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Kalyan M, Sharma S, Kaur P, Sharma A, Verma I. Antibody response to mycobacterial Rpf B protein and its immunodominant peptides in HIV-TB co-infected individuals. Tuberculosis (Edinb) 2024; 144:102464. [PMID: 38141523 DOI: 10.1016/j.tube.2023.102464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Revised: 12/10/2023] [Accepted: 12/11/2023] [Indexed: 12/25/2023]
Abstract
Diagnosis of TB at early stages of HIV infection may lead to timely intervention for improving patient outcome. Antibodies to Mycobacterium tuberculosis recombinant RpfB protein and two immunodominant peptides of Rpf B protein were evaluated in the sera of HIV +TB+, HIV+ and HIV- pulmonary TB patients by ELISA. Serum antibodies from 90 % and 65 % of HIV+TB+ patients reacted to recombinant RpfB protein and synthetic peptide RpfP1 respectively. Overall, this study shows that resuscitation promoting factor B elicits humoral antibody response in HIV+TB+ co-infected individuals and be proposed as a potential biomarker for diagnosis of HIV+TB+ patients, however further longitudinal follow up studies are warranted.
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Affiliation(s)
- Madhur Kalyan
- Department of Biochemistry, Post Graduate Institute of Medical Education and Research, Chandigarh, 160012, India.
| | - Sumedha Sharma
- Department of Biochemistry, Post Graduate Institute of Medical Education and Research, Chandigarh, 160012, India.
| | - Prabhdeep Kaur
- Department of Biochemistry, Post Graduate Institute of Medical Education and Research, Chandigarh, 160012, India.
| | - Aman Sharma
- Department of Internal Medicine, Post Graduate Institute of Medical Education and Research, Chandigarh, 160012, India.
| | - Indu Verma
- Department of Biochemistry, Post Graduate Institute of Medical Education and Research, Chandigarh, 160012, India.
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Du F, Xing A, Li Z, Pan L, Jia H, Du B, Sun Q, Wei R, Liu Z, Zhang Z. Rapid Detection of Mycobacterium tuberculosis in Pleural Fluid Using Resuscitation-Promoting Factor-Based Thin Layer Agar Culture Method. Front Microbiol 2022; 13:803521. [PMID: 35250926 PMCID: PMC8888910 DOI: 10.3389/fmicb.2022.803521] [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: 10/28/2021] [Accepted: 01/10/2022] [Indexed: 11/21/2022] Open
Abstract
Background Pleural tuberculous is difficult to diagnose. Culture is still considered the gold standard, especially in resource-limited settings where quick, cheap, and easy techniques are needed. The aim of the study was to evaluate resuscitation-promoting factors (Rpfs)-based thin layer agar (TLA) culture method for quick detection of Mycobacterium tuberculosis in pleural fluid. Methods Patients with suspected pleural TB were enrolled prospectively in our hospital, pleural fluid of all patients were collected, stained with Ziehl–Neelsen for acid-fast bacilli (AFB), cultured on Rpfs-TLA, TLA, and Löwenstein–Jensen (LJ) medium, and identified according to recommended procedures. Results A total of 137 suspected pleural TB were enrolled and categorized, including 103 pleural TB (49 confirmed and 54 probable pleural TB) and 34 non-TBP patients. The sensitivity of Rpfs-TLA for total pleural TB was 43.7% (34.5∼53.3%), higher than that of TLA 29.1% (21.2∼38.5%) and LJ 26.2% (18.7∼35.5%) (p < 0.01), and all specificity was 100% in the diagnosis of pleural TB. Median time to detection of a positive culture was 11.8 days (95% CI 10.4∼13.4) for Rpfs-TLA, 21.0 days (95% CI 19.1∼22.9) for TLA, and 30.5 days (95% CI 28.5∼32.5) for LJ (p < 0.001). Conclusion Rpfs-TLA is an accurate, rapid, cheap, and easy culture method, which makes it promising for use in clinical laboratories.
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Affiliation(s)
- Fengjiao Du
- Beijing Key Laboratory of Drug Resistance Tuberculosis Research, Beijing Chest Hospital, Beijing Tuberculosis and Thoracic Tumor Research Institute, Capital Medical University, Beijing, China
| | - Aiying Xing
- Beijing Key Laboratory of Drug Resistance Tuberculosis Research, Beijing Chest Hospital, Beijing Tuberculosis and Thoracic Tumor Research Institute, Capital Medical University, Beijing, China
| | - Zihui Li
- Beijing Key Laboratory of Drug Resistance Tuberculosis Research, Beijing Chest Hospital, Beijing Tuberculosis and Thoracic Tumor Research Institute, Capital Medical University, Beijing, China
| | - Liping Pan
- Beijing Key Laboratory of Drug Resistance Tuberculosis Research, Beijing Chest Hospital, Beijing Tuberculosis and Thoracic Tumor Research Institute, Capital Medical University, Beijing, China
| | - Hongyan Jia
- Beijing Key Laboratory of Drug Resistance Tuberculosis Research, Beijing Chest Hospital, Beijing Tuberculosis and Thoracic Tumor Research Institute, Capital Medical University, Beijing, China
| | - Boping Du
- Beijing Key Laboratory of Drug Resistance Tuberculosis Research, Beijing Chest Hospital, Beijing Tuberculosis and Thoracic Tumor Research Institute, Capital Medical University, Beijing, China
| | - Qi Sun
- Beijing Key Laboratory of Drug Resistance Tuberculosis Research, Beijing Chest Hospital, Beijing Tuberculosis and Thoracic Tumor Research Institute, Capital Medical University, Beijing, China
| | - Rongrong Wei
- Beijing Key Laboratory of Drug Resistance Tuberculosis Research, Beijing Chest Hospital, Beijing Tuberculosis and Thoracic Tumor Research Institute, Capital Medical University, Beijing, China
| | - Zhongquan Liu
- Beijing Key Laboratory of Drug Resistance Tuberculosis Research, Beijing Chest Hospital, Beijing Tuberculosis and Thoracic Tumor Research Institute, Capital Medical University, Beijing, China
| | - Zongde Zhang
- Beijing Key Laboratory of Drug Resistance Tuberculosis Research, Beijing Chest Hospital, Beijing Tuberculosis and Thoracic Tumor Research Institute, Capital Medical University, Beijing, China
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McIvor A, Gordhan BG, Waja Z, Otwombe K, Martinson NA, Kana BD. Supplementation of sputum cultures with culture filtrate to detect tuberculosis in a cross-sectional study of HIV-infected individuals. Tuberculosis (Edinb) 2021; 129:102103. [PMID: 34144375 DOI: 10.1016/j.tube.2021.102103] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 03/02/2021] [Accepted: 06/09/2021] [Indexed: 10/21/2022]
Abstract
While some healthcare systems have shifted to molecular diagnostics, culture still remains the gold standard for tuberculosis diagnosis, but it is limited by its long duration to a positive result. Methods to reduce time to culture positivity (TTP) are urgently required. We determined if growth factor supplementation in the mycobacterial growth indicator tube (MGIT) culture system reduces TTP. MGITs were supplemented with fresh culture filtrate (CF) as a source of growth stimulatory molecules from axenic Mycobacterium tuberculosis culture. Different volumes of CF and media components were tested. The performance of these modified MGITs was assessed with sputum from HIV-TB co-infected individuals. Reducing the volume of MGIT cultures and removal of detergent from cultures grown to generate CF had a marginal but significant benefit on reducing TTP. In a subset of specimens, CF inhibited growth. Following optimization of methods, a reduced TTP occurred in specimens with low bacillary load as measured by GeneXpert, smear microscopy and colony forming units. Three specimens that were negative under standard conditions flagged positive following CF supplementation. Our data provide preliminary evidence that addition of CF to MGIT cultures can enhance detection of M. tuberculosis in HIV-TB co-infected patients with low sputum bacillary loads.
