1
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Bull TJ, Munshi T, Lopez-Perez PM, Tran AC, Cosgrove C, Bartolf A, Menichini M, Rindi L, Parigger L, Malanovic N, Lohner K, Wang CJH, Fatima A, Martin LL, Esin S, Batoni G, Hilpert K. Specific Cationic Antimicrobial Peptides Enhance the Recovery of Low-Load Quiescent Mycobacterium tuberculosis in Routine Diagnostics. Int J Mol Sci 2023; 24:17555. [PMID: 38139385 PMCID: PMC10743970 DOI: 10.3390/ijms242417555] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 12/07/2023] [Accepted: 12/11/2023] [Indexed: 12/24/2023] Open
Abstract
The culture confirmation of Mycobacterium tuberculosis (MTB) remains the gold standard for the diagnosis of Tuberculosis (TB) with culture conversion representing proof of cure. However, over 40% of TB samples fail to isolate MTB even though many patients remain infectious due to the presence of viable non-culturable forms. Previously, we have shown that two short cationic peptides, T14D and TB08L, induce a hormetic response at low concentrations, leading to a stimulation of growth in MTB and the related animal pathogen Mycobacterium bovis (bTB). Here, we examine these peptides showing they can influence the mycobacterial membrane integrity and function through membrane potential reduction. We also show this disruption is associated with an abnormal reduction in transcriptomic signalling from specific mycobacterial membrane sensors that normally monitor the immediate cellular environment and maintain the non-growing phenotype. We observe that exposing MTB or bTB to these peptides at optimal concentrations rapidly represses signalling mechanisms maintaining dormancy phenotypes, which leads to the promotion of aerobic metabolism and conversion into a replicative phenotype. We further show a practical application of these peptides as reagents able to enhance conventional routine culture methods by stimulating mycobacterial growth. We evaluated the ability of a peptide-supplemented sample preparation and culture protocol to isolate the MTB against a gold standard routine method tested in parallel on 255 samples from 155 patients with suspected TB. The peptide enhancement increased the sample positivity rate by 46% and decreased the average time to sample positivity of respiratory/faecal sampling by seven days. The most significant improvements in isolation rates were from sputum smear-negative low-load samples and faeces. The peptide enhancement increased sampling test sensitivity by 19%, recovery in samples from patients with a previously culture-confirmed TB by 20%, and those empirically treated for TB by 21%. We conclude that sample decontamination and culture enhancement with D-enantiomer peptides offer good potential for the much-needed improvement of the culture confirmation of TB.
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Affiliation(s)
- Tim J. Bull
- Institute of Infection and Immunity, St. George’s, University of London, Cranmer Terrace, London SW17 0RE, UK (K.H.)
| | - Tulika Munshi
- Institute of Infection and Immunity, St. George’s, University of London, Cranmer Terrace, London SW17 0RE, UK (K.H.)
| | | | - Andy C. Tran
- Institute of Infection and Immunity, St. George’s, University of London, Cranmer Terrace, London SW17 0RE, UK (K.H.)
| | - Catherine Cosgrove
- St. George’s Hospital NHS Trust, Cranmer Terrace, London SW17 0RE, UK; (C.C.)
| | - Angela Bartolf
- St. George’s Hospital NHS Trust, Cranmer Terrace, London SW17 0RE, UK; (C.C.)
| | - Melissa Menichini
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy (L.R.); (S.E.); (G.B.)
| | - Laura Rindi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy (L.R.); (S.E.); (G.B.)
| | - Lena Parigger
- Institute of Molecular Biosciences, Biophysics Division, University of Graz, Humboldstrasse 50/III, 800 Graz, Austria; (L.P.); (K.L.)
| | - Nermina Malanovic
- Institute of Molecular Biosciences, Biophysics Division, University of Graz, Humboldstrasse 50/III, 800 Graz, Austria; (L.P.); (K.L.)
| | - Karl Lohner
- Institute of Molecular Biosciences, Biophysics Division, University of Graz, Humboldstrasse 50/III, 800 Graz, Austria; (L.P.); (K.L.)
| | - Carl J. H. Wang
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia (A.F.); (L.L.M.)
| | - Anam Fatima
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia (A.F.); (L.L.M.)
| | - Lisandra L. Martin
- School of Chemistry, Monash University, Clayton, VIC 3800, Australia (A.F.); (L.L.M.)
| | - Semih Esin
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy (L.R.); (S.E.); (G.B.)
| | - Giovanna Batoni
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy (L.R.); (S.E.); (G.B.)
| | - Kai Hilpert
- Institute of Infection and Immunity, St. George’s, University of London, Cranmer Terrace, London SW17 0RE, UK (K.H.)
