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Pushparajan AR, Edison LK, Ajay Kumar R. Mycobacterium tuberculosis transcriptional regulator Rv1019 is upregulated in hypoxia, and negatively regulates Rv3230c-Rv3229c operon encoding enzymes in the oleic acid biosynthetic pathway. FEBS J 2023; 290:1583-1595. [PMID: 36209365 DOI: 10.1111/febs.16647] [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: 04/25/2022] [Revised: 07/19/2022] [Accepted: 10/05/2022] [Indexed: 11/05/2022]
Abstract
The main obstacle in eradicating tuberculosis is the ability of Mycobacterium tuberculosis to remain dormant in the host, and then to get reactivated even years later under immunocompromised conditions. Transcriptional regulation in intracellular pathogens plays an important role in their adapting to the challenging environment inside the host cells. Previously, we demonstrated that Rv1019, a putative transcriptional regulator of M. tuberculosis H37Rv, is an autorepressor. We showed that Rv1019 is cotranscribed with Rv1020 (mfd) and Rv1021 (mazG) which encode DNA repair proteins and negatively regulates the expression of these genes. In the present study, we show that Rv1019 regulates the expression of the genes Rv3230c and Rv3229c (desA3) also which form a two-gene operon in M. tuberculosis. Overexpression of Rv1019 in M. tuberculosis significantly downregulated the expression of these genes. Employing Wayne's hypoxia-induced dormancy model of M. tuberculosis, we show that Rv1019 is upregulated three-fold under hypoxia. Finally, by reporter assay, using Mycobacterium smegmatis as a model, we validate that Rv1019 is recruited to the promoter of Rv3230c-Rv3229c during hypoxia, and negatively regulates this operon which is involved in the biosynthesis of oleic acid.
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Affiliation(s)
- Akhil Raj Pushparajan
- Mycobacterium Research Laboratory, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, India.,Department of Biotechnology, Faculty of Applied Sciences and Technology, University of Kerala, Thiruvananthapuram, India
| | - Lekshmi K Edison
- Mycobacterium Research Laboratory, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, India
| | - Ramakrishnan Ajay Kumar
- Mycobacterium Research Laboratory, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, India
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2
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Gaglani P, Dwivedi M, Upadhyay TK, Kaushal RS, Ahmad I, Saeed M. A pro-oxidant property of vitamin C to overcome the burden of latent Mycobacterium tuberculosis infection: A cross-talk review with Fenton reaction. Front Cell Infect Microbiol 2023; 13:1152269. [PMID: 37153159 PMCID: PMC10155705 DOI: 10.3389/fcimb.2023.1152269] [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: 01/27/2023] [Accepted: 03/17/2023] [Indexed: 05/09/2023] Open
Abstract
Tuberculosis (TB), caused by the bacillus M. tuberculosis, is one of the deadliest infectious illnesses of our day, along with HIV and malaria.Chemotherapy, the cornerstone of TB control efforts, is jeopardized by the advent of M. tuberculosis strains resistant to many, if not all, of the existing medications.Isoniazid (INH), rifampicin (RIF), pyrazinamide, and ethambutol are used to treat drug-susceptible TB for two months, followed by four months of INH and RIF, but chemotherapy with potentially harmful side effects is sometimes needed to treat multidrug-resistant (MDR) TB for up to two years. Chemotherapy might be greatly shortened by drugs that kill M. tuberculosis more quickly while simultaneously limiting the emergence of drug resistance.Regardless of their intended target, bactericidal medicines commonly kill pathogenic bacteria (gram-negative and gram-positive) by producing hydroxyl radicals via the Fenton reaction.Researchers have concentrated on vitamins with bactericidal properties to address the rising cases globally and have discovered that these vitamins are effective when given along with first-line drugs. The presence of elevated iron content, reactive oxygen species (ROS) generation, and DNA damage all contributed to VC's sterilizing action on M. tb in vitro. Moreover, it has a pleiotropic effect on a variety of biological processes such as detoxification, protein folding - chaperons, cell wall processes, information pathways, regulatory, virulence, metabolism etc.In this review report, the authors extensively discussed the effects of VC on M. tb., such as the generation of free radicals and bactericidal mechanisms with existing treatments, and their further drug development based on ROS production.