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Affiliation(s)
- Amanda McIvor
- DST/NRF Centre of Excellence for Biomedical TB Research, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and the National Health Laboratory Service, South Africa
| | - Bhavna Gowan Gordhan
- DST/NRF Centre of Excellence for Biomedical TB Research, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and the National Health Laboratory Service, South Africa
| | - Ziyaad Waja
- Perinatal HIV Research Unit (PHRU), University of the Witwatersrand, Johannesburg, South Africa
| | - Kennedy Otwombe
- Perinatal HIV Research Unit (PHRU), University of the Witwatersrand, Johannesburg, South Africa; School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, South Africa
| | - Neil A Martinson
- DST/NRF Centre of Excellence for Biomedical TB Research, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and the National Health Laboratory Service, South Africa; Perinatal HIV Research Unit (PHRU), University of the Witwatersrand, Johannesburg, South Africa; John Hopkins University, Centre for Tuberculosis Research, Baltimore, MD, USA
| | - Bavesh Davandra Kana
- DST/NRF Centre of Excellence for Biomedical TB Research, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand and the National Health Laboratory Service, South Africa; CAPRISA, Centre for the AIDS Programme of Research in South Africa, Durban, South Africa.
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Animal Models of Tuberculosis Vaccine Research: An Important Component in the Fight against Tuberculosis. BIOMED RESEARCH INTERNATIONAL 2020; 2020:4263079. [PMID: 32025519 PMCID: PMC6984742 DOI: 10.1155/2020/4263079] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 07/25/2019] [Accepted: 08/20/2019] [Indexed: 12/23/2022]
Abstract
Tuberculosis (TB), an infectious disease caused by Mycobacterium tuberculosis, is one of the top ten infectious diseases worldwide, and is the leading cause of morbidity from a single infectious agent. M. tuberculosis can cause infection in several species of animals in addition to humans as the natural hosts. Although animal models of TB disease cannot completely simulate the occurrence and development of human TB, they play an important role in studying the pathogenesis, immune responses, and pathological changes as well as for vaccine research. This review summarizes the commonly employed animal models, including mouse, guinea pig, rabbit, rat, goat, cattle, and nonhuman primates, and their characteristics as used in TB vaccine research, and provides a basis for selecting appropriate animal models according to specific research needs. Furthermore, some of the newest animal models used for TB vaccine research (such as humanized animal models, zebrafish, Drosophila, and amoeba) are introduced, and their characteristics and research progress are discussed.
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Dusthackeer A, Balasubramanian M, Shanmugam G, Priya S, Nirmal CR, Sam Ebenezer R, Balasubramanian A, Mondal RK, Thiruvenkadam K, Hemanth Kumar AK, Ramachandran G, Subbian S. Differential Culturability of Mycobacterium tuberculosis in Culture-Negative Sputum of Patients With Pulmonary Tuberculosis and in a Simulated Model of Dormancy. Front Microbiol 2019; 10:2381. [PMID: 31749768 PMCID: PMC6842972 DOI: 10.3389/fmicb.2019.02381] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 10/01/2019] [Indexed: 02/03/2023] Open
Abstract
Tuberculosis (TB) remains a leading killer among infectious diseases of humans worldwide. Delayed diagnosis is a crucial problem in global TB control programs. Bacteriological methods currently used to diagnose TB in endemic countries take up to 8 weeks, which poses a significant delay in starting antibiotic therapy. The presence of a heterogeneous population of Mycobacterium tuberculosis, the causative agent of TB, is among the reasons for delayed diagnosis by bacteriological methods. Previously, it has been shown that mycobacterial resuscitation-promoting factors (RPFs), a family of proteins secreted by actively growing bacteria into the media, are capable of activating the growth of dormant bacteria, thus enhancing the detection of bacilli in the sputum of confirmed TB cases. However, the variability in bacterial resuscitation by RPF in the sputum of suspected pulmonary TB cases that showed differential smear and/or culture positivity during diagnosis has not been fully explored. Here, we report the presence of non-replicating bacteria in the sputum of suspected TB cases that show differential growth response to RPF treatment. Using crude and recombinant RPF treatment, we show improved sensitivity and reduced time to detect bacilli in the sputum samples of smear-positive/culture-negative or smear-negative/culture-negative cases. We also report the phenotypic heterogeneity in the RPF responsiveness among Mtb strains using an in vitro dormancy model. Our findings have implications for improving the bacteriological diagnostic modalities currently used to diagnose TB in endemic countries.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Selvakumar Subbian
- Public Health Research Institute, New Jersey Medical School, Rutgers University, Newark, NJ, United States
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Squeglia F, Moreira M, Ruggiero A, Berisio R. The Cell Wall Hydrolytic NlpC/P60 Endopeptidases in Mycobacterial Cytokinesis: A Structural Perspective. Cells 2019; 8:cells8060609. [PMID: 31216697 PMCID: PMC6628586 DOI: 10.3390/cells8060609] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 06/12/2019] [Accepted: 06/14/2019] [Indexed: 12/11/2022] Open
Abstract
In preparation for division, bacteria replicate their DNA and segregate the newly formed chromosomes. A division septum then assembles between the chromosomes, and the mother cell splits into two identical daughters due to septum degradation. A major constituent of bacterial septa and of the whole cell wall is peptidoglycan (PGN), an essential cell wall polymer, formed by glycan chains of β−(1-4)-linked-N-acetylglucosamine (GlcNAc) and N-acetylmuramic acid (MurNAc), cross-linked by short peptide stems. Depending on the amino acid located at the third position of the peptide stem, PGN is classified as either Lys-type or meso-diaminopimelic acid (DAP)-type. Hydrolytic enzymes play a crucial role in the degradation of bacterial septa to split the cell wall material shared by adjacent daughter cells to promote their separation. In mycobacteria, a key PGN hydrolase, belonging to the NlpC/P60 endopeptidase family and denoted as RipA, is responsible for the degradation of septa, as the deletion of the gene encoding for this enzyme generates abnormal bacteria with multiple septa. This review provides an update of structural and functional data highlighting the central role of RipA in mycobacterial cytokinesis and the fine regulation of its catalytic activity, which involves multiple molecular partners.
