1
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Khan H, Paul P, Goar H, Bamniya B, Baid N, Sarkar D. Mycobacterium tuberculosis PhoP integrates stress response to intracellular survival by regulating cAMP level. eLife 2024; 13:RP92136. [PMID: 38739431 PMCID: PMC11090507 DOI: 10.7554/elife.92136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2024] Open
Abstract
Survival of Mycobacterium tuberculosis within the host macrophages requires the bacterial virulence regulator PhoP, but the underlying reason remains unknown. 3',5'-Cyclic adenosine monophosphate (cAMP) is one of the most widely used second messengers, which impacts a wide range of cellular responses in microbial pathogens including M. tuberculosis. Herein, we hypothesized that intra-bacterial cAMP level could be controlled by PhoP since this major regulator plays a key role in bacterial responses against numerous stress conditions. A transcriptomic analysis reveals that PhoP functions as a repressor of cAMP-specific phosphodiesterase (PDE) Rv0805, which hydrolyzes cAMP. In keeping with these results, we find specific recruitment of the regulator within the promoter region of rv0805 PDE, and absence of phoP or ectopic expression of rv0805 independently accounts for elevated PDE synthesis, leading to the depletion of intra-bacterial cAMP level. Thus, genetic manipulation to inactivate PhoP-rv0805-cAMP pathway decreases cAMP level, stress tolerance, and intracellular survival of the bacillus.
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Affiliation(s)
- Hina Khan
- CSIR, Institute of Microbial TechnologyChandigarhIndia
| | - Partha Paul
- CSIR, Institute of Microbial TechnologyChandigarhIndia
| | - Harsh Goar
- CSIR, Institute of Microbial TechnologyChandigarhIndia
| | - Bhanwar Bamniya
- CSIR, Institute of Microbial TechnologyChandigarhIndia
- Academy of Scientific and Innovative ResearchGhaziabadIndia
| | - Navin Baid
- CSIR, Institute of Microbial TechnologyChandigarhIndia
| | - Dibyendu Sarkar
- CSIR, Institute of Microbial TechnologyChandigarhIndia
- Academy of Scientific and Innovative ResearchGhaziabadIndia
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2
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Dechow SJ, Abramovitch RB. Targeting Mycobacterium tuberculosis pH-driven adaptation. MICROBIOLOGY (READING, ENGLAND) 2024; 170:001458. [PMID: 38717801 PMCID: PMC11165653 DOI: 10.1099/mic.0.001458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 04/17/2024] [Indexed: 06/13/2024]
Abstract
Mycobacterium tuberculosis (Mtb) senses and adapts to host environmental cues as part of its pathogenesis. One important cue sensed by Mtb is the acidic pH of its host niche - the macrophage. Acidic pH induces widespread transcriptional and metabolic remodelling in Mtb. These adaptations to acidic pH can lead Mtb to slow its growth and promote pathogenesis and antibiotic tolerance. Mutants defective in pH-dependent adaptations exhibit reduced virulence in macrophages and animal infection models, suggesting that chemically targeting these pH-dependent pathways may have therapeutic potential. In this review, we discuss mechanisms by which Mtb regulates its growth and metabolism at acidic pH. Additionally, we consider the therapeutic potential of disrupting pH-driven adaptations in Mtb and review the growing class of compounds that exhibit pH-dependent activity or target pathways important for adaptation to acidic pH.
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Affiliation(s)
- Shelby J. Dechow
- Department of Microbiology, Genetics and Immunology, Michigan State University, East Lansing, MI 48824, USA
| | - Robert B. Abramovitch
- Department of Microbiology, Genetics and Immunology, Michigan State University, East Lansing, MI 48824, USA
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3
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Bosch B, DeJesus MA, Schnappinger D, Rock JM. Weak links: Advancing target-based drug discovery by identifying the most vulnerable targets. Ann N Y Acad Sci 2024; 1535:10-19. [PMID: 38595325 DOI: 10.1111/nyas.15139] [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] [Indexed: 04/11/2024]
Abstract
Mycobacterium tuberculosis remains the most common infectious killer worldwide despite decades of antitubercular drug development. Effectively controlling the tuberculosis (TB) pandemic will require innovation in drug discovery. In this review, we provide a brief overview of the two main approaches to discovering new TB drugs-phenotypic screens and target-based drug discovery-and outline some of the limitations of each method. We then explore recent advances in genetic tools that aim to overcome some of these limitations. In particular, we highlight a novel metric to prioritize essential targets, termed vulnerability. Stratifying targets based on their vulnerability presents new opportunities for future target-based drug discovery campaigns.
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Affiliation(s)
- Barbara Bosch
- Laboratory of Host-Pathogen Biology, The Rockefeller University, New York, New York, USA
| | - Michael A DeJesus
- Laboratory of Host-Pathogen Biology, The Rockefeller University, New York, New York, USA
| | - Dirk Schnappinger
- Department of Microbiology and Immunology, Weill Cornell Medicine, New York, New York, USA
| | - Jeremy M Rock
- Laboratory of Host-Pathogen Biology, The Rockefeller University, New York, New York, USA
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4
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Zhang Q, Yu X, Yang Y, Ruan J, Zou Y, Wu S, Chen F, Zhu R. Enhanced ammonia removal in tidal flow constructed wetland by incorporating steel slag: Performance, microbial community, and heavy metal release. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 922:171333. [PMID: 38423325 DOI: 10.1016/j.scitotenv.2024.171333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 02/25/2024] [Accepted: 02/26/2024] [Indexed: 03/02/2024]
Abstract
Utilizing alkaline solid wastes, such as steel slag, as substrates in tidal flow constructed wetlands (TFCWs) can effectively neutralize the acidity generated by nitrification. However, the impacts of steel slag on microbial communities and the potential risk of heavy metal release remain poorly understood. To address these knowledge gaps, this study compared the performance and microbial community structure of TFCWs filled with a mixture of steel slag and zeolite (TFCW-S) to those filled with zeolite alone (TFCW-Z). TFCW-S exhibited a much higher NH4+-N removal efficiency (98.35 %) than TFCW-Z (55.26 %). Additionally, TFCW-S also achieved better TN and TP removal. The steel slag addition helped maintain the TFCW-S effluent pH at around 7.5, while the TFCW-Z effluent pH varied from 3.74 to 6.25. The nitrification and denitrification intensities in TFCW-S substrates were significantly higher than those in TFCW-Z, consistent with the observed removal performance. Moreover, steel slag did not cause excessive heavy metal release, as the effluent concentrations were below the standard limits. Microbial community analysis revealed that ammonia-oxidizing bacteria, ammonia-oxidizing archaea, and complete ammonia-oxidizing bacteria coexisted in both TFCWs, albeit with different compositions. Furthermore, the enrichment of heterotrophic nitrification-aerobic denitrification bacteria in TFCW-S likely contributed to the high NH4+-N removal. In summary, these findings demonstrate that the combined use of steel slag and zeolite in TFCWs creates favorable pH conditions for ammonia-oxidizing microorganisms, leading to efficient ammonia removal in an environmentally friendly manner.
