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Kameli N, Basode VK, Abdulhaq A, Alamoudi MUA, Zain KAM, Ghzwani AH. Prevalence of toxigenic Clostridium difficile in hospitalized patients in the southwestern province of Saudi Arabia: Confirmation using the GeneXpert analysis. Libyan J Med 2024; 19:2294571. [PMID: 38112195 DOI: 10.1080/19932820.2023.2294571] [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: 06/15/2023] [Accepted: 12/09/2023] [Indexed: 12/21/2023] Open
Abstract
Clostridium difficile (Clostridioides difficile) is a leading cause of nosocomial infections in hospitalized patients worldwide. Stool samples were collected from 112 inpatients admitted to different hospitals and were screened for C. difficile GDH + toxin A + B by immunoassay, and all positive samples by immunoassay were processed for molecular detection of C. difficile using the GeneXpert assay. C. difficile strains were detected in 12 (10.71%) out of 112 stool samples using the GDH + toxin A + B immunoassay method and toxigenic C. difficile was confirmed in 5 stool samples using the GeneXpert molecular assay. C. difficile strains were also detected in 7 (8.97%) out of 78 stool samples from intensive care unit patients, 3 (25%) out of 12 stool samples from internal medicine ward patients, 1 (11.11%) out of 9 stool samples from surgery ward patients, and 1 (10%) out of 10 stool samples from isolation ward patients using the GDH + toxin A + B immunoassay method and the toxigenic C. difficile strain was confirmed in 1, 2, 1, and 1 stool samples, respectively, using the GeneXpert molecular assay. Toxigenic C. difficile was confirmed in patients at 4 (51.14%) out of 7 hospitals. In the present study, we also analyzed the clinical information of patients with C. difficile-positive stool samples who were receiving one or more antibiotics during hospitalization. The binary toxin gene (cdt), the tcdC gene, and the C. difficile strain polymerase chain reaction (PCR) ribotype 027 were not detected using the GeneXpert molecular assay among 12 C. difficile-positive samples by immunoassay. This study should aid in the prevention of unnecessary empiric therapy and increase the understanding of the toxigenic C. difficile burden on the healthcare system in the southwestern province of Saudi Arabia.
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Affiliation(s)
| | | | - Ahmed Abdulhaq
- Unit of Medical Microbiology, Department of Medical Lab Technology, Faculty of Applied Medical Sciences, Jazan University, Jazan, Kingdom of Saudi Arabia
| | - Mohammed Uthman A Alamoudi
- Unit of Medical Microbiology, Department of Medical Lab Technology, Faculty of Applied Medical Sciences, Jazan University, Jazan, Kingdom of Saudi Arabia
| | - Khalid Amaash Mohammed Zain
- Unit of Medical Microbiology, Department of Medical Lab Technology, Faculty of Applied Medical Sciences, Jazan University, Jazan, Kingdom of Saudi Arabia
| | - Ahmad Hassn Ghzwani
- Unit of Medical Microbiology, Department of Medical Lab Technology, Faculty of Applied Medical Sciences, Jazan University, Jazan, Kingdom of Saudi Arabia
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Camargo A, Ramírez JD, Kiu R, Hall LJ, Muñoz M. Unveiling the pathogenic mechanisms of Clostridium perfringens toxins and virulence factors. Emerg Microbes Infect 2024; 13:2341968. [PMID: 38590276 PMCID: PMC11057404 DOI: 10.1080/22221751.2024.2341968] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Accepted: 04/06/2024] [Indexed: 04/10/2024]
Abstract
Clostridium perfringens causes multiple diseases in humans and animals. Its pathogenic effect is supported by a broad and heterogeneous arsenal of toxins and other virulence factors associated with a specific host tropism. Molecular approaches have indicated that most C. perfringens toxins produce membrane pores, leading to osmotic cell disruption and apoptosis. However, identifying mechanisms involved in cell tropism and selective toxicity effects should be studied more. The differential presence and polymorphisms of toxin-encoding genes and genes encoding other virulence factors suggest that molecular mechanisms might exist associated with host preference, receptor binding, and impact on the host; however, this information has not been reviewed in detail. Therefore, this review aims to clarify the current state of knowledge on the structural features and mechanisms of action of the major toxins and virulence factors of C. perfringens and discuss the impact of genetic diversity of toxinotypes in tropism for several hosts.