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Affiliation(s)
- Flavia Squeglia
- Institute of Biostructures and Bioimaging (IBB), CNR, 80134 Naples, Italy.
| | - Miguel Moreira
- Institute of Biostructures and Bioimaging (IBB), CNR, 80134 Naples, Italy.
| | - Alessia Ruggiero
- Institute of Biostructures and Bioimaging (IBB), CNR, 80134 Naples, Italy.
| | - Rita Berisio
- Institute of Biostructures and Bioimaging (IBB), CNR, 80134 Naples, Italy.
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Liang Y, Zhao Y, Bai X, Xiao L, Yang Y, Zhang J, Wang L, Cui L, Wang T, Shi Y, Zhao W, Wu X. Immunotherapeutic effects of Mycobacterium tuberculosis rv3407 DNA vaccine in mice. Autoimmunity 2019; 51:417-422. [PMID: 30632804 DOI: 10.1080/08916934.2018.1546291] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Tuberculosis (TB) is a major global public health problem. Latent TB infection (LTBI) is a major source of active TB. New vaccines to treat LTBI are urgently demanded. In this study, the gene encoding latency-associated antigen Rv3407 of Mycobacterium tuberculosis (MTB) rv3407 DNA vaccine was used to prepare and the immunogenicity and therapeutic effects were evaluated. Normal mice were immunized intramuscularly three times at two-week intervals with sterile water for injection, plasmid vector pVAX1, M. vaccae vaccine, ag85a DNA or rv3407 DNA. TB-infected mice were immunized intramuscularly three times at two-week intervals with phosphate-buffered saline (PBS) and rv3407 DNA. The normal mice immunized with rv3407 DNA or ag85a DNA showed higher levels of interferon-gamma (IFN-γ) in stimulated spleen lymphocyte culture supernatants, and had more Th1 cells and an elevated ratio of Th1/Th2 immune cells in whole blood, indicating that a Th1-type immune response was predominant. The levels of anti-Ag85A or anti-Rv3407 IgG antibody were significantly increased in the ag85a DNA and rv3407 DNA groups compared to the sterile water for injection, vector, and M. vaccae groups (p < .0001). Compared with the PBS group, the rv3407 DNA group had pulmonary bacterial loads that were lower by 0.56 log10 (p < .01). The mice vaccinated with rv3407 DNA developed antigen-specific cellular and humoral responses. The rv3407 DNA is a potential DNA vaccine candidate against TB.
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Affiliation(s)
- Yan Liang
- a Army Tuberculosis Prevention and Control Key Laboratory , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China.,b Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China
| | - Yajing Zhao
- a Army Tuberculosis Prevention and Control Key Laboratory , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China.,b Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China.,c Respiratory Department , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China
| | - Xuejuan Bai
- a Army Tuberculosis Prevention and Control Key Laboratory , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China.,b Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China
| | - Li Xiao
- a Army Tuberculosis Prevention and Control Key Laboratory , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China.,b Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China
| | - Yourong Yang
- a Army Tuberculosis Prevention and Control Key Laboratory , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China.,b Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China
| | - Junxian Zhang
- a Army Tuberculosis Prevention and Control Key Laboratory , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China.,b Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China
| | - Lan Wang
- a Army Tuberculosis Prevention and Control Key Laboratory , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China.,b Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China
| | - Lei Cui
- a Army Tuberculosis Prevention and Control Key Laboratory , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China.,b Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China
| | - Tong Wang
- a Army Tuberculosis Prevention and Control Key Laboratory , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China.,b Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China
| | - Yingchang Shi
- a Army Tuberculosis Prevention and Control Key Laboratory , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China.,b Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China
| | - Weiguo Zhao
- c Respiratory Department , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China
| | - Xueqiong Wu
- a Army Tuberculosis Prevention and Control Key Laboratory , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China.,b Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research , The 8th Medical Center of PLA General Hospital , Beijing , P. R. China
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Resuscitation-Promoting Factors Are Required for Mycobacterium smegmatis Biofilm Formation. Appl Environ Microbiol 2018; 84:AEM.00687-18. [PMID: 29915116 DOI: 10.1128/aem.00687-18] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 06/10/2018] [Indexed: 12/19/2022] Open
Abstract
Resuscitation-promoting factors (Rpfs) have previously been shown to act as growth-stimulatory molecules via their lysozyme-like activity on peptidoglycan in the bacterial cell wall. In this study, we investigated the ability of Mycobacterium smegmatis strains lacking rpf genes to form biofilms and tested their susceptibilities to cell wall-targeting agents. M. smegmatis contains four distinct rpf homologues, namely, MSMEG_5700 (rpfA), MSMEG_5439 (rpfB), MSMEG_4640 (rpfE2), and MSMEG_4643 (rpfE). During axenic growth of the wild-type strain, all four mRNA transcripts were expressed to various degrees, but the expression of MSMEG_4643 was significantly greater during exponential growth. Similarly, all rpf mRNA transcripts could be detected in biofilms grown for 7, 14, and 28 days, with MSMEG_4643 expressed at the highest abundance after 7 days. In-frame unmarked deletion mutants (single and combinatorial) were generated and displayed altered colony morphologies and the inability to form typical biofilms. Moreover, any strain lacking rpfA and rpfB simultaneously exhibited increased susceptibility to rifampin, vancomycin, and SDS. Exogenous Rpf supplementation in the form of culture filtrate failed to restore biofilm formation. Liquid chromatography-mass spectrometry (LC-MS) analysis of peptidoglycan (PG) suggested a reduction in 4-3 cross-linked PG in the ΔrpfABEE2 mutant strain. In addition, the level of PG-repeat units terminating in 1,6-anhydroMurNAc appeared to be significantly reduced in the quadruple rpf mutant. Collectively, our data have shown that Rpfs play an important role in biofilm formation, possibly through alterations in PG cross-linking and the