1
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Harrison B, Raju D, Garmory HS, Brett MM, Titball RW, Sarker MR. Retraction for Harrison et al., "Molecular Characterization of Clostridium perfringens Isolates from Humans with Sporadic Diarrhea: Evidence for Transcriptional Regulation of the Beta2-Toxin-Encoding Gene". Appl Environ Microbiol 2024; 90:e0025924. [PMID: 38606962 DOI: 10.1128/aem.00259-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2024] Open
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2
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Waters M, Savoie A, Garmory HS, Bueschel D, Popoff MR, Songer JG, Titball RW, McClane BA, Sarker MR. Retraction for Waters et al., "Genotyping and Phenotyping of Beta2-Toxigenic Clostridium perfringens Fecal Isolates Associated with Gastrointestinal Diseases in Piglets. J Clin Microbiol 2024; 62:e0023724. [PMID: 38606969 PMCID: PMC11077954 DOI: 10.1128/jcm.00237-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2024] Open
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3
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Bloom DE, Titball RW, Carapetis J. Strep A: challenges, opportunities, vaccine-based solutions and economics. NPJ Vaccines 2024; 9:81. [PMID: 38641630 PMCID: PMC11031572 DOI: 10.1038/s41541-024-00864-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/21/2024] Open
Affiliation(s)
- David E Bloom
- Harvard T.H. Chan School of Public Health, Boston, MA, USA.
| | | | - Jonathan Carapetis
- Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia, Perth, WA, Australia.
- Perth Children's Hospital, Perth, WA, Australia.
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4
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Titball RW. The Molecular Architecture and Mode of Action of Clostridium perfringens ε-Toxin. Toxins (Basel) 2024; 16:180. [PMID: 38668605 PMCID: PMC11053738 DOI: 10.3390/toxins16040180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2024] [Revised: 03/31/2024] [Accepted: 04/02/2024] [Indexed: 04/29/2024] Open
Abstract
Clostridium perfringens ε-toxin has long been associated with a severe enterotoxaemia of livestock animals, and more recently, was proposed to play a role in the etiology of multiple sclerosis in humans. The remarkable potency of the toxin has intrigued researchers for many decades, who suggested that this indicated an enzymatic mode of action. Recently, there have been major breakthroughs by finding that it is a pore-forming toxin which shows exquisite specificity for cells bearing the myelin and lymphocyte protein (MAL) receptor. This review details the molecular structures of the toxin, the evidence which identifies MAL as the receptor and the possible roles of other cell membrane components in toxin binding. The information on structure and mode of action has allowed the functions of individual amino acids to be investigated and has led to the creation of mutants with reduced toxicity that could serve as vaccines. In spite of this progress, there are still a number of key questions around the mode of action of the toxin which need to be further investigated.
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5
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Titball RW, Bernstein DI, Fanget NVJ, Hall RA, Longet S, MacAry PA, Rupp RE, van Gils M, von Messling V, Walker DH, Barrett ADT. Progress with COVID vaccine development and implementation. NPJ Vaccines 2024; 9:69. [PMID: 38561358 PMCID: PMC10985065 DOI: 10.1038/s41541-024-00867-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Accepted: 03/22/2024] [Indexed: 04/04/2024] Open
Affiliation(s)
| | - David I Bernstein
- Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH, USA
| | | | - Roy A Hall
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD, Australia
| | - Stephanie Longet
- CIRI - Centre International de Recherche en Infectiologie, Team GIMAP, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, CIC 1408 Vaccinology, F42023, Saint-Etienne, France
| | - Paul A MacAry
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Richard E Rupp
- Department of Pediatrics, University of Texas Medical Branch, Galveston, TX, USA
| | - Marit van Gils
- Department of Medical Microbiology and Infection Prevention, Amsterdam Institute for Immunology and Infectious Diseases, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | | | - David H Walker
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA
| | - Alan D T Barrett
- Sealy Institute for Vaccine Sciences and Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA
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6
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Titball RW, Lewis N, Nicholas R. Is Clostridium perfringens epsilon toxin associated with multiple sclerosis? Mult Scler 2023; 29:1057-1063. [PMID: 37480283 PMCID: PMC10413780 DOI: 10.1177/13524585231186899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/29/2023] [Accepted: 06/06/2023] [Indexed: 07/23/2023]
Abstract
Clostridium perfringens epsilon toxin is associated with enterotoxaemia in livestock. More recently, it is proposed to play a role in multiple sclerosis (MS) in humans. Compared to matched controls, strains of C. perfringens which produce epsilon toxin are significantly more likely to be isolated from the gut of MS patients and at significantly higher levels; similarly, sera from MS patients are significantly more likely to contain antibodies to epsilon toxin. Epsilon toxin recognises the myelin and lymphocyte (MAL) protein receptor, damaging the blood-brain barrier and brain cells expressing MAL. In the experimental autoimmune encephalomyelitis model of MS, the toxin enables infiltration of immune cells into the central nervous system, inducing an MS-like disease. These studies provide evidence that epsilon toxin plays a role in MS, but do not yet fulfil Koch's postulates in proving a causal role.
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Affiliation(s)
| | | | - Richard Nicholas
- Division of Brain Sciences, Department of Medicine, Imperial College London, London, UK
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7
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de Mello VVC, Placa AJV, Lee DAB, Franco EO, Lima L, Teixeira MMG, Hemsley C, Titball RW, Machado RZ, André MR. Molecular detection of blood-borne agents in vampire bats from Brazil, with the first molecular evidence of Neorickettsia sp. in Desmodus rotundus and Diphylla ecaudata. Acta Trop 2023; 244:106945. [PMID: 37207993 DOI: 10.1016/j.actatropica.2023.106945] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 04/25/2023] [Accepted: 05/14/2023] [Indexed: 05/21/2023]
Abstract
Bats (Mammalia, Chiroptera) represent the second largest group of mammals. Due to their ability to fly and adapt and colonize different niches, bats act as reservoirs of several potentially zoonotic pathogens. In this context, the present work aimed to investigate, using molecular techniques, the occurrence of blood-borne agents (Anaplasmataceae, Coxiella burnetii, hemoplasmas, hemosporidians and piroplasmids) in 198 vampire bats sampled in different regions of Brazil and belonging to the species Desmodus rotundus (n=159), Diphylla ecaudata (n=31) and Diaemus youngii (n=8). All vampire bats liver samples were negative in PCR assays for Ehrlichia spp., Anaplasma spp., piroplasmids, hemosporidians and Coxiella burnetii. However, Neorickettsia sp. was detected in liver samples of 1.51% (3/198) through nested PCR based on the 16S rRNA gene in D. rotundus and D. ecaudata. This is the first study to report Neorickettsia sp. in vampire bats. Hemoplasmas were detected in 6.06% (12/198) of the liver samples using a PCR based on the 16S rRNA gene. The two 16S rRNA sequences obtained from hemoplasmas were closely related to sequences previously identified in vampire and non-hematophagous bats from Belize, Peru and Brazil. The genotypic analysis identified a high diversity of bat-associated hemoplasma genotypes from different regions of the world, emphasizing the need for studies on this subject, in order to better understand the mechanisms of co-evolution between this group of bacteria and their vertebrate hosts. The role of neotropical bat-associated Neorickettsia sp. and bats from Brazilian in the biological cycle of such agent warrant further investigation.
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Affiliation(s)
- Victória Valente Califre de Mello
- Postgraduate Program in Agricultural Microbiology, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, SP, Brazil; Vector-Borne Bioagents Laboratory (VBBL), Department of Pathology, Reproduction and One Health, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, SP, Brazil
| | - Ana Julia Vidal Placa
- Vector-Borne Bioagents Laboratory (VBBL), Department of Pathology, Reproduction and One Health, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, SP, Brazil
| | - Daniel Antonio Braga Lee
- Vector-Borne Bioagents Laboratory (VBBL), Department of Pathology, Reproduction and One Health, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, SP, Brazil
| | - Eliz Oliveira Franco
- Vector-Borne Bioagents Laboratory (VBBL), Department of Pathology, Reproduction and One Health, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, SP, Brazil
| | - Luciana Lima
- Laboratory of Trypanosomatids Taxonomy and Phylogeny, Department of Parasitology, Institute of Biomedical Sciences II, University of Sao Paulo, São Paulo, SP, Brazil
| | - Marta M G Teixeira
- Laboratory of Trypanosomatids Taxonomy and Phylogeny, Department of Parasitology, Institute of Biomedical Sciences II, University of Sao Paulo, São Paulo, SP, Brazil
| | - Claudia Hemsley
- Department of Biosciences, College of Life and Environmental Sciences - Biosciences, University of Exeter, Exeter, UK
| | - Richard W Titball
- Department of Biosciences, College of Life and Environmental Sciences - Biosciences, University of Exeter, Exeter, UK
| | - Rosangela Zacarias Machado
- Vector-Borne Bioagents Laboratory (VBBL), Department of Pathology, Reproduction and One Health, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, SP, Brazil
| | - Marcos Rogério André
- Vector-Borne Bioagents Laboratory (VBBL), Department of Pathology, Reproduction and One Health, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, SP, Brazil.
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8
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Hemsley CM, Essex-Lopresti A, Chisnall T, Millar M, Neale S, Reichel R, Norville IH, Titball RW. MLVA and com1 genotyping of Coxiella burnetii in farmed ruminants in Great Britain. Vet Microbiol 2023; 277:109629. [PMID: 36535174 DOI: 10.1016/j.vetmic.2022.109629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 09/15/2022] [Accepted: 12/07/2022] [Indexed: 12/13/2022]
Abstract
Coxiella burnetii, the causative agent of the zoonotic disease Q fever, has been shown to be endemic in Great Britain, but information on the prevailing genomic lineages or Genomic Groups (GGs) of Coxiella burnetii is limited. The aim of this study was to genotype C. burnetii isolates from infected farmed ruminants by Multiple Locus Variable Number Tandem Repeat Analysis (MLVA) and identify their associated Genomic Group. A total of 51 Coxiella-containing abortion samples from farmed ruminants (sheep, goats, and cattle), which were collected in Great Britain during 2013-2018, were included in the study, 34 of which returned a C. burnetii MLVA genotype. All bovine samples (n = 18), 5/7 of the ovine samples, and 3/9 of the caprine samples belonged to an MLVA cluster which we could link to the MST20 genotype of GG III, whereas 6/9 of the caprine samples and 2/7 of the ovine samples belonged to MLVA clusters which we could link to the MST33 or MST32 genotypes of GG II (7 vs 1 sample(s), respectively). We also noted that the Coxiella-specific com1 gene contained unique mutations that could genomotype isolates, i.e. assign them to a Genomic Group. In conclusion, both goats and sheep in Great Britain (from 2014 onward) were found to carry the same MLVA genotypes (MST33-like; GG II) that were linked to a human Q fever outbreak in the Netherlands. This knowledge in combination with the usage of genotyping/genomotyping methods should prove useful in future surveillance programs and in the management of outbreaks.
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Affiliation(s)
- Claudia M Hemsley
- College of Life and Environmental Sciences, Biosciences, University of Exeter, Exeter, UK.
| | | | | | | | - Sue Neale
- Animal and Plant Health Agency, Penrith, UK.
| | | | - Isobel H Norville
- College of Life and Environmental Sciences, Biosciences, University of Exeter, Exeter, UK; Defence Science and Technology Laboratory, Porton Down, Salisbury, UK.
| | - Richard W Titball
- College of Life and Environmental Sciences, Biosciences, University of Exeter, Exeter, UK.
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9
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Harrison J, Nelson K, Morcrette H, Morcrette C, Preston J, Helmer L, Titball RW, Butler CS, Wagley S. The increased prevalence of Vibrio species and the first reporting of Vibrio jasicida and Vibrio rotiferianus at UK shellfish sites. Water Res 2022; 211:117942. [PMID: 35042073 PMCID: PMC8841665 DOI: 10.1016/j.watres.2021.117942] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 11/18/2021] [Accepted: 12/05/2021] [Indexed: 05/31/2023]
Abstract
Warming sea-surface temperature has led to an increase in the prevalence of Vibrio species in marine environments. This can be observed particularly in temperate regions where conditions for their growth has become more favourable. The increased prevalence of pathogenic Vibrio species has resulted in a worldwide surge of Vibriosis infections in human and aquatic animals. This study uses sea-surface temperature data around the English and Welsh coastlines to identify locations where conditions for the presence and growth of Vibrio species is favourable. Shellfish samples collected from three locations that were experiencing an increase in sea-surface temperature were found to be positive for the presence of Vibrio species. We identified important aquaculture pathogens Vibrio rotiferianus and Vibrio jasicida from these sites that have not been reported in UK waters. We also isolated human pathogenic Vibrio species including V. parahaemolyticus from these sites. This paper reports the first isolation of V. rotiferianus and V. jasicida from UK shellfish and highlights a growing diversity of Vibrio species inhabiting British waters.
