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Xu M, Liu M, Liu T, Pan X, Ren Q, Han T, Gou L. HigA2 (Rv2021c) Is a Transcriptional Regulator with Multiple Regulatory Targets in Mycobacterium tuberculosis. Microorganisms 2024; 12:1244. [PMID: 38930627 PMCID: PMC11205783 DOI: 10.3390/microorganisms12061244] [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: 05/25/2024] [Revised: 06/17/2024] [Accepted: 06/18/2024] [Indexed: 06/28/2024] Open
Abstract
Toxin-antitoxin (TA) systems are the major mechanism for persister formation in Mycobacterium tuberculosis (Mtb). Previous studies found that HigBA2 (Rv2022c-Rv2021c), a predicted type II TA system of Mtb, could be activated for transcription in response to multiple stresses such as anti-tuberculosis drugs, nutrient starvation, endure hypoxia, acidic pH, etc. In this study, we determined the binding site of HigA2 (Rv2021c), which is located in the coding region of the upstream gene higB2 (Rv2022c), and the conserved recognition motif of HigA2 was characterized via oligonucleotide mutation. Eight binding sites of HigA2 were further found in the Mtb genome according to the conserved motif. RT-PCR showed that HigA2 can regulate the transcription level of all eight of these genes and three adjacent downstream genes. DNA pull-down experiments showed that twelve functional regulators sense external regulatory signals and may regulate the transcription of the HigBA2 system. Of these, Rv0903c, Rv0744c, Rv0474, Rv3124, Rv2603c, and Rv3583c may be involved in the regulation of external stress signals. In general, we identified the downstream target genes and possible upstream regulatory genes of HigA2, which paved the way for the illustration of the persistence establishment mechanism in Mtb.
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Affiliation(s)
- Mingyan Xu
- Hebei Province Key Laboratory of Occupational Health and Safety for Coal Industry, School of Public Health, North China University of Science and Technology, Tangshan 063210, China; (M.X.); (M.L.); (T.L.); (X.P.); (Q.R.)
| | - Meikun Liu
- Hebei Province Key Laboratory of Occupational Health and Safety for Coal Industry, School of Public Health, North China University of Science and Technology, Tangshan 063210, China; (M.X.); (M.L.); (T.L.); (X.P.); (Q.R.)
| | - Tong Liu
- Hebei Province Key Laboratory of Occupational Health and Safety for Coal Industry, School of Public Health, North China University of Science and Technology, Tangshan 063210, China; (M.X.); (M.L.); (T.L.); (X.P.); (Q.R.)
| | - Xuemei Pan
- Hebei Province Key Laboratory of Occupational Health and Safety for Coal Industry, School of Public Health, North China University of Science and Technology, Tangshan 063210, China; (M.X.); (M.L.); (T.L.); (X.P.); (Q.R.)
| | - Qi Ren
- Hebei Province Key Laboratory of Occupational Health and Safety for Coal Industry, School of Public Health, North China University of Science and Technology, Tangshan 063210, China; (M.X.); (M.L.); (T.L.); (X.P.); (Q.R.)
| | - Tiesheng Han
- Hebei Province Key Laboratory of Occupational Health and Safety for Coal Industry, School of Public Health, North China University of Science and Technology, Tangshan 063210, China; (M.X.); (M.L.); (T.L.); (X.P.); (Q.R.)
| | - Lixia Gou
- School of Life Science, North China University of Science and Technology, Tangshan 063210, China
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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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3
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Kathayat D, VanderVen BC. Exploiting cAMP signaling in Mycobacterium tuberculosis for drug discovery. Trends Microbiol 2024:S0966-842X(24)00008-8. [PMID: 38360432 DOI: 10.1016/j.tim.2024.01.008] [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: 12/20/2023] [Revised: 01/21/2024] [Accepted: 01/23/2024] [Indexed: 02/17/2024]
Abstract
Mycobacterium tuberculosis (Mtb) replicates within host macrophages by adapting to the stressful and nutritionally constrained environments in these cells. Exploiting these adaptations for drug discovery has revealed that perturbing cAMP signaling can restrict Mtb growth in macrophages. Specifically, compounds that agonize or stimulate the bacterial enzyme, Rv1625c/Cya, induce cAMP synthesis and this interferes with the ability of Mtb to metabolize cholesterol. In murine tuberculosis (TB) infection models, Rv1625c/Cya agonists contribute to reducing relapse and shortening combination treatments, highlighting the therapeutic potential for this class of compounds. More recently, cAMP signaling has been implicated in regulating fatty acid utilization by Mtb. Thus, a new model is beginning to emerge in which cAMP regulates the utilization of host lipids by Mtb during infection, and this could provide new targets for TB drug development. Here, we summarize the current understanding of cAMP signaling in Mtb with a focus on our understanding of how cAMP signaling impacts Mtb physiology during infection. We also discuss additional cAMP-related drug targets in Mtb and other bacterial pathogens that may have therapeutic potential.
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Affiliation(s)
- Dipak Kathayat
- Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA
| | - Brian C VanderVen
- Microbiology and Immunology, Cornell University, Ithaca, NY 14853, USA.
