | - Rommel T J Ramos
- Institute of Biological Sciences, Federal University of Para, Belem, PA, Brazil.,Biological Engineering Laboratory, Science and Technology Park Guama, Belem, PA, Brazil
| | - Vasco Azevedo
- Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Eric R G R Aguiar
- Department of Biological Sciences, State University of Santa Cruz, Ilhéus, BA, Brazil
| | - Ana L Mattos-Guaraldi
- Laboratory of Diphtheria and Corinebacteria of Clinical Relevance, School of Medical Sciences, Rio de Janeiro State University - LDCIC/FCM/UERJ, Rio de Janeiro, RJ, Brazil
| | - Luis G C Pacheco
- Multicenter Post-Graduate Program in Biochemistry and Molecular Biology (PMBqBM), Institute of Health Sciences, Federal University of Bahia, Salvador, BA, Brazil. .,Institute of Health Sciences, Federal University of Bahia, Salvador, BA, Brazil.
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6
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Mycobacterium tuberculosis whiB3 and Lipid Metabolism Genes Are Regulated by Host Induced Oxidative Stress. Microorganisms 2022; 10:microorganisms10091821. [PMID: 36144423 PMCID: PMC9506551 DOI: 10.3390/microorganisms10091821] [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: 08/15/2022] [Revised: 09/05/2022] [Accepted: 09/07/2022] [Indexed: 11/23/2022] Open
Abstract
The physiological state of the human macrophage may impact the metabolism and the persistence of Mycobacterium tuberculosis. This pathogen senses and counters the levels of O2, CO, reactive oxygen species (ROS), and pH in macrophages. M. tuberculosis responds to oxidative stress through WhiB3. The goal was to determine the effect of NADPH oxidase (NOX) modulation and oxidative agents on the expression of whiB3 and genes involved in lipid metabolism (lip-Y, Icl-1, and tgs-1) in intracellular mycobacteria. Human macrophages were first treated with NOX modulators such as DPI (ROS inhibitor) and PMA (ROS activator), or with oxidative agents (H2O2 and generator system O2•-), and then infected with mycobacteria. We determined ROS production, cell viability, and expression of whiB3, as well as genes involved in lipid metabolism. PMA, H2O2, and O2•- increased ROS production in human macrophages, generating oxidative stress in bacteria and augmented the gene expression of whiB3, lip-Y, Icl-1, and tgs-1. Our results suggest that ROS production in macrophages induces oxidative stress in intracellular bacteria inducing whiB3 expression. This factor may activate the synthesis of reserve lipids produced to survive in the latency state, which allows its persistence for long periods within the host.
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7
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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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8
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Płocińska R, Wasik K, Płociński P, Lechowicz E, Antczak M, Błaszczyk E, Dziadek B, Słomka M, Rumijowska-Galewicz A, Dziadek J. The Orphan Response Regulator Rv3143 Modulates the Activity of the NADH Dehydrogenase Complex (Nuo) in Mycobacterium tuberculosis via Protein–Protein Interactions. Front Cell Infect Microbiol 2022; 12:909507. [PMID: 35837472 PMCID: PMC9274095 DOI: 10.3389/fcimb.2022.909507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 05/23/2022] [Indexed: 11/13/2022] Open
Abstract
Two-component signal transduction systems enable mycobacterial cells to quickly adapt and adequately respond to adverse environmental conditions encountered at various stages of host infection. We attempted to determine the role of the Rv3143 “orphan” response regulator in the physiology of Mycobacterium tuberculosis and its orthologue Msmeg_2064 in Mycobacterium smegmatis. We identified the Rv3143 protein as an interaction partner for NuoD, a member of the type I NADH dehydrogenase complex involved in oxidative phosphorylation. The mutants Δrv3143 and Δmsmeg_2064 were engineered in M. tuberculosis and M. smegmatis cells, respectively. The Δmsmeg_2064 strain exhibited a significant reduction in growth and viability in the presence of reactive nitrogen species. The Rv3143-deficient strain was sensitive to valinomycin, which is known to reduce the electrochemical potential of the cell and overexpressed genes required for nitrate respiration. An increased level of reduction of the 2,3,5-triphenyltetrazolium chloride (TTC) electron acceptor in Δrv3143 and Δmsmeg_2064 cells was also evident. The silencing of ndh expression using CRISPRi/dCas9 affected cell survival under limited oxygen conditions. Oxygen consumption during entry to hypoxia was most severely affected in the double-mutant Δmsmeg_2064 ndhCRISPRi/dCas9. We propose that the regulatory protein Rv3143 is a component of the Nuo complex and modulates its activity.
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Affiliation(s)
- Renata Płocińska
- Department of Genetics and Physiology of Mycobacteria, Institute of Medical Biology of the Polish Academy of Sciences, Łódź, Poland
| | - Karolina Wasik
- Department of Genetics and Physiology of Mycobacteria, Institute of Medical Biology of the Polish Academy of Sciences, Łódź, Poland
| | - Przemysław Płociński
- Department of Genetics and Physiology of Mycobacteria, Institute of Medical Biology of the Polish Academy of Sciences, Łódź, Poland
- Department of Immunology and Infectious Biology, Faculty of Biology and Environmental Protection, University of Łódz, Łódź, Poland
| | - Ewelina Lechowicz
- Department of Genetics and Physiology of Mycobacteria, Institute of Medical Biology of the Polish Academy of Sciences, Łódź, Poland
| | - Magdalena Antczak
- Department of Genetics and Physiology of Mycobacteria, Institute of Medical Biology of the Polish Academy of Sciences, Łódź, Poland
| | - Ewelina Błaszczyk
- Department of Genetics and Physiology of Mycobacteria, Institute of Medical Biology of the Polish Academy of Sciences, Łódź, Poland
| | - Bożena Dziadek
- Department of Molecular Microbiology, Faculty of Biology and Environmental Protection, University of Łódz, Łódź, Poland
| | - Marcin Słomka
- Biobank Lab, Department of Molecular Biophysics, Faculty of Biology and Environmental Protection, University of Łódź, Łódź, Poland
| | - Anna Rumijowska-Galewicz
- Department of Genetics and Physiology of Mycobacteria, Institute of Medical Biology of the Polish Academy of Sciences, Łódź, Poland
| | - Jarosław Dziadek
- Department of Genetics and Physiology of Mycobacteria, Institute of Medical Biology of the Polish Academy of Sciences, Łódź, Poland
- *Correspondence: Jarosław Dziadek,
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9
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Stupar M, Furness J, De Voss CJ, Tan L, West NP. Two-component sensor histidine kinases of Mycobacterium tuberculosis: beacons for niche navigation. Mol Microbiol 2022; 117:973-985. [PMID: 35338720 PMCID: PMC9321153 DOI: 10.1111/mmi.14899] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 03/12/2022] [Accepted: 03/22/2022] [Indexed: 11/27/2022]
Abstract
Intracellular bacterial pathogens such as Mycobacterium tuberculosis are remarkably adept at surviving within a host, employing a variety of mechanisms to counteract host defenses and establish a protected niche. Constant surveying of the environment is key for pathogenic mycobacteria to discern their immediate location and coordinate the expression of genes necessary for adaptation. Two‐component systems efficiently perform this role, typically comprised of a transmembrane sensor kinase and a cytoplasmic response regulator. In this review, we describe the role of two‐component systems in bacterial pathogenesis, focusing predominantly on the role of sensor kinases of M. tuberculosis. We highlight important features of sensor kinases in mycobacterial infection, discuss ways in which these signaling proteins sense and respond to environments, and how this is attuned to their intracellular lifestyle. Finally, we discuss recent studies which have identified and characterized inhibitors of two‐component sensor kinases toward establishing a new strategy in anti‐mycobacterial therapy.