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2
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von Rosen T, Keller LM, Weber-Ban E. Survival in Hostile Conditions: Pupylation and the Proteasome in Actinobacterial Stress Response Pathways. Front Mol Biosci 2021; 8:685757. [PMID: 34179091 PMCID: PMC8223512 DOI: 10.3389/fmolb.2021.685757] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 05/04/2021] [Indexed: 12/31/2022] Open
Abstract
Bacteria employ a multitude of strategies to cope with the challenges they face in their natural surroundings, be it as pathogens, commensals or free-living species in rapidly changing environments like soil. Mycobacteria and other Actinobacteria acquired proteasomal genes and evolved a post-translational, ubiquitin-like modification pathway called pupylation to support their survival under rapidly changing conditions and under stress. The proteasomal 20S core particle (20S CP) interacts with ring-shaped activators like the hexameric ATPase Mpa that recruits pupylated substrates. The proteasomal subunits, Mpa and pupylation enzymes are encoded in the so-called Pup-proteasome system (PPS) gene locus. Genes in this locus become vital for bacteria to survive during periods of stress. In the successful human pathogen Mycobacterium tuberculosis, the 20S CP is essential for survival in host macrophages. Other members of the PPS and proteasomal interactors are crucial for cellular homeostasis, for example during the DNA damage response, iron and copper regulation, and heat shock. The multiple pathways that the proteasome is involved in during different stress responses suggest that the PPS plays a vital role in bacterial protein quality control and adaptation to diverse challenging environments.
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Affiliation(s)
- Tatjana von Rosen
- Institute of Molecular Biology and Biophysics, ETH Zurich, Zurich, Switzerland
| | - Lena Ml Keller
- Institute of Molecular Biology and Biophysics, ETH Zurich, Zurich, Switzerland
| | - Eilika Weber-Ban
- Institute of Molecular Biology and Biophysics, ETH Zurich, Zurich, Switzerland
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3
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Texier P, Bordes P, Nagpal J, Sala AJ, Mansour M, Cirinesi AM, Xu X, Dougan DA, Genevaux P. ClpXP-mediated Degradation of the TAC Antitoxin is Neutralized by the SecB-like Chaperone in Mycobacterium tuberculosis. J Mol Biol 2021; 433:166815. [PMID: 33450247 DOI: 10.1016/j.jmb.2021.166815] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 12/27/2020] [Accepted: 01/05/2021] [Indexed: 01/31/2023]
Abstract
Bacterial toxin-antitoxin (TA) systems are composed of a deleterious toxin and its antagonistic antitoxin. They are widespread in bacterial genomes and mobile genetic elements, and their functions remain largely unknown. Some TA systems, known as TAC modules, include a cognate SecB-like chaperone that assists the antitoxin in toxin inhibition. Here, we have investigated the involvement of proteases in the activation cycle of the TAC system of the human pathogen Mycobacterium tuberculosis. We show that the deletion of endogenous AAA+ proteases significantly bypasses the need for a dedicated chaperone and identify the mycobacterial ClpXP1P2 complex as the main protease involved in TAC antitoxin degradation. In addition, we show that the ClpXP1P2 degron is located at the extreme C-terminal end of the chaperone addiction (ChAD) region of the antitoxin, demonstrating that ChAD functions as a hub for both chaperone binding and recognition by proteases.
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Affiliation(s)
- Pauline Texier
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Patricia Bordes
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France.
| | - Jyotsna Nagpal
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Ambre Julie Sala
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Moise Mansour
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Anne-Marie Cirinesi
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Xibing Xu
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - David Andrew Dougan
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia.
| | - Pierre Genevaux
- Laboratoire de Microbiologie et de Génétique Moléculaires, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France.
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4
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Tan YZ, Zhang L, Rodrigues J, Zheng RB, Giacometti SI, Rosário AL, Kloss B, Dandey VP, Wei H, Brunton R, Raczkowski AM, Athayde D, Catalão MJ, Pimentel M, Clarke OB, Lowary TL, Archer M, Niederweis M, Potter CS, Carragher B, Mancia F. Cryo-EM Structures and Regulation of Arabinofuranosyltransferase AftD from Mycobacteria. Mol Cell 2020; 78:683-699.e11. [PMID: 32386575 PMCID: PMC7263364 DOI: 10.1016/j.molcel.2020.04.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 02/21/2020] [Accepted: 04/13/2020] [Indexed: 01/21/2023]
Abstract
Mycobacterium tuberculosis causes tuberculosis, a disease that kills over 1 million people each year. Its cell envelope is a common antibiotic target and has a unique structure due, in part, to two lipidated polysaccharides-arabinogalactan and lipoarabinomannan. Arabinofuranosyltransferase D (AftD) is an essential enzyme involved in assembling these glycolipids. We present the 2.9-Å resolution structure of M. abscessus AftD, determined by single-particle cryo-electron microscopy. AftD has a conserved GT-C glycosyltransferase fold and three carbohydrate-binding modules. Glycan array analysis shows that AftD binds complex arabinose glycans. Additionally, AftD is non-covalently complexed with an acyl carrier protein (ACP). 3.4- and 3.5-Å structures of a mutant with impaired ACP binding reveal a conformational change, suggesting that ACP may regulate AftD function. Mutagenesis experiments using a conditional knockout constructed in M. smegmatis confirm the essentiality of the putative active site and the ACP binding for AftD function.