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Affiliation(s)
- Jamie Harrison
- Biosciences, College of life and Environmental Sciences, University of Exeter, Devon, Exeter EX4 4QD, UK
| | - Kathryn Nelson
- Sussex Inshore Fisheries and Conservation Authority, 12a Riverside Business Centre, Brighton Road, Shoreham BN43 6RE, UK
| | - Helen Morcrette
- Biosciences, College of life and Environmental Sciences, University of Exeter, Devon, Exeter EX4 4QD, UK
| | | | - Joanne Preston
- Institute of Marine Sciences, School of Biological Sciences, University of Portsmouth PO4 9LY, UK
| | - Luke Helmer
- Institute of Marine Sciences, School of Biological Sciences, University of Portsmouth PO4 9LY, UK; Blue Marine Foundation, Somerset House, London WC2R 1LA, UK
| | - Richard W Titball
- Biosciences, College of life and Environmental Sciences, University of Exeter, Devon, Exeter EX4 4QD, UK
| | - Clive S Butler
- Biosciences, College of life and Environmental Sciences, University of Exeter, Devon, Exeter EX4 4QD, UK
| | - Sariqa Wagley
- Biosciences, College of life and Environmental Sciences, University of Exeter, Devon, Exeter EX4 4QD, UK.
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10
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Kovacs-Simon A, Metters G, Norville I, Hemsley C, Titball RW. Coxiella burnetii replicates in Galleria mellonella hemocytes and transcriptome mapping reveals in vivo regulated genes. Virulence 2021; 11:1268-1278. [PMID: 32970966 PMCID: PMC7549970 DOI: 10.1080/21505594.2020.1819111] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Larvae of the greater wax moth (Galleria mellonella) are susceptible to infection with C. burnetii, an obligate intracellular bacterial pathogen. We show that bacteria are found in hemocytes after infection, and occupy vacuoles which are morphologically similar to Coxiella-containing vacuoles seen in infected mammalian phagocytes. We characterized the infection by transcriptome profiling of bacteria isolated from the hemocytes of infected larvae and identified 46 highly upregulated genes. The encoded proteins are predicted to be involved in translation, LPS biosynthesis, biotin synthesis, scavenging of reactive oxygen species, and included a T4SS effector and 30 hypothetical proteins. Some of these genes had previously been shown to be upregulated in buffalo green monkey (BGM) cells or in mice, whilst others appear to be regulated in a host-specific manner. Altogether, our results demonstrate the value of the G. mellonella model to study intracellular growth and identify potential virulence factors of C. burnetii.
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Affiliation(s)
- Andrea Kovacs-Simon
- College of Life and Environmental Sciences - Biosciences, University of Exeter , Exeter, UK
| | - Georgie Metters
- College of Life and Environmental Sciences - Biosciences, University of Exeter , Exeter, UK
| | - Isobel Norville
- CBR Division, Defence Science and Technology Laboratory , Porton Down,Salisbury, UK
| | - Claudia Hemsley
- College of Life and Environmental Sciences - Biosciences, University of Exeter , Exeter, UK
| | - Richard W Titball
- College of Life and Environmental Sciences - Biosciences, University of Exeter , Exeter, UK
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11
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Abstract
Galleria mellonella larvae are increasingly used to study the mechanisms of virulence of microbial pathogens and to assess the efficacy of antimicrobials. The G. mellonella model can faithfully reproduce many aspects of microbial disease which are seen in mammals, and therefore allows a reduction in the use of mammals. The model is now being widely used by researchers in universities, research institutes and industry. An attraction of the model is the interaction between pathogen and host. Hemocytes are specialised phagocytic cells which resemble neutrophils in mammals and play a major role in the response of the larvae to infection. However, the detailed interactions of hemocytes with pathogens is poorly understood, and is complicated by the presence of different sub-populations of cells. We report here a method for the isolation of hemocytes from Galleria mellonella. A needle-stick injury of larvae, before harvesting, markedly increased the recovery of hemocytes in the hemolymph. The majority of the hemocytes recovered were granulocyte-like cells. The hemocytes survived for at least 7 days in culture at either 28°C or 37°C. Pre-treatment of larvae with antibiotics did not enhance the survival of the cultured hemocytes. Our studies highlight the importance of including sham injected, rather than un-injected, controls when the G. mellonella model is used to test antimicrobial compounds. Our method will now allow investigations of the interactions of microbial pathogens with insect hemocytes enhancing the value of G. mellonella as an alternative model to replace the use of mammals, and for studies on hemocyte biology.
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Affiliation(s)
- Nicola J. Senior
- College of Life and Environmental Sciences - Biosciences, University of Exeter, Exeter, Devon, EX4 4QD, UK
| | - Richard W. Titball
- College of Life and Environmental Sciences - Biosciences, University of Exeter, Exeter, Devon, EX4 4QD, UK,
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12
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Abstract
Galleria mellonella larvae are increasingly used to study the mechanisms of virulence of microbial pathogens and to assess the efficacy of antimicrobials. The G. mellonella model can faithfully reproduce many aspects of microbial disease which are seen in mammals, and therefore allows a reduction in the use of mammals. The model is now being widely used by researchers in universities, research institutes and industry. An attraction of the model is the interaction between pathogen and host. Hemocytes are specialised phagocytic cells which resemble neutrophils in mammals and play a major role in the response of the larvae to infection. However, the detailed interactions of hemocytes with pathogens is poorly understood, and is complicated by the presence of different sub-populations of cells. We report here a method for the isolation of hemocytes from Galleria mellonella. A needle-stick injury of larvae, before harvesting, markedly increased the recovery of hemocytes in the hemolymph. The majority of the hemocytes recovered were granulocyte-like cells. The hemocytes survived for at least 7 days in culture at either 28°C or 37°C. Pre-treatment of larvae with antibiotics did not enhance the survival of the cultured hemocytes. Our studies highlight the importance of including sham injected, rather than un-injected, controls when the G. mellonella model is used to test antimicrobial compounds. Our method will now allow investigations of the interactions of microbial pathogens with insect hemocytes enhancing the value of G. mellonella as an alternative model to replace the use of mammals, and for studies on hemocyte biology.
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Affiliation(s)
- Nicola J. Senior
- College of Life and Environmental Sciences - Biosciences, University of Exeter, Exeter, Devon, EX4 4QD, UK
| | - Richard W. Titball
- College of Life and Environmental Sciences - Biosciences, University of Exeter, Exeter, Devon, EX4 4QD, UK
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13
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Morcrette H, Kovacs-Simon A, Tennant RK, Love J, Wagley S, Yang ZR, Studholme DJ, Soyer OS, Champion OL, Butler CS, Titball RW. Campylobacter jejuni 11168H Exposed to Penicillin Forms Persister Cells and Cells With Altered Redox Protein Activity. Front Cell Infect Microbiol 2020; 10:565975. [PMID: 33194805 PMCID: PMC7641608 DOI: 10.3389/fcimb.2020.565975] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 09/11/2020] [Indexed: 12/13/2022] Open
Abstract
The formation of persister cells is one mechanism by which bacteria can survive exposure to environmental stresses. We show that Campylobacter jejuni 11168H forms persister cells at a frequency of 10−3 after exposure to 100 × MIC of penicillin G for 24 h. Staining the cell population with a redox sensitive fluorescent dye revealed that penicillin G treatment resulted in the appearance of a population of cells with increased fluorescence. We present evidence, to show this could be a consequence of increased redox protein activity in, or associated with, the electron transport chain. These data suggest that a population of penicillin G treated C. jejuni cells could undergo a remodeling of the electron transport chain in order to moderate membrane hyperpolarization and intracellular alkalization; thus reducing the antibiotic efficacy and potentially assisting in persister cell formation.
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Affiliation(s)
- Helen Morcrette
- College of Life and Environmental Sciences-Biosciences, University of Exeter, Exeter, United Kingdom
| | - Andrea Kovacs-Simon
- College of Life and Environmental Sciences-Biosciences, University of Exeter, Exeter, United Kingdom
| | - Richard K Tennant
- College of Life and Environmental Sciences-Biosciences, University of Exeter, Exeter, United Kingdom
| | - John Love
- College of Life and Environmental Sciences-Biosciences, University of Exeter, Exeter, United Kingdom
| | - Sariqa Wagley
- College of Life and Environmental Sciences-Biosciences, University of Exeter, Exeter, United Kingdom
| | - Zheng R Yang
- College of Life and Environmental Sciences-Biosciences, University of Exeter, Exeter, United Kingdom
| | - David J Studholme
- College of Life and Environmental Sciences-Biosciences, University of Exeter, Exeter, United Kingdom
| | - Orkun S Soyer
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Olivia L Champion
- College of Life and Environmental Sciences-Biosciences, University of Exeter, Exeter, United Kingdom
| | - Clive S Butler
- College of Life and Environmental Sciences-Biosciences, University of Exeter, Exeter, United Kingdom
| | - Richard W Titball
- College of Life and Environmental Sciences-Biosciences, University of Exeter, Exeter, United Kingdom
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14
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Abstract
Trehalose is a disaccharide of two D-glucose molecules linked by a glycosidic linkage, which plays both structural and functional roles in bacteria. Trehalose can be synthesized and degraded by several pathways, and induction of trehalose biosynthesis is typically associated with exposure to abiotic stress. The ability of trehalose to protect against abiotic stress has been exploited to stabilize a range of bacterial vaccines. More recently, there has been interest in the role of this molecule in microbial virulence. There is now evidence that trehalose or trehalose derivatives play important roles in virulence of a diverse range of Gram-positive and Gram-negative pathogens of animals or plants. Trehalose and/or trehalose derivatives can play important roles in host colonization and growth in the host, and can modulate the interactions with host defense mechanisms. However, the roles are typically pathogen-specific. These findings suggest that trehalose metabolism may be a target for novel pathogen-specific rather than broad spectrum interventions.
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Affiliation(s)
- Muthita Vanaporn
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University , Bangkok, Thailand
| | - Richard W Titball
- College of Life and Environmental Sciences, University of Exeter , Exeter, UK
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15
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Jitprasutwit S, Jitprasutwit N, Hemsley CM, Onlamoon N, Withatanung P, Muangsombut V, Vattanaviboon P, Stevens JM, Ong C, Stevens MP, Titball RW, Korbsrisate S. Identification of Burkholderia pseudomallei Genes Induced During Infection of Macrophages by Differential Fluorescence Induction. Front Microbiol 2020; 11:72. [PMID: 32153515 PMCID: PMC7047822 DOI: 10.3389/fmicb.2020.00072] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 01/14/2020] [Indexed: 12/05/2022] Open
Abstract
Burkholderia pseudomallei, the causative agent of melioidosis, can survive and replicate in macrophages. Little is known about B. pseudomallei genes that are induced during macrophage infection. We constructed a B. pseudomallei K96243 promoter trap library with genomic DNA fragments fused to the 5' end of a plasmid-borne gene encoding enhanced green fluorescent protein (eGFP). Microarray analysis showed that the library spanned 88% of the B. pseudomallei genome. The recombinant plasmids were introduced into Burkholderia thailandensis E264, and promoter fusions active during in vitro culture were removed. J774A.1 murine macrophages were infected with the promoter trap library, and J774A.1 cells containing fluorescent bacteria carrying plasmids with active promoters were isolated using flow cytometric-based cell sorting. Candidate macrophage-induced B. pseudomallei genes were identified from the location of the insertions containing an active promoter activity. A proportion of the 138 genes identified in this way have been previously reported to be involved in metabolism and transport, virulence, or adaptation. Novel macrophage-induced B. pseudomallei genes were also identified. Quantitative reverse-transcription PCR analysis of 13 selected genes confirmed gene induction during macrophage infection. Deletion mutants of two macrophage-induced genes from this study were attenuated in Galleria mellonella larvae, suggesting roles in virulence. B. pseudomallei genes activated during macrophage infection may contribute to intracellular life and pathogenesis and merit further investigation toward control strategies for melioidosis.
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Affiliation(s)
- Siroj Jitprasutwit
- Department of Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Niramol Jitprasutwit
- Department of Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | | | - Nattawat Onlamoon
- Siriraj Research Group in Immunobiology and Therapeutic Sciences, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Patoo Withatanung
- Department of Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Veerachat Muangsombut
- Department of Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | | | - Joanne M. Stevens
- The Roslin Institute, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
| | - Catherine Ong
- Defence Medical and Environmental Research Institute, DSO National Laboratories, Singapore, Singapore
| | - Mark P. Stevens
- The Roslin Institute, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
| | | | - Sunee Korbsrisate
- Department of Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
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16
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Metters G, Norville IH, Titball RW, Hemsley CM. From cell culture to cynomolgus macaque: infection models show lineage-specific virulence potential of Coxiella burnetii. J Med Microbiol 2019; 68:1419-1430. [PMID: 31424378 DOI: 10.1099/jmm.0.001064] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Coxiella burnetii is an obligate intracellular pathogen that causes the zoonotic disease Q fever in humans, which can occur in either an acute or a chronic form with serious complications. The bacterium has a wide host range, including unicellular organisms, invertebrates, birds and mammals, with livestock representing the most significant reservoir for human infections. Cell culture models have been used to decipher the intracellular lifestyle of C. burnetii, and several infection models, including invertebrates, rodents and non-human primates, are being used to investigate host-pathogen interactions and to identify bacterial virulence factors and vaccine candidates. However, none of the models replicate all aspects of human disease. Furthermore, it is becoming evident that C. burnetii isolates belonging to different lineages exhibit differences in their virulence in these models. Here, we compare the advantages and disadvantages of commonly used infection models and summarize currently available data for lineage-specific virulence.