production of signaling molecules.IMPORTANCE The cell wall of pathogenic mycobacteria is composed of peptidoglycan, arabinogalactan, mycolic acids, and an outer capsule. This inherent complexity renders it resistant to many antibiotics. Consequently, its biosynthesis and remodeling during growth directly impact viability. Resuscitation-promoting factors (Rpfs), enzymes with lytic transglycosylase activity, have been associated with the revival of dormant cells and subsequent resumption of vegetative growth. Mycobacterium smegmatis, a soil saprophyte and close relative of the human pathogen Mycobacterium tuberculosis, encodes four distinct Rpfs. Herein, we assessed the relationship between Rpfs and biofilm formation, which is used as a model to study drug tolerance and bacterial signaling in mycobacteria. We demonstrated that progressive deletion of rpf genes hampered the development of biofilms and reduced drug tolerance. These effects were accompanied by a reduction in muropeptide production and altered peptidoglycan cross-linking. Collectively, these observations point to an important role for Rpfs in mycobacterial communication and drug tolerance.
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Gong W, Liang Y, Wu X. The current status, challenges, and future developments of new tuberculosis vaccines. Hum Vaccin Immunother 2018; 14:1697-1716. [PMID: 29601253 DOI: 10.1080/21645515.2018.1458806] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Mycobacterium tuberculosis complex causes tuberculosis (TB), one of the top 10 causes of death worldwide. TB results in more fatalities than multi-drug resistant (MDR) HIV strain related coinfection. Vaccines play a key role in the prevention and control of infectious diseases. Unfortunately, the only licensed preventive vaccine against TB, bacilli Calmette-Guérin (BCG), is ineffective for prevention of pulmonary TB in adults. Therefore, it is very important to develop novel vaccines for TB prevention and control. This literature review provides an overview of the innate and adaptive immune response during M. tuberculosis infection, and presents current developments and challenges to novel TB vaccines. A comprehensive understanding of vaccines in preclinical and clinical studies provides extensive insight for the development of safer and more efficient vaccines, and may inspire new ideas for TB prevention and treatment.
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Affiliation(s)
- Wenping Gong
- a Army Tuberculosis Prevention and Control Key Laboratory/Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute for Tuberculosis Research , Haidian District, Beijing , China
| | - Yan Liang
- a Army Tuberculosis Prevention and Control Key Laboratory/Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute for Tuberculosis Research , Haidian District, Beijing , China
| | - Xueqiong Wu
- a Army Tuberculosis Prevention and Control Key Laboratory/Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute for Tuberculosis Research , Haidian District, Beijing , China
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Liang Y, Zhang X, Bai X, Xiao L, Wang X, Zhang J, Yang Y, Song J, Wang L, Wu X. Immunogenicity and therapeutic effects of a Mycobacterium tuberculosis rv2190c DNA vaccine in mice. BMC Immunol 2017; 18:11. [PMID: 28241799 PMCID: PMC5327546 DOI: 10.1186/s12865-017-0196-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2016] [Accepted: 02/16/2017] [Indexed: 11/14/2022] Open
Abstract
Background Tuberculosis (TB) is a major global public health problem. New treatment methods on TB are urgently demanded. In this study, Mycobacterium tuberculosis (MTB) rv2190c DNA vaccine was prepared and its immunogenicity and therapeutic effects were evaluated. Results Non-infected mice immunized with rv2190c DNA or ag85a DNA showed higher levels of interferon-gamma (IFN-γ) in stimulated spleen lymphocyte culture supernatants, and had more Th1 cells and an elevatory ratio of Th1/Th2 immune cells in whole blood, indicating that Th1-type immune response was predominant. Compared with the saline group, ag85a DNA group and rv2190c DNA group in the infected mice decreased the lung colony-forming units (CFUs) by 0.533 and 0.283 log10, and spleen CFUs by 0.425 and 0.321 log10 respectively, and pathological lesion. Conclusions The rv2190c DNA had some immunotherapeutic effect on TB. Electronic supplementary material The online version of this article (doi:10.1186/s12865-017-0196-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yan Liang
- Army Tuberculosis Prevention and Control Key Laboratory, Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research, the 309th Hospital of Chinese PLA, Beijing, 100091, People's Republic of China
| | - Xiaoyan Zhang
- Army Tuberculosis Prevention and Control Key Laboratory, Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research, the 309th Hospital of Chinese PLA, Beijing, 100091, People's Republic of China.,Zhengzhou Kingmed Center for Clinical Laboratory, Zhengzhou, 450016, People's Republic of China
| | - Xuejuan Bai
- Army Tuberculosis Prevention and Control Key Laboratory, Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research, the 309th Hospital of Chinese PLA, Beijing, 100091, People's Republic of China
| | - Li Xiao
- Army Tuberculosis Prevention and Control Key Laboratory, Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research, the 309th Hospital of Chinese PLA, Beijing, 100091, People's Republic of China
| | - Xiaomei Wang
- Army Tuberculosis Prevention and Control Key Laboratory, Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research, the 309th Hospital of Chinese PLA, Beijing, 100091, People's Republic of China
| | - Junxian Zhang
- Army Tuberculosis Prevention and Control Key Laboratory, Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research, the 309th Hospital of Chinese PLA, Beijing, 100091, People's Republic of China
| | - Yourong Yang
- Army Tuberculosis Prevention and Control Key Laboratory, Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research, the 309th Hospital of Chinese PLA, Beijing, 100091, People's Republic of China
| | - Jinying Song
- Army Tuberculosis Prevention and Control Key Laboratory, Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research, the 309th Hospital of Chinese PLA, Beijing, 100091, People's Republic of China
| | - Lan Wang
- Army Tuberculosis Prevention and Control Key Laboratory, Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research, the 309th Hospital of Chinese PLA, Beijing, 100091, People's Republic of China
| | - Xueqiong Wu
- Army Tuberculosis Prevention and Control Key Laboratory, Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute of Tuberculosis Research, the 309th Hospital of Chinese PLA, Beijing, 100091, People's Republic of China.