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Affiliation(s)
- Yong Zi Tan
- Department of Physiology and Cellular Biophysics, Columbia University, New York, NY 10032, USA; National Resource for Automated Molecular Microscopy, Simons Electron Microscopy Center, New York Structural Biology Center, New York, NY 10027, USA
| | - Lei Zhang
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - José Rodrigues
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), 2780-157 Oeiras, Portugal
| | | | - Sabrina I Giacometti
- Department of Physiology and Cellular Biophysics, Columbia University, New York, NY 10032, USA
| | - Ana L Rosário
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), 2780-157 Oeiras, Portugal
| | - Brian Kloss
- Center on Membrane Protein Production and Analysis, New York Structural Biology Center, New York, NY 10027, USA
| | - Venkata P Dandey
- National Resource for Automated Molecular Microscopy, Simons Electron Microscopy Center, New York Structural Biology Center, New York, NY 10027, USA
| | - Hui Wei
- National Resource for Automated Molecular Microscopy, Simons Electron Microscopy Center, New York Structural Biology Center, New York, NY 10027, USA
| | - Richard Brunton
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2G2, Canada
| | - Ashleigh M Raczkowski
- Simons Electron Microscopy Center, New York Structural Biology Center, New York, NY 10027, USA
| | - Diogo Athayde
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), 2780-157 Oeiras, Portugal
| | - Maria João Catalão
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal
| | - Madalena Pimentel
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, 1649-003 Lisboa, Portugal
| | - Oliver B Clarke
- Department of Physiology and Cellular Biophysics, Columbia University, New York, NY 10032, USA; Department of Anesthesiology, Columbia University, New York, NY 10032, USA
| | - Todd L Lowary
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2G2, Canada; Institute of Biological Chemistry, Academia Sinica, Academia Road, Section 2, #128 Nangang, Taipei 11529, Taiwan
| | - Margarida Archer
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), 2780-157 Oeiras, Portugal
| | - Michael Niederweis
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Clinton S Potter
- National Resource for Automated Molecular Microscopy, Simons Electron Microscopy Center, New York Structural Biology Center, New York, NY 10027, USA; Simons Electron Microscopy Center, New York Structural Biology Center, New York, NY 10027, USA; Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Bridget Carragher
- National Resource for Automated Molecular Microscopy, Simons Electron Microscopy Center, New York Structural Biology Center, New York, NY 10027, USA; Simons Electron Microscopy Center, New York Structural Biology Center, New York, NY 10027, USA; Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA.
| | - Filippo Mancia
- Department of Physiology and Cellular Biophysics, Columbia University, New York, NY 10032, USA.
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5
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Bigi M, Vazquez CL, Castelão ABC, García EA, Cataldi AA, Jackson M, McNeil M, Soria M, Zumárraga MJ, Cabruja M, Gago G, Blanco FC, Nishibe C, Almeida NF, de Araújo FR, Bigi F. Analysing nonsynonymous mutations between two Mycobacterium bovis strains with contrasting pathogenic profiles. Vet Microbiol 2019; 239:108482. [PMID: 31759775 DOI: 10.1016/j.vetmic.2019.108482] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 10/22/2019] [Accepted: 10/24/2019] [Indexed: 01/03/2023]
Abstract
Mycobacterium bovis (M. bovis) is the causative agent of bovine tuberculosis, a chronic infectious disease that can affect cattle, other domesticated species, wild animals and humans. This disease produces important economic losses worldwide. Two M. bovis strains (04-303 and 534) have been isolated in Argentina. Whereas the 04-303 strain was isolated from a wild boar, the 534 strain was obtained from cattle. In a previous study, six weeks after infection, the 04-303 strain induced 100% mortality in mice. By contrast, mice infected with the 534 strain survived, with limited tissue damage, after four months. In this study we compared all predictive proteins encoded in both M. bovis genomes. The comparative analysis revealed 141 polymorphic proteins between both strains. From these proteins, nine virulence proteins showed polymorphisms in 04-303, whereas five did it in the 534 strain. Remarkably, both strains contained a high level of polymorphism in proteins related to phthiocerol dimycocerosate (PDIM) synthesis or transport. Further experimental evidence indicated that only mutations in the 534 strain have an impact on PDIM synthesis. The observed reduction in PDIM content in the 534 strain, together with its low capacity to induce phagosome arrest, may be associated with the reported deficiency of this strain to replicate and survive inside bovine macrophages. The findings of this study could contribute to a better understanding of pathogenicity and virulence aspects of M. bovis, which is essential for further studies aiming at developing new vaccines and diagnostic techniques for bovines.