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4
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Chaiyachat P, Kaewseekhao B, Chaiprasert A, Kamolwat P, Nonghanphithak D, Phetcharaburanin J, Sirichoat A, Ong RTH, Faksri K. Metabolomic analysis of Mycobacterium tuberculosis reveals metabolic profiles for identification of drug-resistant tuberculosis. Sci Rep 2023; 13:8655. [PMID: 37244948 DOI: 10.1038/s41598-023-35882-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 05/25/2023] [Indexed: 05/29/2023] Open
Abstract
The detection of pre-extensively (pre-XDR) and extensively drug-resistant tuberculosis (XDR-TB) is challenging. Drug-susceptibility tests for some anti-TB drugs, especially ethambutol (ETH) and ethionamide (ETO), are problematic due to overlapping thresholds to differentiate between susceptible and resistant phenotypes. We aimed to identify possible metabolomic markers to detect Mycobacterium tuberculosis (Mtb) strains causing pre-XDR and XDR-TB. The metabolic patterns of ETH- and ETO-resistant Mtb isolates were also investigated. Metabolomics of 150 Mtb isolates (54 pre-XDR, 63 XDR-TB and 33 pan-susceptible; pan-S) were investigated. Metabolomics of ETH and ETO phenotypically resistant subgroups were analyzed using UHPLC-ESI-QTOF-MS/MS. Orthogonal partial least-squares discriminant analysis revealed distinct separation in all pairwise comparisons among groups. Two metabolites (meso-hydroxyheme and itaconic anhydride) were able to differentiate the pre-XDR and XDR-TB groups from the pan-S group with 100% sensitivity and 100% specificity. In comparisons of the ETH and ETO phenotypically resistant subsets, sets of increased (ETH = 15, ETO = 7) and decreased (ETH = 1, ETO = 6) metabolites specific for the resistance phenotype of each drug were found. We demonstrated the potential for metabolomics of Mtb to differentiate among types of DR-TB as well as between isolates that were phenotypically resistant to ETO and ETH. Thus, metabolomics might be further applied for DR-TB diagnosis and patient management.
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Affiliation(s)
- Pratchakan Chaiyachat
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Research and Diagnostic Center for Emerging Infectious Diseases (RCEID), Khon Kaen University, Khon Kaen, Thailand
| | - Benjawan Kaewseekhao
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Research and Diagnostic Center for Emerging Infectious Diseases (RCEID), Khon Kaen University, Khon Kaen, Thailand
| | - Angkana Chaiprasert
- Office for Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Phalin Kamolwat
- Bureau of Tuberculosis, Department of Disease Control, Ministry of Public Health, Nonthaburi, Thailand
| | - Ditthawat Nonghanphithak
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Research and Diagnostic Center for Emerging Infectious Diseases (RCEID), Khon Kaen University, Khon Kaen, Thailand
| | - Jutarop Phetcharaburanin
- Department of Systems Biosciences and Computational Medicine, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Auttawit Sirichoat
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
- Research and Diagnostic Center for Emerging Infectious Diseases (RCEID), Khon Kaen University, Khon Kaen, Thailand
| | - Rick Twee-Hee Ong
- Saw Swee Hock School of Public Health, National University of Singapore and National University Health System, Singapore, Singapore
| | - Kiatichai Faksri
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.
- Research and Diagnostic Center for Emerging Infectious Diseases (RCEID), Khon Kaen University, Khon Kaen, Thailand.
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McDowell JR, Bai G, Lasek-Nesselquist E, Eisele LE, Wu Y, Hurteau G, Johnson R, Bai Y, Chen Y, Chan J, McDonough KA. Mycobacterial phosphodiesterase Rv0805 is a virulence determinant and its cyclic nucleotide hydrolytic activity is required for propionate detoxification. Mol Microbiol 2023; 119:401-422. [PMID: 36760076 PMCID: PMC10315211 DOI: 10.1111/mmi.15030] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 01/15/2023] [Accepted: 01/21/2023] [Indexed: 02/11/2023]
Abstract
Cyclic AMP (cAMP) signaling is essential to Mycobacterium tuberculosis (Mtb) pathogenesis. However, the roles of phosphodiesterases (PDEs) Rv0805, and the recently identified Rv1339, in cAMP homeostasis and Mtb biology are unclear. We found that Rv0805 modulates Mtb growth within mice, macrophages and on host-associated carbon sources. Mycobacterium bovis BCG grown on a combination of propionate and glycerol as carbon sources showed high levels of cAMP and had a strict requirement for Rv0805 cNMP hydrolytic activity. Supplementation with vitamin B12 or spontaneous genetic mutations in the pta-ackA operon restored the growth of BCGΔRv0805 and eliminated propionate-associated cAMP increases. Surprisingly, reduction of total cAMP levels by ectopic expression of Rv1339 restored only 20% of growth, while Rv0805 complementation fully restored growth despite a smaller effect on total cAMP levels. Deletion of an Rv0805 localization domain also reduced BCG growth in the presence of propionate and glycerol. We propose that localized Rv0805 cAMP hydrolysis modulates activity of a specialized pathway associated with propionate metabolism, while Rv1339 has a broader role in cAMP homeostasis. Future studies will address the biological roles of Rv0805 and Rv1339, including their impacts on metabolism, cAMP signaling and Mtb pathogenesis.