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Affiliation(s)
- Georgina Metters
- College of Life and Environmental Sciences - Biosciences, University of Exeter, Exeter, UK
| | - Isobel H Norville
- Defence Science and Technology Laboratory, Porton Down, Salisbury, UK
| | - Richard W Titball
- College of Life and Environmental Sciences - Biosciences, University of Exeter, Exeter, UK
| | - Claudia M Hemsley
- College of Life and Environmental Sciences - Biosciences, University of Exeter, Exeter, UK
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17
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Withatanung P, Kurian D, Tangjittipokin W, Plengvidhya N, Titball RW, Korbsrisate S, Stevens JM. Quantitative Proteomics Reveals Differences in the Response of Neutrophils Isolated from Healthy or Diabetic Subjects to Infection with Capsule-Variant Burkholderia thailandensis. J Proteome Res 2019; 18:2848-2858. [PMID: 31244210 DOI: 10.1021/acs.jproteome.9b00166] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
In Thailand, diabetes mellitus is the most significant risk factor for melioidosis, a severe disease caused by Burkholderia pseudomallei. In this study, neutrophils isolated from healthy or diabetic subjects were infected with B. thailandensis E555, a variant strain with a B. pseudomallei-like capsular polysaccharide used here as a surrogate micro-organism for B. pseudomallei. At 2 h post-infection, neutrophil proteins were subjected to 4-plex iTRAQ-based comparative proteomic analysis. A total of 341 proteins were identified in two or more samples, of which several proteins involved in oxidative stress and inflammation were enriched in infected diabetic neutrophils. We validated this finding by demonstrating that infected diabetic neutrophils generated significantly elevated levels of pro-inflammatory cytokines TNFα, IL-6, IL-1β, and IL-17 compared to healthy neutrophils. Our data also revealed that infected neutrophils from healthy or diabetic individuals undergo apoptotic cell death at distinctly different rates, with infected diabetic neutrophils showing a diminished ability to delay apoptosis and an increased likelihood of undergoing a lytic form of cell death, compared to infected neutrophils from healthy individuals. Increased expression of inflammatory proteins by infected neutrophils could contribute to the increased susceptibility to infection and inflammation in diabetic patients in melioidosis-endemic areas.
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Affiliation(s)
- Patoo Withatanung
- Department of Immunology, Faculty of Medicine Siriraj Hospital , Mahidol University , Bangkok 10700 , Thailand
| | - Dominic Kurian
- The Roslin Institute & Royal (Dick) School of Veterinary Studies , University of Edinburgh, Easter Bush , Midlothian EH25 9RG , United Kingdom
| | - Watip Tangjittipokin
- Department of Immunology, Faculty of Medicine Siriraj Hospital , Mahidol University , Bangkok 10700 , Thailand
| | - Nattachet Plengvidhya
- Department of Medicine, Faculty of Medicine Siriraj Hospital , Mahidol University , Bangkok 10700 , Thailand
| | - Richard W Titball
- Department of Biosciences , University of Exeter , Exeter EX4 4QD , United Kingdom
| | - Sunee Korbsrisate
- Department of Immunology, Faculty of Medicine Siriraj Hospital , Mahidol University , Bangkok 10700 , Thailand
| | - Joanne M Stevens
- The Roslin Institute & Royal (Dick) School of Veterinary Studies , University of Edinburgh, Easter Bush , Midlothian EH25 9RG , United Kingdom
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18
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Savva CG, Clark AR, Naylor CE, Popoff MR, Moss DS, Basak AK, Titball RW, Bokori-Brown M. The pore structure of Clostridium perfringens epsilon toxin. Nat Commun 2019; 10:2641. [PMID: 31201325 PMCID: PMC6572795 DOI: 10.1038/s41467-019-10645-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 05/20/2019] [Indexed: 12/25/2022] Open
Abstract
Epsilon toxin (Etx), a potent pore forming toxin (PFT) produced by Clostridium perfringens, is responsible for the pathogenesis of enterotoxaemia of ruminants and has been suggested to play a role in multiple sclerosis in humans. Etx is a member of the aerolysin family of β-PFTs (aβ-PFTs). While the Etx soluble monomer structure was solved in 2004, Etx pore structure has remained elusive due to the difficulty of isolating the pore complex. Here we show the cryo-electron microscopy structure of Etx pore assembled on the membrane of susceptible cells. The pore structure explains important mutant phenotypes and suggests that the double β-barrel, a common feature of the aβ-PFTs, may be an important structural element in driving efficient pore formation. These insights provide the framework for the development of novel therapeutics to prevent human and animal infections, and are relevant for nano-biotechnology applications. Epsilon toxin (Etx) is a potent pore forming toxin (PFT) produced by Clostridium perfringens. Here authors show the cryo-EM structure of the Etx pore assembled on the membrane of susceptible cells and shed light on pore formation and mutant phenotypes.
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Affiliation(s)
- Christos G Savva
- Leicester Institute of Structural and Chemical Biology, Department of Molecular and Cell Biology, University of Leicester, Lancaster Road, Leicester, LE1 7HB, UK
| | - Alice R Clark
- Faculty of Science and Engineering, University of Wolverhampton, Wulfruna Street, Wolverhampton, WV1 1LY, UK
| | - Claire E Naylor
- Molecular Dimensions, Willie Snaith Road, Newmarket, CB8 7SQ, UK
| | - Michel R Popoff
- Bactéries Anaérobies et Toxines, Institut Pasteur, 25-28 Rue du Docteur Roux, 75724, Paris Cedex 15, France
| | - David S Moss
- Department of Biological Sciences, Birkbeck College, Malet Street, London, WC1E 7HX, UK
| | - Ajit K Basak
- Department of Biological Sciences, Birkbeck College, Malet Street, London, WC1E 7HX, UK
| | - Richard W Titball
- College of Life and Environmental Sciences, University of Exeter, Stocker Road, Exeter, EX4 4QD, UK
| | - Monika Bokori-Brown
- College of Life and Environmental Sciences, University of Exeter, Stocker Road, Exeter, EX4 4QD, UK.
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19
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Hemsley CM, O’Neill PA, Essex-Lopresti A, Norville IH, Atkins TP, Titball RW. Extensive genome analysis of Coxiella burnetii reveals limited evolution within genomic groups. BMC Genomics 2019; 20:441. [PMID: 31164106 PMCID: PMC6549354 DOI: 10.1186/s12864-019-5833-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 05/23/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Coxiella burnetii is a zoonotic pathogen that resides in wild and domesticated animals across the globe and causes a febrile illness, Q fever, in humans. An improved understanding of the genetic diversity of C. burnetii is essential for the development of diagnostics, vaccines and therapeutics, but genotyping data is lacking from many parts of the world. Sporadic outbreaks of Q fever have occurred in the United Kingdom, but the local genetic make-up of C. burnetii has not been studied in detail. RESULTS Here, we report whole genome data for nine C. burnetii sequences obtained in the UK. All four genomes of C. burnetii from cattle, as well as one sheep sample, belonged to Multi-spacer sequence type (MST) 20, whereas the goat samples were MST33 (three genomes) and MST32 (one genome), two genotypes that have not been described to be present in the UK to date. We established the phylogenetic relationship between the UK genomes and 67 publically available genomes based on single nucleotide polymorphisms (SNPs) in the core genome, which confirmed tight clustering of strains within genomic groups, but also indicated that sub-groups exist within those groups. Variation is mainly achieved through SNPs, many of which are non-synonymous, thereby confirming that evolution of C. burnetii is based on modification of existing genes. Finally, we discovered genomic-group specific genome content, which supports a model of clonal expansion of previously established genotypes, with large scale dissemination of some of these genotypes across continents being observed. CONCLUSIONS The genetic make-up of C. burnetii in the UK is similar to the one in neighboring European countries. As a species, C. burnetii has been considered a clonal pathogen with low genetic diversity at the nucleotide level. Here, we present evidence for significant variation at the protein level between isolates of different genomic groups, which mainly affects secreted and membrane-associated proteins. Our results thereby increase our understanding of the global genetic diversity of C. burnetii and provide new insights into the evolution of this emerging zoonotic pathogen.
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Affiliation(s)
- Claudia M. Hemsley
- College of Life and Environmental Sciences – Biosciences, University of Exeter, Exeter, UK
| | - Paul A. O’Neill
- College of Life and Environmental Sciences – Biosciences, University of Exeter, Exeter, UK
| | | | | | - Tim P. Atkins
- College of Life and Environmental Sciences – Biosciences, University of Exeter, Exeter, UK
- Defence Science and Technology Laboratory, Porton Down, Salisbury, UK
| | - Richard W. Titball
- College of Life and Environmental Sciences – Biosciences, University of Exeter, Exeter, UK
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20
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Adler D, Linden JR, Shetty SV, Ma Y, Bokori-Brown M, Titball RW, Vartanian T. Clostridium perfringens Epsilon Toxin Compromises the Blood-Brain Barrier in a Humanized Zebrafish Model. iScience 2019; 15:39-54. [PMID: 31030181 PMCID: PMC6487375 DOI: 10.1016/j.isci.2019.04.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 12/29/2018] [Accepted: 04/08/2019] [Indexed: 12/22/2022] Open
Abstract
Clostridium perfringens epsilon toxin (ETX) is hypothesized to mediate blood-brain barrier (BBB) permeability by binding to the myelin and lymphocyte protein (MAL) on the luminal surface of endothelial cells (ECs). However, the kinetics of this interaction and a general understanding of ETX's behavior in a live organism have yet to be appreciated. Here we investigate ETX binding and BBB breakdown in living Danio rerio (zebrafish). Wild-type zebrafish ECs do not bind ETX. When zebrafish ECs are engineered to express human MAL (hMAL), proETX binding occurs in a time-dependent manner. Injection of activated toxin in hMAL zebrafish initiates BBB leakage, hMAL downregulation, blood vessel stenosis, perivascular edema, and blood stasis. We propose a kinetic model of MAL-dependent ETX binding and neurovascular pathology. By generating a humanized zebrafish BBB model, this study contributes to our understanding of ETX-induced BBB permeability and strengthens the proposal that MAL is the ETX receptor.
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Affiliation(s)
- Drew Adler
- Brain and Mind Research Institute, Weill Cornell Medical College of Cornell University, New York, NY 10065, USA; Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14850, USA
| | - Jennifer R Linden
- Brain and Mind Research Institute, Weill Cornell Medical College of Cornell University, New York, NY 10065, USA
| | - Samantha V Shetty
- Brain and Mind Research Institute, Weill Cornell Medical College of Cornell University, New York, NY 10065, USA
| | - Yinghua Ma
- Brain and Mind Research Institute, Weill Cornell Medical College of Cornell University, New York, NY 10065, USA
| | | | - Richard W Titball
- Department of Biosciences, University of Exeter, Exeter, Devon EX4 4SB, UK
| | - Timothy Vartanian
- Brain and Mind Research Institute, Weill Cornell Medical College of Cornell University, New York, NY 10065, USA.
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21
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Kovacs-Simon A, Hemsley CM, Scott AE, Prior JL, Titball RW. Burkholderia thailandensis strain E555 is a surrogate for the investigation of Burkholderia pseudomallei replication and survival in macrophages. BMC Microbiol 2019; 19:97. [PMID: 31092204 PMCID: PMC6521459 DOI: 10.1186/s12866-019-1469-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 04/30/2019] [Indexed: 02/02/2023] Open
Abstract
Background Burkholderia pseudomallei is a human pathogen causing severe infections in tropical and subtropical regions and is classified as a bio-threat agent. B. thailandensis strain E264 has been proposed as less pathogenic surrogate for understanding the interactions of B. pseudomallei with host cells. Results We show that, unlike B. thailandensis strain E264, the pattern of growth of B. thailandensis strain E555 in macrophages is similar to that of B. pseudomallei. We have genome sequenced B. thailandensis strain E555 and using the annotated sequence identified genes and proteins up-regulated during infection. Changes in gene expression identified more of the known B. pseudomallei virulence factors than changes in protein levels and used together we identified 16% of the currently known B. pseudomallei virulence factors. These findings demonstrate the utility of B. thailandensis strain E555 to study virulence of B. pseudomallei. Conclusions A weakness of studies using B. thailandensis as a surrogate for B. pseudomallei is that the strains used replicate at a slower rate in infected cells. We show that the pattern of growth of B. thailandensis strain E555 in macrophages closely mirrors that of B. pseudomallei. Using this infection model we have shown that virulence factors of B. pseudomallei can be identified as genes or proteins whose expression is elevated on the infection of macrophages. This finding confirms the utility of B. thailandensis strain E555 as a surrogate for B. pseudomallei and this strain should be used for future studies on virulence mechanisms. Electronic supplementary material The online version of this article (10.1186/s12866-019-1469-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- A Kovacs-Simon
- College of Life and Environmental Sciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK.
| | - C M Hemsley
- College of Life and Environmental Sciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK
| | - A E Scott
- CBR Division, Defence Science and Technology Laboratory, Porton Down, Salisbury, SP4 0JQ, UK
| | - J L Prior
- College of Life and Environmental Sciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK.,CBR Division, Defence Science and Technology Laboratory, Porton Down, Salisbury, SP4 0JQ, UK
| | - R W Titball
- College of Life and Environmental Sciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK
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22
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Morici L, Torres AG, Titball RW. Novel multi-component vaccine approaches for Burkholderia pseudomallei. Clin Exp Immunol 2019; 196:178-188. [PMID: 30963550 DOI: 10.1111/cei.13286] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/20/2018] [Indexed: 12/16/2022] Open
Abstract
Burkholderia pseudomallei is the causative agent of melioidosis. Historically believed to be a relatively rare human disease in tropical countries, a recent study estimated that, worldwide, there are approximately 165 000 human melioidosis cases per year, more than half of whom die. The bacterium is inherently resistant to many antibiotics and treatment of the disease is often protracted and ineffective. There is no licensed vaccine against melioidosis, but a vaccine is predicted to be of value if used in high-risk populations. There has been progress over the last decade in the pursuit of an effective vaccine against melioidosis. Animal models of disease including mouse and non-human primates have been developed, and these models show that antibody responses play a key role in protection against melioidosis. Surprisingly, although B. pseudomallei is an intracellular pathogen there is limited evidence that CD8+ T cells play a role in protection. It is evident that a multi-component vaccine, incorporating one or more protective antigens, will probably be essential for protection because of the pathogen's sophisticated virulence mechanisms as well as strain heterogeneity. Multi-component vaccines in development include glycoconjugates, multivalent subunit preparations, outer membrane vesicles and other nano/microparticle platforms and live-attenuated or inactivated bacteria. A consistent finding with vaccine candidates tested in mice is the ability to induce sterilizing immunity at low challenge doses and extended time to death at higher challenge doses. Further research to identify ways of eliciting more potent immune responses might provide a path for licensing an effective vaccine.