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Affiliation(s)
- Mercedes Bigi
- Universidad de Buenos Aires, Facultad de Agronomía, Cátedra de Microbiología Agrícola, INBA-CONICET, Buenos Aires, Argentina.
| | | | - Ana Beatriz C Castelão
- Faculdade de Medicina Veterinária e Zootecnia, Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil.
| | | | | | - Mary Jackson
- Colorado State University, Dept. of Microbiology, Immunology and Pathology, USA.
| | - Michael McNeil
- Colorado State University, Dept. of Microbiology, Immunology and Pathology, USA.
| | - Marcelo Soria
- Universidad de Buenos Aires, Facultad de Agronomía, Cátedra de Microbiología Agrícola, INBA-CONICET, Buenos Aires, Argentina.
| | | | - Matias Cabruja
- Laboratory of Physiology and Genetics of Actinomycetes, Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina.
| | - Gabriela Gago
- Laboratory of Physiology and Genetics of Actinomycetes, Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina.
| | | | - Christiane Nishibe
- Faculdade de Computação, Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil.
| | - Nalvo F Almeida
- Faculdade de Computação, Universidade Federal de Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul, Brazil.
| | | | - Fabiana Bigi
- Instituto de Biotecnología, IABIMO, CICVyA/INTA, Argentina.
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6
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On a stake-out: Mycobacterial small RNA identification and regulation. Noncoding RNA Res 2019; 4:86-95. [PMID: 32083232 PMCID: PMC7017587 DOI: 10.1016/j.ncrna.2019.05.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 04/30/2019] [Accepted: 05/12/2019] [Indexed: 12/23/2022] Open
Abstract
Persistence of mycobacteria in the hostile environment of human macrophage is pivotal for its successful pathogenesis. Rapid adaptation to diverse stresses is the key aspect for their survival in the host cells. A range of heterogeneous mechanisms operate in bacteria to retaliate stress conditions. Small RNAs (sRNA) have been implicated in many of those mechanisms in either a single or multiple regulatory networks to post-transcriptionally modulate bacterial gene expression. Although small RNA profiling in mycobacteria by advanced technologies like deep sequencing, tilling microarray etc. have identified hundreds of sRNA, however, a handful of those small RNAs have been unearthed with precise regulatory mechanism. Extensive investigations on sRNA-mediated gene regulations in eubacteria like Escherichia coli revealed the existence of a plethora of distinctive sRNA mechanisms e.g. base pairing, protein sequestration, RNA decoy etc. Increasing studies on mycobacterial sRNA also discovered several eccentric mechanisms where sRNAs act at the posttranscriptional stage to either activate or repress target gene expression that lead to promote mycobacterial survival in stresses. Several intrinsic features like high GC content, absence of any homologue of abundant RNA chaperones, Hfq and ProQ, isolate sRNA mechanisms of mycobacteria from that of other bacteria. An insightful approach has been taken in this review to describe sRNA identification and its regulations in mycobacterial species especially in Mycobacterium tuberculosis.
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Key Words
- Anti-antisense
- Antisense
- Base pairing
- CDS, coding sequence
- Gene regulation by sRNA
- IGR, intergenic region
- ORF, open reading frame
- RBS, Ribosome binding site
- RNAP, RNA polymerase
- SD, Shine Dalgarno sequence
- Small RNAs
- TF, transcription factor
- TIR, translation initiation region
- UTR, untranslated region
- nt, nucleotide
- sRNA, small RNA
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7
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Kim WS, Kim JS, Kim HM, Kwon KW, Eum SY, Shin SJ. Comparison of immunogenicity and vaccine efficacy between heat-shock proteins, HSP70 and GrpE, in the DnaK operon of Mycobacterium tuberculosis. Sci Rep 2018; 8:14411. [PMID: 30258084 PMCID: PMC6158166 DOI: 10.1038/s41598-018-32799-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 09/13/2018] [Indexed: 12/17/2022] Open
Abstract
Antigens (Ags) in Mycobacterium tuberculosis (Mtb) that are constitutively expressed, overexpressed during growth, essential for survival, and highly conserved may be good vaccine targets if they induce the appropriate anti-Mtb Th1 immune response. In this context, stress response-related antigens of Mtb might serve as attractive targets for vaccine development as they are rapidly expressed and are up-regulated during Mtb infection in vivo. Our group recently demonstrated that GrpE, encoded by rv0351 as a cofactor of heat-shock protein 70 (HSP70) in the DnaK operon, is a novel immune activator that interacts with DCs to generate Th1-biased memory T cells in an antigen-specific manner. In this study, GrpE was evaluated as a subunit vaccine in comparison with the well-known HSP70 against the hyper-virulent Mtb Beijing K-strain. Both HSP70- and GrpE-specific effector/memory T cells expanded to a similar extent as those stimulated with ESAT-6 in the lung and spleen of Mtb-infected mice, but GrpE only produced a similar level of IFN-γ to that produced by ESAT-6 stimulation during the late phase and the early phase of Mtb K infection, indicating that GrpE is highly-well recognised by the host immune system as a T cell antigen. Mice immunised with the GrpE subunit vaccine displayed enhanced antigen-specific IFN-γ and serum IgG2c responses along with antigen-specific effector/memory T cell expansion in the lungs. In addition, GrpE-immunisation markedly induced multifunctional Th1-type CD4+ T cells co-expressing IFN-γ, TNF-α, and IL-2 in the lungs of Mtb K-infected mice, whereas HSP70-immunisation induced mixed Th1/Th2 immune responses. GrpE-immunisation conferred a more significant protective effect than that of HSP70-immunisation in terms of bacterial reduction and improved inflammation, accompanied by the remarkable persistence of GrpE-specific multifunctional CD4+ T cells. These results suggest that GrpE is an excellent vaccine antigen component for the development of a multi-antigenic Mtb subunit vaccine by generating Th1-biased memory T cells with multifunctional capacity, and confers durable protection against the highly virulent Mtb K.