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Rosser A, Stover C, Pareek M, Mukamolova GV. Resuscitation-promoting factors are important determinants of the pathophysiology in Mycobacterium tuberculosis infection. Crit Rev Microbiol 2017; 43:621-630. [PMID: 28338360 DOI: 10.1080/1040841x.2017.1283485] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Resuscitation promoting factors (Rpf) are peptidoglycan-hydrolyzing enzymes that are pivotal in the resuscitation of quiescent actinobacteria including Mycobacterium tuberculosis. From the published data, it is clear that Rpf are required for the resuscitation of non-replicating bacilli and pathogenesis in murine infection model of tuberculosis, although their direct influence on human Mycobacterium tuberculosis infection is ill-defined. In this review, we describe the progress in the understanding of the roles that Rpf play in human tuberculosis pathogenesis and importance of bacilli dependent upon Rpf for growth for the outcome of human tuberculosis. We outline how this research is opening up important opportunities for the diagnosis, treatment and prevention of human disease, progress in which is essential to attain the ultimate goal of tuberculosis eradication.
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Affiliation(s)
- Andrew Rosser
- a Department of Infection, Immunity and Inflammation , University of Leicester , Leicester , UK.,b Department of Infection and Tropical Medicine , University Hospitals of Leicester NHS Trust , Leicester , UK
| | - Cordula Stover
- a Department of Infection, Immunity and Inflammation , University of Leicester , Leicester , UK
| | - Manish Pareek
- a Department of Infection, Immunity and Inflammation , University of Leicester , Leicester , UK.,b Department of Infection and Tropical Medicine , University Hospitals of Leicester NHS Trust , Leicester , UK
| | - Galina V Mukamolova
- a Department of Infection, Immunity and Inflammation , University of Leicester , Leicester , UK
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van Wyk N, Drancourt M, Henrissat B, Kremer L. Current perspectives on the families of glycoside hydrolases ofMycobacterium tuberculosis: their importance and prospects for assigning function to unknowns. Glycobiology 2016; 27:112-122. [DOI: 10.1093/glycob/cww099] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 08/28/2016] [Accepted: 09/26/2016] [Indexed: 11/14/2022] Open
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Ruggiero A, Squeglia F, Romano M, Vitagliano L, De Simone A, Berisio R. The structure of Resuscitation promoting factor B from M. tuberculosis reveals unexpected ubiquitin-like domains. Biochim Biophys Acta Gen Subj 2015; 1860:445-51. [PMID: 26549874 DOI: 10.1016/j.bbagen.2015.11.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 10/26/2015] [Accepted: 11/02/2015] [Indexed: 10/22/2022]
Abstract
BACKGROUND RpfB is a key factor in resuscitation from dormancy of Mycobacterium tuberculosis. This protein is a cell-wall glycosidase, which cleaves cell-wall peptidoglycan. RpfB is structurally complex and is composed of three types of domains, including a catalytic, a G5 and three DUF348 domains. Structural information is currently limited to a portion of the protein including only the catalytic and G5 domains. To gain insights into the structure and function of all domains we have undertaken structural investigations on a large protein fragment containing all three types of domains that constitute RpfB (RpfB3D). METHODS The structural features of RpfB3D have been investigated combining x-ray crystallography and biophysical studies. RESULTS AND CONCLUSIONS The crystal structure of RpfB3D provides the first structural characterization of a DUF348 domain and revealed an unexpected structural relationship with ubiquitin. The crystal structure also provides specific structural features of these domains explaining their frequent association with G5 domains. GENERAL SIGNIFICANCE Results provided novel insights into the mechanism of peptidoglycan degradation necessary to the resuscitation of M. tuberculosis. Features of the DUF348 domain add structural data to a large set of proteins embedding this domain. Based on its structural similarity to ubiquitin and frequent association to the G5 domain, we propose to name this domain as G5-linked-Ubiquitin-like domain, UBLG5.
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Affiliation(s)
- Alessia Ruggiero
- Institute of Biostructures and Bioimaging, CNR, via Mezzocannone 16, Napoli, Italy
| | - Flavia Squeglia
- Institute of Biostructures and Bioimaging, CNR, via Mezzocannone 16, Napoli, Italy
| | - Maria Romano
- Institute of Biostructures and Bioimaging, CNR, via Mezzocannone 16, Napoli, Italy
| | - Luigi Vitagliano
- Institute of Biostructures and Bioimaging, CNR, via Mezzocannone 16, Napoli, Italy
| | - Alfonso De Simone
- Division of Molecular Biosciences, Imperial College London, SW7 2AZ, UK
| | - Rita Berisio
- Institute of Biostructures and Bioimaging, CNR, via Mezzocannone 16, Napoli, Italy.