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Affiliation(s)
- James R. McDowell
- Wadsworth Center, New York State Department of Health, Albany, NY 12208
- Department of Biomedical Sciences, School of Public Health, University at Albany, SUNY, Albany NY 12208
| | - Guangchun Bai
- Wadsworth Center, New York State Department of Health, Albany, NY 12208
- Department of Immunology and Microbial Disease, MC-151, Albany Medical College, Albany, NY 12208-3479
| | - Erica Lasek-Nesselquist
- Wadsworth Center, New York State Department of Health, Albany, NY 12208
- Department of Biomedical Sciences, School of Public Health, University at Albany, SUNY, Albany NY 12208
| | - Leslie E. Eisele
- Wadsworth Center, New York State Department of Health, Albany, NY 12208
| | - Yan Wu
- Wadsworth Center, New York State Department of Health, Albany, NY 12208
| | - Gregory Hurteau
- Wadsworth Center, New York State Department of Health, Albany, NY 12208
| | - Richard Johnson
- Wadsworth Center, New York State Department of Health, Albany, NY 12208
- Department of Biomedical Sciences, School of Public Health, University at Albany, SUNY, Albany NY 12208
| | - Yinlan Bai
- Department of Biomedical Sciences, School of Public Health, University at Albany, SUNY, Albany NY 12208
| | - Yong Chen
- Albert Einstein College of Medicine, Bronx, NY
| | - John Chan
- Albert Einstein College of Medicine, Bronx, NY
| | - Kathleen A. McDonough
- Wadsworth Center, New York State Department of Health, Albany, NY 12208
- Department of Biomedical Sciences, School of Public Health, University at Albany, SUNY, Albany NY 12208
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Wong AI, Beites T, Planck KA, Fieweger RA, Eckartt KA, Li S, Poulton NC, VanderVen BC, Rhee KY, Schnappinger D, Ehrt S, Rock J. Cyclic AMP is a critical mediator of intrinsic drug resistance and fatty acid metabolism in M. tuberculosis. eLife 2023; 12:e81177. [PMID: 36810158 PMCID: PMC9995111 DOI: 10.7554/elife.81177] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 02/22/2023] [Indexed: 02/24/2023] Open
Abstract
Cyclic AMP (cAMP) is a ubiquitous second messenger that transduces signals from cellular receptors to downstream effectors. Mycobacterium tuberculosis (Mtb), the etiological agent of tuberculosis, devotes a considerable amount of coding capacity to produce, sense, and degrade cAMP. Despite this fact, our understanding of how cAMP regulates Mtb physiology remains limited. Here, we took a genetic approach to investigate the function of the sole essential adenylate cyclase in Mtb H37Rv, Rv3645. We found that a lack of rv3645 resulted in increased sensitivity to numerous antibiotics by a mechanism independent of substantial increases in envelope permeability. We made the unexpected observation that rv3645 is conditionally essential for Mtb growth only in the presence of long-chain fatty acids, a host-relevant carbon source. A suppressor screen further identified mutations in the atypical cAMP phosphodiesterase rv1339 that suppress both fatty acid and drug sensitivity phenotypes in strains lacking rv3645. Using mass spectrometry, we found that Rv3645 is the dominant source of cAMP under standard laboratory growth conditions, that cAMP production is the essential function of Rv3645 in the presence of long-chain fatty acids, and that reduced cAMP levels result in increased long-chain fatty acid uptake and metabolism and increased antibiotic susceptibility. Our work defines rv3645 and cAMP as central mediators of intrinsic multidrug resistance and fatty acid metabolism in Mtb and highlights the potential utility of small molecule modulators of cAMP signaling.
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Affiliation(s)
- Andrew I Wong
- Laboratory of Host-Pathogen Biology, The Rockefeller UniversityNew YorkUnited States
| | - Tiago Beites
- Department of Microbiology and Immunology, Weill Cornell MedicineNew YorkUnited States
| | - Kyle A Planck
- Department of Microbiology and Immunology, Weill Cornell MedicineNew YorkUnited States
- Division of Infectious Diseases, Department of Medicine, Weill Cornell MedicineNew YorkUnited States
| | - Rachael A Fieweger
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell UniversityIthacaUnited States
| | - Kathryn A Eckartt
- Laboratory of Host-Pathogen Biology, The Rockefeller UniversityNew YorkUnited States
| | - Shuqi Li
- Laboratory of Host-Pathogen Biology, The Rockefeller UniversityNew YorkUnited States
| | - Nicholas C Poulton
- Laboratory of Host-Pathogen Biology, The Rockefeller UniversityNew YorkUnited States
| | - Brian C VanderVen
- Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell UniversityIthacaUnited States
| | - Kyu Y Rhee
- Department of Microbiology and Immunology, Weill Cornell MedicineNew YorkUnited States
- Division of Infectious Diseases, Department of Medicine, Weill Cornell MedicineNew YorkUnited States
| | - Dirk Schnappinger
- Department of Microbiology and Immunology, Weill Cornell MedicineNew YorkUnited States
| | - Sabine Ehrt
- Department of Microbiology and Immunology, Weill Cornell MedicineNew YorkUnited States
| | - Jeremy Rock
- Laboratory of Host-Pathogen Biology, The Rockefeller UniversityNew YorkUnited States
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Acetylation of Cyclic AMP Receptor Protein by Acetyl Phosphate Modulates Mycobacterial Virulence. Microbiol Spectr 2023; 11:e0400222. [PMID: 36700638 PMCID: PMC9927398 DOI: 10.1128/spectrum.04002-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The success of Mycobacterium tuberculosis (Mtb) as a pathogen is partly attributed to its ability to sense and respond to dynamic host microenvironments. The cyclic AMP (cAMP) receptor protein (CRP) is closely related to the pathogenicity of Mtb and plays an important role in this process. However, the molecular mechanisms guiding the autoregulation and downstream target genes of CRP while Mtb responds to its environment are not fully understood. Here, it is demonstrated that the acetylation of conserved lysine 193 (K193) within the C-terminal DNA-binding domain of CRP reduces its DNA-binding ability and inhibits transcriptional activity. The reversible acetylation status of CRP K193 was shown to significantly affect mycobacterial growth phenotype, alter the stress response, and regulate the expression of biologically relevant genes using a CRP K193 site-specific mutation. Notably, the acetylation level of K193 decreases under CRP-activating conditions, including the presence of cAMP, low pH, high temperature, and oxidative stress, suggesting that microenvironmental signals can directly regulate CRP K193 acetylation. Both cell- and murine-based infection assays confirmed that CRP K193 is critical to the regulation of Mtb virulence. Furthermore, the acetylation of CRP K193 was shown to be dependent on the intracellular metabolic intermediate acetyl phosphate (AcP), and deacetylation was mediated by NAD+-dependent deacetylases. These findings indicate that AcP-mediated acetylation of CRP K193 decreases CRP activity and negatively regulates the pathogenicity of Mtb. We believe that the underlying mechanisms of cross talk between transcription, posttranslational modifications, and metabolites are a common regulatory mechanism for pathogenic bacteria. IMPORTANCE Mycobacterium tuberculosis (Mtb) is the causative agent of tuberculosis, and the ability of Mtb to survive harsh host conditions has been the subject of intensive research. As a result, we explored the molecular mechanisms guiding downstream target genes of CRP when Mtb responds to its environment. Our study makes a contribution to the literature because we describe the role of acetylated K193 in regulating its binding affinity to target DNA and influencing the virulence of mycobacteria. We discovered that mycobacteria can regulate their pathogenicity through the reversible acetylation of CRP K193 and that this reversible acetylation is mediated by AcP and a NAD+-dependent deacetylase. The regulation of CRPMtb by posttranslational modifications, at the transcriptional level, and by metabolic intermediates contribute to a better understanding of its role in the survival and pathogenicity of mycobacteria.