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Affiliation(s)
- Woo Sik Kim
- Department of Microbiology, Institute for Immunology and Immunological Disease, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea.,Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup, South Korea
| | - Jong-Seok Kim
- Department of Microbiology, Institute for Immunology and Immunological Disease, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea.,Myunggok Medical Research Institute, College of Medicine, Konyang University, Daejeon, South Korea
| | - Hong Min Kim
- Department of Microbiology, Institute for Immunology and Immunological Disease, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea
| | - Kee Woong Kwon
- Department of Microbiology, Institute for Immunology and Immunological Disease, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea
| | - Seok-Yong Eum
- Division of Immunopathology and Cellular Immunology, International Tuberculosis Research Center, Changwon, South Korea
| | - Sung Jae Shin
- Department of Microbiology, Institute for Immunology and Immunological Disease, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul, South Korea.
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8
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Prosser G, Brandenburg J, Reiling N, Barry CE, Wilkinson RJ, Wilkinson KA. The bacillary and macrophage response to hypoxia in tuberculosis and the consequences for T cell antigen recognition. Microbes Infect 2016; 19:177-192. [PMID: 27780773 PMCID: PMC5335906 DOI: 10.1016/j.micinf.2016.10.001] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 10/06/2016] [Indexed: 12/11/2022]
Abstract
Mycobacterium tuberculosis is a facultative anaerobe and its characteristic pathological hallmark, the granuloma, exhibits hypoxia in humans and in most experimental models. Thus the host and bacillary adaptation to hypoxia is of central importance in understanding pathogenesis and thereby to derive new drug treatments and vaccines.
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Affiliation(s)
- Gareth Prosser
- Tuberculosis Research Section, Laboratory of Clinical Infectious Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, MD, 20892, United States
| | - Julius Brandenburg
- Microbial Interface Biology, Priority Research Area Infections, Forschungszentrum Borstel, Leibniz Center for Medicine and Biosciences, Parkallee 1-40, D-23845, Borstel, Germany
| | - Norbert Reiling
- Microbial Interface Biology, Priority Research Area Infections, Forschungszentrum Borstel, Leibniz Center for Medicine and Biosciences, Parkallee 1-40, D-23845, Borstel, Germany; German Center for Infection Research (DZIF), Partner Site Hamburg-Borstel-Lübeck, Borstel, Germany
| | - Clifton Earl Barry
- Tuberculosis Research Section, Laboratory of Clinical Infectious Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, MD, 20892, United States; Clinical Infectious Diseases Research Initiative, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, South Africa
| | - Robert J Wilkinson
- Clinical Infectious Diseases Research Initiative, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, South Africa; The Francis Crick Institute, London, NW1 2AT, United Kingdom; Department of Medicine, Imperial College, London, W2 1PG, United Kingdom.
| | - Katalin A Wilkinson
- Clinical Infectious Diseases Research Initiative, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, 7925, South Africa; The Francis Crick Institute, London, NW1 2AT, United Kingdom
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9
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Parijat P, Batra JK. Role of DnaK in HspR-HAIR interaction of Mycobacterium tuberculosis. IUBMB Life 2015; 67:816-27. [PMID: 26442450 DOI: 10.1002/iub.1438] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 09/17/2015] [Indexed: 01/17/2023]
Abstract
Heat shock proteins (Hsps) are a highly conserved family of proteins. The regulation of expression of Hsps in Mycobacterium tuberculosis, is regulated both positively and negatively by alternate sigma factors and transcriptional DNA repressors, respectively. HspR is a negative regulator of expression of hsps, DnaK, ClpB, and Acr2 in M. tuberculosis. In this study, we expressed the M. tuberculosis HspR (MtHspR) in E. coli, and functionally characterized it. MtHspR independently bound to its putative cognate DNA, the HAIR element. MtHspR was found to exist in a dynamic mixture of dimeric and monomeric protein and presence of salt led to the formation of trimers which lacked the DNA binding activity. MtHspR was found to be heat stable with a Tm of 66°C. HspR-HAIR binding was stable upto 60°C suggesting that MtHspR is not the heat stress sensor. Mycobacterial DnaK was found to interact directly with MtHspR-HAIR complex in vitro in an ATP independent manner. The DnaK-HspR-HAIR binding pattern altered at high temperatures in the presence of aggregated α-casein substrate, suggesting that DnaK may indirectly be responding to heat stress in a feedback loop mechanism.
