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Pazos-Rojas LA, Cuellar-Sánchez A, Romero-Cerón AL, Rivera-Urbalejo A, Van Dillewijn P, Luna-Vital DA, Muñoz-Rojas J, Morales-García YE, Bustillos-Cristales MDR. The Viable but Non-Culturable (VBNC) State, a Poorly Explored Aspect of Beneficial Bacteria. Microorganisms 2023; 12:39. [PMID: 38257865 PMCID: PMC10818521 DOI: 10.3390/microorganisms12010039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 12/20/2023] [Accepted: 12/22/2023] [Indexed: 01/24/2024] Open
Abstract
Many bacteria have the ability to survive in challenging environments; however, they cannot all grow on standard culture media, a phenomenon known as the viable but non-culturable (VBNC) state. Bacteria commonly enter the VBNC state under nutrient-poor environments or under stressful conditions. This review explores the concept of the VBNC state, providing insights into the beneficial bacteria known to employ this strategy. The investigation covers different chemical and physical factors that can induce the latency state, cell features, and gene expression observed in cells in the VBNC state. The review also covers the significance and applications of beneficial bacteria, methods of evaluating bacterial viability, the ability of bacteria to persist in environments associated with higher organisms, and the factors that facilitate the return to the culturable state. Knowledge about beneficial bacteria capable of entering the VBNC state remains limited; however, beneficial bacteria in this state could face adverse environmental conditions and return to a culturable state when the conditions become suitable and continue to exert their beneficial effects. Likewise, this unique feature positions them as potential candidates for healthcare applications, such as the use of probiotic bacteria to enhance human health, applications in industrial microbiology for the production of prebiotics and functional foods, and in the beer and wine industry. Moreover, their use in formulations to increase crop yields and for bacterial bioremediation offers an alternative pathway to harness their beneficial attributes.
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Affiliation(s)
- Laura Abisaí Pazos-Rojas
- Faculty of Stomatology, Meritorious Autonomous University of Puebla (BUAP), Puebla 72570, Mexico; (L.A.P.-R.); (A.R.-U.)
- Monterrey Institute of Technology, School of Engineering and Sciences, Monterrey 64700, Mexico; (A.C.-S.); (A.L.R.-C.); (D.A.L.-V.)
| | - Alma Cuellar-Sánchez
- Monterrey Institute of Technology, School of Engineering and Sciences, Monterrey 64700, Mexico; (A.C.-S.); (A.L.R.-C.); (D.A.L.-V.)
| | - Ana Laura Romero-Cerón
- Monterrey Institute of Technology, School of Engineering and Sciences, Monterrey 64700, Mexico; (A.C.-S.); (A.L.R.-C.); (D.A.L.-V.)
| | - América Rivera-Urbalejo
- Faculty of Stomatology, Meritorious Autonomous University of Puebla (BUAP), Puebla 72570, Mexico; (L.A.P.-R.); (A.R.-U.)
| | - Pieter Van Dillewijn
- Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain;
| | - Diego Armando Luna-Vital
- Monterrey Institute of Technology, School of Engineering and Sciences, Monterrey 64700, Mexico; (A.C.-S.); (A.L.R.-C.); (D.A.L.-V.)
| | - Jesús Muñoz-Rojas
- Ecology and Survival of Microorganisms Group, Laboratory of Microbial Molecular Ecology (LEMM), Center for Research in Microbiological Sciences, Institute of Sciences, Meritorious Autonomous University of Puebla (BUAP), Puebla 72570, Mexico;
| | - Yolanda Elizabeth Morales-García
- Ecology and Survival of Microorganisms Group, Laboratory of Microbial Molecular Ecology (LEMM), Center for Research in Microbiological Sciences, Institute of Sciences, Meritorious Autonomous University of Puebla (BUAP), Puebla 72570, Mexico;
- Faculty of Biological Sciences, Meritorious Autonomous University of Puebla (BUAP), Puebla 72570, Mexico
| | - María del Rocío Bustillos-Cristales
- Ecology and Survival of Microorganisms Group, Laboratory of Microbial Molecular Ecology (LEMM), Center for Research in Microbiological Sciences, Institute of Sciences, Meritorious Autonomous University of Puebla (BUAP), Puebla 72570, Mexico;
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Escobar-Chavarría O, Benitez-Guzman A, Jiménez-Vázquez I, Carrisoza-Urbina J, Arriaga-Pizano L, Huerta-Yépez S, Baay-Guzmán G, Gutiérrez-Pabello JA. Necrotic Cell Death and Inflammasome NLRP3 Activity in Mycobacterium bovis-Infected Bovine Macrophages. Cells 2023; 12:2079. [PMID: 37626889 PMCID: PMC10453650 DOI: 10.3390/cells12162079] [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: 06/28/2023] [Revised: 08/05/2023] [Accepted: 08/10/2023] [Indexed: 08/27/2023] Open