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Affiliation(s)
- Miljan Stupar
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, University of Queensland, Brisbane, 4072, Australia
| | - Juanelle Furness
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, University of Queensland, Brisbane, 4072, Australia
| | - Christopher J De Voss
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, University of Queensland, Brisbane, 4072, Australia
| | - Lendl Tan
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, University of Queensland, Brisbane, 4072, Australia
| | - Nicholas P West
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, University of Queensland, Brisbane, 4072, Australia
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10
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Birhanu AG, Gómez-Muñoz M, Kalayou S, Riaz T, Lutter T, Yimer SA, Abebe M, Tønjum T. Proteome Profiling of Mycobacterium tuberculosis Cells Exposed to Nitrosative Stress. ACS OMEGA 2022; 7:3470-3482. [PMID: 35128256 PMCID: PMC8811941 DOI: 10.1021/acsomega.1c05923] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 12/08/2021] [Indexed: 06/14/2023]
Abstract
Reactive nitrogen species (RNS) are secreted by human cells in response to infection by Mycobacterium tuberculosis (Mtb). Although RNS can kill Mtb under some circumstances, Mtb can adapt and survive in the presence of RNS by a process that involves modulation of gene expression. Previous studies focused primarily on stress-related changes in the Mtb transcriptome. This study unveils changes in the Mtb proteome in response to a sub-lethal dose of nitric oxide (NO) over several hours of exposure. Proteins were identified using liquid chromatography coupled with electrospray ionization mass spectrometry (LC-MS/MS). A total of 2911 Mtb proteins were identified, of which 581 were differentially abundant (DA) after exposure to NO in at least one of the four time points (30 min, 2 h, 6 h, and 20 h). The proteomic response to NO was marked by two phases, with few DA proteins in the early phase and a multitude of DA proteins in the later phase. The efflux pump Rv1687 stood out as being the only protein more abundant at all the time points and might play a role in the early protection of Mtb against nitrosative stress. These changes appeared to be compensatory in nature, contributing to iron homeostasis, energy metabolism, and other stress responses. This study thereby provides new insights into the response of Mtb to NO at the level of proteomics.
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Affiliation(s)
- Alemayehu Godana Birhanu
- Department
of Microbiology, University of Oslo, P.O. Box 4950, Nydalen, NO-0424 Oslo, Norway
- Institute
of Biotechnology, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia
| | - Marta Gómez-Muñoz
- Department
of Microbiology, University of Oslo, P.O. Box 4950, Nydalen, NO-0424 Oslo, Norway
| | - Shewit Kalayou
- Department
of Microbiology, Oslo University Hospital, P.O. Box 4950, Nydalen, NO-0424 Oslo, Norway
- International
Center of Insect Physiology and Ecology (ICIPE), P.O. Box 30772-00100 Nairobi, Kenya
| | - Tahira Riaz
- Department
of Microbiology, University of Oslo, P.O. Box 4950, Nydalen, NO-0424 Oslo, Norway
| | - Timo Lutter
- Department
of Microbiology, University of Oslo, P.O. Box 4950, Nydalen, NO-0424 Oslo, Norway
| | - Solomon Abebe Yimer
- Department
of Microbiology, University of Oslo, P.O. Box 4950, Nydalen, NO-0424 Oslo, Norway
- Coalition
for Epidemic Preparedness Innovations (CEPI), P.O. Box 123, Torshov, 0412 Oslo, Norway
| | - Markos Abebe
- Armauer
Hansen Research Institute, Jimma Road, P.O. Box 1005 Addis Ababa, Ethiopia
| | - Tone Tønjum
- Department
of Microbiology, University of Oslo, P.O. Box 4950, Nydalen, NO-0424 Oslo, Norway
- Department
of Microbiology, Oslo University Hospital, P.O. Box 4950, Nydalen, NO-0424 Oslo, Norway
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11
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Proteins from the core genome of Corynebacterium ulcerans respond for pathogenicity and reveal promising vaccine targets for diphtheria. Microb Pathog 2021; 161:105263. [PMID: 34687839 DOI: 10.1016/j.micpath.2021.105263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 10/14/2021] [Accepted: 10/19/2021] [Indexed: 11/23/2022]
Abstract
Corynebacterium ulcerans is an emerging pathogen able to transmit the acute infection diphtheria to humans. Although there is a well-established vaccine based on the toxin produced by Corynebacterium diphtheriae, another species of this genus known to cause the disease, there is still no vaccine formulations described for C. ulcerans; this fact contributes to the increase in cases of infection that has been observed. In this study, we want to provide information at the genomic level of this bacterium in order to suggest proteins as possible vaccine targets. We carried out an in silico prospection of vaccine candidates through reverse vaccinology for targets that exhibit antigenic potential against diphtheria. We found important virulence factors, such as adhesion-related ones, that are responsible for pathogen-host interaction after infection, but we did not find the diphtheria toxin, which is the main component of the currently available vaccine. This study provides detailed information about the exoproteome and hypothetical proteins from the core genome of C. ulcerans, suggesting vaccine targets to be further tested in vitro for the development of a new vaccine against diphtheria.