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Affiliation(s)
- Priyanka Parijat
- Immunochemistry Laboratory, National Institute of Immunology, New Delhi, India
| | - Janendra K Batra
- Immunochemistry Laboratory, National Institute of Immunology, New Delhi, India.,Centre for Molecular Medicine, National Institute of Immunology, New Delhi, India
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10
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Chim N, Owens CP, Contreras H, Goulding CW. Withdrawn. Infect Disord Drug Targets 2012:CDTID-EPUB-20121116-2. [PMID: 23167715 PMCID: PMC3695056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Withdrawn by the publisher.
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Affiliation(s)
- Nicholas Chim
- Department of Molecular Biology and Biochemistry, University of California, Irvine CA 92697, USA
| | - Cedric P. Owens
- Department of Molecular Biology and Biochemistry, University of California, Irvine CA 92697, USA
| | - Heidi Contreras
- Department of Molecular Biology and Biochemistry, University of California, Irvine CA 92697, USA
| | - Celia W. Goulding
- Department of Molecular Biology and Biochemistry, University of California, Irvine CA 92697, USA
- Department of Pharmaceutical Sciences, University of California, Irvine CA 92697, USA
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11
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Forrellad MA, Klepp LI, Gioffré A, Sabio y García J, Morbidoni HR, de la Paz Santangelo M, Cataldi AA, Bigi F. Virulence factors of the Mycobacterium tuberculosis complex. Virulence 2012; 4:3-66. [PMID: 23076359 PMCID: PMC3544749 DOI: 10.4161/viru.22329] [Citation(s) in RCA: 368] [Impact Index Per Article: 30.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The Mycobacterium tuberculosis complex (MTBC) consists of closely related species that cause tuberculosis in both humans and animals. This illness, still today, remains to be one of the leading causes of morbidity and mortality throughout the world. The mycobacteria enter the host by air, and, once in the lungs, are phagocytated by macrophages. This may lead to the rapid elimination of the bacillus or to the triggering of an active tuberculosis infection. A large number of different virulence factors have evolved in MTBC members as a response to the host immune reaction. The aim of this review is to describe the bacterial genes/proteins that are essential for the virulence of MTBC species, and that have been demonstrated in an in vivo model of infection. Knowledge of MTBC virulence factors is essential for the development of new vaccines and drugs to help manage the disease toward an increasingly more tuberculosis-free world.
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Kumar S, Badireddy S, Pal K, Sharma S, Arora C, Garg SK, Alam MS, Agrawal P, Anand GS, Swaminathan K. Interaction of Mycobacterium tuberculosis RshA and SigH is mediated by salt bridges. PLoS One 2012; 7:e43676. [PMID: 22937074 PMCID: PMC3427169 DOI: 10.1371/journal.pone.0043676] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 07/26/2012] [Indexed: 01/07/2023] Open
Abstract
The alternate sigma factor sigH of Mycobacterium tuberculosis is expressed under stress and acts as a major regulator of several genes, including some other sigma factors and redox systems. While it is auto-regulated by its own promoter at the transcriptional level, its regulation at the post-translational level is through its cognate protein, an anti-sigma factor, RshA. Hither before RshA was believed to be a zinc-associated anti-sigma factor (ZAS) and the binding of RshA to SigH is redox dependent. Here, we show that RshA coordinates a [2Fe-2S] cluster using cysteines as ligands and native RshA has more affinity to [2Fe-2S] cluster than to zinc. Furthermore, we used amide hydrogen deuterium exchange mass spectrometry (HDX-MS), followed by site-directed mutagenesis in SigH and RshA, to elucidate the interaction mechanism of RshA and SigH and the potential role of metal ion clustering in SigH regulation. Three regions in SigH, comprising of residues 1-25, 58-69, 90-111, 115-132 and 157-196 and residues 35-57 of RshA show decreased deuterium exchange and reflect decreased solvent accessibility upon complexation with SigH. Of the three RshA mutants, created based on the HDX results, the RsHA E37A mutant shows stronger interaction with SigH, relative to WT RshA, while the H49A mutant abolishes interactions and the C(53)XXC(56)AXXA mutant has no effect on complexation with SigH. The D22A, D160A and E162 SigH mutants show significantly decreased binding to RshA and the E168A mutant completely abolished interactions with RshA, indicating that the SigH-RshA interaction is mediated by salt bridges. In addition, SigH-RshA interaction does not require clustering of metal ions. Based on our results, we propose a molecular model of the SigH-RshA interaction.