Abstract
Mycobacterium bovis is a facultative intracellular bacterium that produces cellular necrosis in granulomatous lesions in bovines. Although M. bovis-induced inflammation actively participates in granuloma development, its role in necrotic cell death and in bovine macrophages has not been fully explored. In this study, we evaluate the effect of M. bovis AN5 and its culture filtrate protein extract (CFPE) on inflammasome activation in bovine macrophages and its consequences on cell death. Our results show that both stimuli induce necrotic cell death starting 4 h after incubation. CFPE treatment and M. bovis infection also induce the maturation of IL-1β (>3000 pg/mL), oligomerization of ASC (apoptosis-associated speck-like protein containing CARD), and activation of caspase-1, following the canonical activation pathway of the NLRP3 inflammasome. Inhibiting the oligomerization of NLRP3 and caspase-1 decreases necrosis among the infected or CFPE-stimulated macrophages. Furthermore, histological lymph node sections of bovines naturally infected with M. bovis contained cleaved gasdermin D, mainly in macrophages and giant cells within the granulomas. Finally, the induction of cell death (apoptosis and pyroptosis) decreased the intracellular bacteria count in the infected bovine macrophages, suggesting that cell death helps to control the intracellular growth of the mycobacteria. Our results indicate that M. bovis induces pyroptosis-like cell death that is partially related to the NLRP3 inflammasome activation and that the cell death process could control bacterial growth.
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Affiliation(s)
- Omar Escobar-Chavarría
- Departamento de Microbiología e Inmunología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico; (O.E.-C.); (A.B.-G.); (I.J.-V.); (J.C.-U.)
| | - Alejandro Benitez-Guzman
- Departamento de Microbiología e Inmunología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico; (O.E.-C.); (A.B.-G.); (I.J.-V.); (J.C.-U.)
| | - Itzel Jiménez-Vázquez
- Departamento de Microbiología e Inmunología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico; (O.E.-C.); (A.B.-G.); (I.J.-V.); (J.C.-U.)
| | - Jacobo Carrisoza-Urbina
- Departamento de Microbiología e Inmunología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico; (O.E.-C.); (A.B.-G.); (I.J.-V.); (J.C.-U.)
| | - Lourdes Arriaga-Pizano
- Unidad de Investigación Médica en Inmunoquímica, Hospital de Especialidades del Centro Médico Siglo XXI, Instituto Mexicano del Seguro Social, Mexico City 06720, Mexico;
| | - Sara Huerta-Yépez
- Unidad de Investigación en Enfermedades Oncológicas, Hospital Infantil de México, Federico Gómez, Mexico City 06720, Mexico; (S.H.-Y.); (G.B.-G.)
| | - Guillermina Baay-Guzmán
- Unidad de Investigación en Enfermedades Oncológicas, Hospital Infantil de México, Federico Gómez, Mexico City 06720, Mexico; (S.H.-Y.); (G.B.-G.)
| | - José A. Gutiérrez-Pabello
- Departamento de Microbiología e Inmunología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico; (O.E.-C.); (A.B.-G.); (I.J.-V.); (J.C.-U.)
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Shade A. Microbiome rescue: directing resilience of environmental microbial communities. Curr Opin Microbiol 2023; 72:102263. [PMID: 36657335 DOI: 10.1016/j.mib.2022.102263] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 11/30/2022] [Accepted: 12/18/2022] [Indexed: 01/18/2023]
Abstract
Earth's climate crisis threatens to disrupt ecosystem services and destabilize food security. Microbiome management will be a crucial component of a comprehensive strategy to maintain stable microbinal functions for ecosystems and plants in the face of climate change. Microbiome rescue is the directed, community-level recovery of microbial populations and functions lost after an environmental disturbance. Microbiome rescue aims to propel a resilience trajectory for community functions. Rescue can be achieved via demographic, functional, adaptive, or evolutionary recovery of disturbance-sensitive populations. Various ecological mechanisms support rescue, including dispersal, reactivation from dormancy, functional redundancy, plasticity, and diversification, and these mechanisms can interact. Notably, controlling microbial reactivation from dormancy is a potentially fruitful but underexplored target for rescue.