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Cyclic AMP-Mediated Inhibition of Cholesterol Catabolism in Mycobacterium tuberculosis by the Novel Drug Candidate GSK2556286. Antimicrob Agents Chemother 2023; 67:e0129422. [PMID: 36602336 PMCID: PMC9872607 DOI: 10.1128/aac.01294-22] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Despite the deployment of combination tuberculosis (TB) chemotherapy, efforts to identify shorter, nonrelapsing treatments have resulted in limited success. Recent evidence indicates that GSK2556286 (GSK286), which acts via Rv1625c, a membrane-bound adenylyl cyclase in Mycobacterium tuberculosis, shortens treatment in rodents relative to standard of care drugs. Moreover, GSK286 can replace linezolid in the three-drug, Nix-TB regimen. Given its therapeutic potential, we sought to better understand the mechanism of action of GSK286. The compound blocked growth of M. tuberculosis in cholesterol media and increased intracellular cAMP levels ~50-fold. GSK286 did not inhibit growth of an rv1625c transposon mutant in cholesterol media and did not induce cyclic AMP (cAMP) production in this mutant, suggesting that the compound acts on this adenylyl cyclase. GSK286 also induced cAMP production in Rhodococcus jostii RHA1, a cholesterol-catabolizing actinobacterium, when Rv1625c was heterologously expressed. However, these elevated levels of cAMP did not inhibit growth of R. jostii RHA1 in cholesterol medium. Mutations in rv1625c conferred cross-resistance to GSK286 and the known Rv1625c agonist, mCLB073. Metabolic profiling of M. tuberculosis cells revealed that elevated cAMP levels, induced using either an agonist or a genetic tool, did not significantly affect pools of steroid metabolites in cholesterol-incubated cells. Finally, the inhibitory effect of agonists was not dependent on the N-acetyltransferase MtPat. Together, these data establish that GSK286 is an Rv1625c agonist and sheds light on how cAMP signaling can be manipulated as a novel antibiotic strategy to shorten TB treatments. Nevertheless, the detailed mechanism of action of these compounds remains to be elucidated.
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Thomson M, Liu Y, Nunta K, Cheyne A, Fernandes N, Williams R, Garza-Garcia A, Larrouy-Maumus G. Expression of a novel mycobacterial phosphodiesterase successfully lowers cAMP levels resulting in reduced tolerance to cell wall-targeting antimicrobials. J Biol Chem 2022; 298:102151. [PMID: 35718063 PMCID: PMC9293780 DOI: 10.1016/j.jbc.2022.102151] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 06/09/2022] [Accepted: 06/10/2022] [Indexed: 02/09/2023] Open
Abstract
cAMP and antimicrobial susceptibility in mycobacteriaAntimicrobial tolerance, the ability to survive exposure to antimicrobials via transient nonspecific means, promotes the development of antimicrobial resistance (AMR). The study of the molecular mechanisms that result in antimicrobial tolerance is therefore essential for the understanding of AMR. In gram-negative bacteria, the second messenger molecule 3'',5''-cAMP has been previously shown to be involved in AMR. In mycobacteria, however, the role of cAMP in antimicrobial tolerance has been difficult to probe due to its particular complexity. In order to address this difficulty, here, through unbiased biochemical approaches consisting in the fractionation of clear protein lysate from a mycobacterial strain deleted for the known cAMP phosphodiesterase (Rv0805c) combined with mass spectrometry techniques, we identified a novel cyclic nucleotide-degrading phosphodiesterase enzyme (Rv1339) and developed a system to significantly decrease intracellular cAMP levels through plasmid expression of Rv1339 using the constitutive expression system, pVV16. In Mycobacterium smegmatis mc2155, we demonstrate that recombinant expression of Rv1339 reduced cAMP levels threefold and resulted in altered gene expression, impaired bioenergetics, and a disruption in peptidoglycan biosynthesis leading to decreased tolerance to antimicrobials that target cell wall synthesis such as ethambutol, D-cycloserine, and vancomycin. This work increases our understanding of the role of cAMP in mycobacterial antimicrobial tolerance, and our observations suggest that nucleotide signaling may represent a new target for the development of antimicrobial therapies.