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Affiliation(s)
- Shiva Kumar
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Suguna Badireddy
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Kuntal Pal
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Shikha Sharma
- Institute of Microbial Technology, CSIR, Sector 39-A, Chandigarh, India
| | - Chandni Arora
- Institute of Microbial Technology, CSIR, Sector 39-A, Chandigarh, India
| | - Saurabh K. Garg
- Institute of Microbial Technology, CSIR, Sector 39-A, Chandigarh, India
| | | | - Pushpa Agrawal
- Institute of Microbial Technology, CSIR, Sector 39-A, Chandigarh, India
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Carroll P, Waddell SJ, Butcher PD, Parish T. Methionine sulfoximine resistance in Mycobacterium tuberculosis is due to a single nucleotide deletion resulting in increased expression of the major glutamine synthetase, GlnA1. Microb Drug Resist 2012; 17:351-5. [PMID: 21875360 DOI: 10.1089/mdr.2010.0125] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We investigated the effect of methionine sulfoximine (MetSox), a potent inhibitor of glutamine synthetase, on Mycobacterium tuberculosis. M. tuberculosis encodes four glutamine synthetases, of which MetSox targets the type I enzyme encoded by glnA1. Transcriptional profiling revealed that glutamate synthetase (gltB) and a type II glutamine synthetase (glnA3) were induced after exposure to MetSox. In addition, we observed a high rate (10(-5)) of spontaneous resistance to MetSox. All resistant strains had a single-nucleotide deletion in the 5' region of glnA1, and Western analysis revealed that GlnA1 expression was increased in resistant as compared with sensitive strains. These data show that M. tuberculosis can respond to the effect of MetSox inhibition either by up-regulation of GlnA3 or by GlnA1. The high frequency of resistance suggests that MetSox and other compounds specifically targeting GlnA1 are not likely to become successful anti-mycobacterial agents.
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Affiliation(s)
- Paul Carroll
- Barts & The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
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Dutta NK, Mehra S, Martinez AN, Alvarez X, Renner NA, Morici LA, Pahar B, MacLean AG, Lackner AA, Kaushal D. The stress-response factor SigH modulates the interaction between Mycobacterium tuberculosis and host phagocytes. PLoS One 2012; 7:e28958. [PMID: 22235255 PMCID: PMC3250399 DOI: 10.1371/journal.pone.0028958] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Accepted: 11/17/2011] [Indexed: 12/31/2022] Open
Abstract
The Mycobacterium tuberculosis stress response factor SigH plays a crucial role in modulating the pathogen's response to heat, oxidative-stress, envelope damage and hypoxia. We hypothesized that the lack of this key stress response factor would alter the interaction between the pathogen and its host cells. We compared the interaction of Mtb, Mtb:Δ-sigH and a strain where the mutation had been genetically complemented (Mtb: Δ-sigH:CO) with primary rhesus macaque bone marrow derived macrophages (Rh-BMDMs). The expression of numerous inducible and homeostatic (CCL) β-chemokines and several apoptotic markers was induced to higher levels in the cells infected with Mtb:Δ-sigH, relative to Mtb or the complemented strain. The differential expression of these genes manifested into functional differences in chemotaxis and apoptosis in cells infected with these two strains. The mutant strain also exhibited reduced late-stage survival in Rh-BMDMs. We hypothesize that the product of one or more SigH-dependent genes may modulate the innate interaction of Mtb with host cells, effectively reducing the chemokine-mediated recruitment of immune effector cells, apoptosis of infected monocytes and enhancing the long-term survival and replication of the pathogen in this milieu The significantly higher induction of Prostaglandin Synthetase 2 (PTGS2 or COX2) in Rh-BMDMs infected with Mtb relative to Mtb: Δ-sigH may explain reduced apoptosis in Mtb-infected cells, as PTGS2 is known to inhibit p53-dependent apoptosis.The SigH-regulon modulates the innate interaction of Mtb with host phagocytes, perhaps as part of a strategy to limit its clearance and prolong its survival. The SigH regulon appears to be required to modulate innate immune responses directed against Mtb.
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Affiliation(s)
- Noton K. Dutta
- Divisions of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, Louisiana, United States of America
| | - Smriti Mehra
- Divisions of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, Louisiana, United States of America
| | - Alejandra N. Martinez
- Divisions of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, Louisiana, United States of America
| | - Xavier Alvarez
- Divisions of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana, United States of America
| | - Nicole A. Renner
- Divisions of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana, United States of America
| | - Lisa A. Morici
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Bapi Pahar
- Divisions of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana, United States of America
| | - Andrew G. MacLean
- Divisions of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana, United States of America
| | - Andrew A. Lackner
- Divisions of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana, United States of America
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Deepak Kaushal
- Divisions of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, Louisiana, United States of America
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
- * E-mail:
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Hingley-Wilson SM, Lougheed KEA, Ferguson K, Leiva S, Williams HD. Individual Mycobacterium tuberculosis universal stress protein homologues are dispensable in vitro. Tuberculosis (Edinb) 2010; 90:236-44. [PMID: 20541977 PMCID: PMC2914252 DOI: 10.1016/j.tube.2010.03.013] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 03/16/2010] [Accepted: 03/31/2010] [Indexed: 01/25/2023]
Abstract
Mycobacterium tuberculosis has 10 universal stress proteins, whose function is unknown. However, proteomic and transcriptomic analyses have shown that a number of usp genes are significantly upregulated under hypoxic conditions and in response to nitric oxide and carbon monoxide, as well as during M. tuberculosis infection of macrophage cell lines. Six of these USPs are part of the DosR regulon and this, along with their expression pattern and the phenotypes of usp mutants in other bacterial species, suggests a potential role in the persistence and/or intracellular survival of Mtb. Knock-out mutants of individual usp genes encoding the USPs Rv1996, Rv2005c, Rv2026c and Rv2028c were generated and their growth and survival under hypoxic and other stress conditions examined. Although the majority of usp genes are highly induced in hypoxic conditions, mutation did not affect the long term survival of Mtb under these conditions, or in response to a range of stress conditions chosen to represent the environmental onslaughts experienced by the bacillus during an infection, nor during infection of mouse and human - derived macrophage cell lines. The possibility remains that these USPs are functionally redundant in Mtb.