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Affiliation(s)
- Pratikkumar Gaglani
- Department of Life Sciences, Parul Institute of Applied Sciences and Biophysics and Structural Biology Laboratory, Center of Research for Development, Parul University, Vadodara, Gujarat, India
| | - Manish Dwivedi
- Amity Institute of Biotechnology, Amity University, Lucknow, Uttar Pradesh, India
| | - Tarun Kumar Upadhyay
- Department of Life Sciences, Parul Institute of Applied Sciences and Animal Cell Culture and Immunobiochemistry Lab, Center of Research for Development, Parul University, Vadodara, Gujarat, India
| | - Radhey Shyam Kaushal
- Department of Life Sciences, Parul Institute of Applied Sciences and Biophysics and Structural Biology Laboratory, Center of Research for Development, Parul University, Vadodara, Gujarat, India
- *Correspondence: Radhey Shyam Kaushal, ; Mohd Saeed,
| | - Irfan Ahmad
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, Abha, Saudi Arabia
| | - Mohd Saeed
- Department of Biology, College of Sciences, University of Hail, Hail, Saudi Arabia
- *Correspondence: Radhey Shyam Kaushal, ; Mohd Saeed,
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3
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Kalra R, Tiwari D, Dkhar HK, Bhagyaraj E, Kumar R, Bhardwaj A, Gupta P. Host factors subverted by Mycobacterium tuberculosis: Potential targets for host directed therapy. Int Rev Immunol 2021; 42:43-70. [PMID: 34678117 DOI: 10.1080/08830185.2021.1990277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
INTRODUCTION Despite new approaches in the diagnosis and treatment of tuberculosis (TB), it continues to be a major health burden. Several immunotherapies that potentiate the immune response have come up as adjuncts to drug therapies against drug resistant TB strains; however, there needs to be an urgent appraisal of host specific drug targets for improving their clinical management and to curtail disease progression. Presently, various host directed therapies (HDTs) exist (repurposed drugs, nutraceuticals, monoclonal antibodies and immunomodulatory agents), but these mostly address molecules that combat disease progression. AREAS COVERED The current review discusses major Mycobacterium tuberculosis (M. tuberculosis) survival paradigms inside the host and presents a plethora of host targets subverted by M. tuberculosis which can be further explored for future HDTs. The host factors unique to M. tuberculosis infection (in humans) have also been identified through an in-silico interaction mapping. EXPERT OPINION HDTs could become the next-generation adjunct therapies in order to counter antimicrobial resistance and virulence, as well as to reduce the duration of existing TB treatments. However, current scientific efforts are largely directed toward combatants rather than host molecules co-opted by M. tuberculosis for its survival. This might drive the immune system to a hyper-inflammatory condition; therefore, we emphasize that host factors subverted by M. tuberculosis, and their subsequent neutralization, must be considered for development of better HDTs.
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Affiliation(s)
- Rashi Kalra
- Department of Molecular Biology, CSIR-Institute of Microbial Technology, Chandigarh-160036, India
| | - Drishti Tiwari
- Department of Molecular Biology, CSIR-Institute of Microbial Technology, Chandigarh-160036, India
| | - Hedwin Kitdorlang Dkhar
- Department of Molecular Biology, CSIR-Institute of Microbial Technology, Chandigarh-160036, India
| | - Ella Bhagyaraj
- Department of Molecular Biology, CSIR-Institute of Microbial Technology, Chandigarh-160036, India
| | - Rakesh Kumar
- Bioinformatics Center, CSIR-Institute of Microbial Technology, Chandigarh-160036, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
| | - Anshu Bhardwaj
- Bioinformatics Center, CSIR-Institute of Microbial Technology, Chandigarh-160036, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
| | - Pawan Gupta
- Department of Molecular Biology, CSIR-Institute of Microbial Technology, Chandigarh-160036, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad-201002, India
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4
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Kundu M, Basu J. Applications of Transcriptomics and Proteomics for Understanding Dormancy and Resuscitation in Mycobacterium tuberculosis. Front Microbiol 2021; 12:642487. [PMID: 33868200 PMCID: PMC8044303 DOI: 10.3389/fmicb.2021.642487] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 02/19/2021] [Indexed: 12/15/2022] Open
Abstract
Mycobacterium tuberculosis can survive within its host for extended periods of time without any clinical symptoms of disease and reactivate when the immune system is weakened. A detailed understanding of how M. tuberculosis enters into and exits out of dormancy, is necessary in order to develop new strategies for tackling tuberculosis. Omics methodologies are unsupervised and unbiased to any hypothesis, making them useful tools for the discovery of new drug targets. This review summarizes the findings of transcriptomic and proteomic approaches toward understanding dormancy and reactivation of M. tuberculosis. Within the granuloma of latently infected individuals, the bacteria are dormant, with a marked slowdown of growth, division and metabolism. In vitro models have attempted to simulate these features by subjecting the bacterium to hypoxia, nutrient starvation, potassium depletion, growth in the presence of vitamin C, or growth in the presence of long-chain fatty acids. The striking feature of all the models is the upregulation of the DosR regulon, which includes the transcriptional regulator Rv0081, one of the central hubs of dormancy. Also upregulated are chaperone proteins, fatty acid and cholesterol degrading enzymes, the sigma factors SigE and SigB, enzymes of the glyoxylate and the methylcitrate cycle, the Clp proteases and the transcriptional regulator ClgR. Further, there is increased expression of genes involved in mycobactin synthesis, fatty acid degradation, the glyoxylate shunt and gluconeogenesis, in granulomas formed in vitro from peripheral blood mononuclear cells from latently infected individuals compared to naïve individuals. Genes linked to aerobic respiration, replication, transcription, translation and cell division, are downregulated during dormancy in vitro, but upregulated during reactivation. Resuscitation in vitro is associated with upregulation of genes linked to the synthesis of mycolic acids, phthiocerol mycocerosate (PDIM) and sulfolipids; ribosome biosynthesis, replication, transcription and translation, cell division, and genes encoding the five resuscitation promoting factors (Rpfs). The expression of proteases, transposases and insertion sequences, suggests genome reorganization during reactivation.