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Affiliation(s)
- Michael Thomson
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, United Kingdom
| | - Yi Liu
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, United Kingdom
| | - Kanokkan Nunta
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, United Kingdom
| | - Ashleigh Cheyne
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, United Kingdom
| | - Nadia Fernandes
- Imperial BRC Genomics Facility, Imperial College London, London, United Kingdom
| | - Richard Williams
- Imperial BRC Genomics Facility, Imperial College London, London, United Kingdom
| | | | - Gerald Larrouy-Maumus
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, United Kingdom,For correspondence: Gerald Larrouy-Maumus
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10
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Wilburn KM, Montague CR, Qin B, Woods AK, Love MS, McNamara CW, Schultz PG, Southard TL, Huang L, Petrassi HM, VanderVen BC. Pharmacological and genetic activation of cAMP synthesis disrupts cholesterol utilization in Mycobacterium tuberculosis. PLoS Pathog 2022; 18:e1009862. [PMID: 35134095 PMCID: PMC8856561 DOI: 10.1371/journal.ppat.1009862] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 02/18/2022] [Accepted: 01/18/2022] [Indexed: 01/27/2023] Open
Abstract
There is a growing appreciation for the idea that bacterial utilization of host-derived lipids, including cholesterol, supports Mycobacterium tuberculosis (Mtb) pathogenesis. This has generated interest in identifying novel antibiotics that can disrupt cholesterol utilization by Mtb in vivo. Here we identify a novel small molecule agonist (V-59) of the Mtb adenylyl cyclase Rv1625c, which stimulates 3', 5'-cyclic adenosine monophosphate (cAMP) synthesis and inhibits cholesterol utilization by Mtb. Similarly, using a complementary genetic approach that induces bacterial cAMP synthesis independent of Rv1625c, we demonstrate that inducing cAMP synthesis is sufficient to inhibit cholesterol utilization in Mtb. Although the physiological roles of individual adenylyl cyclase enzymes in Mtb are largely unknown, here we demonstrate that the transmembrane region of Rv1625c is required during cholesterol metabolism. Finally, the pharmacokinetic properties of Rv1625c agonists have been optimized, producing an orally-available Rv1625c agonist that impairs Mtb pathogenesis in infected mice. Collectively, this work demonstrates a role for Rv1625c and cAMP signaling in controlling cholesterol metabolism in Mtb and establishes that cAMP signaling can be pharmacologically manipulated for the development of new antibiotic strategies.
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Affiliation(s)
- Kaley M. Wilburn
- Microbiology & Immunology, Cornell University, Ithaca, New York, United States of America
| | - Christine R. Montague
- Microbiology & Immunology, Cornell University, Ithaca, New York, United States of America
| | - Bo Qin
- Calibr, a division of The Scripps Research Institute, San Diego, California, United States of America
| | - Ashley K. Woods
- Calibr, a division of The Scripps Research Institute, San Diego, California, United States of America
| | - Melissa S. Love
- Calibr, a division of The Scripps Research Institute, San Diego, California, United States of America
| | - Case W. McNamara
- Calibr, a division of The Scripps Research Institute, San Diego, California, United States of America
| | - Peter G. Schultz
- Calibr, a division of The Scripps Research Institute, San Diego, California, United States of America
| | - Teresa L. Southard
- Biomedical Sciences, Cornell University, Ithaca, New York, United States of America
| | - Lu Huang
- Microbiology & Immunology, Cornell University, Ithaca, New York, United States of America
| | - H. Michael Petrassi
- Calibr, a division of The Scripps Research Institute, San Diego, California, United States of America
| | - Brian C. VanderVen
- Microbiology & Immunology, Cornell University, Ithaca, New York, United States of America
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11
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Ssekitoleko J, Ojok L, Abd El Wahed A, Erume J, Amanzada A, Eltayeb E, Eltom KH, Okuni JB. Mycobacterium avium subsp. paratuberculosis Virulence: A Review. Microorganisms 2021; 9:2623. [PMID: 34946224 PMCID: PMC8707695 DOI: 10.3390/microorganisms9122623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 12/08/2021] [Accepted: 12/16/2021] [Indexed: 11/17/2022] Open
Abstract
To propose a solution for control of Mycobacterium avium subsp. paratuberculosis (MAP) infections in animals as well as in humans, and develop effective prevention, diagnostic and treatment strategies, it is essential to understand the molecular mechanisms of MAP pathogenesis. In the present review, we discuss the mechanisms utilised by MAP to overcome the host defense system to achieve the virulence status. Putative MAP virulence genes are mentioned and their probable roles in view of other mycobacteria are discussed. This review provides information on MAP strain diversity, putative MAP virulence factors and highlights the knowledge gaps regarding MAP virulence mechanisms that may be important in control and prevention of paratuberculosis.
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Affiliation(s)
- Judah Ssekitoleko
- College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala P. O. Box 7062, Uganda; (J.S.); (L.O.); (J.E.)
- Department of Livestock Health Research, Rwebitaba Zonal Agricultural Research and Development Institute, National Agricultural Research Organisation, Entebbe P. O. Box 295, Uganda
| | - Lonzy Ojok
- College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala P. O. Box 7062, Uganda; (J.S.); (L.O.); (J.E.)
- Department of Pathology, Faculty of Medicine, Gulu University, Gulu P. O. Box 166, Uganda
| | - Ahmed Abd El Wahed
- Institute of Animal Hygiene and Veterinary Public Health, Leipzig University, D-04103 Leipzig, Germany
| | - Joseph Erume
- College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala P. O. Box 7062, Uganda; (J.S.); (L.O.); (J.E.)
| | - Ahmad Amanzada
- Department of Gastroenterology and Gastrointestinal Oncology, University Medical Centre Goettingen, D-37075 Goettingen, Germany;
| | - ElSagad Eltayeb
- Ibn Sina Specialised Hospital, Mohammed Najeeb St., Khartoum 11560, Sudan;
- Faculty of Medicine, Al Neelain University, 52nd St., Khartoum 11112, Sudan
| | - Kamal H. Eltom
- Unit of Animal Health and Safety of Animal Products, Institute for Studies and Promotion of Animal Exports, University of Khartoum, Shambat, Khartoum North 13314, Sudan;
| | - Julius Boniface Okuni
- College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala P. O. Box 7062, Uganda; (J.S.); (L.O.); (J.E.)