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Affiliation(s)
- L Morici
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA, USA
| | - A G Torres
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, USA
| | - R W Titball
- College of Life and Environmental Science, University of Exeter, Exeter, UK
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23
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Bokori-Brown M, Metz J, Petrov PG, Mussai F, De Santo C, Smart NJ, Saunders S, Knight B, Pastan I, Titball RW, Winlove CP. Interactions Between Pseudomonas Immunotoxins and the Plasma Membrane: Implications for CAT-8015 Immunotoxin Therapy. Front Oncol 2018; 8:553. [PMID: 30538953 PMCID: PMC6277520 DOI: 10.3389/fonc.2018.00553] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 11/08/2018] [Indexed: 11/13/2022] Open
Abstract
Acute Lymphoblastic Leukemia (ALL) remains the most frequent cause of cancer-related mortality in children and novel therapies are needed for the treatment of relapsed/refractory childhood ALL. One approach is the targeting of ALL blasts with the Pseudomonas immunotoxin CAT-8015. Although CAT-8015 has potent anti-leukemia activity, with a 32% objective response rate in a phase 1 study of childhood ALL, haemolytic-uremic syndrome (HUS) and vascular leak syndrome (VLS), major dose-limiting toxicities, have limited the use of this therapeutic approach in children. Investigations into the pathogenesis of CAT-8015-induced HUS/VLS are hindered by the lack of an adequate model system that replicates clinical manifestations, but damage to vascular endothelial cells (ECs) and blood cells are believed to be major initiating factors in both syndromes. Since there is little evidence that murine models replicate human HUS/VLS, and CAT-8015-induced HUS/VLS predominantly affects children, we developed human models and used novel methodologies to investigate CAT-8015 interactions with red blood cells (RBCs) from pediatric ALL patients and ECs of excised human mesenteric arteries. We provide evidence that CAT-8015 directly interacts with RBCs, mediated by Pseudomonas toxin. We also show correlation between the electrical properties of the RBC membrane and RBC susceptibility to CAT-8015-induced lysis, which may have clinical implication. Finally, we provide evidence that CAT-8015 is directly cytototoxic to ECs of excised human mesenteric arteries. In conclusion, the human models we developed constitutes the first, and very important, step in understanding the origins of HUS/VLS in immunotoxin therapy and will allow further investigations of HUS/VLS pathogenesis.
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Affiliation(s)
- Monika Bokori-Brown
- College of Life and Environmental Sciences, School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Jeremy Metz
- College of Life and Environmental Sciences, School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Peter G. Petrov
- College of Engineering, Mathematics and Physical Sciences, Department of Physics and Astronomy, University of Exeter, Exeter, United Kingdom
| | - Francis Mussai
- Institute of Immunology and Immunotherapy, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Carmela De Santo
- Institute of Immunology and Immunotherapy, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Neil J. Smart
- Exeter Surgical Health Services Research Unit, Royal Devon and Exeter Hospital, Exeter, United Kingdom
| | - Sarah Saunders
- Histopathology Department, Royal Devon and Exeter Hospital, Exeter, United Kingdom
| | - Bridget Knight
- National Institute for Health Research Exeter Clinical Research Facility, Royal Devon and Exeter National Health Service Foundation Trust, Exeter, United Kingdom
| | - Ira Pastan
- Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, United States
| | - Richard W. Titball
- College of Life and Environmental Sciences, School of Biosciences, University of Exeter, Exeter, United Kingdom
| | - C. Peter Winlove
- College of Engineering, Mathematics and Physical Sciences, Department of Physics and Astronomy, University of Exeter, Exeter, United Kingdom
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24
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Winter AJ, Williams C, Isupov MN, Crocker H, Gromova M, Marsh P, Wilkinson OJ, Dillingham MS, Harmer NJ, Titball RW, Crump MP. The molecular basis of protein toxin HicA-dependent binding of the protein antitoxin HicB to DNA. J Biol Chem 2018; 293:19429-19440. [PMID: 30337369 DOI: 10.1074/jbc.ra118.005173] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 10/16/2018] [Indexed: 12/15/2022] Open
Abstract
Toxin-antitoxin (TA) systems are present in many bacteria and play important roles in bacterial growth, physiology, and pathogenicity. Those that are best studied are the type II TA systems, in which both toxins and antitoxins are proteins. The HicAB system is one of the prototypic TA systems, found in many bacterial species. Complex interactions between the protein toxin (HicA), the protein antitoxin (HicB), and the DNA upstream of the encoding genes regulate the activity of this system, but few structural details are available about how HicA destabilizes the HicB-DNA complex. Here, we determined the X-ray structures of HicB and the HicAB complex to 1.8 and 2.5 Å resolution, respectively, and characterized their DNA interactions. This revealed that HicB forms a tetramer and HicA and HicB form a heterooctameric complex that involves structural reorganization of the C-terminal (DNA-binding) region of HicB. Our observations indicated that HicA has a profound impact on binding of HicB to DNA sequences upstream of hicAB in a stoichiometric-dependent way. At low ratios of HicA:HicB, there was no effect on DNA binding, but at higher ratios, the affinity for DNA declined cooperatively, driving dissociation of the HicA:HicB:DNA complex. These results reveal the structural mechanisms by which HicA de-represses the HicB-DNA complex.
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Affiliation(s)
- Ashley J Winter
- From the School of Chemistry, University of Bristol Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Christopher Williams
- From the School of Chemistry, University of Bristol Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Michail N Isupov
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, United Kingdom
| | - Hannah Crocker
- From the School of Chemistry, University of Bristol Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Mariya Gromova
- From the School of Chemistry, University of Bristol Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Philip Marsh
- From the School of Chemistry, University of Bristol Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Oliver J Wilkinson
- the School of Biochemistry, University of Bristol, Biomedical Sciences Building, University Walk, Bristol BS8 1TD United Kingdom
| | - Mark S Dillingham
- the School of Biochemistry, University of Bristol, Biomedical Sciences Building, University Walk, Bristol BS8 1TD United Kingdom
| | - Nicholas J Harmer
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, United Kingdom
| | - Richard W Titball
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, United Kingdom,
| | - Matthew P Crump
- From the School of Chemistry, University of Bristol Cantock's Close, Bristol BS8 1TS, United Kingdom,
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25
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Smith A, Kaczmar A, Bamford RA, Smith C, Frustaci S, Kovacs-Simon A, O'Neill P, Moore K, Paszkiewicz K, Titball RW, Pagliara S. The Culture Environment Influences Both Gene Regulation and Phenotypic Heterogeneity in Escherichia coli. Front Microbiol 2018; 9:1739. [PMID: 30158905 PMCID: PMC6104134 DOI: 10.3389/fmicb.2018.01739] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Accepted: 07/11/2018] [Indexed: 11/13/2022] Open
Abstract
Microorganisms shape the composition of the medium they are growing in, which in turn has profound consequences on the reprogramming of the population gene-expression profile. In this paper, we investigate the progressive changes in pH and sugar availability in the medium of a growing Escherichia coli (E. coli) culture. We show how these changes have an effect on both the cellular heterogeneity within the microbial community and the gene-expression profile of the microbial population. We measure the changes in gene-expression as E. coli moves from lag, to exponential, and finally into stationary phase. We found that pathways linked to the changes in the medium composition such as ribosomal, tricarboxylic acid cycle (TCA), transport, and metabolism pathways are strongly regulated during the different growth phases. In order to quantify the corresponding temporal changes in the population heterogeneity, we measure the fraction of E. coli persisters surviving different antibiotic treatments during the various phases of growth. We show that the composition of the medium in which β-lactams or quinolones, but not aminoglycosides, are dissolved strongly affects the measured phenotypic heterogeneity within the culture. Our findings contribute to a better understanding on how the composition of the culture medium influences both the reprogramming in the population gene-expression and the emergence of phenotypic variants.
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Affiliation(s)
- Ashley Smith
- Living Systems Institute, University of Exeter, Exeter, United Kingdom.,Biosciences, University of Exeter, Exeter, United Kingdom
| | - Agnieszka Kaczmar
- Living Systems Institute, University of Exeter, Exeter, United Kingdom.,Biosciences, University of Exeter, Exeter, United Kingdom
| | - Rosemary A Bamford
- Living Systems Institute, University of Exeter, Exeter, United Kingdom.,Biosciences, University of Exeter, Exeter, United Kingdom
| | | | - Simona Frustaci
- Living Systems Institute, University of Exeter, Exeter, United Kingdom
| | | | - Paul O'Neill
- Biosciences, University of Exeter, Exeter, United Kingdom
| | - Karen Moore
- Biosciences, University of Exeter, Exeter, United Kingdom
| | | | | | - Stefano Pagliara
- Living Systems Institute, University of Exeter, Exeter, United Kingdom.,Biosciences, University of Exeter, Exeter, United Kingdom
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26
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Allegra E, Titball RW, Carter J, Champion OL. Galleria mellonella larvae allow the discrimination of toxic and non-toxic chemicals. Chemosphere 2018; 198:469-472. [PMID: 29425947 DOI: 10.1016/j.chemosphere.2018.01.175] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 01/22/2018] [Accepted: 01/31/2018] [Indexed: 05/27/2023]
Abstract
The acute toxicities of 19 chemicals were assessed using G. mellonella larvae. The results obtained were compared against LD50 values derived from in vitro cytotoxicity tests and against in vivo acute oral LD50 values. In general, cell culture systems overestimated the toxicity of chemicals, especially low toxicity chemicals. In contrast, toxicity testing in G. mellonella larvae was found to be a reliable predictor for low toxicity chemicals. For the 9 chemicals tested which were assigned to Globally Harmonised System (GHS) category 5, the toxicity measured in G. mellonella larvae was consistent with their GHS categorisation but cytotoxicity measured in 3T3 or NHK cells predicted 4 out of 9 chemicals as having low toxicity. A more robust assessment of the likely toxicity of chemicals in mammals could be made by taking into account their toxicities in both cell cultures and in G. mellonella larvae.
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Burton BR, Tennant RK, Love J, Titball RW, Wraith DC, White HN. Variant proteins stimulate more IgM+ GC B-cells revealing a mechanism of cross-reactive recognition by antibody memory. eLife 2018; 7:26832. [PMID: 29709214 PMCID: PMC5959717 DOI: 10.7554/elife.26832] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 04/20/2018] [Indexed: 12/16/2022] Open
Abstract
Vaccines induce memory B-cells that provide high affinity secondary antibody responses to identical antigens. Memory B-cells can also re-instigate affinity maturation, but how this happens against antigenic variants is poorly understood despite its potential impact on driving broadly protective immunity against pathogens such as Influenza and Dengue. We immunised mice sequentially with identical or variant Dengue-virus envelope proteins and analysed antibody and germinal-centre (GC) responses. Variant protein boosts induced GCs with a higher proportion of IgM+ B cells. The most variant protein re-stimulated GCs with the highest proportion of IgM+ cells with the most diverse, least mutated V-genes and with a slower but efficient serum antibody response. Recombinant antibodies from GC B-cells showed a higher affinity for the variant antigen than antibodies from a primary response, confirming a memory origin. This reveals a new process of antibody memory, that IgM memory cells with fewer mutations participate in secondary responses to variant antigens, demonstrating how the hierarchical structure of B-cell memory is used and indicating the potential and limits of cross-reactive antibody based immunity.