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12
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Matilla MA, Velando F, Martín-Mora D, Monteagudo-Cascales E, Krell T. A catalogue of signal molecules that interact with sensor kinases, chemoreceptors and transcriptional regulators. FEMS Microbiol Rev 2021; 46:6356564. [PMID: 34424339 DOI: 10.1093/femsre/fuab043] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 08/10/2021] [Indexed: 12/12/2022] Open
Abstract
Bacteria have evolved many different signal transduction systems that sense signals and generate a variety of responses. Generally, most abundant are transcriptional regulators, sensor histidine kinases and chemoreceptors. Typically, these systems recognize their signal molecules with dedicated ligand-binding domains (LBDs), which, in turn, generate a molecular stimulus that modulates the activity of the output module. There are an enormous number of different LBDs that recognize a similarly diverse set of signals. To give a global perspective of the signals that interact with transcriptional regulators, sensor kinases and chemoreceptors, we manually retrieved information on the protein-ligand interaction from about 1,200 publications and 3D structures. The resulting 811 proteins were classified according to the Pfam family into 127 groups. These data permit a delineation of the signal profiles of individual LBD families as well as distinguishing between families that recognize signals in a promiscuous manner and those that possess a well-defined ligand range. A major bottleneck in the field is the fact that the signal input of many signaling systems is unknown. The signal repertoire reported here will help the scientific community design experimental strategies to identify the signaling molecules for uncharacterised sensor proteins.
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Affiliation(s)
- Miguel A Matilla
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Prof. Albareda 1, 18008 Granada, Spain
| | - Félix Velando
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Prof. Albareda 1, 18008 Granada, Spain
| | - David Martín-Mora
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Prof. Albareda 1, 18008 Granada, Spain
| | - Elizabet Monteagudo-Cascales
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Prof. Albareda 1, 18008 Granada, Spain
| | - Tino Krell
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Prof. Albareda 1, 18008 Granada, Spain
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13
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Maurya R, Kanakan A, Vasudevan JS, Chattopadhyay P, Pandey R. Infection outcome needs two to tango: human host and the pathogen. Brief Funct Genomics 2021; 21:90-102. [PMID: 34402498 PMCID: PMC8385967 DOI: 10.1093/bfgp/elab037] [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] [Received: 06/15/2021] [Revised: 07/15/2021] [Accepted: 07/21/2021] [Indexed: 12/15/2022] Open
Abstract
Infectious diseases are potential drivers for human evolution, through a complex, continuous and dynamic interaction between the host and the pathogen/s. It is this dynamic interaction that contributes toward the clinical outcome of a pathogenic disease. These are modulated by contributions from the human genetic variants, transcriptional response (including noncoding RNA) and the pathogen’s genome architecture. Modern genomic tools and techniques have been crucial for the detection and genomic characterization of pathogens with respect to the emerging infectious diseases. Aided by next-generation sequencing (NGS), risk stratification of host population/s allows for the identification of susceptible subgroups and better disease management. Nevertheless, many challenges to a general understanding of host–pathogen interactions remain. In this review, we elucidate how a better understanding of the human host-pathogen interplay can substantially enhance, and in turn benefit from, current and future applications of multi-omics based approaches in infectious and rare diseases. This includes the RNA-level response, which modulates the disease severity and outcome. The need to understand the role of human genetic variants in disease severity and clinical outcome has been further highlighted during the Coronavirus disease 2019 (COVID-19) pandemic. This would enhance and contribute toward our future pandemic preparedness.
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Affiliation(s)
- Ranjeet Maurya
- INtegrative GENomics of HOst-PathogEn (INGEN-HOPE) laboratory, CSIR-Institute of Genomics and Integrative Biology (CSIR-IGIB), Mall Road, Delhi-110007, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
| | - Akshay Kanakan
- INtegrative GENomics of HOst-PathogEn (INGEN-HOPE) laboratory, CSIR-Institute of Genomics and Integrative Biology (CSIR-IGIB), Mall Road, Delhi-110007, India
| | - Janani Srinivasa Vasudevan
- INtegrative GENomics of HOst-PathogEn (INGEN-HOPE) laboratory, CSIR-Institute of Genomics and Integrative Biology (CSIR-IGIB), Mall Road, Delhi-110007, India
| | - Partha Chattopadhyay
- INtegrative GENomics of HOst-PathogEn (INGEN-HOPE) laboratory, CSIR-Institute of Genomics and Integrative Biology (CSIR-IGIB), Mall Road, Delhi-110007, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
| | - Rajesh Pandey
- INtegrative GENomics of HOst-PathogEn (INGEN-HOPE) laboratory, CSIR-Institute of Genomics and Integrative Biology (CSIR-IGIB), Mall Road, Delhi-110007, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
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14
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Hariharan VN, Yadav R, Thakur C, Singh A, Gopinathan R, Singh DP, Sankhe G, Malhotra V, Chandra N, Bhatt A, Saini DK. Cyclic di-GMP sensing histidine kinase PdtaS controls mycobacterial adaptation to carbon sources. FASEB J 2021; 35:e21475. [PMID: 33772870 DOI: 10.1096/fj.202002537rr] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 02/09/2021] [Accepted: 02/10/2021] [Indexed: 11/11/2022]
Abstract
Cell signaling relies on second messengers to transduce signals from the sensory apparatus to downstream signaling pathway components. In bacteria, one of the most important and ubiquitous second messenger is the small molecule cyclic diguanosine monophosphate (c-di-GMP). While the biosynthesis, degradation, and regulatory pathways controlled by c-di-GMP are well characterized, the mechanisms through which c-di-GMP controls these processes are not entirely understood. Herein we present the report of a c-di-GMP sensing sensor histidine kinase PdtaS (Rv3220c), which binds to c-di-GMP at submicromolar concentrations, subsequently perturbing signaling of the PdtaS-PdtaR (Rv1626) two-component system. Aided by biochemical analysis, genetics, molecular docking, FRET microscopy, and structural modelling, we have characterized the binding of c-di-GMP in the GAF domain of PdtaS. We show that a pdtaS knockout in Mycobacterium smegmatis is severely compromised in growth on amino acid deficient media and exhibits global transcriptional dysregulation. The perturbation of the c-di-GMP-PdtaS-PdtaR axis results in a cascade of cellular changes recorded by a multiparametric systems' approach of transcriptomics, unbiased metabolomics, and lipid analyses.