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12
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Gonzaga de França Lopes L, Gouveia Júnior FS, Karine Medeiros Holanda A, Maria Moreira de Carvalho I, Longhinotti E, Paulo TF, Abreu DS, Bernhardt PV, Gilles-Gonzalez MA, Cirino Nogueira Diógenes I, Henrique Silva Sousa E. Bioinorganic systems responsive to the diatomic gases O2, NO, and CO: From biological sensors to therapy. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2021.214096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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13
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Gárate F, Dokas S, Lanfranco MF, Canavan C, Wang I, Correia JJ, Maillard RA. cAMP is an allosteric modulator of DNA-binding specificity in the cAMP receptor protein from Mycobacterium tuberculosis. J Biol Chem 2021; 296:100480. [PMID: 33640453 PMCID: PMC8026907 DOI: 10.1016/j.jbc.2021.100480] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 02/21/2021] [Accepted: 02/24/2021] [Indexed: 11/28/2022] Open
Abstract
Allosteric proteins with multiple subunits and ligand-binding sites are central in regulating biological signals. The cAMP receptor protein from Mycobacterium tuberculosis (CRPMTB) is a global regulator of transcription composed of two identical subunits, each one harboring structurally conserved cAMP- and DNA-binding sites. The mechanisms by which these four binding sites are allosterically coupled in CRPMTB remain unclear. Here, we investigate the binding mechanism between CRPMTB and cAMP, and the linkage between cAMP and DNA interactions. Using calorimetric and fluorescence-based assays, we find that cAMP binding is entropically driven and displays negative cooperativity. Fluorescence anisotropy experiments show that apo-CRPMTB forms high-order CRPMTB–DNA oligomers through interactions with nonspecific DNA sequences or preformed CRPMTB–DNA complexes. Moreover, we find that cAMP prevents and reverses the formation of CRPMTB–DNA oligomers, reduces the affinity of CRPMTB for nonspecific DNA sequences, and stabilizes a 1-to-1 CRPMTB–DNA complex, but does not increase the affinity for DNA like in the canonical CRP from Escherichia coli (CRPEcoli). DNA-binding assays as a function of cAMP concentration indicate that one cAMP molecule per homodimer dissociates high-order CRPMTB–DNA oligomers into 1-to-1 complexes. These cAMP-mediated allosteric effects are lost in the double-mutant L47P/E178K found in CRP from Mycobacterium bovis Bacille Calmette-Guérin (CRPBCG). The functional behavior, thermodynamic stability, and dimerization constant of CRPBCG are not due to additive effects of L47P and E178K, indicating long-range interactions between these two sites. Altogether, we provide a previously undescribed archetype of cAMP-mediated allosteric regulation that differs from CRPEcoli, illustrating that structural homology does not imply allosteric homology.
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Affiliation(s)
- Fernanda Gárate
- Department of Chemistry, Georgetown University, Washington, District of Columbia, USA
| | - Stephen Dokas
- Department of Chemistry, Georgetown University, Washington, District of Columbia, USA
| | - Maria Fe Lanfranco
- Department of Chemistry, Georgetown University, Washington, District of Columbia, USA
| | - Clare Canavan
- Department of Chemistry, Georgetown University, Washington, District of Columbia, USA
| | - Irina Wang
- Department of Chemistry, Georgetown University, Washington, District of Columbia, USA
| | - John J Correia
- Department of Cell and Molecular Biology, The University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Rodrigo A Maillard
- Department of Chemistry, Georgetown University, Washington, District of Columbia, USA.
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14
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Forrellad MA, Blanco FC, Marrero Diaz de Villegas R, Vázquez CL, Yaneff A, García EA, Gutierrez MG, Durán R, Villarino A, Bigi F. Rv2577 of Mycobacterium tuberculosis Is a Virulence Factor With Dual Phosphatase and Phosphodiesterase Functions. Front Microbiol 2020; 11:570794. [PMID: 33193164 PMCID: PMC7642983 DOI: 10.3389/fmicb.2020.570794] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 09/25/2020] [Indexed: 11/20/2022] Open
Abstract
Tuberculosis, a lung disease caused by Mycobacterium tuberculosis (Mtb), is one of the ten leading causes of death worldwide affecting mainly developing countries. Mtb can persist and survive inside infected cells through modulation of host antibacterial attack, i.e., by avoiding the maturation of phagosome containing mycobacteria to more acidic endosomal compartment. In addition, bacterial phosphatases play a central role in the interplay between host cells and Mtb. In this study, we characterized the Rv2577 of Mtb as a potential alkaline phosphatase/phosphodiesterase enzyme. By an in vitro kinetic assay, we demonstrated that purified Rv2577 expressed in Mycobacterium smegmatis displays both enzyme activities, as evidenced by using the artificial substrates p-NPP and bis-(p-NPP). In addition, a three-dimensional model of Rv2577 allowed us to define the catalytic amino acid residues of the active site, which were confirmed by site-directed mutagenesis and enzyme activity analysis, being characteristic of a member of the metallophosphatase superfamily. Finally, a mutation introduced in Rv2577 reduced the replication of Mtb in mouse organs and impaired the arrest of phagosomes containing mycobacteria in early endosomes; which indicates Rv2577 plays a role in Mtb virulence.