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Affiliation(s)
- Bronwen R Burton
- Faculty of Biomedical Sciences, University of Bristol, Bristol, United Kingdom
| | - Richard K Tennant
- Department of Biosciences, University of Exeter, Exeter, United Kingdom
| | - John Love
- Department of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Richard W Titball
- Department of Biosciences, University of Exeter, Exeter, United Kingdom
| | - David C Wraith
- Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom
| | - Harry N White
- Department of Biosciences, University of Exeter, Exeter, United Kingdom
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Wagley S, Bokori-Brown M, Morcrette H, Malaspina A, D'Arcy C, Gnanapavan S, Lewis N, Popoff MR, Raciborska D, Nicholas R, Turner B, Titball RW. Evidence of Clostridium perfringens epsilon toxin associated with multiple sclerosis. Mult Scler 2018; 25:653-660. [PMID: 29681209 PMCID: PMC6439943 DOI: 10.1177/1352458518767327] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Background: It was recently reported that, using Western blotting, some multiple sclerosis (MS) patients in the United States had antibodies against epsilon toxin (Etx) from Clostridium perfringens, suggesting that the toxin may play a role in the disease. Objective: We investigated for serum antibodies against Etx in UK patients with clinically definite multiple sclerosis (CDMS) or presenting with clinically isolated syndrome (CIS) or optic neuritis (ON) and in age- and gender-matched controls. Methods: We tested sera from CDMS, CIS or ON patients or controls by Western blotting. We also tested CDMS sera for reactivity with linear overlapping peptides spanning the amino acid sequence (Pepscan) of Etx. Results: Using Western blotting, 24% of sera in the combined CDMS, CIS and ON groups (n = 125) reacted with Etx. In the control group (n = 125), 10% of the samples reacted. Using Pepscan, 33% of sera tested reacted with at least one peptide, whereas in the control group only 16% of sera reacted. Out of 61 samples, 21 (43%) were positive to one or other testing methodology. Three samples were positive by Western blotting and Pepscan. Conclusion: Our results broadly support the previous findings and the role of Etx in the aetiology of MS warrants further investigation.
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Affiliation(s)
- Sariqa Wagley
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Monika Bokori-Brown
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Helen Morcrette
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | | | - Caroline D'Arcy
- West London Neuroscience Centre, Charing Cross Hospital, London, UK
| | | | | | - Michel R Popoff
- Bactéries Anaérobies et Toxines, Institut Pasteur, Paris, France
| | | | - Richard Nicholas
- Division of Brain Sciences, Department of Medicine, Imperial College London, London, UK
| | - Ben Turner
- Clinical Research Centre, Barts Health NHS Trust, London, UK
| | - Richard W Titball
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
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29
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Wagley S, Borne R, Harrison J, Baker-Austin C, Ottaviani D, Leoni F, Vuddhakul V, Titball RW. Galleria mellonella as an infection model to investigate virulence of Vibrio parahaemolyticus. Virulence 2018; 9:197-207. [PMID: 28960137 PMCID: PMC5801645 DOI: 10.1080/21505594.2017.1384895] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 09/14/2017] [Accepted: 09/21/2017] [Indexed: 11/24/2022] Open
Abstract
Non-toxigenic V. parahaemolyticus isolates (tdh-/trh-/T3SS2-) have recently been isolated from patients with gastroenteritis. In this study we report that the larvae of the wax moth (Galleria mellonella) are susceptible to infection by toxigenic or non-toxigenic clinical isolates of V. parahaemolyticus. In comparison larvae inoculated with environmental isolates of V. parahaemolyticus did not succumb to disease. Whole genome sequencing of clinical non-toxigenic isolates revealed the presence of a gene encoding a nudix hydrolase, identified as mutT. A V. parahaemolyticus mutT mutant was unable to kill G. mellonella at 24 h post inoculation, indicating a role of this gene in virulence. Our findings show that G. mellonella is a valuable model for investigating screening of possible virulence genes of V. parahaemolyticus and can provide new insights into mechanisms of virulence of atypical non-toxigenic V. parahaemolyticus. These findings will allow improved genetic tests for the identification of pathogenic V. parahaemolyticus to be developed and will have a significant impact for the scientific community.
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Affiliation(s)
- Sariqa Wagley
- Biosciences College of life and Environmental Sciences, University of Exeter, Exeter, Devon, EX4 S4QD, UK
| | | | - Jamie Harrison
- Biosciences College of life and Environmental Sciences, University of Exeter, Exeter, Devon, EX4 S4QD, UK
| | - Craig Baker-Austin
- Centre for Environment, Fisheries, and Aquaculture Science, Weymouth Laboratory, Weymouth, Dorset DT4 8UB UK
| | - Donatella Ottaviani
- Istituto Zooprofilattico Sperimentale dell'Umbria e delle Marche, Laboratorio Nazionale di Riferimento Contaminazioni Batteriologiche dei Molluschi Bivalvi, Ancona, Italy
| | - Francesca Leoni
- Istituto Zooprofilattico Sperimentale dell'Umbria e delle Marche, Laboratorio Nazionale di Riferimento Contaminazioni Batteriologiche dei Molluschi Bivalvi, Ancona, Italy
| | - Varaporn Vuddhakul
- Department of Microbiology, Faculty of Science, Prince of Songkla University, Hat Yai 90110, Thailand
| | - Richard W. Titball
- Biosciences College of life and Environmental Sciences, University of Exeter, Exeter, Devon, EX4 S4QD, UK
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Bamford RA, Smith A, Metz J, Glover G, Titball RW, Pagliara S. Investigating the physiology of viable but non-culturable bacteria by microfluidics and time-lapse microscopy. BMC Biol 2017; 15:121. [PMID: 29262826 PMCID: PMC5738893 DOI: 10.1186/s12915-017-0465-4] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 11/30/2017] [Indexed: 11/29/2022] Open
Abstract
Background Clonal microbial populations often harbor rare phenotypic variants that are typically hidden within the majority of the remaining cells, but are crucial for the population’s resilience to external perturbations. Persister and viable but non-culturable (VBNC) cells are two important clonal bacterial subpopulations that can survive antibiotic treatment. Both persister and VBNC cells pose a serious threat to human health. However, unlike persister cells, which quickly resume growth following drug removal, VBNC cells can remain non-growing for prolonged periods of time, thus eluding detection via traditional microbiological assays. Therefore, understanding the molecular mechanisms underlying the formation of VBNC cells requires the characterization of the clonal population with single-cell resolution. A combination of microfluidics, time-lapse microscopy, and fluorescent reporter strains offers the perfect platform for investigating individual cells while manipulating their environment. Methods Here, we report a novel single-cell approach to investigate VBNC cells. We perform drug treatment, bacterial culturing, and live/dead staining in series by using transcriptional reporter strains and novel adaptations to the mother machine technology. Since we track each cell throughout the experiment, we are able to quantify the size, morphology and fluorescence that each VBNC cell displayed before, during and after drug treatment. Results We show that VBNC cells are not dead or dying cells but share similar phenotypic features with persister cells, suggesting a link between these two subpopulations, at least in the Escherichia coli strain under investigation. We strengthen this link by demonstrating that, before drug treatment, both persister and VBNC cells can be distinguished from the remainder of the population by their lower fluorescence when using a reporter strain for tnaC, encoding the leader peptide of the tnaCAB operon responsible for tryptophan metabolism. Conclusion Our data demonstrates the suitability of our approach for studying the physiology of non-growing cells in response to external perturbations. Our approach will allow the identification of novel biomarkers for the isolation of VBNC and persister cells and will open new opportunities to map the detailed biochemical makeup of these clonal subpopulations. Electronic supplementary material The online version of this article (doi:10.1186/s12915-017-0465-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Rosemary A Bamford
- Biosciences, University of Exeter, Exeter, Devon, EX4 4QD, UK.,Living Systems Institute, University of Exeter, Exeter, Devon, EX4 4QD, UK
| | - Ashley Smith
- Biosciences, University of Exeter, Exeter, Devon, EX4 4QD, UK.,Living Systems Institute, University of Exeter, Exeter, Devon, EX4 4QD, UK
| | - Jeremy Metz
- Biosciences, University of Exeter, Exeter, Devon, EX4 4QD, UK.,Living Systems Institute, University of Exeter, Exeter, Devon, EX4 4QD, UK
| | - Georgina Glover
- Biosciences, University of Exeter, Exeter, Devon, EX4 4QD, UK.,Living Systems Institute, University of Exeter, Exeter, Devon, EX4 4QD, UK
| | | | - Stefano Pagliara
- Biosciences, University of Exeter, Exeter, Devon, EX4 4QD, UK. .,Living Systems Institute, University of Exeter, Exeter, Devon, EX4 4QD, UK.
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31
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Fernandes da Costa SP, Mot D, Geeraerts S, Bokori-Brown M, Van Immerseel F, Titball RW. Variable protection against experimental broiler necrotic enteritis after immunization with the C-terminal fragment of Clostridium perfringens alpha-toxin and a non-toxic NetB variant. Avian Pathol 2017; 45:381-8. [PMID: 26743457 PMCID: PMC5044767 DOI: 10.1080/03079457.2015.1129663] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Necrotic enteritis toxin B (NetB) is a pore-forming toxin produced by Clostridium perfringens and has been shown to play a key role in avian necrotic enteritis, a disease causing significant costs to the poultry production industry worldwide. The aim of this work was to determine whether immunization with a non-toxic variant of NetB (NetB W262A) and the C-terminal fragment of C. perfringens alpha-toxin (CPA247–370) would provide protection against experimental necrotic enteritis. Immunized birds with either antigen or a combination of antigens developed serum antibody levels against NetB and CPA. When CPA247–370 and NetB W262A were used in combination as immunogens, an increased protection was observed after oral challenge by individual dosing, but not after in-feed-challenge.
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Affiliation(s)
| | - Dorien Mot
- b Faculty of Veterinary Medicine, Department of Pathology, Bacteriology and Avian Diseases , Ghent University , Merelbeke , Belgium
| | - Sofie Geeraerts
- b Faculty of Veterinary Medicine, Department of Pathology, Bacteriology and Avian Diseases , Ghent University , Merelbeke , Belgium
| | - Monika Bokori-Brown
- a College of Life and Environmental Sciences , University of Exeter , Exeter , UK
| | - Filip Van Immerseel
- b Faculty of Veterinary Medicine, Department of Pathology, Bacteriology and Avian Diseases , Ghent University , Merelbeke , Belgium
| | - Richard W Titball
- a College of Life and Environmental Sciences , University of Exeter , Exeter , UK
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32
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Titball RW, Burtnick MN, Bancroft GJ, Brett P. Burkholderia pseudomallei and Burkholderia mallei vaccines: Are we close to clinical trials? Vaccine 2017; 35:5981-5989. [DOI: 10.1016/j.vaccine.2017.03.022] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 02/17/2017] [Accepted: 03/07/2017] [Indexed: 10/19/2022]
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33
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Senior NJ, Sasidharan K, Saint RJ, Scott AE, Sarkar-Tyson M, Ireland PM, Bullifent HL, Rong Yang Z, Moore K, Oyston PCF, Atkins TP, Atkins HS, Soyer OS, Titball RW. An integrated computational-experimental approach reveals Yersinia pestis genes essential across a narrow or a broad range of environmental conditions. BMC Microbiol 2017; 17:163. [PMID: 28732479 PMCID: PMC5521123 DOI: 10.1186/s12866-017-1073-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 07/17/2017] [Indexed: 01/07/2023] Open
Abstract
Background The World Health Organization has categorized plague as a re-emerging disease and the potential for Yersinia pestis to also be used as a bioweapon makes the identification of new drug targets against this pathogen a priority. Environmental temperature is a key signal which regulates virulence of the bacterium. The bacterium normally grows outside the human host at 28 °C. Therefore, understanding the mechanisms that the bacterium used to adapt to a mammalian host at 37 °C is central to the development of vaccines or drugs for the prevention or treatment of human disease. Results Using a library of over 1 million Y. pestis CO92 random mutants and transposon-directed insertion site sequencing, we identified 530 essential genes when the bacteria were cultured at 28 °C. When the library of mutants was subsequently cultured at 37 °C we identified 19 genes that were essential at 37 °C but not at 28 °C, including genes which encode proteins that play a role in enabling functioning of the type III secretion and in DNA replication and maintenance. Using genome-scale metabolic network reconstruction we showed that growth conditions profoundly influence the physiology of the bacterium, and by combining computational and experimental approaches we were able to identify 54 genes that are essential under a broad range of conditions. Conclusions Using an integrated computational-experimental approach we identify genes which are required for growth at 37 °C and under a broad range of environments may be the best targets for the development of new interventions to prevent or treat plague in humans. Electronic supplementary material The online version of this article (doi:10.1186/s12866-017-1073-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nicola J Senior
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4SB, UK
| | - Kalesh Sasidharan
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Richard J Saint
- Defence Science Technology Laboratory, Porton Down, Salisbury, SP4 OJQ, UK
| | - Andrew E Scott
- Defence Science Technology Laboratory, Porton Down, Salisbury, SP4 OJQ, UK
| | - Mitali Sarkar-Tyson
- Defence Science Technology Laboratory, Porton Down, Salisbury, SP4 OJQ, UK.,Marshall Centre for Infectious Disease Research and Training, School of Pathology and Laboratory Medicine, University of Western Australia, Perth, WA, 6009, Australia
| | - Philip M Ireland
- Defence Science Technology Laboratory, Porton Down, Salisbury, SP4 OJQ, UK
| | - Helen L Bullifent
- Defence Science Technology Laboratory, Porton Down, Salisbury, SP4 OJQ, UK
| | - Z Rong Yang
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4SB, UK
| | - Karen Moore
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4SB, UK
| | - Petra C F Oyston
- Defence Science Technology Laboratory, Porton Down, Salisbury, SP4 OJQ, UK
| | - Timothy P Atkins
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4SB, UK.,Defence Science Technology Laboratory, Porton Down, Salisbury, SP4 OJQ, UK
| | - Helen S Atkins
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4SB, UK.,Defence Science Technology Laboratory, Porton Down, Salisbury, SP4 OJQ, UK
| | - Orkun S Soyer
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Richard W Titball
- College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4SB, UK.