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Affiliation(s)
- Vignesh Narayan Hariharan
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, India
| | - Rahul Yadav
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, India
| | - Chandrani Thakur
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Albel Singh
- School of Biosciences and Institute of Microbiology and Infection, University of Birmingham, Birmingham, UK
| | - Renu Gopinathan
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, India
| | - Devendra Pratap Singh
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, India
| | - Gaurav Sankhe
- Centre for Biosystems Science and Engineering, Indian Institute of Science, Bangalore, India
| | - Vandana Malhotra
- Department of Biochemistry, Sri Venkateswara College, Delhi University, Delhi, India
| | - Nagasuma Chandra
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Apoorva Bhatt
- School of Biosciences and Institute of Microbiology and Infection, University of Birmingham, Birmingham, UK
| | - Deepak Kumar Saini
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bangalore, India.,Centre for Biosystems Science and Engineering, Indian Institute of Science, Bangalore, India
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15
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Khan MZ, Singha B, Ali MF, Taunk K, Rapole S, Gourinath S, Nandicoori VK. Redox homeostasis in Mycobacterium tuberculosis is modulated by a novel actinomycete-specific transcription factor. EMBO J 2021; 40:e106111. [PMID: 34018220 PMCID: PMC8280819 DOI: 10.15252/embj.2020106111] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 04/17/2021] [Accepted: 04/20/2021] [Indexed: 11/09/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb) has evolved diverse cellular processes in response to the multiple stresses it encounters within the infected host. We explored available TnSeq datasets to identify transcription factors (TFs) that are essential for Mtb survival inside the host. The analysis identified a single TF, Rv1332 (AosR), conserved across actinomycetes with a so‐far uncharacterized function. AosR mitigates phagocyte‐derived oxidative and nitrosative stress, thus promoting mycobacterial growth in the murine lungs and spleen. Oxidative stress induces formation of a single intrasubunit disulphide bond in AosR, which in turn facilitates AosR interaction with an extracytoplasmic‐function sigma factor, SigH. This leads to the specific upregulation of the CysM‐dependent non‐canonical cysteine biosynthesis pathway through an auxiliary intragenic stress‐responsive promoter, an axis critical in detoxifying host‐derived oxidative and nitrosative radicals. Failure to upregulate AosR‐dependent cysteine biosynthesis during the redox stress causes differential expression of 6% of Mtb genes. Our study shows that the AosR‐SigH pathway is critical for detoxifying host‐derived oxidative and nitrosative radicals to enhance Mtb survival in the hostile intracellular environment.
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16
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Bajeli S, Baid N, Kaur M, Pawar GP, Chaudhari VD, Kumar A. Terminal Respiratory Oxidases: A Targetables Vulnerability of Mycobacterial Bioenergetics? Front Cell Infect Microbiol 2020; 10:589318. [PMID: 33330134 PMCID: PMC7719681 DOI: 10.3389/fcimb.2020.589318] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 10/20/2020] [Indexed: 12/12/2022] Open
Abstract
Recently, ATP synthase inhibitor Bedaquiline was approved for the treatment of multi-drug resistant tuberculosis emphasizing the importance of oxidative phosphorylation for the survival of mycobacteria. ATP synthesis is primarily dependent on the generation of proton motive force through the electron transport chain in mycobacteria. The mycobacterial electron transport chain utilizes two terminal oxidases for the reduction of oxygen, namely the bc1-aa3 supercomplex and the cytochrome bd oxidase. The bc1-aa3 supercomplex is an energy-efficient terminal oxidase that pumps out four vectoral protons, besides consuming four scalar protons during the transfer of electrons from menaquinone to molecular oxygen. In the past few years, several inhibitors of bc1-aa3 supercomplex have been developed, out of which, Q203 belonging to the class of imidazopyridine, has moved to clinical trials. Recently, the crystal structure of the mycobacterial cytochrome bc1-aa3 supercomplex was solved, providing details of the route of transfer of electrons from menaquinone to molecular oxygen. Besides providing insights into the molecular functioning, crystal structure is aiding in the targeted drug development. On the other hand, the second respiratory terminal oxidase of the mycobacterial respiratory chain, cytochrome bd oxidase, does not pump out the vectoral protons and is energetically less efficient. However, it can detoxify the reactive oxygen species and facilitate mycobacterial survival during a multitude of stresses. Quinolone derivatives (CK-2-63) and quinone derivative (Aurachin D) inhibit cytochrome bd oxidase. Notably, ablation of both the two terminal oxidases simultaneously through genetic methods or pharmacological inhibition leads to the rapid death of the mycobacterial cells. Thus, terminal oxidases have emerged as important drug targets. In this review, we have described the current understanding of the functioning of these two oxidases, their physiological relevance to mycobacteria, and their inhibitors. Besides these, we also describe the alternative terminal complexes that are used by mycobacteria to maintain energized membrane during hypoxia and anaerobic conditions.
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Affiliation(s)
- Sapna Bajeli
- Molecular Mycobacteriology, Council of Scientific and Industrial Research, Institute of Microbial Technology, Chandigarh, India
| | - Navin Baid
- Molecular Mycobacteriology, Council of Scientific and Industrial Research, Institute of Microbial Technology, Chandigarh, India
| | - Manjot Kaur
- Division of Medicinal Chemistry, Council of Scientific and Industrial Research, Institute of Microbial Technology, Chandigarh, India
| | - Ganesh P Pawar
- Division of Medicinal Chemistry, Council of Scientific and Industrial Research, Institute of Microbial Technology, Chandigarh, India
| | - Vinod D Chaudhari
- Division of Medicinal Chemistry, Council of Scientific and Industrial Research, Institute of Microbial Technology, Chandigarh, India
| | - Ashwani Kumar
- Molecular Mycobacteriology, Council of Scientific and Industrial Research, Institute of Microbial Technology, Chandigarh, India
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17
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Sousa EH, Carepo MS, Moura JJ. Nitrate-nitrite fate and oxygen sensing in dormant Mycobacterium tuberculosis: A bioinorganic approach highlighting the importance of transition metals. Coord Chem Rev 2020. [DOI: 10.1016/j.ccr.2020.213476] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
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18
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Potential therapeutic approaches for a sleeping pathogen: tuberculosis a case for bioinorganic chemistry. J Biol Inorg Chem 2020; 25:685-704. [PMID: 32676771 DOI: 10.1007/s00775-020-01803-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 06/30/2020] [Indexed: 12/18/2022]
Abstract
Mycobacterium tuberculosis (Mtb) has an old history as a human pathogen and still kills over one million people every year. One key feature of this bacterium is its dormancy: a phenomenon responsible for major changes in its metabolism and replication that have been associated with the need for a lengthy therapy for Mtb. This process is regulated by key heme-based sensors, particularly DosT and DevS (DosS), among other co-regulators, and also linked to nitrogen utilization (nitrate/nitrite) and stringent responses. In face of the current threat of tuberculosis, there is an urgent need to develop new therapeutic agents capable of targeting the dormant state, associated with the need for a lengthy therapy. Interestingly, many of those key proteins are indeed metallo-containing or metallo-dependent biomolecules, opening exciting bioinorganic opportunities. Here, we critically reviewed a series of small molecules targeting key proteins involved in these processes, including DosT/DevS/DevR, RegX3, MprA, MtrA, NarL, PknB, Rel, PPK, nitrate and nitrite reductases, GlnA1, aiming for new opportunities and alternative therapies. In the battle against Mycobacterium tuberculosis, new drug targets must be searched, in particular those involved in dormancy. A series of exciting cases for drug development involving metallo-containing or metallo-dependent biomolecules are reviewed, opening great opportunities for the bioinorganic chemistry community.