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Affiliation(s)
- Marina Andrea Forrellad
- Instituto de Agrobiotecnología y Biología Molecular (IABIMO), Instituto Nacional de Tecnología Agropecuaria-Consejo Nacional de Investigaciones Científicas y Técnicas (INTA-CONICET), INTA, Buenos Aires, Argentina
| | - Federico Carlos Blanco
- Instituto de Agrobiotecnología y Biología Molecular (IABIMO), Instituto Nacional de Tecnología Agropecuaria-Consejo Nacional de Investigaciones Científicas y Técnicas (INTA-CONICET), INTA, Buenos Aires, Argentina
| | - Rubén Marrero Diaz de Villegas
- Instituto de Agrobiotecnología y Biología Molecular (IABIMO), Instituto Nacional de Tecnología Agropecuaria-Consejo Nacional de Investigaciones Científicas y Técnicas (INTA-CONICET), INTA, Buenos Aires, Argentina
| | - Cristina Lourdes Vázquez
- Instituto de Agrobiotecnología y Biología Molecular (IABIMO), Instituto Nacional de Tecnología Agropecuaria-Consejo Nacional de Investigaciones Científicas y Técnicas (INTA-CONICET), INTA, Buenos Aires, Argentina
| | - Agustín Yaneff
- Instituto de Investigaciones Farmacológicas (ININFA), Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad de Buenos Aires (CONICET-UBA), Cuidad Autónoma de Buenos Aires, Argentina
| | - Elizabeth Andrea García
- Instituto de Agrobiotecnología y Biología Molecular (IABIMO), Instituto Nacional de Tecnología Agropecuaria-Consejo Nacional de Investigaciones Científicas y Técnicas (INTA-CONICET), INTA, Buenos Aires, Argentina
| | | | - Rosario Durán
- Unidad de Bioquímica y Proteómica Analítica (UBYPA), Instituto de Investigaciones Biológicas Clemente Estable & Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Andrea Villarino
- Sección Bioquímica, Facultad de Ciencias, Universidad de la República (UdelaR), Montevideo, Uruguay
| | - Fabiana Bigi
- Instituto de Agrobiotecnología y Biología Molecular (IABIMO), Instituto Nacional de Tecnología Agropecuaria-Consejo Nacional de Investigaciones Científicas y Técnicas (INTA-CONICET), INTA, Buenos Aires, Argentina
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15
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Phillips IL, Everman JL, Bermudez LE, Danelishvili L. Acanthamoeba castellanii as a Screening Tool for Mycobacterium avium Subspecies paratuberculosis Virulence Factors with Relevance in Macrophage Infection. Microorganisms 2020; 8:microorganisms8101571. [PMID: 33066018 PMCID: PMC7601679 DOI: 10.3390/microorganisms8101571] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 10/08/2020] [Accepted: 10/09/2020] [Indexed: 02/05/2023] Open
Abstract
The high prevalence of Johne's disease has driven a continuous effort to more readily understand the pathogenesis of the etiological causative bacterium, Mycobacterium avium subsp. paratuberculosis (MAP), and to develop effective preventative measures for infection spread. In this study, we aimed to create an in vivo MAP infection model employing an environmental protozoan host and used it as a tool for selection of bacterial virulence determinants potentially contributing to MAP survival in mammalian host macrophages. We utilized Acanthamoeba castellanii (amoeba) to explore metabolic consequences of the MAP-host interaction and established a correlation between metabolic changes of this phagocytic host and MAP virulence. Using the library of gene knockout mutants, we identified MAP clones that can either enhance or inhibit amoeba metabolism and we discovered that, for most part, it mirrors the pattern of MAP attenuation or survival during infection of macrophages. It was found that MAP mutants that induced an increase in amoeba metabolism were defective in intracellular growth in macrophages. However, MAP clones that exhibited low metabolic alteration in amoeba were able to survive at a greater rate within mammalian cells, highlighting importance of both category of genes in bacterial pathogenesis. Sequencing of MAP mutants has identified several virulence factors previously shown to have a biological relevance in mycobacterial survival and intracellular growth in phagocytic cells. In addition, we uncovered new genetic determinants potentially contributing to MAP pathogenicity. Results of this study support the use of the amoeba model system as a quick initial screening tool for selection of virulence factors of extremely slow-grower MAP that is challenging to study.
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Affiliation(s)
- Ida L. Phillips
- Department of Biomedical Sciences, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331, USA; (I.L.P.); (L.E.B.)
| | - Jamie L. Everman
- Center for Genes, Environment, and Health, National Jewish Health, Denver, CO 80206, USA;
| | - Luiz E. Bermudez
- Department of Biomedical Sciences, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331, USA; (I.L.P.); (L.E.B.)
- Department of Microbiology, College of Sciences, Oregon State University, Corvallis, OR 97331, USA
| | - Lia Danelishvili
- Department of Biomedical Sciences, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331, USA; (I.L.P.); (L.E.B.)