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Nikitushkin VD, Demina GR, Shleeva MO, Guryanova SV, Ruggiero A, Berisio R, Kaprelyants AS. A product of RpfB and RipA joint enzymatic action promotes the resuscitation of dormant mycobacteria. FEBS J 2015; 282:2500-11. [PMID: 25846449 DOI: 10.1111/febs.13292] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 03/25/2015] [Accepted: 03/30/2015] [Indexed: 11/29/2022]
Abstract
Resuscitation-promoting factor proteins (Rpfs) are known to participate in reactivating the dormant forms of actinobacteria. Structural analysis of the Rpf catalytic domain demonstrates its similarity to lysozyme and to lytic transglycosylases - the groups of enzymes that cleave the β-1,4-glycosidic bond between N-acetylmuramic acid (MurNAc) and GlcNAc, and concomitantly form a 1,6-anhydro ring at the MurNAc residue. Analysis of the products formed from mycobacterial peptidoglycan hydrolysis reactions containing a mixture of RpfB and resuscitation-promoting factor interacting protein (RipA) allowed us to identify the suggested product of their action - N-acetylglucosaminyl-β(1 → 4)-N-glycolyl-1,6-anhydromuramyl-L-alanyl-D-isoglutamate. To identify the role of this resulting product in resuscitation, we used a synthetic 1,6-anhydrodisaccharide-dipeptide, and tested its ability to stimulate resuscitation by using the dormant Mycobacterium smegmatis model. It was found that the disaccharide-dipeptide was the minimal structure capable of resuscitating the dormant mycobacterial cells over the concentration range of 9-100 ng · mL(-1). The current study therefore provides the first insights into the molecular mechanism of resuscitation from dormancy involving a product of RpfB/RipA-mediated peptidoglycan cleavage.
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Affiliation(s)
- Vadim D Nikitushkin
- A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow, Russia
| | - Galina R Demina
- A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow, Russia
| | - Margarita O Shleeva
- A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow, Russia
| | - Svetlana V Guryanova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Alessia Ruggiero
- Institute of Biostructures and Bioimaging, C.N.R., Napoli, Italy
| | - Rita Berisio
- Institute of Biostructures and Bioimaging, C.N.R., Napoli, Italy
| | - Arseny S Kaprelyants
- A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow, Russia
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Puspita ID, Kitagawa W, Kamagata Y, Tanaka M, Nakatsu CH. Increase in Bacterial Colony Formation from a Permafrost Ice Wedge Dosed with a Tomitella biformata Recombinant Resuscitation-Promoting Factor Protein. Microbes Environ 2015; 30:151-6. [PMID: 25843055 PMCID: PMC4462925 DOI: 10.1264/jsme2.me14119] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Resuscitation-promoting factor (Rpf) is a protein that has been found in a number of different Actinobacteria species and has been shown to promote the growth of active cells and resuscitate dormant (non-dividing) cells. We previously reported the biological activity of an Rpf protein in Tomitella biformata AHU 1821T, an Actinobacteria isolated from a permafrost ice wedge. This protein is excreted outside the cell; however, few studies have investigated its contribution in environmental samples to the growth or resuscitation of bacteria other than the original host. Therefore, the aim of the present study was to determine whether Rpf from T. biformata impacted the cultivation of other bacteria from the permafrost ice wedge from which it was originally isolated. All experiments used recombinant Rpf proteins produced using a Rhodococcus erythropolis expression system. Dilutions of melted surface sterilized ice wedge samples mixed with different doses of the purified recombinant Rpf (rRpf) protein indicated that the highest concentration tested, 1250 pM, had a significantly (p <0.05) higher number of CFUs on agar plates after 8 d, approximately 14-fold higher than that on control plates without rRpf. 16S rRNA gene sequences revealed that all the colonies on plates were mainly related to Brevibacterium antiquum strain VKM Ac-2118 (AY243344), with 98–99% sequence identity. This species is also a member of the phylum Actinobacteria and was originally isolated from Siberian permafrost sediments. The results of the present study demonstrated that rRpf not only promoted the growth of T. biformata from which it was isolated, but also enhanced colony formation by another Actinobacteria in an environmental sample.
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Host cytokine responses induced after overnight stimulation with novel M. tuberculosis infection phase-dependent antigens show promise as diagnostic candidates for TB disease. PLoS One 2014; 9:e102584. [PMID: 25025278 PMCID: PMC4099213 DOI: 10.1371/journal.pone.0102584] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 06/20/2014] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND We previously identified Mycobacterium tuberculosis (M.tb) antigen-induced host markers that showed promise as TB diagnostic candidates in 7-day whole blood culture supernatants. The aim of the present study was to evaluate the utility of these markers further, and cross-compare results with short-term antigen stimulated and unstimulated culture supernatants. METHODS We recruited 15 culture confirmed TB cases and 15 non-TB cases from a high-TB endemic community in Cape Town, South Africa into a pilot case-control study from an on-going larger study. Blood samples collected from study participants were stimulated with 4 M.tb antigens that were previously identified as promising (ESAT6/CFP10 (early secreted), Rv2029c (latency), Rv2032 (latency) and Rv2389c (rpf)) in a 7-day or overnight culture assay. Supernatants were also collected form the standard QuantiFERON In Tube (QFT-IT) test. The levels of 26 host markers were evaluated in the three culture supernatants using the Luminex platform. RESULTS The unstimulated levels of CRP, Serum amyloid P (SAP) and serum amyloid A (SAA) and ESAT-6/CFP-10 specific IP-10 and SAA were amongst the best discriminatory markers in all 3 assays, ascertaining TB with AUC of 72-84%. Four-marker models accurately classified up to 92%, 100% and 100% of study participants in the overnight, 7-day and Quantiferon culture supernatants, respectively, after leave-one-out cross validation. CONCLUSION Unstimulated and antigen-specific levels of CRP, SAA, IP-10, MMP-2 and sCD40L hold promise as diagnostic candidates for TB disease in short-term stimulation assays. Larger studies are required to validate these findings but the data suggest that antigen-specific cytokine production and in particular mutimarker biosignatures might contribute to future diagnostic strategies.