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34
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Vanaporn M, Sarkar-Tyson M, Kovacs-Simon A, Ireland PM, Pumirat P, Korbsrisate S, Titball RW, Butt A. Trehalase plays a role in macrophage colonization and virulence of Burkholderia pseudomallei in insect and mammalian hosts. Virulence 2017; 8:30-40. [PMID: 27367830 PMCID: PMC5963195 DOI: 10.1080/21505594.2016.1199316] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 06/01/2016] [Accepted: 06/03/2016] [Indexed: 10/21/2022] Open
Abstract
Trehalose is a disaccharide formed from two glucose molecules. This sugar molecule can be isolated from a range of organisms including bacteria, fungi, plants and invertebrates. Trehalose has a variety of functions including a role as an energy storage molecule, a structural component of glycolipids and plays a role in the virulence of some microorganisms. There are many metabolic pathways that control the biosynthesis and degradation of trehalose in different organisms. The enzyme trehalase forms part of a pathway that converts trehalose into glucose. In this study we set out to investigate whether trehalase plays a role in both stress adaptation and virulence of Burkholderia pseudomallei. We show that a trehalase deletion mutant (treA) had increased tolerance to thermal stress and produced less biofilm than the wild type B. pseudomallei K96243 strain. We also show that the ΔtreA mutant has reduced ability to survive in macrophages and that it is attenuated in both Galleria mellonella (wax moth larvae) and a mouse infection model. This is the first report that trehalase is important for bacterial virulence.
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Affiliation(s)
- Muthita Vanaporn
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | | | - Andrea Kovacs-Simon
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Philip M. Ireland
- CBR Division, Defense Science and Technology Laboratory, Salisbury, UK
| | - Pornpan Pumirat
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Sunee Korbsrisate
- Department of Immunology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Richard W. Titball
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Aaron Butt
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
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35
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Anutrakunchai C, Hemsley H, Sermswan RW, Titball RW, Chareonsudjai S, Taweechaisupapong S. Role of RelA and SpoT in Burkholderia pseudomallei survival, biofilm formation and ceftazidime tolerance during nutritional stress. Trop Biomed 2016; 33:786-798. [PMID: 33579076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Burkholderia pseudomallei a saprophyte found in soil and stagnant water is the causative agent of human melioidosis, an often cause fatal disease. B. pseudomallei is intrinsically resistant to many antibiotics. The stringent response is a global bacterial adaptation process in response to nutritional limitation and is mediated by the alarmone (p)ppGpp, which is produced by two proteins, RelA and SpoT. In order to test whether the stringent response is involved in ceftazidime tolerance, biofilm formation, and bacterial survival in the soil microcosm, B. pseudomallei strain K96243 and its isogenic ΔrelA and ΔrelAΔspoT mutants were grown in rich and nutrient-limited media. In nutrient-limiting conditions, both the wild type and mutants were found to be up to 64-times more tolerant to ceftazidime than when grown in rich culture conditions. Moreover, the biofilm formation of all bacterial isolates tested were significantly higher under nutrient-limiting conditions than under nutrient-rich conditions. The ΔrelAΔspoT mutant produced less biofilm than its wild type or ΔrelA mutant under nutrient-limiting conditions. The survival of the ΔrelAΔspoT double mutant cultured in 1% moisture content soil was significantly decreased compared to the wild type and the ΔrelA mutant. Therefore, the RelA/SpoT protein family might represent a promising target for the development of novel antimicrobial agents to combat B. pseudomallei.
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Affiliation(s)
- C Anutrakunchai
- Biofilm research group, Faculty of Dentistry, Khon Kaen University, Khon Kaen 40002, Thailand
- Melioidosis research center, Khon Kaen University, Khon Kaen 40002, Thailand
- Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
| | - H Hemsley
- College of Life and Environmental Sciences, Biosciences; University of Exeter, Stocker Road, Exeter, EX4 4QD Devon, United Kingdom
| | - R W Sermswan
- Melioidosis research center, Khon Kaen University, Khon Kaen 40002, Thailand
- Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
| | - R W Titball
- College of Life and Environmental Sciences, Biosciences; University of Exeter, Stocker Road, Exeter, EX4 4QD Devon, United Kingdom
| | - S Chareonsudjai
- Biofilm research group, Faculty of Dentistry, Khon Kaen University, Khon Kaen 40002, Thailand
- Melioidosis research center, Khon Kaen University, Khon Kaen 40002, Thailand
- Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
| | - S Taweechaisupapong
- Biofilm research group, Faculty of Dentistry, Khon Kaen University, Khon Kaen 40002, Thailand
- Melioidosis research center, Khon Kaen University, Khon Kaen 40002, Thailand
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36
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Cizmeci D, Dempster EL, Champion OL, Wagley S, Akman OE, Prior JL, Soyer OS, Mill J, Titball RW. Mapping epigenetic changes to the host cell genome induced by Burkholderia pseudomallei reveals pathogen-specific and pathogen-generic signatures of infection. Sci Rep 2016; 6:30861. [PMID: 27484700 PMCID: PMC4971488 DOI: 10.1038/srep30861] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 07/07/2016] [Indexed: 01/26/2023] Open
Abstract
The potential for epigenetic changes in host cells following microbial infection has been widely suggested, but few examples have been reported. We assessed genome-wide patterns of DNA methylation in human macrophage-like U937 cells following infection with Burkholderia pseudomallei, an intracellular bacterial pathogen and the causative agent of human melioidosis. Our analyses revealed significant changes in host cell DNA methylation, at multiple CpG sites in the host cell genome, following infection. Infection induced differentially methylated probes (iDMPs) showing the greatest changes in DNA methylation were found to be in the vicinity of genes involved in inflammatory responses, intracellular signalling, apoptosis and pathogen-induced signalling. A comparison of our data with reported methylome changes in cells infected with M. tuberculosis revealed commonality of differentially methylated genes, including genes involved in T cell responses (BCL11B, FOXO1, KIF13B, PAWR, SOX4, SYK), actin cytoskeleton organisation (ACTR3, CDC42BPA, DTNBP1, FERMT2, PRKCZ, RAC1), and cytokine production (FOXP1, IRF8, MR1). Overall our findings show that pathogenic-specific and pathogen-common changes in the methylome occur following infection.
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Affiliation(s)
- Deniz Cizmeci
- College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, United Kingdom
| | - Emma L Dempster
- University of Exeter Medical School, Exeter University, Exeter, United Kingdom
| | - Olivia L Champion
- College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Sariqa Wagley
- College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Ozgur E Akman
- College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, United Kingdom
| | - Joann L Prior
- College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Orkun S Soyer
- School of Life Sciences, University of Warwick, United Kingdom
| | - Jonathan Mill
- University of Exeter Medical School, Exeter University, Exeter, United Kingdom.,Institute of Psychiatry, Psychology &Neuroscience, King's College London, United Kingdom
| | - Richard W Titball
- College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
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Abstract
We have developed a method to analyze the functionality of putative TA loci by expressing them in Escherichia coli. Here, we describe the procedure for cloning recombinant TA genes into inducible plasmids and expressing these in E. coli. Following expression, toxicity, resuscitation of growth, and changes in persister cell formation are assayed. This can confirm whether predicted TA loci are active in E. coli and whether expression can affect persister cell formation.
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Affiliation(s)
- Aaron T Butt
- Department of Infection and Immunity, Medical School, University of Sheffield, Beech Hill Road, Sheffield, S10 2RX, UK
| | - Richard W Titball
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK.
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38
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Abstract
The epithelial Madin Darby canine kidney (MDCK) cell line, Caucasian renal leiomyoblastoma (G-402) cells, human small airways epithelial (HSAE) cells, human bronchial epithelial (HBE) cells and human renal proximal tubule (HRPT) epithelial cells were examined for sensitivity to Clostridium perfringens biotype D o-toxin. MDCK and G-402 cells were confirmed as being the only established cell lines that are sensitive to the toxin. HSAE, HBE and HRPT epithelial cells were only found to be sensitive to the toxin at concentrations of -1 mg/ mL. Cultures of MDCK and G-402 cells, with increased resistance (tolerance) to the cytotoxic effects of o-toxin, were developed by exposing these cultures to progressively higher concentrations of toxin. The greatest relative increase in tolerance to o-toxin was developed in MDCK cells, in which the LC50 in control cultures was 2mg/mL as determined by the MTS/PMS assay system; after selection for tolerance, this was raised to 100 mg/mL. This represents a 50-fold increase in tolerance as measured by this index. Using G-402 cells, it was possible to increase the LC50 by twofold from 290 to 590 mg/mL. Subsequent 2-D electrophoresis of membrane preparations from tolerant and control MDCK cells revealed that the expression of a discrete group of proteins found in control cells with a range of molecular weights from 32–36 kDa, all with acidic isoelectric points (IEPs), were either not expressed in o-toxin tolerant cells or had undergone a shift in IEP to a more alkaline pH in tolerant cells. This suggests that o-toxin lethality in MDCK cells may be mediated by membrane-located proteins. Their absence or alteration in toxin-resistant cells would, at least partly, explain the failure of most cell lines to demonstrate sensitivity to this toxin, despite being derived from tissues that are damaged by o-toxin. This approach may have utility in the study of other toxin / cell interactions and could be used in the development of novel medical countermeasures by identifying cellular targets which mediate toxin lethality.
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Affiliation(s)
- Dominic R Beal
- Biomedical Sciences Department, Dstl, Porton Down, Salisbury, Wiltshire SP4 0JQ, UK
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39
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Abstract
Mammals are widely used by microbiologists as a model host species to study infectious diseases of humans and domesticated livestock. These studies have been pivotal for our understanding of mechanisms of virulence and have allowed the development of diagnostics, pre-treatments and therapies for disease. However, over the past decade we have seen efforts to identify organisms which can be used as alternatives to mammals for these studies. The drivers for this are complex and multifactorial and include cost, ethical and scientific considerations. Galleria mellonella have been used as an alternative infection model since the 1980s and its utility for the study of bacterial disease and antimicrobial discovery was recently comprehensively reviewed. The wider applications of G. mellonella as a model host, including its susceptibility to 29 species of fungi, 7 viruses, 1 species of parasite and 16 biological toxins, are described in this perspective. In addition, the latest developments in the standardisation of G. mellonella larvae for research purposes has been reviewed.
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Affiliation(s)
- Olivia L Champion
- a University of Exeter, College of Life and Environmental Science , Exeter , Devon , UK
| | - Sariqa Wagley
- a University of Exeter, College of Life and Environmental Science , Exeter , Devon , UK
| | - Richard W Titball
- a University of Exeter, College of Life and Environmental Science , Exeter , Devon , UK
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40
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Scott AE, Christ WJ, George AJ, Stokes MGM, Lohman GJS, Guo Y, Jones M, Titball RW, Atkins TP, Campbell AS, Prior JL. Protection against Experimental Melioidosis with a Synthetic manno-Heptopyranose Hexasaccharide Glycoconjugate. Bioconjug Chem 2016; 27:1435-46. [PMID: 27124182 PMCID: PMC4911622 DOI: 10.1021/acs.bioconjchem.5b00525] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
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Melioidosis is an emerging infectious
disease caused by Burkholderia pseudomallei and is associated with
high morbidity and mortality rates in endemic areas. Antibiotic treatment
is protracted and not always successful; even with appropriate therapy,
up to 40% of individuals presenting with melioidosis in Thailand succumb
to infection. In these circumstances, an effective vaccine has the
potential to have a dramatic impact on both the scale and the severity
of disease. Currently, no vaccines are licensed for human use. A leading
vaccine candidate is the capsular polysaccharide consisting of a homopolymer
of unbranched 1→3 linked 2-O-acetyl-6-deoxy-β-d-manno-heptopyranose. Here, we present the
chemical synthesis of this challenging antigen using a novel modular
disaccharide assembly approach. The resulting hexasaccharide was coupled
to the nontoxic Hc domain of tetanus toxin as a carrier
protein to promote recruitment of T-cell help and provide a scaffold
for antigen display. Mice immunized with the glycoconjugate developed
IgM and IgG responses capable of recognizing native capsule, and were
protected against infection with over 120 × LD50 of B. pseudomallei strain K96243. This is the first
report of the chemical synthesis of an immunologically relevant and
protective hexasaccharide fragment of the capsular polysaccharide
of B. pseudomallei and serves as the
rational starting point for the development of an effective licensed
vaccine for this emerging infectious disease.