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Affiliation(s)
- Quan Zhang
- CAS Key Laboratory of Mineralogy and Metallogeny & Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 511 Kehua Street, 510640 Guangzhou, China; CAS Center for Excellence in Deep Earth Science, 511 Kehua Street, 510640 Guangzhou, China; University of Chinese Academy of Sciences, 19 Yuquan Road, 100049 Beijing, China
| | - Xingyu Yu
- CAS Key Laboratory of Mineralogy and Metallogeny & Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 511 Kehua Street, 510640 Guangzhou, China; CAS Center for Excellence in Deep Earth Science, 511 Kehua Street, 510640 Guangzhou, China; University of Chinese Academy of Sciences, 19 Yuquan Road, 100049 Beijing, China
| | - Yongqiang Yang
- CAS Key Laboratory of Mineralogy and Metallogeny & Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 511 Kehua Street, 510640 Guangzhou, China; CAS Center for Excellence in Deep Earth Science, 511 Kehua Street, 510640 Guangzhou, China.
| | - Jingjun Ruan
- CAS Key Laboratory of Mineralogy and Metallogeny & Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 511 Kehua Street, 510640 Guangzhou, China; CAS Center for Excellence in Deep Earth Science, 511 Kehua Street, 510640 Guangzhou, China; University of Chinese Academy of Sciences, 19 Yuquan Road, 100049 Beijing, China
| | - Yuhuan Zou
- CAS Key Laboratory of Mineralogy and Metallogeny & Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 511 Kehua Street, 510640 Guangzhou, China; CAS Center for Excellence in Deep Earth Science, 511 Kehua Street, 510640 Guangzhou, China; University of Chinese Academy of Sciences, 19 Yuquan Road, 100049 Beijing, China
| | - Shijun Wu
- CAS Key Laboratory of Mineralogy and Metallogeny & Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 511 Kehua Street, 510640 Guangzhou, China; CAS Center for Excellence in Deep Earth Science, 511 Kehua Street, 510640 Guangzhou, China
| | - Fanrong Chen
- CAS Key Laboratory of Mineralogy and Metallogeny & Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 511 Kehua Street, 510640 Guangzhou, China; CAS Center for Excellence in Deep Earth Science, 511 Kehua Street, 510640 Guangzhou, China
| | - Runliang Zhu
- CAS Key Laboratory of Mineralogy and Metallogeny & Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 511 Kehua Street, 510640 Guangzhou, China; CAS Center for Excellence in Deep Earth Science, 511 Kehua Street, 510640 Guangzhou, China
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5
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Stupar M, Tan L, Kerr ED, De Voss CJ, Forde BM, Schulz BL, West NP. TcrXY is an acid-sensing two-component transcriptional regulator of Mycobacterium tuberculosis required for persistent infection. Nat Commun 2024; 15:1615. [PMID: 38388565 PMCID: PMC10883919 DOI: 10.1038/s41467-024-45343-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 01/22/2024] [Indexed: 02/24/2024] Open
Abstract
The ability of Mycobacterium tuberculosis (Mtb) to persist in the host complicates and prolongs tuberculosis (TB) patient chemotherapy. Here we demonstrate that a neglected two-component system (TCS) of Mtb, TcrXY, is an autoregulated acid-sensing TCS that controls a functionally diverse 70-gene regulon required for bacterial persistence. Characterisation of two representatives of this regulon, Rv3706c and Rv3705A, implicate these genes as key determinants for the survival of Mtb in vivo by serving as important effectors to mitigate redox stress at acidic pH. We show that genetic silencing of the response regulator tcrX using CRISPR interference attenuates the persistence of Mtb during chronic mouse infection and improves treatment with the two front-line anti-TB drugs, rifampicin and isoniazid. We propose that targeting TcrXY signal transduction blocks the ability of Mtb to sense and respond to acid stress, resulting in a disordered program of persistence to render the organism vulnerable to existing TB chemotherapy.
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Affiliation(s)
- Miljan Stupar
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, The University of Queensland, Brisbane, Australia
| | - Lendl Tan
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, The University of Queensland, Brisbane, Australia
| | - Edward D Kerr
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, The University of Queensland, Brisbane, Australia
| | - Christopher J De Voss
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, The University of Queensland, Brisbane, Australia
| | - Brian M Forde
- Faculty of Medicine, UQ Centre for Clinical Research, The University of Queensland, Brisbane, Australia
| | - Benjamin L Schulz
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, The University of Queensland, Brisbane, Australia
| | - Nicholas P West
- School of Chemistry and Molecular Biosciences, Australian Infectious Disease Research Centre, The University of Queensland, Brisbane, Australia.
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6
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Chen Y, MacGilvary NJ, Tan S. Mycobacterium tuberculosis response to cholesterol is integrated with environmental pH and potassium levels via a lipid metabolism regulator. PLoS Genet 2024; 20:e1011143. [PMID: 38266039 PMCID: PMC10843139 DOI: 10.1371/journal.pgen.1011143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 02/05/2024] [Accepted: 01/19/2024] [Indexed: 01/26/2024] Open
Abstract
Successful colonization of the host requires Mycobacterium tuberculosis (Mtb) to sense and respond coordinately to disparate environmental cues during infection and adapt its physiology. However, how Mtb response to environmental cues and the availability of key carbon sources may be integrated is poorly understood. Here, by exploiting a reporter-based genetic screen, we have unexpectedly found that overexpression of transcription factors involved in Mtb lipid metabolism altered the dampening effect of low environmental potassium concentrations ([K+]) on the pH response of Mtb. Cholesterol is a major carbon source for Mtb during infection, and transcriptional analyses revealed that Mtb response to acidic pH was augmented in the presence of cholesterol and vice versa. Strikingly, deletion of the putative lipid regulator mce3R had little effect on Mtb transcriptional response to acidic pH or cholesterol individually, but resulted specifically in loss of cholesterol response augmentation in the simultaneous presence of acidic pH. Similarly, while mce3R deletion had little effect on Mtb response to low environmental [K+] alone, augmentation of the low [K+] response by the simultaneous presence of cholesterol was lost in the mutant. Finally, a mce3R deletion mutant was attenuated for growth in foamy macrophages and for colonization in a murine infection model that recapitulates caseous necrotic lesions and the presence of foamy macrophages. These findings reveal the critical coordination between Mtb response to environmental cues and cholesterol, a vital carbon source, and establishes Mce3R as a transcription factor that crucially serves to integrate these signals.
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Affiliation(s)
- Yue Chen
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - Nathan J. MacGilvary
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
- Current affiliation: Department of Molecular, Cell, and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
| | - Shumin Tan
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
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7
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Adhyapak P, Liang K, Duan M, Kapoor S. Effect of Host Cholesterol on the Membrane Dynamics of Outer Membrane Lipids of Mycobacteria. Chem Asian J 2023; 18:e202300697. [PMID: 37846643 DOI: 10.1002/asia.202300697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/16/2023] [Accepted: 10/17/2023] [Indexed: 10/18/2023]
Abstract
The ability of Mycobacterium tuberculosis to remain dormant after primary infection represents the prime cause of new TB cases throughout the world. Hence, diagnosis and treatment of individuals hosting dormant mycobacterium is one of the crucial strategies to be adopted for the prevention of Tuberculosis. Among many strategies unleashed by the latent bacterium, one of them is scavenging host cholesterol for carbon source. Cholesterol modifies lipid membranes over many scales and here, its effect on mycobacterial membrane biophysics and the subsequent effect on partitioning of antibiotics into cholesterol- enriched mycobacterial membranes was investigated. Our research showed that cholesterol alters the phase state behavior of mycobacterial outer membrane lipids by enhancing the overall membrane order at the headgroup and acyl chain region and is integrated into both ordered and disordered domains/phases, with a preference for the latter. Exogenous cholesterol further alters the drug partitioning behavior of structurally different drugs, pointing to a larger clinical potential of using more hydrophobic medications to target dormant bacteria.