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Affiliation(s)
| | - Joyoti Basu
- Department of Chemistry, Bose Institute, Kolkata, India
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5
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Nandi M, Sikri K, Chaudhary N, Mande SC, Sharma RD, Tyagi JS. Multiple transcription factors co-regulate the Mycobacterium tuberculosis adaptation response to vitamin C. BMC Genomics 2019; 20:887. [PMID: 31752669 PMCID: PMC6868718 DOI: 10.1186/s12864-019-6190-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 10/15/2019] [Indexed: 11/25/2022] Open
Abstract
Background Latent tuberculosis infection is attributed in part to the existence of Mycobacterium tuberculosis in a persistent non-replicating dormant state that is associated with tolerance to host defence mechanisms and antibiotics. We have recently reported that vitamin C treatment of M. tuberculosis triggers the rapid development of bacterial dormancy. Temporal genome-wide transcriptome analysis has revealed that vitamin C-induced dormancy is associated with a large-scale modulation of gene expression in M. tuberculosis. Results An updated transcriptional regulatory network of M.tuberculosis (Mtb-TRN) consisting of 178 regulators and 3432 target genes was constructed. The temporal transcriptome data generated in response to vitamin C was overlaid on the Mtb-TRN (vitamin C Mtb-TRN) to derive insights into the transcriptional regulatory features in vitamin C-adapted bacteria. Statistical analysis using Fisher’s exact test predicted that 56 regulators play a central role in modulating genes which are involved in growth, respiration, metabolism and repair functions. Rv0348, DevR, MprA and RegX3 participate in a core temporal regulatory response during 0.25 h to 8 h of vitamin C treatment. Temporal network analysis further revealed Rv0348 to be the most prominent hub regulator with maximum interactions in the vitamin C Mtb-TRN. Experimental analysis revealed that Rv0348 and DevR proteins interact with each other, and this interaction results in an enhanced binding of DevR to its target promoter. These findings, together with the enhanced expression of devR and Rv0348 transcriptional regulators, indicate a second-level regulation of target genes through transcription factor- transcription factor interactions. Conclusions Temporal regulatory analysis of the vitamin C Mtb-TRN revealed that there is involvement of multiple regulators during bacterial adaptation to dormancy. Our findings suggest that Rv0348 is a prominent hub regulator in the vitamin C model and large-scale modulation of gene expression is achieved through interactions of Rv0348 with other transcriptional regulators.
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Affiliation(s)
- Malobi Nandi
- Department of Biotechnology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India.,Amity Institute of Biotechnology, Amity University, Manesar, Haryana, 122413, India
| | - Kriti Sikri
- Department of Biotechnology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India
| | - Neha Chaudhary
- Department of Biotechnology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India.,Present address: Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE, USA
| | | | - Ravi Datta Sharma
- Amity Institute of Biotechnology, Amity University, Manesar, Haryana, 122413, India
| | - Jaya Sivaswami Tyagi
- Department of Biotechnology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, 110029, India. .,Translational Health Science and Technology Institute, Faridabad, Haryana, 121001, India.
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6
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Batyrshina YR, Schwartz YS. Modeling of Mycobacterium tuberculosis dormancy in bacterial cultures. Tuberculosis (Edinb) 2019; 117:7-17. [DOI: 10.1016/j.tube.2019.05.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 04/18/2019] [Accepted: 05/22/2019] [Indexed: 10/26/2022]
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7
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Gample SP, Agrawal S, Sarkar D. Evidence of nitrite acting as a stable and robust inducer of non-cultivability in Mycobacterium tuberculosis with physiological relevance. Sci Rep 2019; 9:9261. [PMID: 31239517 PMCID: PMC6593118 DOI: 10.1038/s41598-019-45652-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 05/30/2019] [Indexed: 11/21/2022] Open
Abstract
Tuberculosis (TB) is the ninth leading cause of death worldwide, ranking above human immunodeficiency virus. Latency is the major obstacle in the eradication of this disease. How the physiology of the pathogen changes in transition to the latent stage needs to be understood. The latent bacteria extracted from animal hosts exist in a nonculturable (NC) phase, whereas bacteria extracted from most in vitro models are culture-positive. In the present study, we observed that nitrite, up to a concentration of 5 mM, shows the growth of Mycobacterium tuberculosis (MTB) in liquid media, but this effect starts reversing at higher concentrations. At a concentration of 10 mM, nitrite induces rapid nonculturability of MTB at the aerobic stage. This noncultivable dormancy was confirmed by analyzing the characteristics of NC bacteria. Further differential gene expression analyses clearly supported the formation of a dormancy phenotype. This study will be helpful for the use of this bacillus as a dormancy model in future studies on TB latency.