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Huang W, Qi Y, Diao Y, Yang F, Zha X, Ren C, Huang D, Franken KLMC, Ottenhoff THM, Wu Q, Shen J. Use of resuscitation-promoting factor proteins improves the sensitivity of culture-based tuberculosis testing in special samples. Am J Respir Crit Care Med 2014; 189:612-4. [PMID: 24579840 DOI: 10.1164/rccm.201310-1899le] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Wei Huang
- 1 Anhui Medical UniversityHefei, PR China and
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18
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Puspita ID, Kamagata Y, Tanaka M, Asano K, Nakatsu CH. Are uncultivated bacteria really uncultivable? Microbes Environ 2012; 27:356-66. [PMID: 23059723 PMCID: PMC4103542 DOI: 10.1264/jsme2.me12092] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2012] [Accepted: 06/20/2012] [Indexed: 11/16/2022] Open
Abstract
Many strategies have been used to increase the number of bacterial cells that can be grown from environmental samples but cultivation efficiency remains a challenge for microbial ecologists. The difficulty of cultivating a fraction of bacteria in environmental samples can be classified into two non-exclusive categories. Bacterial taxa with no cultivated representatives for which appropriate laboratory conditions necessary for growth are yet to be identified. The other class is cells in a non-dividing state (also known as dormant or viable but not culturable cells) that require the removal or addition of certain factors to re-initiate growth. A number of strategies, from simple to high throughput techniques, are reviewed that have been used to increase the cultivation efficiency of environmental samples. Some of the underlying mechanisms that contribute to the success of these cultivation strategies are described. Overall this review emphasizes the need of researchers to first understand the factors that are hindering cultivation to identify the best strategies to improve cultivation efficiency.
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Affiliation(s)
- Indun Dewi Puspita
- Graduate School of Agriculture, Hokkaido University, N9 W9, Kita-ku, Sapporo, Hokkaido 060–8589,
Japan
| | - Yoichi Kamagata
- Graduate School of Agriculture, Hokkaido University, N9 W9, Kita-ku, Sapporo, Hokkaido 060–8589,
Japan
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 2–17 Tsukisamu-Higashi, Toyohira, Sapporo, Hokkaido 062–8517,
Japan
| | - Michiko Tanaka
- Graduate School of Agriculture, Hokkaido University, N9 W9, Kita-ku, Sapporo, Hokkaido 060–8589,
Japan
| | - Kozo Asano
- Graduate School of Agriculture, Hokkaido University, N9 W9, Kita-ku, Sapporo, Hokkaido 060–8589,
Japan
| | - Cindy H. Nakatsu
- Graduate School of Agriculture, Hokkaido University, N9 W9, Kita-ku, Sapporo, Hokkaido 060–8589,
Japan
- Department of Agronomy, Purdue University, West Lafayette, Indiana 47907,
USA
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Gengenbacher M, Kaufmann SHE. Mycobacterium tuberculosis: success through dormancy. FEMS Microbiol Rev 2012; 36:514-32. [PMID: 22320122 PMCID: PMC3319523 DOI: 10.1111/j.1574-6976.2012.00331.x] [Citation(s) in RCA: 464] [Impact Index Per Article: 38.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Revised: 12/22/2011] [Accepted: 01/31/2012] [Indexed: 01/21/2023] Open
Abstract
Tuberculosis (TB) remains a major health threat, killing nearly 2 million individuals around this globe, annually. The only vaccine, developed almost a century ago, provides limited protection only during childhood. After decades without the introduction of new antibiotics, several candidates are currently undergoing clinical investigation. Curing TB requires prolonged combination of chemotherapy with several drugs. Moreover, monitoring the success of therapy is questionable owing to the lack of reliable biomarkers. To substantially improve the situation, a detailed understanding of the cross-talk between human host and the pathogen Mycobacterium tuberculosis (Mtb) is vital. Principally, the enormous success of Mtb is based on three capacities: first, reprogramming of macrophages after primary infection/phagocytosis to prevent its own destruction; second, initiating the formation of well-organized granulomas, comprising different immune cells to create a confined environment for the host-pathogen standoff; third, the capability to shut down its own central metabolism, terminate replication, and thereby transit into a stage of dormancy rendering itself extremely resistant to host defense and drug treatment. Here, we review the molecular mechanisms underlying these processes, draw conclusions in a working model of mycobacterial dormancy, and highlight gaps in our understanding to be addressed in future research.
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Affiliation(s)
- Martin Gengenbacher
- Max Planck Institute for Infection Biology, Department of Immunology Charitéplatz 1, 10117 Berlin, Germany
| | - Stefan H. E. Kaufmann
- Max Planck Institute for Infection Biology, Department of Immunology Charitéplatz 1, 10117 Berlin, Germany
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20
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Chegou NN, Black GF, Loxton AG, Stanley K, Essone PN, Klein MR, Parida SK, Kaufmann SHE, Doherty TM, Friggen AH, Franken KL, Ottenhoff TH, Walzl G. Potential of novel Mycobacterium tuberculosis infection phase-dependent antigens in the diagnosis of TB disease in a high burden setting. BMC Infect Dis 2012; 12:10. [PMID: 22260319 PMCID: PMC3282638 DOI: 10.1186/1471-2334-12-10] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Accepted: 01/20/2012] [Indexed: 02/06/2023] Open
Abstract
Background Confirming tuberculosis (TB) disease in suspects in resource limited settings is challenging and calls for the development of more suitable diagnostic tools. Different Mycobacterium tuberculosis (M.tb) infection phase-dependent antigens may be differentially recognized in infected and diseased individuals and therefore useful as diagnostic tools for differentiating between M.tb infection states. In this study, we assessed the diagnostic potential of 118 different M.tb infection phase-dependent antigens in TB patients and household contacts (HHCs) in a high-burden setting. Methods Antigens were evaluated using the 7-day whole blood culture technique in 23 pulmonary TB patients and in 19 to 21 HHCs (total n = 101), who were recruited from a high-TB incidence community in Cape Town, South Africa. Interferon-gamma (IFN-γ) levels in culture supernatants were determined by ELISA. Results Eight classical TB vaccine candidate antigens, 51 DosR regulon encoded antigens, 23 TB reactivation antigens, 5 TB resuscitation promoting factors (rpfs), 6 starvation and 24 other stress response-associated TB antigens were evaluated in the study. The most promising antigens for ascertaining active TB were the rpfs (Rv0867c, Rv2389c, Rv2450c, Rv1009 and Rv1884c), with Areas under the receiver operating characteristics curves (AUCs) between 0.72 and 0.80. A combination of M.tb specific ESAT-6/CFP-10 fusion protein, Rv2624c and Rv0867c accurately predicted 73% of the TB patients and 80% of the non-TB cases after cross validation. Conclusions IFN-γ responses to TB rpfs show promise as TB diagnostic candidates and should be evaluated further for discrimination between M.tb infection states.