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Affiliation(s)
- S M Hingley-Wilson
- Department of Life Sciences, Imperial College London, London SW7 2AZ, UK
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17
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Influence of tigecycline on expression of virulence factors in biofilm-associated cells of methicillin-resistant Staphylococcus aureus. Antimicrob Agents Chemother 2009; 54:380-7. [PMID: 19858261 DOI: 10.1128/aac.00155-09] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) infections are complicated by the ability of the organism to grow in surface-adhered biofilms on a multitude of abiotic and biological surfaces. These multicellular communities are notoriously difficult to eradicate with antimicrobial therapy. Cells within the biofilm may be exposed to a sublethal concentration of the antimicrobial due to the metabolic and phenotypic diversity of the biofilm-associated cells or the protection offered by the biofilm structure. In the present study, the influence of a sublethal concentration of tigecycline on biofilms formed by an epidemic MRSA-16 isolate was investigated by transcriptome analysis. In the presence of the drug, 309 genes were upregulated and 213 genes were downregulated by more than twofold in comparison to the levels of gene regulation detected for the controls not grown in the presence of the drug. Microarray data were validated by real-time reverse transcription-PCR and phenotypic assays. Tigecycline altered the expression of a number of genes encoding proteins considered to be crucial for the virulence of S. aureus. These included the reduced expression of icaC, which is involved in polysaccharide intercellular adhesin production and biofilm development; the upregulation of fnbA, clfB, and cna, which encode adhesins which attach to human proteins; and the downregulation of the cap genes, which mediate the synthesis of the capsule polysaccharide. The expression of tst, which encodes toxic shock syndrome toxin 1 (TSST-1), was also significantly reduced; and an assay performed to quantify TSST-1 showed that the level of toxin production by cells treated with tigecycline decreased by 10-fold (P < 0.001) compared to the level of production by untreated control cells. This study suggests that tigecycline may reduce the expression of important virulence factors in S. aureus and supports further investigation to determine whether it could be a useful adjunct to therapy for the treatment of biofilm-mediated infections.
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Aravindhan V, Christy AJ, Roy S, Ajitkumar P, Narayanan PR, Narayanan S. Mycobacterium tuberculosis groEpromoter controls the expression of the bicistronicgroESL1operon and shows differential regulation under stress conditions. FEMS Microbiol Lett 2009; 292:42-9. [DOI: 10.1111/j.1574-6968.2008.01465.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Lu SE, Wang N, Wang J, Chen ZJ, Gross DC. Oligonucleotide microarray analysis of the salA regulon controlling phytotoxin production by Pseudomonas syringae pv. syringae. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2005; 18:324-333. [PMID: 15828684 DOI: 10.1094/mpmi-18-0324] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The salA gene is a key regulatory element for syringomycin production by Pseudomonas syringae pv. syringae and encodes a member of the LuxR regulatory protein family. Previous studies revealed that salA, a member of the GacS/GacA signal transduction system, was required for bacterial virulence, syringomycin production, and expression of the syrB1 synthetase gene. To define the SalA regulon, the spotted oligonucleotide microarray was constructed using gene-specific 70-mer oligonucleotides of all open reading frames (ORFs) predicted in the syringomycin (syr) and syringopeptin (syp) gene clusters along with representative genes important to bacterial virulence, growth, and survival. The microarray containing 95 oligos was used to analyze transcriptional changes in a salA mutant (B301DSL07) and its wild-type strain, B301D. Expression of 16 genes was significantly higher (> twofold) in B301D than in the salA mutant; the maximum change in expression was 15-fold for some toxin biosynthesis genes. Except for the sylD synthetase gene for syringolin production, all ORFs controlled by SalA were located in the syr-syp genomic island and were associated with biosynthesis, secretion, and regulation of syringomycin and syringopeptin. The positive regulatory effect of SalA on transcription of sypA, syrB1, syrC, and sylD was verified by reporter fusions or real-time polymerase chain reaction analysis. None of the genes or ORFs was significantly down-regulated by the salA gene. These results demonstrated that a subgenomic oligonucleotide microarray is a powerful tool for defining the SalA regulon and its relationship to other genes important to plant pathogenesis.
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Affiliation(s)
- Shi-En Lu
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX 77843, USA
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