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Affiliation(s)
- Suwarna P Gample
- CSIR-National Chemical Laboratory, Organic Chemistry Division, Pune, 411008, Maharashtra, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Sonia Agrawal
- CSIR-National Chemical Laboratory, Organic Chemistry Division, Pune, 411008, Maharashtra, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Dhiman Sarkar
- CSIR-National Chemical Laboratory, Organic Chemistry Division, Pune, 411008, Maharashtra, India. .,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India.
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8
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Song N, Li Z, Cui Z, Chen L, Cui Y, Dang G, Li Z, Li H, Liu S. The prominent alteration in transcriptome and metabolome of Mycobacterium bovis BCG str. Tokyo 172 induced by vitamin B 1. BMC Microbiol 2019; 19:104. [PMID: 31117936 PMCID: PMC6530141 DOI: 10.1186/s12866-019-1492-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 05/14/2019] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Vitamin B1 (VB1) is a crucial dietary nutrient and essential cofactor for several key enzymes in the regulation of cellular and metabolic processes, and more importantly in the activation of immune system. To date, the precise role of VB1 in Mycobacterium tuberculosis remains to be fully understood. RESULTS In this study, the transcriptional and metabolic profiles of VB1-treated Mycobacterium. bovis BCG were analyzed by RNA-sequencing and LC-MS (Liquid chromatography coupled to mass spectrometry). The selection of BCG strain was based on its common physiological features shared with M. tuberculosis. The results of cell growth assays demonstrated that VB1 inhibited the BCG growth rate in vitro. Transcriptomic analysis revealed that the expression levels of genes related to fatty acid metabolism, cholesterol metabolism, glycolipid catabolism, DNA replication, protein translation, cell division and cell wall formation were significantly downregulated in M. bovis BCG treated with VB1. In addition, the metabolomics LC-MS data indicated that most of the amino acids and adenosine diphosphate (ADP) were decreased in M. bovis BCG strain after VB1 treatment. CONCLUSIONS This study provides the molecular and metabolic bases to understand the impacts of VB1 on M.bovis BCG.
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Affiliation(s)
- Ningning Song
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Zhaoli Li
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Ziyin Cui
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Liping Chen
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Yingying Cui
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Guanghui Dang
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Zhe Li
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - He Li
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Siguo Liu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
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9
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Sharma S, Kumari P, Vashist A, Kumar C, Nandi M, Tyagi JS. Cognate sensor kinase-independent activation of Mycobacterium tuberculosis response regulator DevR (DosR) by acetyl phosphate: implications in anti-mycobacterial drug design. Mol Microbiol 2019; 111:1182-1194. [PMID: 30589958 DOI: 10.1111/mmi.14196] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/22/2018] [Indexed: 11/30/2022]
Abstract
The DevRS/DosT two-component system is essential for mycobacterial survival under hypoxia, a prevailing stress within granulomas. DevR (also known as DosR) is activated by an inducing stimulus, such as hypoxia, through conventional phosphorylation by its cognate sensor kinases, DevS (also known as DosS) and DosT. Here, we show that the DevR regulon is activated by acetyl phosphate under 'non-inducing' aerobic conditions when Mycobacterium tuberculosis devS and dosT double deletion strain is cultured on acetate. Overexpression of phosphotransacetylase caused a perturbation of the acetate kinase-phosphotransacetylase pathway, a decrease in the concentration of acetyl phosphate and dampened the aerobic induction response in acetate-grown bacteria. The operation of two pathways of DevR activation, one through sensor kinases and the other by acetyl phosphate, was established by an analysis of wild-type DevS and phosphorylation-defective DevSH395Q mutant strains under conditions partially mimicking a granulomatous-like environment of acetate and hypoxia. Our findings reveal that DevR can be phosphorylated in vivo by acetyl phosphate. Importantly, we demonstrate that acetyl phosphate-dependent phosphorylation can occur in the absence of DevR's cognate kinases. Based on our findings, we conclude that anti-mycobacterial therapy should be targeted to DevR itself and not to DevS/DosT kinases.