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Affiliation(s)
- Ashley Shade
- Univ Lyon, CNRS, INSA Lyon, Université Claude Bernard Lyon 1, École Centrale de Lyon, Ampère, UMR5005, 69134 Ecully cedex, France; Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA; The Plant Resilience Institute, Michigan State University, East Lansing, MI 48824, USA; Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI 48824, USA; Program in Ecology, Evolution, and Behavior, Michigan State University, East Lansing, MI 48824, USA; The Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, USA.
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Intranasal multivalent adenoviral-vectored vaccine protects against replicating and dormant M.tb in conventional and humanized mice. NPJ Vaccines 2023; 8:25. [PMID: 36823425 PMCID: PMC9948798 DOI: 10.1038/s41541-023-00623-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 02/09/2023] [Indexed: 02/25/2023] Open
Abstract
Viral-vectored vaccines are highly amenable for respiratory mucosal delivery as a means of inducing much-needed mucosal immunity at the point of pathogen entry. Unfortunately, current monovalent viral-vectored tuberculosis (TB) vaccine candidates have failed to demonstrate satisfactory clinical protective efficacy. As such, there is a need to develop next-generation viral-vectored TB vaccine strategies which incorporate both vaccine antigen design and delivery route. In this study, we have developed a trivalent chimpanzee adenoviral-vectored vaccine to provide protective immunity against pulmonary TB through targeting antigens linked to the three different growth phases (acute/chronic/dormancy) of Mycobacterium tuberculosis (M.tb) by expressing an acute replication-associated antigen, Ag85A, a chronically expressed virulence-associated antigen, TB10.4, and a dormancy/resuscitation-associated antigen, RpfB. Single-dose respiratory mucosal immunization with our trivalent vaccine induced robust, sustained tissue-resident multifunctional CD4+ and CD8+ T-cell responses within the lung tissues and airways, which were further quantitatively and qualitatively improved following boosting of subcutaneously BCG-primed hosts. Prophylactic and therapeutic immunization with this multivalent trivalent vaccine in conventional BALB/c mice provided significant protection against not only actively replicating M.tb bacilli but also dormant, non-replicating persisters. Importantly, when used as a booster, it also provided marked protection in the highly susceptible C3HeB/FeJ mice, and a single respiratory mucosal inoculation was capable of significant protection in a humanized mouse model. Our findings indicate the great potential of this next-generation TB vaccine strategy and support its further clinical development for both prophylactic and therapeutic applications.
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Pal AK, Ghosh A. c-di-AMP signaling plays important role in determining antibiotic tolerance phenotypes of Mycobacterium smegmatis. Sci Rep 2022; 12:13127. [PMID: 35907936 PMCID: PMC9338955 DOI: 10.1038/s41598-022-17051-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 07/20/2022] [Indexed: 11/09/2022] Open
Abstract
In this study, we probe the role of secondary messenger c-di-AMP in drug tolerance, which includes both persister and resistant mutant characterization of Mycobacterium smegmatis. Specifically, with the use of c-di-AMP null and overproducing mutants, we showed how c-di-AMP plays a significant role in resistance mutagenesis against antibiotics with different mechanisms of action. We elucidated the specific molecular mechanism linking the elevated intracellular c-di-AMP level and high mutant generation and highlighted the significance of non-homology-based DNA repair. Further investigation enabled us to identify the unique mutational landscape of target and non-target mutation categories linked to intracellular c-di-AMP levels. Overall fitness cost of unique target mutations was estimated in different strain backgrounds, and then we showed the critical role of c-di-AMP in driving epistatic interactions between resistance genes, resulting in the evolution of multi-drug tolerance. Finally, we identified the role of c-di-AMP in persister cells regrowth and mutant enrichment upon cessation of antibiotic treatment.