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Affiliation(s)
- Pranav Adhyapak
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, 400076, India
| | - Kuan Liang
- National Centre for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, Hubei, China
| | - Mojie Duan
- National Centre for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, Hubei, China
| | - Shobhna Kapoor
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, 400076, India
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8
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Malla TN, Zielinski K, Aldama L, Bajt S, Feliz D, Hayes B, Hunter M, Kupitz C, Lisova S, Knoska J, Martin-Garcia JM, Mariani V, Pandey S, Poudyal I, Sierra RG, Tolstikova A, Yefanov O, Yoon CH, Ourmazd A, Fromme P, Schwander P, Barty A, Chapman HN, Stojkovic EA, Batyuk A, Boutet S, Phillips GN, Pollack L, Schmidt M. Heterogeneity in M. tuberculosis β-lactamase inhibition by Sulbactam. Nat Commun 2023; 14:5507. [PMID: 37679343 PMCID: PMC10485065 DOI: 10.1038/s41467-023-41246-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 08/27/2023] [Indexed: 09/09/2023] Open
Abstract
For decades, researchers have elucidated essential enzymatic functions on the atomic length scale by tracing atomic positions in real-time. Our work builds on possibilities unleashed by mix-and-inject serial crystallography (MISC) at X-ray free electron laser facilities. In this approach, enzymatic reactions are triggered by mixing substrate or ligand solutions with enzyme microcrystals. Here, we report in atomic detail (between 2.2 and 2.7 Å resolution) by room-temperature, time-resolved crystallography with millisecond time-resolution (with timepoints between 3 ms and 700 ms) how the Mycobacterium tuberculosis enzyme BlaC is inhibited by sulbactam (SUB). Our results reveal ligand binding heterogeneity, ligand gating, cooperativity, induced fit, and conformational selection all from the same set of MISC data, detailing how SUB approaches the catalytic clefts and binds to the enzyme noncovalently before reacting to a trans-enamine. This was made possible in part by the application of singular value decomposition to the MISC data using a program that remains functional even if unit cell parameters change up to 3 Å during the reaction.
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Affiliation(s)
- Tek Narsingh Malla
- Physics Department, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Kara Zielinski
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA
| | - Luis Aldama
- Department of Biology, Northeastern Illinois University, Chicago, IL, USA
| | - Sasa Bajt
- The Hamburg Centre for Ultrafast Imaging, Hamburg, Germany
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen Synchrotron, Hamburg, Germany
| | - Denisse Feliz
- Department of Biology, Northeastern Illinois University, Chicago, IL, USA
| | - Brendon Hayes
- Linac Coherent Light Source LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Mark Hunter
- Linac Coherent Light Source LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Christopher Kupitz
- Linac Coherent Light Source LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Stella Lisova
- Linac Coherent Light Source LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Juraj Knoska
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen Synchrotron, Hamburg, Germany
| | - Jose Manuel Martin-Garcia
- Department of Crystallography and Structural Biology, Institute of Physical Chemistry Blas Cabrera, Spanish National Research Council (CSIC), Madrid, Spain
| | - Valerio Mariani
- Linac Coherent Light Source LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Suraj Pandey
- Physics Department, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Ishwor Poudyal
- Physics Department, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Raymond G Sierra
- Linac Coherent Light Source LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | | | - Oleksandr Yefanov
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen Synchrotron, Hamburg, Germany
| | - Chung Hong Yoon
- Linac Coherent Light Source LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Abbas Ourmazd
- Physics Department, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Petra Fromme
- School of Molecular Sciences and Biodesign Center for Applied Structural Discovery, 20 Arizona State University, Tempe, AZ, USA
| | - Peter Schwander
- Physics Department, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Anton Barty
- Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany
- Center for Data and Computing in Natural Science CDCS, Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany
| | - Henry N Chapman
- The Hamburg Centre for Ultrafast Imaging, Hamburg, Germany
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen Synchrotron, Hamburg, Germany
- Department of Physics, Universität Hamburg, Hamburg, Germany
| | - Emina A Stojkovic
- Department of Biology, Northeastern Illinois University, Chicago, IL, USA
| | - Alexander Batyuk
- Linac Coherent Light Source LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Sébastien Boutet
- Linac Coherent Light Source LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - George N Phillips
- Department of BioSciences, Rice University, Houston, TX, USA
- Department of Chemistry, Rice University, Houston, TX, USA
| | - Lois Pollack
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY, USA
| | - Marius Schmidt
- Physics Department, University of Wisconsin-Milwaukee, Milwaukee, WI, USA.
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9
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Chen Y, MacGilvary NJ, Tan S. Mycobacterium tuberculosis response to cholesterol is integrated with environmental pH and potassium levels via a lipid utilization regulator. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.22.554309. [PMID: 37662244 PMCID: PMC10473576 DOI: 10.1101/2023.08.22.554309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
How bacterial response to environmental cues and nutritional sources may be integrated in enabling host colonization is poorly understood. Exploiting a reporter-based screen, we discovered that overexpression of Mycobacterium tuberculosis (Mtb) lipid utilization regulators altered Mtb acidic pH response dampening by low environmental potassium (K+). Transcriptional analyses unveiled amplification of Mtb response to acidic pH in the presence of cholesterol, a major carbon source for Mtb during infection, and vice versa. Strikingly, deletion of the putative lipid regulator mce3R resulted in loss of augmentation of (i) cholesterol response at acidic pH, and (ii) low [K+] response by cholesterol, with minimal effect on Mtb response to each signal individually. Finally, the ∆mce3R mutant was attenuated for colonization in a murine model that recapitulates lesions with lipid-rich foamy macrophages. These findings reveal critical coordination between bacterial response to environmental and nutritional cues, and establish Mce3R as a crucial integrator of this process.
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Affiliation(s)
- Yue Chen
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
| | - Nathan J. MacGilvary
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
| | - Shumin Tan
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
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10
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Chen Y, Quirk NF, Tan S. Shining a light on bacterial environmental cue integration and its relation to metabolism. Mol Microbiol 2023; 120:71-74. [PMID: 37433048 PMCID: PMC10348474 DOI: 10.1111/mmi.15065] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 04/05/2023] [Accepted: 04/06/2023] [Indexed: 07/13/2023]
Abstract
The ability of a bacterium to successfully colonize its host is dependent on proper adaptation to its local environment. Environmental cues are diverse in nature, ranging from ions to bacterial-produced signals, and to host immune responses that can also be exploited by the bacteria as cues. Simultaneously, bacterial metabolism must be matched to the carbon and nitrogen sources available at a given time and location. While initial characterization of a bacterium's response to a given environmental cue or its ability to utilize a particular carbon/nitrogen source requires study of the signal in question in isolation, actual infection poses a situation where multiple signals are present concurrently. This perspective focuses on the untapped potential in uncovering and understanding how bacteria integrate their response to multiple concurrent environmental cues, and in elucidating the possible intrinsic coordination of bacterial environmental response with its metabolism.
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Affiliation(s)
- Yue Chen
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Natalia F. Quirk
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA
- Graduate Program in Molecular Microbiology, Graduate School of Biomedical Sciences, Tufts University, Boston, Massachusetts, USA
| | - Shumin Tan
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA
- Graduate Program in Molecular Microbiology, Graduate School of Biomedical Sciences, Tufts University, Boston, Massachusetts, USA
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11
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Sau S, Roy A, Agnivesh PK, Kumar S, Guru SK, Sharma S, Kalia NP. Unravelling the flexibility of Mycobacterium tuberculosis: an escape way for the bacilli. J Med Microbiol 2023; 72. [PMID: 37261969 DOI: 10.1099/jmm.0.001695] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023] Open
Abstract
The persistence of Mycobacterium tuberculosis makes it difficult to eradicate the associated infection from the host. The flexible nature of mycobacteria and their ability to adapt to adverse host conditions give rise to different drug-tolerant phenotypes. Granuloma formation restricts nutrient supply, limits oxygen availability and exposes bacteria to a low pH environment, resulting in non-replicating bacteria. These non-replicating mycobacteria, which need high doses and long exposure to anti-tubercular drugs, are the root cause of lengthy chemotherapy. Novel strategies, which are effective against non-replicating mycobacteria, need to be adopted to shorten tuberculosis treatment. This not only will reduce the treatment time but also will help prevent the emergence of multi-drug-resistant strains of mycobacteria.