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19
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Mavi PS, Singh S, Kumar A. Reductive Stress: New Insights in Physiology and Drug Tolerance of Mycobacterium. Antioxid Redox Signal 2020; 32:1348-1366. [PMID: 31621379 DOI: 10.1089/ars.2019.7867] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Significance:Mycobacterium tuberculosis (Mtb) encounters reductive stress during its infection cycle. Notably, host-generated protective responses, such as acidic pH inside phagosomes and lysosomes, exposure to glutathione in alveolar hypophase (i.e., a thin liquid lining consisting of surfactant and proteins in the alveolus), and hypoxic environments inside granulomas are associated with the accumulation of reduced cofactors, such as nicotinamide adenine dinucleotide (reduced form), nicotinamide adenine dinucleotide phosphate, flavin adenine dinucleotide (reduced form), and nonprotein thiols (e.g., mycothiol), leading to reductive stress in Mtb cells. Dissipation of this reductive stress is important for survival of the bacterium. If reductive stress is not dissipated, it leads to generation of reactive oxygen species, which may be fatal for the cells. Recent Advances: This review focuses on mechanisms utilized by mycobacteria to sense and respond to reductive stress. Importantly, exposure of Mtb cells to reductive stress leads to growth inhibition, altered metabolism, modulation of virulence, and drug tolerance. Mtb is equipped with thiol buffering systems of mycothiol and ergothioneine to protect itself from various redox stresses. These systems are complemented by thioredoxin and thioredoxin reductase (TR) systems for maintaining cellular redox homeostasis. A diverse array of sensors is used by Mycobacterium for monitoring its intracellular redox status. Upon sensing reductive stress, Mtb uses a flexible and robust metabolic system for its dissipation. Branched electron transport chain allows Mycobacterium to function with different terminal electron acceptors and modulate proton motive force to fulfill energy requirements under diverse scenarios. Interestingly, Mtb utilizes variations in the tricarboxylic cycle and a number of dehydrogenases to dissipate reductive stress. Upon prolonged exposure to reductive stress, Mtb utilizes biosynthesis of storage and virulence lipids as a dissipative mechanism. Critical Issues: The mechanisms utilized by Mycobacterium for sensing and tackling reductive stress are not well characterized. Future Directions: The precise role of thiol buffering and TR systems in neutralizing reductive stress is not well defined. Genetic systems that respond to metabolic reductive stress and thiol reductive stress need to be mapped. Genetic screens could aid in identification of such systems. Given that management of reductive stress is critical for both actively replicating and persister mycobacteria, an improved understanding of the mechanisms used by mycobacteria for dissipation of reductive stress may lead to identification of vulnerable choke points that could be targeted for killing Mtb in vivo.
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Affiliation(s)
- Parminder Singh Mavi
- Institute of Microbial Technology, Council of Scientific and Industrial Research, Chandigarh, India
| | - Shweta Singh
- Institute of Microbial Technology, Council of Scientific and Industrial Research, Chandigarh, India
| | - Ashwani Kumar
- Institute of Microbial Technology, Council of Scientific and Industrial Research, Chandigarh, India.,Academy of Scientific and Innovative Research, Ghaziabad, India
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20
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Park EJ, Kwon YM, Lee JW, Kang HY, Oh JI. Dual control of RegX3 transcriptional activity by SenX3 and PknB. J Biol Chem 2019; 294:11023-11034. [PMID: 31160336 DOI: 10.1074/jbc.ra119.008232] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 05/30/2019] [Indexed: 01/08/2023] Open
Abstract
The mycobacterial SenX3-RegX3 two-component system consists of the SenX3 sensor histidine kinase and its cognate RegX3 response regulator. This system is a phosphorelay-based regulatory system involved in sensing environmental Pi levels and induction of genes required for Pi acquisition under Pi-limiting conditions. Here we demonstrate that overexpression of the kinase domain of Mycobacterium tuberculosis PknB (PknB-KDMtb) inhibits the transcriptional activity of RegX3 of both M. tuberculosis and Mycobacterium smegmatis (RegX3Mtb and RegX3Ms, respectively). Mass spectrometry results, along with those of in vitro phosphorylation and complementation analyses, revealed that PknB kinase activity inhibits the transcriptional activity of RegX3Mtb through phosphorylation events at Thr-100, Thr-191, and Thr-217. Electrophoretic mobility shift assays disclosed that phosphorylation of Thr-191 and Thr-217 abolishes the DNA-binding ability of RegX3Mtb and that Thr-100 phosphorylation likely prevents RegX3Mtb from being activated through conformational changes induced by SenX3-mediated phosphorylation. We propose that the convergence of the PknB and SenX3-RegX3 signaling pathways might enable mycobacteria to integrate environmental Pi signals with the cellular replication state to adjust gene expression in response to Pi availability.
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Affiliation(s)
- Eun-Jin Park
- Department of Microbiology, Pusan National University, Busan 46241, Republic of Korea
| | - Yu-Mi Kwon
- Biomedical Research Institute, Center for Theragnosis, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea, and; Department of Life Science and Research Institute for Natural Sciences, Hanyang University, Seoul 04763, Republic of Korea
| | - Jin-Won Lee
- Department of Life Science and Research Institute for Natural Sciences, Hanyang University, Seoul 04763, Republic of Korea
| | - Ho-Young Kang
- Department of Microbiology, Pusan National University, Busan 46241, Republic of Korea
| | - Jeong-Il Oh
- Department of Microbiology, Pusan National University, Busan 46241, Republic of Korea,.