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Affiliation(s)
- Saurabh Sharma
- Department of Biotechnology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India
| | - Priyanka Kumari
- Department of Biotechnology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India.,Experimental Animal Facility, National JALMA Institute of Leprosy and other Mycobacterial Diseases, Tajganj, Agra, India
| | - Atul Vashist
- Department of Biotechnology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India
| | - Chanchal Kumar
- Department of Biotechnology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India
| | - Malobi Nandi
- Department of Biotechnology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India.,Amity Institute of Biotechnology, Amity University, Haryana, India
| | - Jaya Sivaswami Tyagi
- Department of Biotechnology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India
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Vitamin C: A Natural Inhibitor of Cell Wall Functions and Stress Response in Mycobacteria. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019. [PMID: 30637707 DOI: 10.1007/978-981-13-3065-0_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/19/2023]
Abstract
Tuberculosis, caused by Mycobacterium tuberculosis, has re-emerged as a threat to human race. Conventional antibiotic treatments are failing due to different stress response strategies adopted by bacterial pathogens. Since time immemorial, Vitamin C is known to protect against pathogens by boosting immunity in humans. Recently, Vitamin C has been shown to directly kill M. tuberculosis including multiple drug-resistant strains by generation of oxidative radicals through Fenton's reaction. Concurrently, it inhibits (p)ppGpp-mediated stringent response thus effectively shutting down long-term survival and persistence in mycobacteria. Here, we have discussed historical perspective and recent evidences on Vitamin C-mediated inhibition of several key pathways of M. tuberculosis such as (p)ppGpp synthesis and mycobacterial cell wall function. Several cell wall components including mycolic acids are critical for mycobacterial virulence. We observed downregulation of various mycolic acids in M. smegmatis upon treatment with Vitamin C, and data have been presented here. Vitamin C has been shown to inhibit the biofilm growth as well as disrupt the formed biofilm in mycobacteria. Additionally, Vitamin C role in cell-mediated and humoral immunity has been elucidated. Vitamin C is toxic at high concentration; therefore we have proposed the idea of derivatizing Vitamin C in order to lower the minimal inhibition concentration (MIC) necessary to target M. tuberculosis.
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11
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Pei Z, Wu K, Li Z, Li C, Zeng L, Li F, Pei N, Liu H, Zhang SL, Song YZ, Zhang X, Xu J, Fan XY, Wang J. Pharmacologic ascorbate as a pro-drug for hydrogen peroxide release to kill mycobacteria. Biomed Pharmacother 2018; 109:2119-2127. [PMID: 30551469 DOI: 10.1016/j.biopha.2018.11.078] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 11/12/2018] [Accepted: 11/19/2018] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND AND PURPOSE Tuberculosis is one of the most highly fatal diseases worldwide, and one-third of the world's population has been infected with Mycobacterium tuberculosis (M. tuberculosis). A previous study showed that M. tuberculosis was highly susceptible to being killed by ascorbate (i.e. vitamin C, VC), but the molecular mechanisms of the bactericidal activity of VC against M. tuberculosis are still not well understood. EXPERIMENTAL APPROACH We assayed the effects of VC as an anti-tuberculosis drug against mycobacteria (i.e. M. bovis BCG or M. tuberculosis H37Rv) in macrophages (i.e. RAW 264.7 cells). Relative global protein expression changes in 5 mM VC-treated and control samples of H37Rv were investigated by Tandem mass tag (TMT)-based quantitative proteomic analysis. qRT-PCR was also used to measure the differential expression of six intracellular stress response mycobacteria genes. KEY RESULTS Quantitative proteomic analysis showed that 11 peptide components including rip3, fdxA, Rv2028c, mtp, LH57_00670, hspX, pfkB, Rv1824, Rv1813c, LH57_08410 and Rv2030c were up-regulated and 17 peptide components were down-regulated in 5 mM VC-treated H37Rv compared with the control samples. qRT-PCR also verified that VC could induce the expression of six genes (hsp, fdxD, furA, devR, hspX, and dnaB) in BCG and H37Rv. We also found that exosomes from RAW 264.7 cells treated with pharmacologic VC could kill M. bovis BCG in vitro. CONCLUSION AND IMPLICATIONS Our results demonstrated that the bactericidal activity of VC against mycobacteria, as a pro-drug for hydrogen peroxide formation (H2O2), was dependent on reactive oxygen species production and the activated oxidative stress pathway, which suggested that pharmaceutical VC and exosomes from macrophages treated with VC could be used as potential anti-tuberculosis drugs.