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Affiliation(s)
- Aditya Kumar Pal
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, 560012, India
| | - Anirban Ghosh
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore, 560012, 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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Induration or erythema diameter not less than 5 mm as results of recombinant fusion protein ESAT6-CFP10 skin test for detecting M. tuberculosis infection. BMC Infect Dis 2020; 20:685. [PMID: 32948127 PMCID: PMC7501602 DOI: 10.1186/s12879-020-05413-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Accepted: 09/11/2020] [Indexed: 02/06/2023] Open
Abstract
Background Recombinant fusion protein ESAT6-CFP10 (EC) is a newly developed skin test reagent for detecting Mycobacterium tuberculosis (M. tuberculosis) infection. In this study, we evaluated whether induration and erythema could be used as diagnostic indicators for EC skin test to detect M. tuberculosis infection. Methods A total of 743 tuberculosis patients and 1514 healthy volunteers underwent an EC skin test. The diameters of induration and erythema were measured with Vernier caliper, 24 h, 48 h, and 72 h after skin testing. Related indicators of EC reagent diagnostic test were tested, and the diagnostic effects of the four diagnostic indicators for EC skin test were compared. Results The sensitivity of induration / erythema measurement was lower at 24 h after EC skin test than at 48 h or 72 h (P<0.01). There was no difference in consistency (P = 0.16) between induration with clinical diagnosis, and erythema with clinical diagnosis at 48 h (88.88 and 90.16%, Kappa value was 0.75 and 0.78, respectively). In patients, the sensitivity of erythema measurement was higher than induration measurement (P<0.01). In healthy volunteers, the specificity of erythema measurement was lower than induration at 24 h after skin test, but there was no difference at 48 h after skin test (P = 0.22). In BCG vaccination volunteers, the specificity of induration and erythema were higher than 90%. In addition, there was a high consistency of induration and erythema. When induration or erythema was used as a positive diagnostic indicator, the sensitivity of the EC skin test was improved, and was no different from the other three indicators in terms of specificity and consistency with clinical diagnosis. Conclusions Induration or erythema diameter not less than 5 mm could be used as a diagnostic indicator for detecting M. tuberculosis infection. Trial registration Phase III clinical trial of recombinant Mycobacterium tuberculosis ESAT6-CFP10 allergen; CTR20150695; registered in December 16, 2015.
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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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Uhía I, Krishnan N, Robertson BD. Characterising resuscitation promoting factor fluorescent-fusions in mycobacteria. BMC Microbiol 2018; 18:30. [PMID: 29649975 PMCID: PMC5898023 DOI: 10.1186/s12866-018-1165-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 03/15/2018] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Resuscitation promoting factor proteins (Rpfs) are peptidoglycan glycosidases capable of resuscitating dormant mycobacteria, and have been found to play a role in the pathogenesis of tuberculosis. However, the specific roles and localisation of each of the 5 Rpfs in Mycobacterium tuberculosis remain mostly unknown. In this work our aim was to construct fluorescent fusions of M. tuberculosis Rpf proteins as tools to investigate their function. RESULTS We found that Rpf-fusions to the fluorescent protein mCherry are functional and able to promote cell growth under different conditions. However, fusions to Enhanced Green Fluorescent Protein (EGFP) were non-functional in the assays used and none were secreted into the extracellular medium, which suggests Rpfs may be secreted via the Sec pathway. No specific cellular localization was observed for either set of fusions using time-lapse video microscopy. CONCLUSIONS We present the validation and testing of five M. tuberculosis Rpfs fused to mCherry, which are functional in resuscitation assays, but do not show any specific cellular localisation under the conditions tested. Our results suggest that Rpfs are likely to be secreted via the Sec pathway. We propose that such mCherry fusions will be useful tools for the further study of Rpf localisation, individual expression, and function.
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Affiliation(s)
- Iria Uhía
- MRC Centre for Molecular Bacteriology and Infection, Department of Medicine, Imperial College London, London, SW7 2AZ UK
| | - Nitya Krishnan
- MRC Centre for Molecular Bacteriology and Infection, Department of Medicine, Imperial College London, London, SW7 2AZ UK
| | - Brian D. Robertson
- MRC Centre for Molecular Bacteriology and Infection, Department of Medicine, Imperial College London, London, SW7 2AZ UK
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Pourazar Dizaji S, Taala A, Masoumi M, Ebrahimzadeh N, Fateh A, Siadat SD, Vaziri F. Sub-minimum inhibitory concentration of rifampin: a potential risk factor for resuscitation of Mycobacterium tuberculosis. Antimicrob Resist Infect Control 2017; 6:116. [PMID: 29163940 PMCID: PMC5686893 DOI: 10.1186/s13756-017-0273-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 11/08/2017] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Mycobacterium tuberculosis possesses five resuscitation-promoting factors, Rpf A to E, which are required for the resuscitation of dormancy in mycobacteria. This study explores the transcriptional profile of all five rpfs of M. tuberculosis, in response to sub-MIC concentration of rifampin, in multidrug and mono-rifampin resistant clinical isolates. METHODS Thirteen multidrug and two rifampin mono resistant clinical isolates were analyzed. Drug susceptibility testing and determination of MIC were performed. The relative expression of rpfs was measured, by real-time quantitative PCR. RESULTS A significant upregulation of relative expression (p < 0.05) was observed, as follows: 7/15(46.66%); 5/15(33.33%); 9/15(60%); 10/15(66.66%) and 9/15(60%) in rpfA, rpfB, rpfC, rpfD and rpfE, respectively. CONCLUSION Our results showed that the rpfs could be overexpressed in some extent in the presence of sub-MIC concentration of rifampin in multidrug and mono drug resistant M. tuberculosis. These results highlight the potential risk of sub-MIC rifampin concentrations, as a risk factor for tuberculosis reactivation.