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Affiliation(s)
- Andrew E Scott
- Defence Science and Technology Laboratory , Porton Down, Salisbury, Wiltshire SP4 0JQ, United Kingdom
| | - William J Christ
- Corden Pharma International Inc. (formerly Ancora Pharmaceuticals Inc.) , Woburn, Massachusetts 01801 United States
| | - Alison J George
- Defence Science and Technology Laboratory , Porton Down, Salisbury, Wiltshire SP4 0JQ, United Kingdom
| | - Margaret G M Stokes
- Defence Science and Technology Laboratory , Porton Down, Salisbury, Wiltshire SP4 0JQ, United Kingdom
| | - Gregory J S Lohman
- Corden Pharma International Inc. (formerly Ancora Pharmaceuticals Inc.) , Woburn, Massachusetts 01801 United States
| | - Yuhong Guo
- Corden Pharma International Inc. (formerly Ancora Pharmaceuticals Inc.) , Woburn, Massachusetts 01801 United States
| | - Matthew Jones
- Corden Pharma International Inc. (formerly Ancora Pharmaceuticals Inc.) , Woburn, Massachusetts 01801 United States
| | - Richard W Titball
- College of Life and Environmental Sciences, University of Exeter , Exeter, Devon EX4 4QD, United Kingdom
| | - Timothy P Atkins
- Defence Science and Technology Laboratory , Porton Down, Salisbury, Wiltshire SP4 0JQ, United Kingdom
| | - A Stewart Campbell
- Corden Pharma International Inc. (formerly Ancora Pharmaceuticals Inc.) , Woburn, Massachusetts 01801 United States
| | - Joann L Prior
- Defence Science and Technology Laboratory , Porton Down, Salisbury, Wiltshire SP4 0JQ, United Kingdom
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41
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Bokori-Brown M, Martin TG, Naylor CE, Basak AK, Titball RW, Savva CG. Cryo-EM structure of lysenin pore elucidates membrane insertion by an aerolysin family protein. Nat Commun 2016; 7:11293. [PMID: 27048994 PMCID: PMC4823867 DOI: 10.1038/ncomms11293] [Citation(s) in RCA: 103] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 03/09/2016] [Indexed: 12/12/2022] Open
Abstract
Lysenin from the coelomic fluid of the earthworm Eisenia fetida belongs to the aerolysin family of small β-pore-forming toxins (β-PFTs), some members of which are pathogenic to humans and animals. Despite efforts, a high-resolution structure of a channel for this family of proteins has been elusive and therefore the mechanism of activation and membrane insertion remains unclear. Here we determine the pore structure of lysenin by single particle cryo-EM, to 3.1 Å resolution. The nonameric assembly reveals a long β-barrel channel spanning the length of the complex that, unexpectedly, includes the two pre-insertion strands flanking the hypothetical membrane-insertion loop. Examination of other members of the aerolysin family reveals high structural preservation in this region, indicating that the membrane-insertion pathway in this family is conserved. For some toxins, proteolytic activation and pro-peptide removal will facilitate unfolding of the pre-insertion strands, allowing them to form the β-barrel of the channel. Lysenin is member of the aerolysin family of small ß-barrel pore-forming toxins that include virulence factors from several human and animal pathogens. Here the authors determine the structure of the lysenin pore by single particle cryo- EM and propose a conserved pore formation mechanism for the aerolysin protein family.
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Affiliation(s)
- Monika Bokori-Brown
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Thomas G Martin
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK
| | - Claire E Naylor
- Department of Biological Sciences, Birkbeck College, Malet Street, London WC1E 7HX, UK
| | - Ajit K Basak
- Department of Biological Sciences, Birkbeck College, Malet Street, London WC1E 7HX, UK
| | - Richard W Titball
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Christos G Savva
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK
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42
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Bokori-Brown M, Petrov PG, Khafaji MA, Mughal MK, Naylor CE, Shore AC, Gooding KM, Casanova F, Mitchell TJ, Titball RW, Winlove CP. Red Blood Cell Susceptibility to Pneumolysin: CORRELATION WITH MEMBRANE BIOCHEMICAL AND PHYSICAL PROPERTIES. J Biol Chem 2016; 291:10210-27. [PMID: 26984406 DOI: 10.1074/jbc.m115.691899] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Indexed: 12/20/2022] Open
Abstract
This study investigated the effect of the biochemical and biophysical properties of the plasma membrane as well as membrane morphology on the susceptibility of human red blood cells to the cholesterol-dependent cytolysin pneumolysin, a key virulence factor of Streptococcus pneumoniae, using single cell studies. We show a correlation between the physical properties of the membrane (bending rigidity and surface and dipole electrostatic potentials) and the susceptibility of red blood cells to pneumolysin-induced hemolysis. We demonstrate that biochemical modifications of the membrane induced by oxidative stress, lipid scrambling, and artificial cell aging modulate the cell response to the toxin. We provide evidence that the diversity of response to pneumolysin in diabetic red blood cells correlates with levels of glycated hemoglobin and that the mechanical properties of the red blood cell plasma membrane are altered in diabetes. Finally, we show that diabetic red blood cells are more resistant to pneumolysin and the related toxin perfringolysin O relative to healthy red blood cells. Taken together, these studies indicate that the diversity of cell response to pneumolysin within a population of human red blood cells is influenced by the biophysical and biochemical status of the plasma membrane and the chemical and/or oxidative stress pre-history of the cell.
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Affiliation(s)
- Monika Bokori-Brown
- From the College of Life and Environmental Sciences, School of Biosciences, University of Exeter, Exeter EX4 4QD, United Kingdom,
| | - Peter G Petrov
- the College of Engineering, Mathematics and Physical Sciences, School of Physics, University of Exeter, Exeter EX4 4QL, United Kingdom
| | - Mawya A Khafaji
- the College of Engineering, Mathematics and Physical Sciences, School of Physics, University of Exeter, Exeter EX4 4QL, United Kingdom
| | - Muhammad K Mughal
- the Institute of Microbiology and Infection, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Claire E Naylor
- the Department of Biological Sciences, Birkbeck College, Malet Street, London WC1E 7HX, United Kingdom
| | - Angela C Shore
- the Department of Diabetes and Vascular Medicine, University of Exeter Medical School, Barrack Road, Exeter EX2 5AX, United Kingdom, the National Institute for Health Research Exeter Clinical Research Facility, Royal Devon and Exeter National Health Service Foundation Trust, Exeter EX2 5DW, United Kingdom, and
| | - Kim M Gooding
- the Department of Diabetes and Vascular Medicine, University of Exeter Medical School, Barrack Road, Exeter EX2 5AX, United Kingdom, the National Institute for Health Research Exeter Clinical Research Facility, Royal Devon and Exeter National Health Service Foundation Trust, Exeter EX2 5DW, United Kingdom, and
| | - Francesco Casanova
- the Department of Diabetes and Vascular Medicine, University of Exeter Medical School, Barrack Road, Exeter EX2 5AX, United Kingdom, the National Institute for Health Research Exeter Clinical Research Facility, Royal Devon and Exeter National Health Service Foundation Trust, Exeter EX2 5DW, United Kingdom, and
| | - Tim J Mitchell
- the Institute of Microbiology and Infection, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Richard W Titball
- From the College of Life and Environmental Sciences, School of Biosciences, University of Exeter, Exeter EX4 4QD, United Kingdom
| | - C Peter Winlove
- the College of Engineering, Mathematics and Physical Sciences, School of Physics, University of Exeter, Exeter EX4 4QL, United Kingdom
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43
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Champion OL, Gourlay LJ, Scott AE, Lassaux P, Conejero L, Perletti L, Hemsley C, Prior J, Bancroft G, Bolognesi M, Titball RW. Immunisation with proteins expressed during chronic murine melioidosis provides enhanced protection against disease. Vaccine 2016; 34:1665-71. [PMID: 26917010 DOI: 10.1016/j.vaccine.2016.02.038] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 01/29/2016] [Accepted: 02/15/2016] [Indexed: 11/20/2022]
Abstract
There is an urgent need for an effective vaccine against human disease caused by Burkholderia pseudomallei, and although a wide range of candidates have been tested in mice none provide high level protection. We considered this might reflect the inability of these vaccine candidates to protect against chronic disease. Using Q-RT PCR we have identified 6 genes which are expressed in bacteria colonising spleens and lungs of chronically infected mice. Three of the genes (BPSL1897, BPSL3369 and BPSL2287) have been expressed in Escherichia coli and the encoded proteins purified. We have also included BPSL2765, a protein known to induce immune responses associated with a reduced incidence of chronic/recurrent disease in humans. Immunisation of mice with a combination of these antigens resulted in the induction of antibody responses against all of the proteins. Compared with mice immunised with capsular polysaccharide or LolC protein, mice immunised with the combination of chronic stage antigens showed enhanced protection against experimental disease in mice.
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Affiliation(s)
- Olivia L Champion
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Louise J Gourlay
- Department of Biosciences, University of Milan, Milan 20133, Italy
| | - Andrew E Scott
- Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire, UK
| | - Patricia Lassaux
- Department of Biosciences, University of Milan, Milan 20133, Italy
| | - Laura Conejero
- London School of Hygiene and Tropical Medicine, Keppler Street, London WC1E 7HT, UK
| | - Lucia Perletti
- Department of Biosciences, University of Milan, Milan 20133, Italy
| | - Claudia Hemsley
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Joann Prior
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK; Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire, UK
| | - Gregory Bancroft
- London School of Hygiene and Tropical Medicine, Keppler Street, London WC1E 7HT, UK
| | - Martino Bolognesi
- Department of Biosciences, University of Milan, Milan 20133, Italy; Consiglio Nazionale delle Ricerche, Institute of Biophysics, University of Milan, Milan 20133, Italy
| | - Richard W Titball
- College of Life and Environmental Sciences, University of Exeter, Exeter, UK.
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44
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Butt A, Halliday N, Williams P, Atkins HS, Bancroft GJ, Titball RW. Burkholderia pseudomallei kynB plays a role in AQ production, biofilm formation, bacterial swarming and persistence. Res Microbiol 2015; 167:159-67. [PMID: 26654915 DOI: 10.1016/j.resmic.2015.11.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 11/17/2015] [Accepted: 11/18/2015] [Indexed: 02/07/2023]
Abstract
Kynurenine formamidase (KynB) forms part of the kynurenine pathway which metabolises tryptophan to anthranilate. This metabolite can be used for downstream production of 2-alkyl-4-quinolone (AQ) signalling molecules that control virulence in Pseudomonas aeruginosa. Here we investigate the role of kynB in the production of AQs and virulence-associated phenotypes of Burkholderia pseudomallei K96243, the causative agent of melioidosis. Deletion of kynB resulted in reduced AQ production, increased biofilm formation, decreased swarming and increased tolerance to ciprofloxacin. Addition of exogenous anthranilic acid restored the biofilm phenotype, but not the persister phenotype. This study suggests the kynurenine pathway is a critical source of anthranilate and signalling molecules that may regulate B. pseudomallei virulence.
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Affiliation(s)
- Aaron Butt
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK.
| | - Nigel Halliday
- Centre for Biomolecular Sciences, School of Biosciences, University of Nottingham, Nottingham, UK.
| | - Paul Williams
- Centre for Biomolecular Sciences, School of Biosciences, University of Nottingham, Nottingham, UK.
| | - Helen S Atkins
- Defence Science and Technology Laboratory, Porton Down, Salisbury, UK.
| | - Gregory J Bancroft
- Department of Immunology and Infection, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK.
| | - Richard W Titball
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK.
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45
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Jewell SA, Titball RW, Huyet J, Naylor CE, Basak AK, Gologan P, Winlove CP, Petrov PG. Clostridium perfringensα-toxin interaction with red cells and model membranes. Soft Matter 2015; 11:7748-7761. [PMID: 26303814 DOI: 10.1039/c5sm00876j] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The effects of Clostridium perfringensα-toxin on host cells have previously been studied extensively but the biophysical processes associated with toxicity are poorly understood. The work reported here shows that the initial interaction between the toxin and lipid membrane leads to measurable changes in the physical properties and morphology of the membrane. A Langmuir monolayer technique was used to assess the response of different lipid species to toxin. Sphingomyelin and unsaturated phosphatidylcholine showed the highest susceptibility to toxin lypolitic action, with a two stage response to the toxin (an initial, rapid hydrolysis stage followed by the insertion and/or reorganisation of material in the monolayer). Fluorescence confocal microscopy on unsaturated phosphatidylcholine vesicles shows that the toxin initially aggregates at discrete sites followed by the formation of localised "droplets" accumulating the hydrolysis products. This process is accompanied by local increases in the membrane dipole potential by about 50 (±42) mV. In contrast, red blood cells incubated with the toxin suffered a decrease of the membrane dipole potential by 50 (±40) mV in areas of high toxin activity (equivalent to a change in electric field strength of 10(7) V m(-1)) which is sufficient to affect the functioning of the cell membrane. Changes in erythrocyte morphology caused by the toxin are presented, and the early stages of interaction between toxin and membrane are characterised using thermal shape fluctuation analysis of red cells which revealed two distinct regimes of membrane-toxin interaction.