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21
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Araújo CL, Alves J, Nogueira W, Pereira LC, Gomide AC, Ramos R, Azevedo V, Silva A, Folador A. Prediction of new vaccine targets in the core genome of Corynebacterium pseudotuberculosis through omics approaches and reverse vaccinology. Gene 2019; 702:36-45. [PMID: 30928361 DOI: 10.1016/j.gene.2019.03.049] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 03/15/2019] [Accepted: 03/21/2019] [Indexed: 12/11/2022]
Abstract
Corynebacterium pseudotuberculosis is the etiologic agent of veterinary relevance diseases, such as caseous lymphadenitis, affecting different animal species causing damage to the global agribusiness. So far, there are no completely effective treatment methods to overcome the impacts caused by this pathogen. Several genomes of the species are deposited on public databases, allowing the execution of studies related to the pan-genomic approach. In this study, we used an integrated in silico workflow to prospect novel putative targets using the core genome, a set of shared genes among 65 C. pseudotuberculosis strains. Subsequently, through RNA-Seq data of the same abiotic stresses in two strains, we selected only induced genes to compose the reverse vaccinology workflow based in two different strategies. Our results predicted six probable antigens in both analysis, which indicates that they have a strong potential to be used in further studies as vaccine targets against this bacterium.
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Affiliation(s)
- Carlos Leonardo Araújo
- Laboratory of Genomics and Bioinformatics, Center of Genomics and System Biology, Federal University of Pará, Belém, Pará, Brazil
| | - Jorianne Alves
- Laboratory of Genomics and Bioinformatics, Center of Genomics and System Biology, Federal University of Pará, Belém, Pará, Brazil
| | - Wylerson Nogueira
- Department of General Biology, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Lino César Pereira
- Laboratory of Genomics and Bioinformatics, Center of Genomics and System Biology, Federal University of Pará, Belém, Pará, Brazil
| | - Anne Cybelle Gomide
- Department of General Biology, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Rommel Ramos
- Laboratory of Genomics and Bioinformatics, Center of Genomics and System Biology, Federal University of Pará, Belém, Pará, Brazil
| | - Vasco Azevedo
- Department of General Biology, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Artur Silva
- Laboratory of Genomics and Bioinformatics, Center of Genomics and System Biology, Federal University of Pará, Belém, Pará, Brazil
| | - Adriana Folador
- Laboratory of Genomics and Bioinformatics, Center of Genomics and System Biology, Federal University of Pará, Belém, Pará, Brazil.
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22
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Mehta M, Singh A. Mycobacterium tuberculosis WhiB3 maintains redox homeostasis and survival in response to reactive oxygen and nitrogen species. Free Radic Biol Med 2019; 131:50-58. [PMID: 30500421 PMCID: PMC6635127 DOI: 10.1016/j.freeradbiomed.2018.11.032] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Revised: 10/30/2018] [Accepted: 11/26/2018] [Indexed: 12/20/2022]
Abstract
Mycobacterium tuberculosis (Mtb) survives under oxidatively and nitosatively hostile niches inside host phagocytes. In other bacteria, adaptation to these stresses is dependent upon the redox sensitive two component systems (e.g., ArcAB) and transcription factors (e.g., FNR/SoxR). However, these factors are absent in Mtb. Therefore, it is not completely understood how Mtb maintains survival and redox balance in response to reactive oxygen species (ROS) and reactive nitrogen species (RNS). Here, we present evidences that a 4Fe-4S-cofactor containing redox-sensitive transcription factor (WhiB3) is exploited by Mtb to adapt under ROS and RNS stress. We show that MtbΔwhiB3 is acutely sensitive to oxidants and to nitrosative agents. Using a genetic biosensor of cytoplasmic redox state (Mrx1-roGFP2) of Mtb, we show that WhiB3 facilitates recovery from ROS (cumene hydroperoxide and hydrogen peroxide) and RNS (acidified nitrite and peroxynitrite). Also, MtbΔwhiB3 displayed reduced survival inside RAW 264.7 macrophages. Consistent with the role of WhiB3 in modulating host-pathogen interaction, we discovered that WhiB3 coordinates the formation of early human granulomas during interaction of Mtb with human peripheral blood mononuclear cells (PBMCs). Altogether, our study provides empirical proof that WhiB3 is required to mitigate redox stress induced by ROS and RNS, which may be important to activate host/bacterial pathways required for the granuloma development and maintenance.
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Affiliation(s)
- Mansi Mehta
- Microbiology and Cell Biology, Centre for Infectious Disease Research (CIDR), Indian Institute of Science (IISc), CV Raman Av, Bangalore 12, India
| | - Amit Singh
- Microbiology and Cell Biology, Centre for Infectious Disease Research (CIDR), Indian Institute of Science (IISc), CV Raman Av, Bangalore 12, India.
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23
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Chakraborty P, Kumar A. The extracellular matrix of mycobacterial biofilms: could we shorten the treatment of mycobacterial infections? MICROBIAL CELL 2019; 6:105-122. [PMID: 30740456 PMCID: PMC6364259 DOI: 10.15698/mic2019.02.667] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A number of non-tuberculous mycobacterium species are opportunistic pathogens and ubiquitously form biofilms. These infections are often recalcitrant to treatment and require therapy with multiple drugs for long duration. The biofilm resident bacteria also display phenotypic drug tolerance and thus it has been hypothesized that the drug unresponsiveness in vivo could be due to formation of biofilms inside the host. We have discussed the biofilms of several pathogenic non-tuberculous mycobacterium (NTM) species in context to the in vivo pathologies. Besides pathogenic NTMs, Mycobacterium smegmatis is often used as a model organism for understanding mycobacterial physiology and has been studied extensively for understanding the mycobacterial biofilms. A number of components of the mycobacterial cell wall such as glycopeptidolipids, short chain mycolic acids, monomeromycolyl diacylglycerol, etc. have been shown to play an important role in formation of pellicle biofilms. It shall be noted that these components impart a hydrophobic character to the mycobacterial cell surface that facilitates cell to cell interaction. However, these components are not necessarily the constituents of the extracellular matrix of mycobacterial biofilms. In the end, we have described the biofilms of Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis. Three models of Mtb biofilm formation have been proposed to study the factors regulating biofilm formation, the physiology of the resident bacteria, and the nature of the biomaterial that holds these bacterial masses together. These models include pellicle biofilms formed at the liquid-air interface of cultures, leukocyte lysate-induced biofilms, and thiol reductive stressinduced biofilms. All the three models offer their own advantages in the study of Mtb biofilms. Interestingly, lipids (mainly keto-mycolic acids) are proposed to be the primary component of extracellular polymeric substance (EPS) in the pellicle biofilm, whereas the leukocyte lysate-induced and thiol reductive stress-induced biofilms possess polysaccharides as the primary component of EPS. Both models also contain extracellular DNA in the EPS. Interestingly, thiol reductive stressinduced Mtb biofilms are held together by cellulose and yet unidentified structural proteins. We believe that a better understanding of the EPS of Mtb biofilms and the physiology of the resident bacteria will facilitate the development of shorter regimen for TB treatment.