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Affiliation(s)
- Zenglin Pei
- Scientific Research Center, Shanghai Public Health Clinical Center, Fudan University, Jinshan District, Shanghai, China
| | - Kang Wu
- Scientific Research Center, Shanghai Public Health Clinical Center, Fudan University, Jinshan District, Shanghai, China
| | - Zehuan Li
- Department of General Surgery, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Chaoqun Li
- Department of Infectious Diseases, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Ling Zeng
- Scientific Research Center, Shanghai Public Health Clinical Center, Fudan University, Jinshan District, Shanghai, China
| | - Feng Li
- Department of Respirology, Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Ning Pei
- TB Center, Shanghai Emerging and Re-emerging Infectious Disease Institute, Fudan University, Shanghai, China
| | - Hongmei Liu
- Scientific Research Center, Shanghai Public Health Clinical Center, Fudan University, Jinshan District, Shanghai, China
| | - Shu-Lin Zhang
- TB Center, Shanghai Emerging and Re-emerging Infectious Disease Institute, Fudan University, Shanghai, China; Department of Immunology and Microbiology, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Yan-Zheng Song
- TB Center, Shanghai Emerging and Re-emerging Infectious Disease Institute, Fudan University, Shanghai, China
| | - Xiaoyan Zhang
- Scientific Research Center, Shanghai Public Health Clinical Center, Fudan University, Jinshan District, Shanghai, China
| | - Jianqing Xu
- Scientific Research Center, Shanghai Public Health Clinical Center, Fudan University, Jinshan District, Shanghai, China
| | - Xiao-Yong Fan
- Scientific Research Center, Shanghai Public Health Clinical Center, Fudan University, Jinshan District, Shanghai, China; TB Center, Shanghai Emerging and Re-emerging Infectious Disease Institute, Fudan University, Shanghai, China.
| | - Jin Wang
- Scientific Research Center, Shanghai Public Health Clinical Center, Fudan University, Jinshan District, Shanghai, China.
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12
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Vashist A, Malhotra V, Sharma G, Tyagi JS, Clark-Curtiss JE. Interplay of PhoP and DevR response regulators defines expression of the dormancy regulon in virulent Mycobacterium tuberculosis. J Biol Chem 2018; 293:16413-16425. [PMID: 30181216 PMCID: PMC6200940 DOI: 10.1074/jbc.ra118.004331] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 08/15/2018] [Indexed: 11/06/2022] Open
Abstract
The DevR response regulator of Mycobacterium tuberculosis is an established regulator of the dormancy response in mycobacteria and can also be activated during aerobic growth conditions in avirulent strains, suggesting a complex regulatory system. Previously, we reported culture medium-specific aerobic induction of the DevR regulon genes in avirulent M. tuberculosis H37Ra that was absent in the virulent H37Rv strain. To understand the underlying basis of this differential response, we have investigated aerobic expression of the Rv3134c-devR-devS operon using M. tuberculosis H37Ra and H37Rv devR overexpression strains, designated as LIX48 and LIX50, respectively. Overexpression of DevR led to the up-regulation of a large number of DevR regulon genes in aerobic cultures of LIX48, but not in LIX50. To ascertain the involvement of PhoP response regulator, also known to co-regulate a subset of DevR regulon genes, we complemented the naturally occurring mutant phoPRa gene of LIX48 with the WT phoPRv gene. PhoPRv dampened the induced expression of the DevR regulon by >70-80%, implicating PhoP in the negative regulation of devR expression. Electrophoretic mobility shift assays confirmed phosphorylation-independent binding of PhoPRv to the Rv3134c promoter and further revealed that DevR and PhoPRv proteins exhibit differential DNA binding properties to the target DNA. Through co-incubations with DNA, ELISA, and protein complementation assays, we demonstrate that DevR forms a heterodimer with PhoPRv but not with the mutant PhoPRa protein. The study puts forward a new possible mechanism for coordinated expression of the dormancy regulon, having implications in growth adaptations critical for development of latency.