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Affiliation(s)
- Shahin Pourazar Dizaji
- Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran
| | - Alireza Taala
- Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran
| | - Morteza Masoumi
- Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran
| | - Nayereh Ebrahimzadeh
- Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran
| | - Abolfazl Fateh
- Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran
- Microbiology Research Center (MRC), Pasteur Institute of Iran, Tehran, Iran
| | - Seyed Davar Siadat
- Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran
- Microbiology Research Center (MRC), Pasteur Institute of Iran, Tehran, Iran
| | - Farzam Vaziri
- Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran
- Microbiology Research Center (MRC), Pasteur Institute of Iran, Tehran, Iran
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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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Li Y, Chen J, Zhao M, Yang Z, Yue L, Zhang X. Promoting resuscitation of viable but nonculturable cells of Vibrio harveyi by a resuscitation-promoting factor-like protein YeaZ. J Appl Microbiol 2016; 122:338-346. [PMID: 27966258 DOI: 10.1111/jam.13342] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 10/19/2016] [Accepted: 10/31/2016] [Indexed: 12/16/2022]
Abstract
AIMS To demonstrate the resuscitation-promoting activities of recombinant YeaZ from Vibrio harveyi SF-1. METHODS AND RESULTS The gene of resuscitation-promoting factor YeaZ was cloned from genomic DNA of V. harveyi SF-1. The gene was expressed in Escherichia coli, and the expressed protein was purified by Ni2+ -affinity chromatography. A yeaZ mutant was constructed by using the suicide plasmid pNQ705 with homologous recombination. Disruption of yeaZ did not affect cell growth significantly in 2216 E broth at 28°C. The wild-type and mutant viable but nonculturable (VBNC) cells could be resuscitated by temperature upshift method. In addition, the recombinant YeaZ increased the culturable counts from 1·27 × 104 CFU per ml and 1·99 × 104 CFU per ml to 2·88 × 105 CFU per ml and 4·59 × 105 CFU per ml, respectively. After the VBNC cells of wild-type and mutant cells were maintained at 4°C for 120 days, no resuscitation was obtained by temperature upshift method, but addition of the recombinant YeaZ promoted the resuscitation of the wild-type and mutant cells, with the culturable cell counts of 1·13 × 103 and 1·44 × 103 CFU per ml, respectively. Disruption of yeaZ decreased the virulence of V. harveyi in zebrafish. The lethal dose 50% of the yeaZ null mutant was more than 10-fold higher than that of the wild-type cells. CONCLUSIONS The recombinant YeaZ could efficiently promote resuscitation of the wild-type and mutant cells of V. harveyi from VBNC to culturable state. The protein also promoted resuscitation of the VBNC wild-type and mutant cells, which were maintained at 4°C for 120 days and not recovered by temperature upshift method. Disruption of yeaZ decreased the virulence of V. harveyi in zebrafish. SIGNIFICANCE AND IMPACT OF THE STUDY Here, we show clear evidence of a resuscitation-promoting factor YeaZ of V. harveyi and the roles in resuscitation of the VBNC cells and its pathogenicity.
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Affiliation(s)
- Y Li
- College of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou, China.,School of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou, China
| | - J Chen
- School of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou, China
| | - M Zhao
- Department of Marine Biology, College of marine Life Science, Ocean University of China, Qingdao, China
| | - Z Yang
- College of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou, China.,School of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou, China
| | - L Yue
- School of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou, China
| | - X Zhang
- Department of Marine Biology, College of marine Life Science, Ocean University of China, Qingdao, China
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13
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Multifunctional T Cell Response to DosR and Rpf Antigens Is Associated with Protection in Long-Term Mycobacterium tuberculosis-Infected Individuals in Colombia. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2016; 23:813-824. [PMID: 27489136 DOI: 10.1128/cvi.00217-16] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 07/27/2016] [Indexed: 01/03/2023]
Abstract
Multifunctional T cells have been shown to be protective in chronic viral infections. In mycobacterial infections, however, evidence for a protective role of multifunctional T cells remains inconclusive. Short-term cultures of peripheral blood mononuclear cells stimulated with the Mycobacterium tuberculosis RD1 antigens 6-kDa early secretory antigenic target (ESAT6) and 10-kDa culture filtrate antigen (CFP10), which are induced in the early infection phase, have been mainly used to assess T cell multifunctionality, although long-term culture assays have been proposed to be more sensitive than short-term assays for assessment of memory T cells, which are essential for long-term immunity. Here we used a long-term culture assay system to study the T cell immune responses to the M. tuberculosis latency-associated DosR antigens and reactivation-associated Rpf antigens, compared to ESAT6 and CFP10, in patients with pulmonary tuberculosis (PTB) and household contacts of PTB patients with long-term latent tuberculosis infection (ltLTBI), in a community in which M. tuberculosis is endemic. Our results showed that the DosR antigens Rv1737c (narK2) and Rv2029c (pfkB) and the Rv2389c (rpfD) antigen of M. tuberculosis induced higher frequencies of CD4+ or CD8+ mono- or bifunctional (but not multifunctional) T cells producing interferon gamma (IFN-γ) and/or tumor necrosis alpha (TNF-α) in ltLTBI, compared to PTB. Moreover, the frequencies of CD4+ and/or CD8+ T cells with a CD45RO+ CD27+ phenotype were higher in ltLTBI than in PTB. Thus, the immune responses to selected DosR and Rpf antigens may be associated with long-term latency, correlating with protection from M. tuberculosis reactivation in ltLTBI. Further study of the functional and memory phenotypes may contribute to further discrimination between the different states of M. tuberculosis infections.