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Affiliation(s)
- Poushali Chakraborty
- Council of Scientific and Industrial Research, Institute of Microbial Technology, Chandigarh, India 160036
| | - Ashwani Kumar
- Council of Scientific and Industrial Research, Institute of Microbial Technology, Chandigarh, India 160036.,CSIR-Academy of Scientific & Innovative Research (AcSIR), Council of Scientific & Industrial Research, New Delhi-110001
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24
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Lobão JBDS, Gondim ACS, Guimarães WG, Gilles‐Gonzalez M, Lopes LGDF, Sousa EHS. Oxygen triggers signal transduction in the DevS (DosS) sensor of
Mycobacterium tuberculosis
by modulating the quaternary structure. FEBS J 2019; 286:479-494. [DOI: 10.1111/febs.14734] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2018] [Revised: 11/05/2018] [Accepted: 12/14/2018] [Indexed: 12/12/2022]
Affiliation(s)
- Josiane Bezerra da Silva Lobão
- Laboratory of Bioinorganic Chemistry Department of Organic and Inorganic Chemistry Federal University of Ceara Center for Sciences Fortaleza Brazil
| | - Ana C. S. Gondim
- Laboratory of Bioinorganic Chemistry Department of Organic and Inorganic Chemistry Federal University of Ceara Center for Sciences Fortaleza Brazil
| | - Wellinson G. Guimarães
- Laboratory of Bioinorganic Chemistry Department of Organic and Inorganic Chemistry Federal University of Ceara Center for Sciences Fortaleza Brazil
| | | | - Luiz Gonzaga de França Lopes
- Laboratory of Bioinorganic Chemistry Department of Organic and Inorganic Chemistry Federal University of Ceara Center for Sciences Fortaleza Brazil
| | - Eduardo H. S. Sousa
- Laboratory of Bioinorganic Chemistry Department of Organic and Inorganic Chemistry Federal University of Ceara Center for Sciences Fortaleza Brazil
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Pacl HT, Reddy VP, Saini V, Chinta KC, Steyn AJC. Host-pathogen redox dynamics modulate Mycobacterium tuberculosis pathogenesis. Pathog Dis 2018; 76:4972762. [PMID: 29873719 PMCID: PMC5989597 DOI: 10.1093/femspd/fty036] [Citation(s) in RCA: 18] [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: 02/09/2018] [Accepted: 04/13/2018] [Indexed: 12/18/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, encounters variable and hostile environments within the host. A major component of these hostile conditions is reductive and oxidative stresses induced by factors modified by the host immune response, such as oxygen tension, NO or CO gases, reactive oxygen and nitrogen intermediates, the availability of different carbon sources and changes in pH. It is therefore essential for Mtb to continuously monitor and appropriately respond to the microenvironment. To this end, Mtb has developed various redox-sensitive systems capable of monitoring its intracellular redox environment and coordinating a response essential for virulence. Various aspects of Mtb physiology are regulated by these systems, including drug susceptibility, secretion systems, energy metabolism and dormancy. While great progress has been made in understanding the mechanisms and pathways that govern the response of Mtb to the host's redox environment, many questions in this area remain unanswered. The answers to these questions are promising avenues for addressing the tuberculosis crisis.
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Affiliation(s)
- Hayden T Pacl
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 35205, USA
| | - Vineel P Reddy
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 35205, USA
| | - Vikram Saini
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 35205, USA
| | - Krishna C Chinta
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 35205, USA
| | - Adrie J C Steyn
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 35205, USA
- Centers for AIDS Research and Free Radical Biology, University of Alabama at Birmingham, Birmingham, Alabama 35205, USA
- Africa Health Research Institute, K-RITH Tower Building, Durban 4001, South Africa
- School of Laboratory Medicine and Medical Sciences, Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban 4001, South Africa
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Kundu M. The role of two-component systems in the physiology of Mycobacterium tuberculosis. IUBMB Life 2018; 70:710-717. [PMID: 29885211 DOI: 10.1002/iub.1872] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 04/22/2018] [Indexed: 12/14/2022]
Abstract
Tuberculosis is a global health problem, with a third of the world's population infected with the bacillus, Mycobacterium tuberculosis. The problem is exacerbated by the emergence of multidrug resistant and extensively drug resistant strains. The search for new drug targets is therefore a priority for researchers in the field. The two-component systems (TCSs) are central to the ability of the bacterium to sense and to respond appropriately to its environment. Here we summarize current knowledge on the paired TCSs of M. tuberculosis. We discuss what is currently understood regarding the signals to which each of the sensor kinases responds, and the regulons of each of the cognate response regulators. We also discuss what is known regarding attempts to inhibit the TCSs by small molecules and project their potential as pharmacological targets for the development of novel antimycobacterial agents. © 2018 IUBMB Life, 70(8):710-717, 2018.
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Iqbal IK, Bajeli S, Akela AK, Kumar A. Bioenergetics of Mycobacterium: An Emerging Landscape for Drug Discovery. Pathogens 2018; 7:E24. [PMID: 29473841 PMCID: PMC5874750 DOI: 10.3390/pathogens7010024] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 01/29/2018] [Accepted: 01/31/2018] [Indexed: 11/16/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb) exhibits remarkable metabolic flexibility that enables it to survive a plethora of host environments during its life cycle. With the advent of bedaquiline for treatment of multidrug-resistant tuberculosis, oxidative phosphorylation has been validated as an important target and a vulnerable component of mycobacterial metabolism. Exploiting the dependence of Mtb on oxidative phosphorylation for energy production, several components of this pathway have been targeted for the development of new antimycobacterial agents. This includes targeting NADH dehydrogenase by phenothiazine derivatives, menaquinone biosynthesis by DG70 and other compounds, terminal oxidase by imidazopyridine amides and ATP synthase by diarylquinolines. Importantly, oxidative phosphorylation also plays a critical role in the survival of persisters. Thus, inhibitors of oxidative phosphorylation can synergize with frontline TB drugs to shorten the course of treatment. In this review, we discuss the oxidative phosphorylation pathway and development of its inhibitors in detail.
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Affiliation(s)
- Iram Khan Iqbal
- Council of Scientific and Industrial Research, Institute of Microbial Technology, Chandigarh 160036, India.
| | - Sapna Bajeli
- Council of Scientific and Industrial Research, Institute of Microbial Technology, Chandigarh 160036, India.
| | - Ajit Kumar Akela
- Council of Scientific and Industrial Research, Institute of Microbial Technology, Chandigarh 160036, India.
| | - Ashwani Kumar
- Council of Scientific and Industrial Research, Institute of Microbial Technology, Chandigarh 160036, India.