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Affiliation(s)
- Atul Vashist
- the Department of Biotechnology, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Vandana Malhotra
- the Center for Infectious Diseases and Vaccinology, Biodesign Institute, and
- From the Department of Biochemistry, Sri Venkateswara College, University of Delhi, New Delhi 110021, India
| | - Gunjan Sharma
- the Department of Biotechnology, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Jaya Sivaswami Tyagi
- the Department of Biotechnology, All India Institute of Medical Sciences, New Delhi 110029, India
| | - Josephine E Clark-Curtiss
- the Center for Infectious Diseases and Vaccinology, Biodesign Institute, and
- the School of Life Sciences, Arizona State University, Tempe, Arizona 85287, and
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13
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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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14
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Multifaceted remodeling by vitamin C boosts sensitivity of Mycobacterium tuberculosis subpopulations to combination treatment by anti-tubercular drugs. Redox Biol 2018; 15:452-466. [PMID: 29413958 PMCID: PMC5975079 DOI: 10.1016/j.redox.2017.12.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 12/28/2017] [Accepted: 12/30/2017] [Indexed: 12/03/2022] Open
Abstract
Bacterial dormancy is a major impediment to the eradication of tuberculosis (TB), because currently used drugs primarily target actively replicating bacteria. Therefore, decoding of the critical survival pathways in dormant tubercle bacilli is a research priority to formulate new approaches for killing these bacteria. Employing a network-based gene expression analysis approach, we demonstrate that redox active vitamin C (vit C) triggers a multifaceted and robust adaptation response in Mycobacterium tuberculosis (Mtb) involving ~ 67% of the genome. Vit C-adapted bacteria display well-described features of dormancy, including growth stasis and progression to a viable but non-culturable (VBNC) state, loss of acid-fastness and reduction in length, dissipation of reductive stress through triglyceride (TAG) accumulation, protective response to oxidative stress, and tolerance to first line TB drugs. VBNC bacteria are reactivatable upon removal of vit C and they recover drug susceptibility properties. Vit C synergizes with pyrazinamide, a unique TB drug with sterilizing activity, to kill dormant and replicating bacteria, negating any tolerance to rifampicin and isoniazid in combination treatment in both in-vitro and intracellular infection models. Finally, the vit C multi-stress redox models described here also offer a unique opportunity for concurrent screening of compounds/combinations active against heterogeneous subpopulations of Mtb. These findings suggest a novel strategy of vit C adjunctive therapy by modulating bacterial physiology for enhanced efficacy of combination chemotherapy with existing drugs, and also possible synergies to guide new therapeutic combinations towards accelerating TB treatment. Vitamin C induces dormancy and reversible VBNC state in M. tuberculosis. Dormancy is achieved through a well-coordinated multifaceted bacterial response. Vitamin C synergy with pyrazinamide negates bacterial tolerance to other TB drugs. Vitamin C adjunctive therapy is a potential strategy for shortening chemotherapy. Vitamin C-based models are novel screening platforms for new compounds/combinations.
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15
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Syal K, Bhardwaj N, Chatterji D. Vitamin C targets (p)ppGpp synthesis leading to stalling of long-term survival and biofilm formation in Mycobacterium smegmatis. FEMS Microbiol Lett 2016; 364:fnw282. [PMID: 27986825 DOI: 10.1093/femsle/fnw282] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Revised: 09/23/2016] [Accepted: 12/15/2016] [Indexed: 12/26/2022] Open
Abstract
Earlier, vitamin C was demonstrated to sterilize Mycobacterium tuberculosis culture via Fenton's reaction at high concentration. It alters the regulatory pathways associated with stress response and dormancy. Since (p)ppGpp is considered to be the master regulator of stress response and is responsible for bacterial survival under stress, we tested the effect of vitamin C on the formation of (p)ppGpp. In vivo estimation of (p)ppGpp showed a decrease in (p)ppGpp levels in vitamin C-treated M. smegmatis cells in comparison to the untreated cells. Furthermore, in vitro (p)ppGpp synthesis using RelMSM enzyme was conducted in order to confirm the specificity of the inhibition in the presence of variable concentrations of vitamin C. We observed that vitamin C at high concentration can inhibit the synthesis of (p)ppGpp. We illustrated binding of vitamin C to RelMSM by isothermal titration calorimetry. Enzyme kinetics was followed where K0.5 was found to be increased with the concomitant reduction of Vmax value suggesting mixed inhibition. Both long-term survival and biofilm formation were inhibited by vitamin C. The experiments suggest that vitamin C has the potential to be developed as the inhibitor of (p)ppGpp synthesis and stress response, at least in the concentration range used here.
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Affiliation(s)
- Kirtimaan Syal
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560012, India
| | - Neerupma Bhardwaj
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560012, India
| | - Dipankar Chatterji
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560012, India
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16
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Coppola M, van Meijgaarden KE, Franken KLMC, Commandeur S, Dolganov G, Kramnik I, Schoolnik GK, Comas I, Lund O, Prins C, van den Eeden SJF, Korsvold GE, Oftung F, Geluk A, Ottenhoff THM. New Genome-Wide Algorithm Identifies Novel In-Vivo Expressed Mycobacterium Tuberculosis Antigens Inducing Human T-Cell Responses with Classical and Unconventional Cytokine Profiles. Sci Rep 2016; 6:37793. [PMID: 27892960 PMCID: PMC5125271 DOI: 10.1038/srep37793] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 11/03/2016] [Indexed: 12/16/2022] Open
Abstract
New strategies are needed to develop better tools to control TB, including identification of novel antigens for vaccination. Such Mtb antigens must be expressed during Mtb infection in the major target organ, the lung, and must be capable of eliciting human immune responses. Using genome-wide transcriptomics of Mtb infected lungs we developed data sets and methods to identify IVE-TB (in-vivo expressed Mtb) antigens expressed in the lung. Quantitative expression analysis of 2,068 Mtb genes from the predicted first operons identified the most upregulated IVE-TB genes during in-vivo pulmonary infection. By further analysing high-level conservation among whole-genome sequenced Mtb-complex strains (n = 219) and algorithms predicting HLA-class-Ia and II presented epitopes, we selected the most promising IVE-TB candidate antigens. Several of these were recognized by T-cells from in-vitro Mtb-PPD and ESAT6/CFP10-positive donors by proliferation and multi-cytokine production. This was validated in an independent cohort of latently Mtb-infected individuals. Significant T-cell responses were observed in the absence of IFN-γ-production. Collectively, the results underscore the power of our novel antigen discovery approach in identifying Mtb antigens, including those that induce unconventional T-cell responses, which may provide important novel tools for TB vaccination and biomarker profiling. Our generic approach is applicable to other infectious diseases.