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14
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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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15
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Kell D, Potgieter M, Pretorius E. Individuality, phenotypic differentiation, dormancy and 'persistence' in culturable bacterial systems: commonalities shared by environmental, laboratory, and clinical microbiology. F1000Res 2015; 4:179. [PMID: 26629334 PMCID: PMC4642849 DOI: 10.12688/f1000research.6709.2] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/04/2015] [Indexed: 01/28/2023] Open
Abstract
For bacteria, replication mainly involves growth by binary fission. However, in a very great many natural environments there are examples of phenotypically dormant, non-growing cells that do not replicate immediately and that are phenotypically 'nonculturable' on media that normally admit their growth. They thereby evade detection by conventional culture-based methods. Such dormant cells may also be observed in laboratory cultures and in clinical microbiology. They are usually more tolerant to stresses such as antibiotics, and in clinical microbiology they are typically referred to as 'persisters'. Bacterial cultures necessarily share a great deal of relatedness, and inclusive fitness theory implies that there are conceptual evolutionary advantages in trading a variation in growth rate against its mean, equivalent to hedging one's bets. There is much evidence that bacteria exploit this strategy widely. We here bring together data that show the commonality of these phenomena across environmental, laboratory and clinical microbiology. Considerable evidence, using methods similar to those common in environmental microbiology, now suggests that many supposedly non-communicable, chronic and inflammatory diseases are exacerbated (if not indeed largely caused) by the presence of dormant or persistent bacteria (the ability of whose components to cause inflammation is well known). This dormancy (and resuscitation therefrom) often reflects the extent of the availability of free iron. Together, these phenomena can provide a ready explanation for the continuing inflammation common to such chronic diseases and its correlation with iron dysregulation. This implies that measures designed to assess and to inhibit or remove such organisms (or their access to iron) might be of much therapeutic benefit.
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Affiliation(s)
- Douglas Kell
- School of Chemistry and The Manchester Institute of Biotechnology, The University of Manchester, Manchester, Lancashire, M1 7DN, UK
| | - Marnie Potgieter
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Arcadia, 0007, South Africa
| | - Etheresia Pretorius
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Arcadia, 0007, South Africa
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16
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Kell D, Potgieter M, Pretorius E. Individuality, phenotypic differentiation, dormancy and 'persistence' in culturable bacterial systems: commonalities shared by environmental, laboratory, and clinical microbiology. F1000Res 2015; 4:179. [PMID: 26629334 DOI: 10.12688/f1000research.6709.1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/29/2015] [Indexed: 01/28/2023] Open
Abstract
For bacteria, replication mainly involves growth by binary fission. However, in a very great many natural environments there are examples of phenotypically dormant, non-growing cells that do not replicate immediately and that are phenotypically 'nonculturable' on media that normally admit their growth. They thereby evade detection by conventional culture-based methods. Such dormant cells may also be observed in laboratory cultures and in clinical microbiology. They are usually more tolerant to stresses such as antibiotics, and in clinical microbiology they are typically referred to as 'persisters'. Bacterial cultures necessarily share a great deal of relatedness, and inclusive fitness theory implies that there are conceptual evolutionary advantages in trading a variation in growth rate against its mean, equivalent to hedging one's bets. There is much evidence that bacteria exploit this strategy widely. We here bring together data that show the commonality of these phenomena across environmental, laboratory and clinical microbiology. Considerable evidence, using methods similar to those common in environmental microbiology, now suggests that many supposedly non-communicable, chronic and inflammatory diseases are exacerbated (if not indeed largely caused) by the presence of dormant or persistent bacteria (the ability of whose components to cause inflammation is well known). This dormancy (and resuscitation therefrom) often reflects the extent of the availability of free iron. Together, these phenomena can provide a ready explanation for the continuing inflammation common to such chronic diseases and its correlation with iron dysregulation. This implies that measures designed to assess and to inhibit or remove such organisms (or their access to iron) might be of much therapeutic benefit.