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28
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Drug discovery targeting heme-based sensors and their coupled activities. J Inorg Biochem 2017; 167:12-20. [DOI: 10.1016/j.jinorgbio.2016.11.022] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 11/08/2016] [Accepted: 11/16/2016] [Indexed: 01/10/2023]
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Abstract
Haem-based sensors have emerged during the last 15 years as being a large family of proteins that occur in all kingdoms of life. These sensors are responsible mainly for detecting binding of O2, CO and NO and reporting the ligation status to an output domain with an enzymatic or macromolecule-binding property. A myriad of biological functions have been associated with these sensors, which are involved in vasodilation, bacterial symbiosis, chemotaxis and biofilm formation, among others. Here, we critically review several bacterial systems for O2 sensing that are extensively studied in many respects, focusing on the lessons that are important to advance the field.
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30
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Bhat SA, Iqbal IK, Kumar A. Imaging the NADH:NAD + Homeostasis for Understanding the Metabolic Response of Mycobacterium to Physiologically Relevant Stresses. Front Cell Infect Microbiol 2016; 6:145. [PMID: 27878107 PMCID: PMC5099167 DOI: 10.3389/fcimb.2016.00145] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 10/21/2016] [Indexed: 11/18/2022] Open
Abstract
The NADH:NAD+ ratio is the primary indicator of the metabolic state of bacteria. NAD(H) homeostasis is critical for Mycobacterium tuberculosis (Mtb) survival and is thus considered an important drug target, but the spatio-temporal measurements of NAD(H) remain a challenge. Genetically encoded fluorescent biosensors of the NADH:NAD+ ratios were recently described, paving the way for investigations of the metabolic state of pathogens during infection. Here we have adapted the genetically encoded biosensor Peredox for measurement of the metabolic state of Mtb in vitro and during infection of macrophage cells. Using Peredox, here we show that inhibition of the electron transport chain, disruption of the membrane potential and proton gradient, exposure to reactive oxygen species and treatment with antimycobacterial drugs led to the accumulation of NADH in mycobacterial cells. We have further demonstrated that Mtb residing in macrophages displays higher NADH:NAD+ ratios, that may indicate a metabolic stress faced by the intracellular Mtb. We also demonstrate that the Mtb residing in macrophages display a metabolic heterogeneity, which may perhaps explain the tolerance displayed by intracellular Mtb. Next we studied the effect of immunological modulation by interferon gamma on metabolism of intracellular Mtb, since macrophage activation is known to restrict mycobacterial growth. We observed that activation of resting macrophages with interferon-gamma results in higher NADH:NAD+ levels in resident Mtb cells. We have further demonstrated that exposure of Isoniazid, Bedaquiline, Rifampicin, and O-floxacin results in higher NADH:NAD+ ratios in the Mtb residing in macrophages. However, intracellular Mtb displays lower NADH:NAD+ ratio upon exposure to clofazimine. In summary, we have generated reporter strains capable of measuring the metabolic state of Mtb cells in vitro and in vivo with spatio-temporal resolution. We believe that this tool will facilitate further studies on mycobacterial physiology and will create new avenues of research for anti-tuberculosis drug discovery.
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Affiliation(s)
- Shabir A Bhat
- Council of Scientific and Industrial Research - Institute of Microbial Technology Chandigarh, India
| | - Iram K Iqbal
- Council of Scientific and Industrial Research - Institute of Microbial Technology Chandigarh, India
| | - Ashwani Kumar
- Council of Scientific and Industrial Research - Institute of Microbial Technology Chandigarh, India
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31
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Chinta KC, Saini V, Glasgow JN, Mazorodze JH, Rahman MA, Reddy D, Lancaster JR, Steyn AJC. The emerging role of gasotransmitters in the pathogenesis of tuberculosis. Nitric Oxide 2016; 59:28-41. [PMID: 27387335 DOI: 10.1016/j.niox.2016.06.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 06/30/2016] [Indexed: 12/17/2022]
Abstract
Mycobacterium tuberculosis (Mtb) is a facultative intracellular pathogen and the second largest contributor to global mortality caused by an infectious agent after HIV. In infected host cells, Mtb is faced with a harsh intracellular environment including hypoxia and the release of nitric oxide (NO) and carbon monoxide (CO) by immune cells. Hypoxia, NO and CO induce a state of in vitro dormancy where Mtb senses these gases via the DosS and DosT heme sensor kinase proteins, which in turn induce a set of ∼47 genes, known as the Mtb Dos dormancy regulon. On the contrary, both iNOS and HO-1, which produce NO and CO, respectively, have been shown to be important against mycobacterial disease progression. In this review, we discuss the impact of O2, NO and CO on Mtb physiology and in host responses to Mtb infection as well as the potential role of another major endogenous gas, hydrogen sulfide (H2S), in Mtb pathogenesis.
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Affiliation(s)
- Krishna C Chinta
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Vikram Saini
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA; UAB Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Joel N Glasgow
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - James H Mazorodze
- KwaZulu-Natal Research Institute for TB and HIV (KRITH), Durban, South Africa
| | - Md Aejazur Rahman
- KwaZulu-Natal Research Institute for TB and HIV (KRITH), Durban, South Africa
| | - Darshan Reddy
- Department of Cardiothoracic Surgery, Nelson R Mandela School of Medicine, University of KwaZulu Natal, Durban, South Africa
| | - Jack R Lancaster
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Adrie J C Steyn
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA; KwaZulu-Natal Research Institute for TB and HIV (KRITH), Durban, South Africa; UAB Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL, USA.
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Mycobacterium tuberculosis Transcription Machinery: Ready To Respond to Host Attacks. J Bacteriol 2016; 198:1360-73. [PMID: 26883824 DOI: 10.1128/jb.00935-15] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Regulating responses to stress is critical for all bacteria, whether they are environmental, commensal, or pathogenic species. For pathogenic bacteria, successful colonization and survival in the host are dependent on adaptation to diverse conditions imposed by the host tissue architecture and the immune response. Once the bacterium senses a hostile environment, it must enact a change in physiology that contributes to the organism's survival strategy. Inappropriate responses have consequences; hence, the execution of the appropriate response is essential for survival of the bacterium in its niche. Stress responses are most often regulated at the level of gene expression and, more specifically, transcription. This minireview focuses on mechanisms of regulating transcription initiation that are required by Mycobacterium tuberculosis to respond to the arsenal of defenses imposed by the host during infection. In particular, we highlight how certain features of M. tuberculosis physiology allow this pathogen to respond swiftly and effectively to host defenses. By enacting highly integrated and coordinated gene expression changes in response to stress,M. tuberculosis is prepared for battle against the host defense and able to persist within the human population.
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