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Affiliation(s)
- Shashikanta Sau
- Department of Biological Sciences (Pharmacology and Toxicology), National Institute of Pharmaceutical Education and Research, Hyderabad, Telangana, India
| | - Arnab Roy
- Department of Biological Sciences (Pharmacology and Toxicology), National Institute of Pharmaceutical Education and Research, Hyderabad, Telangana, India
| | - Puja Kumari Agnivesh
- Department of Biological Sciences (Pharmacology and Toxicology), National Institute of Pharmaceutical Education and Research, Hyderabad, Telangana, India
| | - Sunil Kumar
- Department of Biological Sciences (Pharmacology and Toxicology), National Institute of Pharmaceutical Education and Research, Hyderabad, Telangana, India
| | - Santosh Kumar Guru
- Department of Biological Sciences (Pharmacology and Toxicology), National Institute of Pharmaceutical Education and Research, Hyderabad, Telangana, India
| | - Sandeep Sharma
- Department of Medical Laboratory Sciences, Lovely Professional University, Phagwara, Punjab -144411, India
| | - Nitin Pal Kalia
- Department of Biological Sciences (Pharmacology and Toxicology), National Institute of Pharmaceutical Education and Research, Hyderabad, Telangana, India
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12
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Kalia NP, Singh S, Hards K, Cheung CY, Sviriaeva E, Banaei-Esfahani A, Aebersold R, Berney M, Cook GM, Pethe K. M. tuberculosis relies on trace oxygen to maintain energy homeostasis and survive in hypoxic environments. Cell Rep 2023; 42:112444. [PMID: 37115669 DOI: 10.1016/j.celrep.2023.112444] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 03/15/2023] [Accepted: 04/12/2023] [Indexed: 04/29/2023] Open
Abstract
The bioenergetic mechanisms by which Mycobacterium tuberculosis survives hypoxia are poorly understood. Current models assume that the bacterium shifts to an alternate electron acceptor or fermentation to maintain membrane potential and ATP synthesis. Counterintuitively, we find here that oxygen itself is the principal terminal electron acceptor during hypoxic dormancy. M. tuberculosis can metabolize oxygen efficiently at least two orders of magnitude below the concentration predicted to occur in hypoxic lung granulomas. Despite a difference in apparent affinity for oxygen, both the cytochrome bcc:aa3 and cytochrome bd oxidase respiratory branches are required for hypoxic respiration. Simultaneous inhibition of both oxidases blocks oxygen consumption, reduces ATP levels, and kills M. tuberculosis under hypoxia. The capacity of mycobacteria to scavenge trace levels of oxygen, coupled with the absence of complex regulatory mechanisms to achieve hierarchal control of the terminal oxidases, may be a key determinant of long-term M. tuberculosis survival in hypoxic lung granulomas.
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Affiliation(s)
- Nitin Pal Kalia
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 636921, Singapore; Department of Biological Sciences, National Institute of Pharmaceutical Education and Research (NIPER-H) Hyderabad, Hyderabad, Telangana 500037, India
| | - Samsher Singh
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 636921, Singapore
| | - Kiel Hards
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, Dunedin 9054, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland 92019, New Zealand
| | - Chen-Yi Cheung
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, Dunedin 9054, New Zealand
| | - Ekaterina Sviriaeva
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 636921, Singapore
| | - Amir Banaei-Esfahani
- Department of Biology, Institute of Molecular Systems Biology, ETH Zurich, 8057 Zurich, Switzerland
| | - Ruedi Aebersold
- Department of Biology, Institute of Molecular Systems Biology, ETH Zurich, 8057 Zurich, Switzerland; Faculty of Science, University of Zurich, 8057 Zurich, Switzerland
| | - Michael Berney
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Gregory M Cook
- Department of Microbiology and Immunology, School of Biomedical Sciences, University of Otago, Dunedin 9054, New Zealand; Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland 92019, New Zealand.
| | - Kevin Pethe
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 636921, Singapore; Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore 637551, Singapore; National Centre for Infectious Diseases, Singapore 308442, Singapore.
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13
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Haubenthal T, Hansen P, Krämer I, Gindt M, Jünger-Leif A, Utermöhlen O, Haas A. Specific preadaptations of Rhodococcus equi cooperate with its Virulence-associated protein A during macrophage infection. Mol Microbiol 2023; 119:285-301. [PMID: 36627747 DOI: 10.1111/mmi.15026] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 01/03/2023] [Accepted: 01/04/2023] [Indexed: 01/12/2023]
Abstract
Gram-positive Rhodococcus equi (Prescotella equi) is a lung pathogen of foals and immunocompromised humans. Intra-macrophage multiplication requires production of the bacterial Virulence-associated protein A (VapA) which is released into the phagosome lumen. VapA pH-neutralizes intracellular compartments allowing R. equi to multiply in an atypical macrophage phagolysosome. Here, we show that VapA does not support intra-macrophage growth of several other bacterial species demonstrating that only few bacteria have the specific preadaptations needed to profit from VapA. We show that the closest relative of R. equi, environmental Rhodococcus defluvii (Prescotella defluvii), does not multiply in macrophages at 37°C even when VapA is present because of its thermosensitivity but it does so once the infection temperature is lowered providing rare experimental evidence for 'thermal restriction'. Using growth experiments with isolated macrophage lysosomes and modified infection schemes we provide evidence that R. equi resists the attack by phagolysosome contents at low pH for several hours. During this time, R. equi produces and secretes VapA which enables it to grow at the expense of lysosome constituents. We present arguments that, under natural infection conditions, R. equi is VapA-less during the initial encounter with the host. This has important implications for vaccine development.
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Affiliation(s)
| | - Philipp Hansen
- Institute for Cell Biology, University of Bonn, Bonn, Germany
| | - Ina Krämer
- Institute for Cell Biology, University of Bonn, Bonn, Germany
| | - Mélanie Gindt
- Institute for Cell Biology, University of Bonn, Bonn, Germany
| | | | - Olaf Utermöhlen
- Institute for Medical Microbiology, Immunology and Hygiene, University of Cologne, Germany
| | - Albert Haas
- Institute for Cell Biology, University of Bonn, Bonn, Germany
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14
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Greenstein T, Aldridge BB. Tools to develop antibiotic combinations that target drug tolerance in Mycobacterium tuberculosis. Front Cell Infect Microbiol 2023; 12:1085946. [PMID: 36733851 PMCID: PMC9888313 DOI: 10.3389/fcimb.2022.1085946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 12/20/2022] [Indexed: 01/08/2023] Open
Abstract
Combination therapy is necessary to treat tuberculosis to decrease the rate of disease relapse and prevent the acquisition of drug resistance, and shorter regimens are urgently needed. The adaptation of Mycobacterium tuberculosis to various lesion microenvironments in infection induces various states of slow replication and non-replication and subsequent antibiotic tolerance. This non-heritable tolerance to treatment necessitates lengthy combination therapy. Therefore, it is critical to develop combination therapies that specifically target the different types of drug-tolerant cells in infection. As new tools to study drug combinations earlier in the drug development pipeline are being actively developed, we must consider how to best model the drug-tolerant cells to use these tools to design the best antibiotic combinations that target those cells and shorten tuberculosis therapy. In this review, we discuss the factors underlying types of drug tolerance, how combination therapy targets these populations of bacteria, and how drug tolerance is currently modeled for the development of tuberculosis multidrug therapy. We highlight areas for future studies to develop new tools that better model drug tolerance in tuberculosis infection specifically for combination therapy testing to bring the best drug regimens forward to the clinic.