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Affiliation(s)
- Douglas Kell
- School of Chemistry and The Manchester Institute of Biotechnology, The University of Manchester, Manchester, Lancashire, M1 7DN, UK
| | - Marnie Potgieter
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Arcadia, 0007, South Africa
| | - Etheresia Pretorius
- Department of Physiology, Faculty of Health Sciences, University of Pretoria, Arcadia, 0007, South Africa
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17
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Mavrici D, Prigozhin DM, Alber T. Mycobacterium tuberculosis RpfE crystal structure reveals a positively charged catalytic cleft. Protein Sci 2015; 23:481-7. [PMID: 24452911 DOI: 10.1002/pro.2431] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 01/17/2014] [Accepted: 01/17/2014] [Indexed: 11/07/2022]
Abstract
Resuscitation promoting factor (Rpf) proteins, which hydrolyze the sugar chains in cell-wall peptidoglycan (PG), play key roles in prokaryotic cell elongation, division, and escape from dormancy to vegetative growth. Like other bacteria, Mycobacterium tuberculosis (Mtb) expresses multiple Rpfs, none of which is individually essential. This redundancy has left unclear the distinct functions of the different Rpfs. To explore the distinguishing characteristics of the five Mtb Rpfs, we determined the crystal structure of the RpfE catalytic domain. The protein adopts the characteristic Rpf fold, but the catalytic cleft is narrower compared to Mtb RpfB. Also in contrast to RpfB, in which the substrate-binding surfaces are negatively charged, the corresponding RpfE catalytic pocket and predicted peptide-binding sites are more positively charged at neutral pH. The complete reversal of the electrostatic potential of the substrate-binding site suggests that the different Rpfs function optimally at different pHs or most efficiently hydrolyze different micro-domains of PG. These studies provide insights into the molecular determinants of the evolution of functional specialization in Rpfs.
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Affiliation(s)
- Daniela Mavrici
- Department of Molecular and Cell Biology and California Institute for Quantitative Biosciences, University of California, Berkeley, California, 94720
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18
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Zhao S, Song X, Zhao Y, Qiu Y, Mao F, Zhang C, Bai B, Zhang H, Wu S, Shi C. Protective and therapeutic effects of the resuscitation-promoting factor domain and its mutants against Mycobacterium tuberculosis in mice. Pathog Dis 2015; 73:ftu025. [DOI: 10.1093/femspd/ftu025] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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19
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Immunoinformatics study on highly expressed Mycobacterium tuberculosis genes during infection. Tuberculosis (Edinb) 2014; 94:475-81. [DOI: 10.1016/j.tube.2014.06.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 06/04/2014] [Accepted: 06/08/2014] [Indexed: 12/22/2022]
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20
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Ramamurthy T, Ghosh A, Pazhani GP, Shinoda S. Current Perspectives on Viable but Non-Culturable (VBNC) Pathogenic Bacteria. Front Public Health 2014; 2:103. [PMID: 25133139 PMCID: PMC4116801 DOI: 10.3389/fpubh.2014.00103] [Citation(s) in RCA: 251] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 07/15/2014] [Indexed: 11/07/2022] Open
Abstract
Under stress conditions, many species of bacteria enter into starvation mode of metabolism or a physiologically viable but non-culturable (VBNC) state. Several human pathogenic bacteria have been reported to enter into the VBNC state under these conditions. The pathogenic VBNC bacteria cannot be grown using conventional culture media, although they continue to retain their viability and express their virulence. Though there have been debates on the VBNC concept in the past, several molecular studies have shown that not only can the VBNC state be induced under in vitro conditions but also that resuscitation from this state is possible under appropriate conditions. The most notable advance in resuscitating VBNC bacteria is the discovery of resuscitation-promoting factor (Rpf), which is a bacterial cytokines found in both Gram-positive and Gram-negative organisms. VBNC state is a survival strategy adopted by the bacteria, which has important implication in several fields, including environmental monitoring, food technology, and infectious disease management; and hence it is important to investigate the association of bacterial pathogens under VBNC state and the water/foodborne outbreaks. In this review, we describe various aspects of VBNC bacteria, which include their proteomic and genetic profiles under the VBNC state, conditions of resuscitation, methods of detection, antibiotic resistance, and observations on Rpf.