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Affiliation(s)
- Novel N Chegou
- DST/NRF Centre of Excellence for Biomedical Tuberculosis Research and MRC Centre for Molecular and Cellular Biology, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Health Sciences, Stellenbosch University, Tygerberg 7505, South Africa.
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Affiliation(s)
- Hyejin Kim
- Korean Institute of Tuberculosis, Osong, Chungcheongbuk-do, Korea
| | - Sungweon Ryoo
- Korean Institute of Tuberculosis, Osong, Chungcheongbuk-do, Korea
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Ruggiero A, Squeglia F, Pirone L, Correale S, Berisio R. Expression, purification, crystallization and preliminary X-ray crystallographic analysis of a major fragment of the resuscitation-promoting factor RpfB from Mycobacterium tuberculosis. Acta Crystallogr Sect F Struct Biol Cryst Commun 2010; 67:164-8. [PMID: 21206053 DOI: 10.1107/s1744309110049845] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2010] [Accepted: 11/29/2010] [Indexed: 11/10/2022]
Abstract
RpfB is required for the virulence and the resuscitation from dormancy of Mycobacterium tuberculosis, the bacterium responsible for tuberculosis. This protein is a cell-wall glycosidase that acts by cleaving peptidoglycans of the bacterial cell wall and therefore stimulates both bacterial growth and resuscitation from latency. RpfB consists of 362 residues organized into five domains. A long portion of RpfB, including its C-terminal catalytic domain, the G5 domain and one of its three DUF348 domains, which are of hitherto unknown structure and function, has been successfully crystallized using vapour-diffusion methods and seeding techniques. The crystals diffracted to 2.55 Å resolution and belonged to space group C222(1), with unit-cell parameters a=102.3, b=126.2, c=85.87 Å. Model building using phases derived from the combined use of multiwavelength anomalous dispersion and molecular replacement is in progress. The results obtained here will provide the first structural characterization of a DUF348 domain reported to date and will shed light on the functional role of the noncatalytic domains of RpfB.
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Affiliation(s)
- Alessia Ruggiero
- Institute of Biostructures and Bioimaging, CNR, Via Mezzocannone 16, I-80134 Napoli, Italy
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Abstract
Mycobacterium tuberculosis, which causes tuberculosis, remains a major human public health threat. This is largely due to a sizeable reservoir of latently infected individuals, who may relapse into active disease decades after first acquiring the infection. Furthermore, patients have a very slow response to treatment of active disease. Latency and antibiotic tolerance are commonly taken as a proxy for dormancy, a stable nonreplicative state. However, latency is a clinical term that is solely defined by a lack of disease indicators. The actual state of the bacterium in human latency is not well understood. Here we evaluate the results of several in vitro models of dormancy and consider the applicability of various animal models for studying aspects of human latency and resistance to killing by antibiotics. Furthermore, we propose a model for the initiation of dormancy and resuscitation during infection.
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Affiliation(s)
- Michael C Chao
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts 02115, USA.
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Wu X, Yang Y, Zhang J, Li B, Liang Y, Zhang C, Dong M. Comparison of antibody responses to seventeen antigens from Mycobacterium tuberculosis. Clin Chim Acta 2010; 411:1520-8. [PMID: 20599865 DOI: 10.1016/j.cca.2010.06.014] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2010] [Revised: 06/08/2010] [Accepted: 06/16/2010] [Indexed: 10/19/2022]
Abstract
BACKGROUND The detection of Mycobacteriumtuberculosis (MTB)-specific human antibodies has been an important diagnostic aid in the diagnosis of TB, especially for the bacterium-negative TB. The humoral antibody responses to different antigens of M.tuberculosis (MTB) are heterogeneous in active TB patients. Hence, detection of antibody responses to several MTB antigens may improve the sensitivity and specificity of serological diagnosis of active TB. METHODS Seventeen MTB antigens (38kD, 16kD, Ag85A, Ag85B, MPT32, MPT63, MPT64, Mtb39, MTB48, Mtb81, MTC28, Rv1009, ESAT6, CFP10, CFP10-ESAT6, katG, and LAM) were prepared by cloning, expression, and purification from E. coli, and their antigenicities were evaluated in the antibody responses of 210 active TB patients (103 sera from smear- or culture-positive patients, and 107 from smear- or culture-negative patients) and 192 healthy control (95 sera from purified protein derivative-negative healthy donors, and 97 sera from BCG-vaccinated individuals) by an enzyme-linked immunosorbent assay (ELISA). RESULTS The levels of antibodies against these antigens in bacterium-negative TB patients were significantly higher than that in healthy controls (p<0.001). The sensitivity with individual antigens to detect antibody responses ranged from 55.7 to 82.9%, with the specificity from 62.0 to 92.2%. Importantly, the sensitivity with five antigens (LAM, 38kD, katG, 16kD, and MPT63 or Mtb39) to detect antibody responses reached 69.5% (146/210), with a specificity of 91.1% (17/192), and the sensitivity with another five antigens (LAM, katG, 16kD, Mtb39 and Mtb81) to detect antibody responses reached 67.1% (141/210), with a specificity of 92.7% (14/192). CONCLUSIONS The combination of optimal multiple antigens to detect anti-MTB antibody responses increased the sensitivity and specificity. Therefore, detection of anti-MTB antibody responses with multiple antigens may be valuable in the clinical diagnosis of TB patients.
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Affiliation(s)
- Xueqiong Wu
- Institute for Tuberculosis Research, the 309th Hospital of Chinese PLA, Beijing 100091, China.
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