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Affiliation(s)
- Talia Greenstein
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, United States
- Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, MA, United States
| | - Bree B Aldridge
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, United States
- Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, MA, United States
- Stuart B. Levy Center for Integrated Management of Antimicrobial Resistance, Boston, MA, United States
- Department of Biomedical Engineering, Tufts University School of Engineering, Medford, MA, United States
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15
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Aylan B, Botella L, Gutierrez MG, Santucci P. High content quantitative imaging of Mycobacterium tuberculosis responses to acidic microenvironments within human macrophages. FEBS Open Bio 2022. [PMID: 36520007 DOI: 10.1002/2211-5463.13537] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 11/30/2022] [Accepted: 12/04/2022] [Indexed: 12/23/2022] Open
Abstract
Intracellular pathogens such as Mycobacterium tuberculosis (Mtb) have evolved diverse strategies to counteract macrophage defence mechanisms including phagolysosomal biogenesis. Within macrophages, Mtb initially resides inside membrane-bound phagosomes that interact with lysosomes and become acidified. The ability of Mtb to control and subvert the fusion between phagosomes and lysosomes plays a key role in the pathogenesis of tuberculosis. Therefore, understanding how pathogens interact with the endolysosomal network and cope with intracellular acidification is important to better understand the disease. Here, we describe in detail the use of fluorescence microscopy-based approaches to investigate Mtb responses to acidic environments in cellulo. We report high-content imaging modalities to probe Mtb sensing of external pH or visualise in real-time Mtb intrabacterial pH within infected human macrophages. We discuss various methodologies with step-by-step analyses that enable robust image-based quantifications. Finally, we highlight the advantages and limitations of these different approaches and discuss potential alternatives that can be applied to further investigate Mtb-host cell interactions. These methods can be adapted to study host-pathogen interactions in different biological systems and experimental settings. Altogether, these approaches represent a valuable tool to further broaden our understanding of the cellular and molecular mechanisms underlying intracellular pathogen survival.
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Affiliation(s)
- Beren Aylan
- Host-Pathogen Interactions in Tuberculosis Laboratory, The Francis Crick Institute, London, UK
| | - Laure Botella
- Host-Pathogen Interactions in Tuberculosis Laboratory, The Francis Crick Institute, London, UK
| | - Maximiliano G Gutierrez
- Host-Pathogen Interactions in Tuberculosis Laboratory, The Francis Crick Institute, London, UK
| | - Pierre Santucci
- Host-Pathogen Interactions in Tuberculosis Laboratory, The Francis Crick Institute, London, UK
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16
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Dartois VA, Rubin EJ. Anti-tuberculosis treatment strategies and drug development: challenges and priorities. Nat Rev Microbiol 2022; 20:685-701. [PMID: 35478222 PMCID: PMC9045034 DOI: 10.1038/s41579-022-00731-y] [Citation(s) in RCA: 130] [Impact Index Per Article: 65.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/23/2022] [Indexed: 12/12/2022]
Abstract
Despite two decades of intensified research to understand and cure tuberculosis disease, biological uncertainties remain and hamper progress. However, owing to collaborative initiatives including academia, the pharmaceutical industry and non-for-profit organizations, the drug candidate pipeline is promising. This exceptional success comes with the inherent challenge of prioritizing multidrug regimens for clinical trials and revamping trial designs to accelerate regimen development and capitalize on drug discovery breakthroughs. Most wanted are markers of progression from latent infection to active pulmonary disease, markers of drug response and predictors of relapse, in vitro tools to uncover synergies that translate clinically and animal models to reliably assess the treatment shortening potential of new regimens. In this Review, we highlight the benefits and challenges of 'one-size-fits-all' regimens and treatment duration versus individualized therapy based on disease severity and host and pathogen characteristics, considering scientific and operational perspectives.
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Affiliation(s)
- Véronique A Dartois
- Center for Discovery and Innovation, and Hackensack Meridian School of Medicine, Department of Medical Sciences, Hackensack Meridian Health, Nutley, NJ, USA.
| | - Eric J Rubin
- Harvard T.H. Chan School of Public Health, Department of Immunology and Infectious Diseases, Boston, MA, USA
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17
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ppe51 Variants Enable Growth of Mycobacterium tuberculosis at Acidic pH by Selectively Promoting Glycerol Uptake. J Bacteriol 2022; 204:e0021222. [PMID: 36226966 PMCID: PMC9664963 DOI: 10.1128/jb.00212-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In defined media supplemented with single carbon sources, Mycobacterium tuberculosis (Mtb) exhibits carbon source specific growth restriction. When supplied with glycerol as the sole carbon source at pH 5.7, Mtb establishes a metabolically active state of nonreplicating persistence known as acid growth arrest. We hypothesized that acid growth arrest on glycerol is not a metabolic restriction, but rather an adaptive response. To test this hypothesis, we selected for and identified several Mtb mutants that could grow under these restrictive conditions. All mutations were mapped to the ppe51 gene and resulted in variants with 3 different amino acid substitutions- S211R, E215K, and A228D. Expression of the ppe51 variants in Mtb promoted growth at acidic pH showing that the mutant alleles are sufficient to cause the dominant gain-of-function, Enhanced Acid Growth (EAG) phenotype. Testing growth on other single carbon sources showed the PPE51 variants specifically enhanced growth on glycerol, suggesting PPE51 plays a role in glycerol uptake. Using radiolabeled glycerol, enhanced glycerol uptake was observed in Mtb expressing the PPE51 (S211R) variant, with glycerol overaccumulation in triacylglycerol. Notably, the EAG phenotype is deleterious for growth in macrophages, where the mutants have selectively faster replication and reduced survival in activated macrophages compared to resting macrophages. Recombinant PPE51 protein exhibited differential thermostability in the wild type (WT) or S211R variants in the presence of glycerol, supporting the model that EAG substitutions alter PPE51-glycerol interactions. Together, these findings support that PPE51 variants selectively promote glycerol uptake and that slowed growth at acidic pH is an important adaptive mechanism required for macrophage pathogenesis. IMPORTANCE It is puzzling why Mycobacterium tuberculosis (Mtb) cannot grow on glycerol at acidic pH, as it has a carbon source and oxygen, everything it needs to grow. In this study, we found that Mtb limits uptake of glycerol at acidic pH to restrict its growth and that mutations in ppe51 promote uptake of glycerol at acidic pH and enable growth. That is, Mtb can grow well at acidic pH on glycerol, but has adapted instead to stop growth. Notably, ppe51 variants exhibit enhanced replication and reduced survival in activated macrophages, supporting a role for pH-dependent slowed growth during macrophage pathogenesis.
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18
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Tomasi FG, Rubin EJ. Failing upwards: Genetics-based strategies to improve antibiotic discovery and efficacy in Mycobacterium tuberculosis. Front Cell Infect Microbiol 2022; 12:932556. [PMID: 36189351 PMCID: PMC9519881 DOI: 10.3389/fcimb.2022.932556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 08/17/2022] [Indexed: 11/18/2022] Open
Abstract
Therapeutic advances in the 20th century significantly reduced tuberculosis (TB) mortality. Nonetheless, TB still poses a massive global health challenge with significant annual morbidity and mortality that has been amplified during the COVID-19 pandemic. Unlike most common bacterial infectious diseases, successful TB treatment requires months-long regimens, which complicates the ability to treat all cases quickly and effectively. Improving TB chemotherapy by reducing treatment duration and optimizing combinations of drugs is an important step to reducing relapse. In this review, we outline the limitations of current multidrug regimens against TB and have reviewed the genetic tools available to improve the identification of drug targets. The rational design of regimens that sterilize diverse phenotypic subpopulations will maximize bacterial killing while minimizing both treatment duration and infection relapse. Importantly, the TB field currently has all the necessary genetic and analytical tools to screen for and prioritize drug targets in vitro based on the vulnerability of essential and non-essential genes in the Mtb genome and to translate these findings in in vivo models. Combining genetic methods with chemical screens offers a formidable strategy to redefine the preclinical design of TB therapy by identifying powerful new targets altogether, as well as targets that lend new efficacy to existing drugs.