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Affiliation(s)
| | - Amit Ghosh
- National Institute of Cholera and Enteric Diseases (NICED) , Kolkata , India
| | - Gururaja P Pazhani
- National Institute of Cholera and Enteric Diseases (NICED) , Kolkata , India
| | - Sumio Shinoda
- Collaborative Research Center of Okayama University for Infectious Diseases in India, NICED , Kolkata , India
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21
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Machowski EE, Senzani S, Ealand C, Kana BD. Comparative genomics for mycobacterial peptidoglycan remodelling enzymes reveals extensive genetic multiplicity. BMC Microbiol 2014; 14:75. [PMID: 24661741 PMCID: PMC3987819 DOI: 10.1186/1471-2180-14-75] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Accepted: 03/12/2014] [Indexed: 02/04/2023] Open
Abstract
Background Mycobacteria comprise diverse species including non-pathogenic, environmental organisms, animal disease agents and human pathogens, notably Mycobacterium tuberculosis. Considering that the mycobacterial cell wall constitutes a significant barrier to drug penetration, the aim of this study was to conduct a comparative genomics analysis of the repertoire of enzymes involved in peptidoglycan (PG) remodelling to determine the potential of exploiting this area of bacterial metabolism for the discovery of new drug targets. Results We conducted an in silico analysis of 19 mycobacterial species/clinical strains for the presence of genes encoding resuscitation promoting factors (Rpfs), penicillin binding proteins, endopeptidases, L,D-transpeptidases and N-acetylmuramoyl-L-alanine amidases. Our analysis reveals extensive genetic multiplicity, allowing for classification of mycobacterial species into three main categories, primarily based on their rpf gene complement. These include the M. tuberculosis Complex (MTBC), other pathogenic mycobacteria and environmental species. The complement of these genes within the MTBC and other mycobacterial pathogens is highly conserved. In contrast, environmental strains display significant genetic expansion in most of these gene families. Mycobacterium leprae retains more than one functional gene from each enzyme family, underscoring the importance of genetic multiplicity for PG remodelling. Notably, the highest degree of conservation is observed for N-acetylmuramoyl-L-alanine amidases suggesting that these enzymes are essential for growth and survival. Conclusion PG remodelling enzymes in a range of mycobacterial species are associated with extensive genetic multiplicity, suggesting functional diversification within these families of enzymes to allow organisms to adapt.
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Affiliation(s)
| | | | | | - Bavesh Davandra Kana
- DST/NRF Centre of Excellence for Biomedical TB Research, Faculty of Health Sciences, University of the Witwatersrand, National Health Laboratory Service, P,O, Box 1038, Johannesburg 2000, South Africa.
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22
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Caruso G, Angotti R, Molinaro F, Benicchi E, Cerchia E, Messina M. Cervical Lymphadenitis by Mycobacterium triplex in an Immunocompetent Child: Case Report and Review. Indian J Microbiol 2014; 53:241-4. [PMID: 24426116 DOI: 10.1007/s12088-013-0367-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Accepted: 01/29/2013] [Indexed: 11/26/2022] Open
Abstract
Mycobacterium triplex was first described in 1996. This nontuberculous Mycobacterium causes a severe pulmonary disease in immunocompromised patients but it can involve also healthy patients. A literature search was made on the PubMed database and it produced only few cases of children with cervical lymphadenitis due to this Mycobacterium Triplex. We are describing a case of M. triplex cervical lymphadenitis in an immunocompetent child.
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Affiliation(s)
- G Caruso
- ENT Unit, University of Siena, 53100 Siena, Italy
| | - R Angotti
- Division of Pediatric Surgery, Department of Medical, Surgical and Neurological Sciences, University of Siena, Policlinico "Le Scotte" Viale Bracci 16, 53100 Siena, Italy
| | - F Molinaro
- Division of Pediatric Surgery, Department of Medical, Surgical and Neurological Sciences, University of Siena, Policlinico "Le Scotte" Viale Bracci 16, 53100 Siena, Italy
| | - E Benicchi
- ENT Unit, University of Siena, 53100 Siena, Italy
| | - E Cerchia
- Division of Pediatric Surgery, Department of Medical, Surgical and Neurological Sciences, University of Siena, Policlinico "Le Scotte" Viale Bracci 16, 53100 Siena, Italy
| | - M Messina
- Division of Pediatric Surgery, Department of Medical, Surgical and Neurological Sciences, University of Siena, Policlinico "Le Scotte" Viale Bracci 16, 53100 Siena, Italy
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