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Affiliation(s)
- S A Jewell
- School of Physics, University of Exeter, Stocker Road, Exeter, EX4 4QL, UK.
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46
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Benthall G, Touzel RE, Hind CK, Titball RW, Sutton JM, Thomas RJ, Wand ME. Evaluation of antibiotic efficacy against infections caused by planktonic or biofilm cultures of Pseudomonas aeruginosa and Klebsiella pneumoniae in Galleria mellonella. Int J Antimicrob Agents 2015; 46:538-45. [PMID: 26364845 DOI: 10.1016/j.ijantimicag.2015.07.014] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 05/19/2015] [Accepted: 07/08/2015] [Indexed: 10/23/2022]
Abstract
The lack of novel antibiotics for more than a decade has placed increased pressure on existing therapies to combat the emergence of multidrug-resistant (MDR) bacterial pathogens. This study evaluated the Galleria mellonella insect model in determining the efficacy of available antibiotics against planktonic and biofilm infections of MDR Pseudomonas aeruginosa and Klebsiella pneumoniae strains in comparison with in vitro minimum inhibitory concentration (MIC) determination. In general, in vitro analysis agreed with the G. mellonella studies, and susceptibility in Galleria identified different drug resistance mechanisms. However, the carbapenems tested appeared to perform better in vivo than in vitro, with meropenem and imipenem able to clear K. pneumoniae and P. aeruginosa infections with strains that had bla(NDM-1) and bla(VIM) carbapenemases. This study also established an implant model in G. mellonella to allow testing of antibiotic efficacy against biofilm-derived infections. A reduction in antibiotic efficacy of amikacin against K. pneumoniae and P. aeruginosa biofilms was observed compared with a planktonic infection. Ciprofloxacin was found to be less effective at clearing a P. aeruginosa biofilm infection compared with a planktonic infection, but no statistical difference was seen between K. pneumoniae biofilm and planktonic infections treated with this antibiotic (P>0.05). This study provides important information regarding the suitability of Galleria as a model for antibiotic efficacy testing both against planktonic and biofilm-derived MDR infections.
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Affiliation(s)
- Gabriel Benthall
- Public Health England, Microbiology Services Division, Porton Down, Salisbury, Wiltshire SP4 0JG, UK; College of Life and Environmental Sciences, University of Exeter, Exeter, Devon EX4 4QD, UK
| | - Rebecca E Touzel
- Public Health England, Microbiology Services Division, Porton Down, Salisbury, Wiltshire SP4 0JG, UK
| | - Charlotte K Hind
- Public Health England, Microbiology Services Division, Porton Down, Salisbury, Wiltshire SP4 0JG, UK
| | - Richard W Titball
- College of Life and Environmental Sciences, University of Exeter, Exeter, Devon EX4 4QD, UK
| | - J Mark Sutton
- Public Health England, Microbiology Services Division, Porton Down, Salisbury, Wiltshire SP4 0JG, UK
| | - Rachael J Thomas
- College of Life and Environmental Sciences, University of Exeter, Exeter, Devon EX4 4QD, UK
| | - Matthew E Wand
- Public Health England, Microbiology Services Division, Porton Down, Salisbury, Wiltshire SP4 0JG, UK.
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47
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Harrison JW, Dung TTN, Siddiqui F, Korbrisate S, Bukhari H, Tra MPV, Hoang NVM, Carrique-Mas J, Bryant J, Campbell JI, Studholme DJ, Wren BW, Baker S, Titball RW, Champion OL. Identification of possible virulence marker from Campylobacter jejuni isolates. Emerg Infect Dis 2015; 20:1026-9. [PMID: 24856088 PMCID: PMC4036754 DOI: 10.3201/eid2006.130635] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
A novel protein translocation system, the type-6 secretion system (T6SS), may play a role in virulence of Campylobacter jejuni. We investigated 181 C. jejuni isolates from humans, chickens, and environmental sources in Vietnam, Thailand, Pakistan, and the United Kingdom for T6SS. The marker was most prevalent in human and chicken isolates from Vietnam.
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48
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Rinchai D, Riyapa D, Buddhisa S, Utispan K, Titball RW, Stevens MP, Stevens JM, Ogawa M, Tanida I, Koike M, Uchiyama Y, Ato M, Lertmemongkolchai G. Macroautophagy is essential for killing of intracellular Burkholderia pseudomallei in human neutrophils. Autophagy 2015; 11:748-55. [PMID: 25996656 PMCID: PMC4509438 DOI: 10.1080/15548627.2015.1040969] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Revised: 04/08/2015] [Accepted: 04/09/2015] [Indexed: 12/23/2022] Open
Abstract
Neutrophils play a key role in the control of Burkholderia pseudomallei, the pathogen that causes melioidosis. Here, we show that survival of intracellular B. pseudomallei was significantly increased in the presence of 3-methyladenine or lysosomal cathepsin inhibitors. The LC3-flux was increased in B. pseudomallei-infected neutrophils. Concordant with this result, confocal microscopy analyses using anti-LC3 antibodies revealed that B. pseudomallei-containing phagosomes partially overlapped with LC3-positive signal at 3 and 6 h postinfection. Electron microscopic analyses of B. pseudomallei-infected neutrophils at 3 h revealed B. pseudomallei-containing phagosomes that occasionally fused with phagophores or autophagosomes. Following infection with a B. pseudomallei mutant lacking the Burkholderia secretion apparatus Bsa Type III secretion system, neither this characteristic structure nor bacterial escape into the cytosol were observed. These findings indicate that human neutrophils are able to recruit autophagic machinery adjacent to B. pseudomallei-containing phagosomes in a Type III secretion system-dependent manner.
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Key Words
- 3MA, methyladenine
- Bp, Burkholderia pseudomallei
- Bsa, Burkholderia secretion apparatus
- Burkholderia pseudomallei
- KM, kanamycin
- LAMP1, lysosomal-associated membrane protein 1
- LC3-I, unlipidated form of LC3
- LC3-II
- LC3-II, LC3-phospholipid conjugated and phagophore or autophagosome-associated form of LC3
- MAP1LC3/LC3, microtubule-associated protein 1 light chain 3
- MOI, multiplicity of infection
- NET, Neutrophil Extracellular Taps
- T3SS
- T3SS, Type III secretion system
- WT, wild type
- autophagy
- melioidosis
- neutrophils
- p.i., postinfection
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Affiliation(s)
- Darawan Rinchai
- The Cellular and Molecular Immunology Unit, the Center for Research and Development of Medical Diagnostic Laboratories (CMDL); Faculty of Associated Medical Sciences; Khon Kaen University; Thailand
- Department of Immunology National Institute of Infectious Diseases; Tokyo, Japan
| | - Donporn Riyapa
- The Cellular and Molecular Immunology Unit, the Center for Research and Development of Medical Diagnostic Laboratories (CMDL); Faculty of Associated Medical Sciences; Khon Kaen University; Thailand
| | - Surachat Buddhisa
- The Cellular and Molecular Immunology Unit, the Center for Research and Development of Medical Diagnostic Laboratories (CMDL); Faculty of Associated Medical Sciences; Khon Kaen University; Thailand
| | - Kusumawadee Utispan
- The Cellular and Molecular Immunology Unit, the Center for Research and Development of Medical Diagnostic Laboratories (CMDL); Faculty of Associated Medical Sciences; Khon Kaen University; Thailand
| | - Richard W Titball
- College of Life and Environmental Sciences; Biosciences; University of Exeter; Exeter, Devon, UK
| | - Mark P Stevens
- The Roslin Institute and Royal (Dick) School of Veterinary Studies; University of Edinburgh; UK
| | - Joanne M Stevens
- The Roslin Institute and Royal (Dick) School of Veterinary Studies; University of Edinburgh; UK
| | | | - Isei Tanida
- Department of Biochemistry and Cell Biology National Institute of Infectious Diseases; Tokyo, Japan
| | | | - Yasuo Uchiyama
- Department of Cellular and Molecular Neuropathology; Juntendo University Graduate School of Medicine; Tokyo, Japan
| | - Manabu Ato
- Department of Immunology National Institute of Infectious Diseases; Tokyo, Japan
| | - Ganjana Lertmemongkolchai
- The Cellular and Molecular Immunology Unit, the Center for Research and Development of Medical Diagnostic Laboratories (CMDL); Faculty of Associated Medical Sciences; Khon Kaen University; Thailand
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49
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Torres AG, Gregory AE, Hatcher CL, Vinet-Oliphant H, Morici LA, Titball RW, Roy CJ. Protection of non-human primates against glanders with a gold nanoparticle glycoconjugate vaccine. Vaccine 2014; 33:686-92. [PMID: 25533326 DOI: 10.1016/j.vaccine.2014.11.057] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 11/21/2014] [Accepted: 11/28/2014] [Indexed: 11/16/2022]
Abstract
The Gram-negative Burkholderia mallei is a zoonotic pathogen and the causative agent of glanders disease. Because the bacteria maintain the potential to be used as a biothreat agent, vaccine strategies are required for human glanders prophylaxis. A rhesus macaque (Macaca mulatta) model of pneumonic (inhalational) glanders was established and the protective properties of a nanoparticle glycoconjugate vaccine composed of Burkholderia thailandensis LPS conjugated to FliC was evaluated. An aerosol challenge dose of ∼1×10(4) CFU B. mallei produced mortality in 50% of naïve animals (n=2/4), 2-3 days post-exposure. Although survival benefit was not observed by vaccination with a glycoconjugate glanders vaccine (p=0.42), serum LPS-specific IgG titers were significantly higher on day 80 in 3 vaccinated animals who survived compared with 3 vaccinated animals who died. Furthermore, B. mallei was isolated from multiple organs of both non-vaccinated survivors, but not from any organs of 3 vaccinated survivors at 30 days post-challenge. Taken together, this is the first time a candidate vaccine has been evaluated in a non-human primate aerosol model of glanders and represents the initial step for consideration in pre-clinical studies.
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Affiliation(s)
- Alfredo G Torres
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA; Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA.
| | - Anthony E Gregory
- School of Biosciences, College of Life and Environmental Sciences, University of Exeter, Devon, UK
| | - Christopher L Hatcher
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Heather Vinet-Oliphant
- Division of Microbiology, Infectious Disease Aerobiology, Tulane National Primate Research Center, Covington, LA, USA
| | - Lisa A Morici
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Richard W Titball
- School of Biosciences, College of Life and Environmental Sciences, University of Exeter, Devon, UK
| | - Chad J Roy
- Division of Microbiology, Infectious Disease Aerobiology, Tulane National Primate Research Center, Covington, LA, USA; Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA, USA.
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Wagley S, Newcombe J, Laing E, Yusuf E, Sambles CM, Studholme DJ, La Ragione RM, Titball RW, Champion OL. Differences in carbon source utilisation distinguish Campylobacter jejuni from Campylobacter coli. BMC Microbiol 2014; 14:262. [PMID: 25348335 PMCID: PMC4219013 DOI: 10.1186/s12866-014-0262-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 10/02/2014] [Indexed: 12/02/2022] Open
Abstract
Background Campylobacter jejuni and C. coli are human intestinal pathogens that are the most frequent causes of bacterial foodborne gastroenteritis in humans in the UK. In this study, we aimed to characterise the metabolic diversity of both C. jejuni and C. coli using a diverse panel of clinical strains isolated from the UK, Pakistan and Thailand, thereby representing both the developed and developing world. Our aim was to apply multi genome analysis and Biolog phenotyping to determine differences in carbon source utilisation by C. jejuni and C. coli strains. Results We have identified a core set of carbon sources (utilised by all strains tested) and a set that are differentially utilised for a diverse panel of thirteen C. jejuni and two C. coli strains. This study used multi genome analysis to show that propionic acid is utilised only by C. coli strains tested. A broader PCR screen of 16 C. coli strains and 42 C. jejuni confirmed the absence of the genes needed for propanoate metabolism. Conclusions From our analysis we have identified a phenotypic method and two genotypic methods based on propionic utilisation that might be applicable for distinguishing between C. jejuni and C. coli. Electronic supplementary material The online version of this article (doi:10.1186/s12866-014-0262-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sariqa Wagley
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK.
| | - Jane Newcombe
- Faculty of Health and Medical Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, Surrey, GU2 7XH, UK.
| | - Emma Laing
- Faculty of Health and Medical Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, Surrey, GU2 7XH, UK.
| | - Emmanuel Yusuf
- Faculty of Health and Medical Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, Surrey, GU2 7XH, UK.
| | - Christine M Sambles
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK.
| | - David J Studholme
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK.
| | - Roberto M La Ragione
- Faculty of Health and Medical Sciences, School of Veterinary Medicine, University of Surrey, Guildford, Surrey, GU2 7XH, UK. .,Department of Bacteriology, Animal Health and Veterinary Laboratories Agency, Weybridge, Surrey, KT15 3NB, UK.
| | - Richard W Titball
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK.
| | - Olivia L Champion
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK.
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