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19
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Giacalone D, Yap RE, Ecker AMV, Tan S. PrrA modulates Mycobacterium tuberculosis response to multiple environmental cues and is critically regulated by serine/threonine protein kinases. PLoS Genet 2022; 18:e1010331. [PMID: 35913986 PMCID: PMC9371303 DOI: 10.1371/journal.pgen.1010331] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 08/11/2022] [Accepted: 07/08/2022] [Indexed: 12/04/2022] Open
Abstract
The ability of Mycobacterium tuberculosis (Mtb) to adapt to its surrounding environment is critical for the bacterium to successfully colonize its host. Transcriptional changes are a vital mechanism by which Mtb responds to key environmental signals experienced, such as pH, chloride (Cl-), nitric oxide (NO), and hypoxia. However, much remains unknown regarding how Mtb coordinates its response to the disparate signals seen during infection. Utilizing a transcription factor (TF) overexpression plasmid library in combination with a pH/Cl--responsive luciferase reporter, we identified the essential TF, PrrA, part of the PrrAB two-component system, as a TF involved in modulation of Mtb response to pH and Cl-. Further studies revealed that PrrA also affected Mtb response to NO and hypoxia, with prrA overexpression dampening induction of NO and hypoxia-responsive genes. PrrA is phosphorylated not just by its cognate sensor histidine kinase PrrB, but also by serine/threonine protein kinases (STPKs) at a second distinct site. Strikingly, a STPK-phosphoablative PrrA variant was significantly dampened in its response to NO versus wild type Mtb, disrupted in its ability to adaptively enter a non-replicative state upon extended NO exposure, and attenuated for in vivo colonization. Together, our results reveal PrrA as an important regulator of Mtb response to multiple environmental signals, and uncover a critical role of STPK regulation of PrrA in its function. Vital to successful host colonization by Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, is the bacterium’s ability to respond and adapt to changes in its local environment during infection. Here, we discover that the essential transcription factor PrrA, part of the PrrAB two-component system (TCS), modulates Mtb response to four important environmental cues encountered within the host: pH, chloride, nitric oxide, and hypoxia. PrrA acts as a rheostat, adjusting the amplitude of Mtb gene expression changes upon bacterial exposure to each of the four environmental signals. Further, we reveal a critical impact of serine/threonine protein kinases (STPKs) on PrrA function, with prevention of STPK phosphorylation of PrrA disrupting adaptive response of Mtb to growth-inhibiting cues and attenuating the bacterium’s ability to colonize its host. Our work uncovers PrrA as a regulator with broad impact across environmental signals, and highlights how two regulatory systems, TCSs and STPKs, critically interact in coordinating Mtb response to environmental cues.
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Affiliation(s)
- David Giacalone
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
- Graduate Program in Molecular Microbiology, Graduate School of Biomedical Sciences, Tufts University, Boston, Massachusetts, United States of America
| | - Rochelle E. Yap
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - Alwyn M. V. Ecker
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
| | - Shumin Tan
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
- Graduate Program in Molecular Microbiology, Graduate School of Biomedical Sciences, Tufts University, Boston, Massachusetts, United States of America
- * E-mail:
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20
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Ma R, Farrell D, Gonzalez G, Browne JA, Nakajima C, Suzuki Y, Gordon SV. The TbD1 Locus Mediates a Hypoxia-Induced Copper Response in Mycobacterium bovis. Front Microbiol 2022; 13:817952. [PMID: 35495699 PMCID: PMC9048740 DOI: 10.3389/fmicb.2022.817952] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 02/10/2022] [Indexed: 12/12/2022] Open
Abstract
The Mycobacterium tuberculosis complex (MTBC) contains the causative agents of tuberculosis (TB) in mammals. The archetypal members of the MTBC, Mycobacterium tuberculosis and Mycobacterium bovis, cause human tuberculosis and bovine tuberculosis, respectively. Although M. tuberculosis and M. bovis share over 99.9% genome identity, they show distinct host adaptation for humans and animals; hence, while the molecular basis of host adaptation is encoded in their genomes, the mechanistic basis of host tropism is still unclear. Exploration of the in vitro phenotypic consequences of known genetic difference between M. bovis and M. tuberculosis offers one route to explore genotype–phenotype links that may play a role in host adaptation. The TbD1 (“Mycobacterium tuberculosis deletion 1 region”) locus encompasses the mmpS6 and mmpL6 genes. TbD1 is absent in M. tuberculosis “modern” lineages (Lineages 2, 3, and 4) but present in “ancestral” M. tuberculosis (Lineages 1 and 7), Mycobacterium africanum lineages (Lineages 5 and 6), newly identified M. tuberculosis lineages (Lineages 8 and 9), and animal adapted strains, such as M. bovis. The function of TbD1 has previously been investigated in M. tuberculosis, where conflicting data has emerged on the role of TbD1 in sensitivity to oxidative stress, while the underlying mechanistic basis of such a phenotype is unclear. In this study, we aimed to shed further light on the role of the TbD1 locus by exploring its function in M. bovis. Toward this, we constructed an M. bovis TbD1 knockout (ΔTbD1) strain and conducted comparative transcriptomics to define global gene expression profiles of M. bovis wild-type (WT) and the ΔTbD1 strains under in vitro culture conditions (rolling and standing cultures). This analysis revealed differential induction of a hypoxia-driven copper response in WT and ΔTbD1 strains. In vitro phenotypic assays demonstrated that the deletion of TbD1 sensitized M. bovis to H2O2 and hypoxia-specific copper toxicity. Our study provides new information on the function of the TbD1 locus in M. bovis and its role in stress responses in the MTBC.