- Correspondence: ; Tel.: +541-737-6544; Fax: +541-737-2730
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16
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Liu Y, Rebollo-Ramirez S, Larrouy-Maumus G. Metabolomics reveals that the cAMP receptor protein regulates nitrogen and peptidoglycan synthesis in Mycobacterium tuberculosis. RSC Adv 2020; 10:26212-26219. [PMID: 33747441 PMCID: PMC7938724 DOI: 10.1039/d0ra05153e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 07/07/2020] [Indexed: 12/30/2022] Open
Abstract
Mycobacterium tuberculosis requires extensive sensing and response to environment for its successful survival and pathogenesis, and signalling by cyclic adenosine 3',5'-monophosphate (cAMP) is an important mechanism. cAMP regulates expression of target genes via interaction with downstream proteins, one of which is cAMP receptor protein (CRP), a global transcriptional regulator. Previous genomic works had identified regulon of CRP and investigated transcriptional changes in crp deletion mutant, however a link to downstream metabolomic events were lacking, which would help better understand roles of CRP. This work aims at investigating changes at metabolome level in M. tuberculosis crp deletion mutant combining untargeted LC-MS analysis and 13C isotope tracing analysis. The results were compared with previously published RNA sequencing data. We identified increasing abundances of metabolites related to nitrogen metabolism including ornithine, citrulline and glutamate derivatives, while 13C isotope labelling analysis further showed changes in turnover of these metabolites and amino acids, suggesting regulatory roles of CRP in nitrogen metabolism. Upregulation of diaminopimelic acid and its related genes also suggested role of CRP in regulation of peptidoglycan synthesis. This study provides insights on metabolomic aspects of cAMP-CRP regulatory pathway in M. tuberculosis and links to previously published transcriptomic data drawing a more complete map.
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Affiliation(s)
- Yi Liu
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, UK.
| | - Sonia Rebollo-Ramirez
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, UK.
| | - Gerald Larrouy-Maumus
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, UK.
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17
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Prasad H, Shenoy AR, Visweswariah SS. Cyclic nucleotides, gut physiology and inflammation. FEBS J 2020; 287:1970-1981. [PMID: 31889413 DOI: 10.1111/febs.15198] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 12/10/2019] [Accepted: 12/30/2019] [Indexed: 12/27/2022]
Abstract
Misregulation of gut function and homeostasis impinges on the overall well-being of the entire organism. Diarrheal disease is the second leading cause of death in children under 5 years of age, and globally, 1.7 billion cases of childhood diarrhea are reported every year. Accompanying diarrheal episodes are a number of secondary effects in gut physiology and structure, such as erosion of the mucosal barrier that lines the gut, facilitating further inflammation of the gut in response to the normal microbiome. Here, we focus on pathogenic bacteria-mediated diarrhea, emphasizing the role of cyclic adenosine 3',5'-monophosphate and cyclic guanosine 3',5'-monophosphate in driving signaling outputs that result in the secretion of water and ions from the epithelial cells of the gut. We also speculate on how this aberrant efflux and influx of ions could modulate inflammasome signaling, and therefore cell survival and maintenance of gut architecture and function.
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Affiliation(s)
- Hari Prasad
- Department of Molecular Reproduction, Development and Genetics, Indian Institute of Science, Bengaluru, India
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18
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Grüschow S, Athukoralage JS, Graham S, Hoogeboom T, White MF. Cyclic oligoadenylate signalling mediates Mycobacterium tuberculosis CRISPR defence. Nucleic Acids Res 2019; 47:9259-9270. [PMID: 31392987 PMCID: PMC6755085 DOI: 10.1093/nar/gkz676] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 07/19/2019] [Accepted: 07/30/2019] [Indexed: 12/26/2022] Open
Abstract
The CRISPR system provides adaptive immunity against mobile genetic elements (MGE) in prokaryotes. In type III CRISPR systems, an effector complex programmed by CRISPR RNA detects invading RNA, triggering a multi-layered defence that includes target RNA cleavage, licencing of an HD DNA nuclease domain and synthesis of cyclic oligoadenylate (cOA) molecules. cOA activates the Csx1/Csm6 family of effectors, which degrade RNA non-specifically to enhance immunity. Type III systems are found in diverse archaea and bacteria, including the human pathogen Mycobacterium tuberculosis. Here, we report a comprehensive analysis of the in vitro and in vivo activities of the type III-A M. tuberculosis CRISPR system. We demonstrate that immunity against MGE may be achieved predominantly via a cyclic hexa-adenylate (cA6) signalling pathway and the ribonuclease Csm6, rather than through DNA cleavage by the HD domain. Furthermore, we show for the first time that a type III CRISPR system can be reprogrammed by replacing the effector protein, which may be relevant for maintenance of immunity in response to pressure from viral anti-CRISPRs. These observations demonstrate that M. tuberculosis has a fully-functioning CRISPR interference system that generates a range of cyclic and linear oligonucleotides of known and unknown functions, potentiating fundamental and applied studies.
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Affiliation(s)
- Sabine Grüschow
- Biomedical Sciences Research Complex, School of Biology, University of St Andrews, St Andrews KY16 9ST, UK
| | - Januka S Athukoralage
- Biomedical Sciences Research Complex, School of Biology, University of St Andrews, St Andrews KY16 9ST, UK
| | - Shirley Graham
- Biomedical Sciences Research Complex, School of Biology, University of St Andrews, St Andrews KY16 9ST, UK
| | - Tess Hoogeboom
- Biomedical Sciences Research Complex, School of Biology, University of St Andrews, St Andrews KY16 9ST, UK
| | - Malcolm F White
- Biomedical Sciences Research Complex, School of Biology, University of St Andrews, St Andrews KY16 9ST, UK
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19
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Kathleen M, Patrick B. Editorial: Introduction to thematic issue 'Molecular Effectors of Tuberculosis Pathogenesis'. Pathog Dis 2018; 76:5307233. [PMID: 30726953 DOI: 10.1093/femspd/fty077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- McDonough Kathleen
- Wadsworth Center, NYS Department of Health; and Department of Biomedical Sciences, University at Albany, SUNY, USA
| | - Brennan Patrick
- Department of Microbiology, Immunology and Pathology, Colorado State University, USA
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