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Affiliation(s)
- Mariateresa Coppola
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Kees L M C Franken
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - Susanna Commandeur
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - Gregory Dolganov
- Department Microbiology Immunology, Stanford Univ. School of Medicine, Stanford, USA
| | - Igor Kramnik
- Department Immunology Infectious Diseases, Harvard School of Public Health, Boston, USA
| | - Gary K Schoolnik
- Department Microbiology Immunology, Stanford Univ. School of Medicine, Stanford, USA
| | - Inaki Comas
- Institute of Biomedicine of Valencia (IBV-CSIC), Valencia, Spain.,CIBER in Epidemiology and Public Health, Madrid, Spain
| | - Ole Lund
- Dept. Systems Biology, Technical Univ., Denmark
| | - Corine Prins
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - Susan J F van den Eeden
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - Gro E Korsvold
- Department of Infectious Disease Immunology, Domain for Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Fredrik Oftung
- Department of Infectious Disease Immunology, Domain for Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Annemieke Geluk
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - Tom H M Ottenhoff
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
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17
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Kirtania P, Ghosh S, Bhawsinghka N, Chakladar M, Das Gupta SK. Vitamin C induced DevR-dependent synchronization of Mycobacterium smegmatis growth and its effect on the proliferation of mycobacteriophage D29. FEMS Microbiol Lett 2016; 363:fnw097. [PMID: 27190284 DOI: 10.1093/femsle/fnw097] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/12/2016] [Indexed: 01/18/2023] Open
Abstract
Vitamin C is known to inhibit mycobacterial growth by acting as a hypoxia inducing agent. While investigating how mycobacteriophage growth is influenced by hypoxic conditions induced by vitamin C, using Mycobacterium smegmatis- mycobacteriophage D29 as a model system, it was observed that prior exposure of the host to such conditions resulted in increased burst size of the phage. Vitamin C pre-exposure was also found to induce synchronous growth of the host. A mutant defective in DevR, the response regulator that controls hypoxic responses in mycobacteria, neither supported higher phage bursts nor was it able to undergo synchronized growth following vitamin C pre-exposure, indicating thereby that the two phenomena are interrelated. Further evidence supporting such an interrelationship was obtained from the observation that phage burst sizes varied depending on the stage of synchronous growth that the host cells were in, at the time of infection-higher bursts were observed in the resting/synthetic phases and lower in the dividing ones. The effects were specific in nature as synchronization by an unrelated method, known as 'crowding', did not lead to the same consequence. The results indicate that growth synchronization induced by vitamin C treatment is a DevR-dependent phenomenon which is exploited by mycobacteriophage D29 to grow in larger numbers.
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Affiliation(s)
- Prithwiraj Kirtania
- Bose Institute, Department Of Microbiology, P1/12 C.I.T. Scheme VIIM, Kolkata 700054, India
| | - Shreya Ghosh
- Bose Institute, Department Of Microbiology, P1/12 C.I.T. Scheme VIIM, Kolkata 700054, India
| | - Niketa Bhawsinghka
- Bose Institute, Department Of Microbiology, P1/12 C.I.T. Scheme VIIM, Kolkata 700054, India
| | - Madhumita Chakladar
- Bose Institute, Department Of Microbiology, P1/12 C.I.T. Scheme VIIM, Kolkata 700054, India
| | - Sujoy K Das Gupta
- Bose Institute, Department Of Microbiology, P1/12 C.I.T. Scheme VIIM, Kolkata 700054, India
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18
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Song N, Cui Y, Li Z, Chen L, Liu S. New Targets and Cofactors for the Transcription Factor LrpA fromMycobacterium tuberculosis. DNA Cell Biol 2016; 35:167-76. [DOI: 10.1089/dna.2015.3040] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Affiliation(s)
- Ningning Song
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Yingying Cui
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, China
| | - Zhaoli Li
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Liping Chen
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
| | - Siguo Liu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, China
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