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Affiliation(s)
- Ruoyao Ma
- UCD School of Veterinary Medicine, University College Dublin, Dublin, Ireland
| | - Damien Farrell
- UCD School of Veterinary Medicine, University College Dublin, Dublin, Ireland
| | - Gabriel Gonzalez
- Hokkaido University International Institute for Zoonosis Control, Sapporo, Japan
| | - John A. Browne
- UCD School of Agriculture and Food Science, University College Dublin, Dublin, Ireland
| | - Chie Nakajima
- Hokkaido University International Institute for Zoonosis Control, Sapporo, Japan
- Division of Bioresources, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Yasuhiko Suzuki
- Hokkaido University International Institute for Zoonosis Control, Sapporo, Japan
- Division of Bioresources, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Stephen V. Gordon
- UCD School of Veterinary Medicine, University College Dublin, Dublin, Ireland
- Hokkaido University International Institute for Zoonosis Control, Sapporo, Japan
- UCD Conway Institute, University College Dublin, Dublin, Ireland
- *Correspondence: Stephen V. Gordon,
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21
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Boldrin F, Cioetto Mazzabò L, Lanéelle MA, Rindi L, Segafreddo G, Lemassu A, Etienne G, Conflitti M, Daffé M, Garzino Demo A, Manganelli R, Marrakchi H, Provvedi R. LysX2 is a Mycobacterium tuberculosis membrane protein with an extracytoplasmic MprF-like domain. BMC Microbiol 2022; 22:85. [PMID: 35365094 PMCID: PMC8974105 DOI: 10.1186/s12866-022-02493-2] [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: 09/29/2021] [Accepted: 03/11/2022] [Indexed: 11/17/2022] Open
Abstract
Background Aminoacyl-phosphatidylglycerol (aaPG) synthases are bacterial enzymes that usually catalyze transfer of aminoacyl residues to the plasma membrane phospholipid phosphatidylglycerol (PG). The result is introduction of positive charges onto the cytoplasmic membrane, yielding reduced affinity towards cationic antimicrobial peptides, and increased resistance to acidic environments. Therefore, these enzymes represent an important defense mechanism for many pathogens, including Staphylococcus aureus and Mycobacterium tuberculosis (Mtb), which are known to encode for lysyl-(Lys)-PG synthase MprF and LysX, respectively. Here, we used a combination of bioinformatic, genetic and bacteriological methods to characterize a protein encoded by the Mtb genome, Rv1619, carrying a domain with high similarity to MprF-like domains, suggesting that this protein could be a new aaPG synthase family member. However, unlike homologous domains of MprF and LysX that are positioned in the cytoplasm, we predicted that the MprF-like domain in LysX2 is in the extracytoplasmic region. Results Using genetic fusions to the Escherichia coli proteins PhoA and LacZ of LysX2, we confirmed this unique membrane topology, as well as LysX and MprF as benchmarks. Expression of lysX2 in Mycobacterium smegmatis increased cell resistance to human β-defensin 2 and sodium nitrite, enhanced cell viability and delayed biofilm formation in acidic pH environment. Remarkably, MtLysX2 significantly reduced the negative charge on the bacterial surface upon exposure to an acidic environment. Additionally, we found LysX2 orthologues in major human pathogens and in rapid-growing mycobacteria frequently associated with human infections, but not in environmental and non-pathogenic mycobacteria. Conclusions Overall, our data suggest that LysX2 is a prototype of a new class within the MprF-like protein family that likely enhances survival of the pathogenic species through its catalytic domain which is exposed to the extracytoplasmic side of the cell membrane and is required to decrease the negative charge on the bacterial surface through a yet uncharacterized mechanism. Supplementary Information The online version contains supplementary material available at 10.1186/s12866-022-02493-2.
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Affiliation(s)
| | | | - Marie-Antoinette Lanéelle
- Institut de Pharmacologie et de Biologie Structurale, IPBS, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Laura Rindi
- Department of Translational Research, University of Pisa, Pisa, Italy
| | - Greta Segafreddo
- Department of Molecular Medicine, University of Padua, Padua, Italy
| | - Anne Lemassu
- Institut de Pharmacologie et de Biologie Structurale, IPBS, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Gilles Etienne
- Institut de Pharmacologie et de Biologie Structurale, IPBS, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Marta Conflitti
- Department of Molecular Medicine, University of Padua, Padua, Italy
| | - Mamadou Daffé
- Institut de Pharmacologie et de Biologie Structurale, IPBS, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Alfredo Garzino Demo
- Department of Molecular Medicine, University of Padua, Padua, Italy.,Department of Microbiology and Immunology, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | | | - Hedia Marrakchi
- Institut de Pharmacologie et de Biologie Structurale, IPBS, Université de Toulouse, CNRS, UPS, Toulouse, France
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22
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Chung ES, Johnson WC, Aldridge BB. Types and functions of heterogeneity in mycobacteria. Nat Rev Microbiol 2022; 20:529-541. [PMID: 35365812 DOI: 10.1038/s41579-022-00721-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/01/2022] [Indexed: 12/24/2022]
Abstract
The remarkable ability of Mycobacterium tuberculosis to survive attacks from the host immune response and drug treatment is due to the resilience of a few bacilli rather than a result of survival of the entire population. Maintenance of mycobacterial subpopulations with distinct phenotypic characteristics is key for survival in the face of dynamic and variable stressors encountered during infection. Mycobacterial populations develop a wide range of phenotypes through an innate asymmetric growth pattern and adaptation to fluctuating microenvironments during infection that point to heterogeneity being a vital survival strategy. In this Review, we describe different types of mycobacterial heterogeneity and discuss how heterogeneity is generated and regulated in response to environmental cues. We discuss how this heterogeneity may have a key role in recording memory of their environment at both the single-cell level and the population level to give mycobacterial populations plasticity to withstand complex stressors.
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Affiliation(s)
- Eun Seon Chung
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, USA
| | - William C Johnson
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, USA.,Tufts University School of Graduate Biomedical Sciences, Boston, MA, USA
| | - Bree B Aldridge
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, USA. .,Tufts University School of Graduate Biomedical Sciences, Boston, MA, USA. .,Stuart B. Levy Center for Integrated Management of Antimicrobial Resistance, Tufts University, Boston, MA, USA. .,Department of Biomedical Engineering, Tufts University School of Engineering, Medford, MA, USA.
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23
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Kevorkian YL, MacGilvary NJ, Giacalone D, Johnson C, Tan S. Rv0500A is a transcription factor that links Mycobacterium tuberculosis environmental response with division and impacts host colonization. Mol Microbiol 2022; 117:1048-1062. [PMID: 35167150 PMCID: PMC9382876 DOI: 10.1111/mmi.14886] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Revised: 01/29/2022] [Accepted: 02/10/2022] [Indexed: 11/28/2022]
Abstract
For Mycobacterium tuberculosis (Mtb) to successfully infect a host, it must be able to adapt to changes in its microenvironment, including to variations in ionic signals such as pH and chloride (Cl- ), and link these responses to its growth. Transcriptional changes are a key mechanism for Mtb environmental adaptation, and we identify here Rv0500A as a novel transcriptional regulator that links Mtb environmental response and division processes. Global transcriptional profiling revealed that Rv0500A acts as a repressor and influences the expression of genes related to division, with the magnitude of its effect modulated by pH and Cl- . Rv0500A can directly bind the promoters of several of these target genes, and we identify key residues required for its DNA-binding ability and biological effect. Overexpression of rv0500A disrupted Mtb growth morphology, resulting in filamentation that was exacerbated by high environmental Cl- levels and acidic pH. Finally, we show that perturbation of rv0500A leads to attenuation of the ability of Mtb to colonize its host in vivo. Our work highlights the important link between Mtb environmental response and growth characteristics, and uncovers a new transcription factor involved in this critical facet of Mtb biology.
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Affiliation(s)
- Yuzo L Kevorkian
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA.,Graduate Program in Molecular Microbiology, Graduate School of Biomedical Sciences, Tufts University, Boston, Massachusetts, USA
| | - Nathan J MacGilvary
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - David Giacalone
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA.,Graduate Program in Molecular Microbiology, Graduate School of Biomedical Sciences, Tufts University, Boston, Massachusetts, USA
| | - Calvin Johnson
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Shumin Tan
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA.,Graduate Program in Molecular Microbiology, Graduate School of Biomedical Sciences, Tufts University, Boston, Massachusetts, USA
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24
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Apiyo D, Mouton JM, Louw C, Sampson SL, Louw TM. Dynamic mathematical model development and validation of in vitro Mycobacterium smegmatis growth under nutrient- and pH-stress. J Theor Biol 2022; 532:110921. [PMID: 34582827 DOI: 10.1016/j.jtbi.2021.110921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/27/2021] [Accepted: 09/21/2021] [Indexed: 10/20/2022]
Abstract
Mycobacterium tuberculosis can exist within a host for lengthy periods, tolerating even antibiotic challenge. This non-heritable, antibiotic tolerant "persister" state, is thought to underlie latent Tuberculosis (TB) infection and a deeper understanding thereof could inform treatment strategies. In addition to experimental studies, mathematical and computational modelling approaches are widely employed to study persistence from both an in vivo and in vitro perspective. However, specialized models (partial differential equations, agent-based, multiscale, etc.) rely on several difficult to determine parameters. In this study, a dynamic mathematical model was developed to predict the response of Mycobacterium smegmatis (a model organism for M. tuberculosis) grown in batch culture and subjected to a range of in vitro environmental stresses. Lag phase dynamics, pH variations and internal nitrogen storage were mechanistically modelled. Experimental results were used to train model parameters using global optimization, with extensive subsequent model validation to ensure extensibility to more complex modelling frameworks. This included an identifiability analysis which indicated that seven of the thirteen model parameters were uniquely identifiable. Non-identifiable parameters were critically evaluated. Model predictions compared to validation data (based on experimental results not used during training) were accurate with less than 16% maximum absolute percentage error, indicating that the model is accurate even when extrapolating to new experimental conditions. The bulk growth model can be extended to spatially heterogeneous simulations such as an agent-based model to simulate in vitro granuloma models or, eventually, in vivo conditions, where distributed environmental conditions are difficult to measure.
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Affiliation(s)
- D Apiyo
- Department of Process Engineering, Faculty of Engineering, Stellenbosch University, Stellenbosch, South Africa
| | - J M Mouton
- Department of Science and Innovation/National Research Foundation (DSI/NRF) Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - C Louw
- Department of Process Engineering, Faculty of Engineering, Stellenbosch University, Stellenbosch, South Africa
| | - S L Sampson
- Department of Science and Innovation/National Research Foundation (DSI/NRF) Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - T M Louw
- Department of Process Engineering, Faculty of Engineering, Stellenbosch University, Stellenbosch, South Africa.
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Perveen S, Sharma R. Screening approaches and therapeutic targets: The two driving wheels of tuberculosis drug discovery. Biochem Pharmacol 2022; 197:114906. [PMID: 34990594 DOI: 10.1016/j.bcp.2021.114906] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 12/28/2021] [Accepted: 12/28/2021] [Indexed: 12/21/2022]
Abstract
Tuberculosis (TB) is an infectious disease, infecting a quarter of world's population. Drug resistant TB further exacerbates the grim scenario of the drying TB drug discovery pipeline. The limited arsenal to fight TB presses the need for thorough efforts for identifying promising hits to combat the disease. The review highlights the efforts in the field of tuberculosis drug discovery, with an emphasis on massive drug screening campaigns for identifying novel hits against Mtb in both industry and academia. As an intracellular pathogen, mycobacteria reside in a complicated intracellular environment with multiple factors at play. Here, we outline various strategies employed in an effort to mimic the intracellular milieu for bringing the screening models closer to the actual settings. The review also focuses on the novel targets and pathways that could aid in target-based drug discovery in TB. The recent high throughput screening efforts resulting in the identification of potent hits against Mtb has been summarized in this article. There is a pressing need for effective screening strategies and approaches employing innovative tools and recent technologies; including nanotechnology, gene-editing tools such as CRISPR-cas system, host-directed bacterial killing and high content screening to augment the TB drug discovery pipeline with safer and shorter drug regimens.
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Affiliation(s)
- Summaya Perveen
- Infectious Diseases Division, CSIR- Indian Institute of Integrative Medicine, Jammu 180001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Rashmi Sharma
- Infectious Diseases Division, CSIR- Indian Institute of Integrative Medicine, Jammu 180001, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
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26
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Mycobacterial MCE proteins as transporters that control lipid homeostasis of the cell wall. Tuberculosis (Edinb) 2021; 132:102162. [PMID: 34952299 DOI: 10.1016/j.tube.2021.102162] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 11/30/2021] [Accepted: 12/10/2021] [Indexed: 01/05/2023]
Abstract
Mammalian cell entry (mce) genes are not only present in genomes of pathogenic mycobacteria, including Mycobacterium tuberculosis (the causative agent of tuberculosis), but also in saprophytic and opportunistic mycobacterial species. MCE are conserved cell-wall proteins encoded by mce operons, which maintain an identical structure in all mycobacteria: two yrbE genes (A and B) followed by six mce genes (A, B, C, D, E and F). Although these proteins are known to participate in the virulence of pathogenic mycobacteria, the presence of the operons in nonpathogenic mycobacteria and other bacteria indicates that they play another role apart from host cell invasion. In this respect, more recent studies suggest that they are functionally similar to ABC transporters and form part of lipid transporters in Actinobacteria. To date, most reviews on mce operons in the literature discuss their role in virulence. However, according to data from transcriptional studies, mce genes, particularly the mce1 and mce4 operons, modify their expression according to the carbon source and upon hypoxia, starvation, surface stress and oxidative stress; which suggests a role of MCE proteins in the response of Mycobacteria to external stressors. In addition to these data, this review also summarizes the studies demonstrating the role of MCE proteins as lipid transporters as well as the relevance of their transport function in the interaction of pathogenic Mycobacteria with the hosts. Altogether, the evidence to date would indicate that MCE proteins participate in the response to the stress conditions that mycobacteria encounter during infection, by participating in the cell wall remodelling and possibly contributing to lipid homeostasis.
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27
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Beites T, Jansen RS, Wang R, Jinich A, Rhee KY, Schnappinger D, Ehrt S. Multiple acyl-CoA dehydrogenase deficiency kills Mycobacterium tuberculosis in vitro and during infection. Nat Commun 2021; 12:6593. [PMID: 34782606 PMCID: PMC8593149 DOI: 10.1038/s41467-021-26941-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 10/26/2021] [Indexed: 11/14/2022] Open
Abstract
The human pathogen Mycobacterium tuberculosis depends on host fatty acids as a carbon source. However, fatty acid β-oxidation is mediated by redundant enzymes, which hampers the development of antitubercular drugs targeting this pathway. Here, we show that rv0338c, which we refer to as etfD, encodes a membrane oxidoreductase essential for β-oxidation in M. tuberculosis. An etfD deletion mutant is incapable of growing on fatty acids or cholesterol, with long-chain fatty acids being bactericidal, and fails to grow and survive in mice. Analysis of the mutant’s metabolome reveals a block in β-oxidation at the step catalyzed by acyl-CoA dehydrogenases (ACADs), which in other organisms are functionally dependent on an electron transfer flavoprotein (ETF) and its cognate oxidoreductase. We use immunoprecipitation to show that M. tuberculosis EtfD interacts with FixA (EtfB), a protein that is homologous to the human ETF subunit β and is encoded in an operon with fixB, encoding a homologue of human ETF subunit α. We thus refer to FixA and FixB as EtfB and EtfA, respectively. Our results indicate that EtfBA and EtfD (which is not homologous to human EtfD) function as the ETF and oxidoreductase for β-oxidation in M. tuberculosis and support this pathway as a potential target for tuberculosis drug development. The pathogen Mycobacterium tuberculosis depends on host fatty acids and cholesterol as carbon sources. Here, Beites et al. identify a protein complex that is essential for fatty acid and cholesterol utilization and thus for survival of M. tuberculosis during infection, supporting this pathway as a potential target for tuberculosis drug development.
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Affiliation(s)
- Tiago Beites
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, NY, 10065, USA
| | - Robert S Jansen
- Division of Infectious Diseases, Department of Medicine, Weill Cornell Medical College, New York, NY, 10065, USA.,Department of Microbiology, Radboud University, 6525 AJ, Nijmegen, The Netherlands
| | - Ruojun Wang
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, NY, 10065, USA.,Department of Molecular Biology, Princeton University, Princeton, NJ, 08540, USA
| | - Adrian Jinich
- Division of Infectious Diseases, Department of Medicine, Weill Cornell Medical College, New York, NY, 10065, USA
| | - Kyu Y Rhee
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, NY, 10065, USA.,Division of Infectious Diseases, Department of Medicine, Weill Cornell Medical College, New York, NY, 10065, USA
| | - Dirk Schnappinger
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, NY, 10065, USA
| | - Sabine Ehrt
- Department of Microbiology and Immunology, Weill Cornell Medical College, New York, NY, 10065, USA.
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