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Affiliation(s)
- Anny Camargo
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
- Health Sciences Faculty, Universidad de Boyacá, Tunja, Colombia
| | - Juan David Ramírez
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
- Molecular Microbiology Laboratory, Department of Pathology, Molecular and Cell-Based Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Raymond Kiu
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
- Gut Microbes and Health, Quadram Institute Bioscience, Norwich Research Park, Norwich, UK
| | - Lindsay J. Hall
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
- Gut Microbes and Health, Quadram Institute Bioscience, Norwich Research Park, Norwich, UK
- Norwich Medical School, University of East Anglia, Norwich, UK
| | - Marina Muñoz
- Centro de Investigaciones en Microbiología y Biotecnología-UR (CIMBIUR), Facultad de Ciencias Naturales, Universidad del Rosario, Bogotá, Colombia
- Instituto de Biotecnología-UN (IBUN), Universidad Nacional de Colombia, Bogotá, Colombia
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Inagaki R, Koshiba A, Nasuno E, Kato N. Eliminating extracellular autoinducing peptide signals inhibits the Staphylococcus aureus quorum sensing agr system. Biochem Biophys Res Commun 2024; 711:149912. [PMID: 38615572 DOI: 10.1016/j.bbrc.2024.149912] [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: 03/11/2024] [Accepted: 04/05/2024] [Indexed: 04/16/2024]
Abstract
An accessory gene regulator (agr) in the quorum sensing (QS) system in Staphylococcus aureus contributes to host infection, virulence factor production, and resistance to oxidative damage. Artificially maintaining the inactive state of agr QS impedes the host infection strategy of S. aureus and inhibits toxin production. The QS system performs intercellular signal transduction, which is activated by the mature autoinducer peptide (AIP). It is released from cells after AgrD peptide processing as an intercellular signal associated with increased bacterial cell density. This study evaluated the effectiveness of inhibiting agr QS wherein AIP trap carriers were made to coexist when culturing Staphylococcus aureus. Immersing a nitrocellulose (NC) membrane in Staphylococcus aureus ATCC 12600 culture inhibited QS-dependent α-hemolysin production, which significantly reduced the hemolysis ratio of sheep red blood cells by the culture supernatant. A quartz crystal microbalance analysis supported AIP adsorption onto the NC membrane. Adding the NC membrane during culture was found to maintain the expression levels of the agr QS gene agrA and α-hemolysin gene hla lower than that when it was not added. Eliminating extracellular AIP signals allowed agr QS to remain inactive and prevented QS-dependent α-hemolysin expression. Isolating intercellular signals secreted outside the cell is an effective strategy to suppress gene expression in bacterial cells that collaborate via intercellular signaling.
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Affiliation(s)
- Ruki Inagaki
- Graduate School of Regional Development and Creativity, Utsunomiya University, 7-1-2 Yoto, Utsunomiya, Tochigi, 321-8585, Japan
| | - Ayaka Koshiba
- Graduate School of Regional Development and Creativity, Utsunomiya University, 7-1-2 Yoto, Utsunomiya, Tochigi, 321-8585, Japan
| | - Eri Nasuno
- Graduate School of Regional Development and Creativity, Utsunomiya University, 7-1-2 Yoto, Utsunomiya, Tochigi, 321-8585, Japan.
| | - Norihiro Kato
- Graduate School of Regional Development and Creativity, Utsunomiya University, 7-1-2 Yoto, Utsunomiya, Tochigi, 321-8585, Japan.
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Frentzel H, Kraemer M, Kelner-Burgos Y, Uelze L, Bodi D. Cereulide production capacities and genetic properties of 31 emetic Bacillus cereus group strains. Int J Food Microbiol 2024; 417:110694. [PMID: 38614024 DOI: 10.1016/j.ijfoodmicro.2024.110694] [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: 11/28/2023] [Revised: 04/02/2024] [Accepted: 04/05/2024] [Indexed: 04/15/2024]
Abstract
The highly potent toxin cereulide is a frequent cause of foodborne intoxications. This extremely resistant toxin is produced by Bacillus cereus group strains carrying the plasmid encoded cesHPTABCD gene cluster. It is known that the capacities to produce cereulide vary greatly between different strains but the genetic background of these variations is not clear. In this study, cereulide production capacities were associated with genetic characteristics. For this, cereulide levels in cultures of 31 strains were determined after incubation in tryptic soy broth for 24 h at 24 °C, 30 °C and 37 °C. Whole genome sequencing based data were used for an in-depth characterization of gene sequences related to cereulide production. The taxonomy, population structure and phylogenetic relationships of the strains were evaluated based on average nucleotide identity, multi-locus sequence typing (MLST), core genome MLST and single nucleotide polymorphism analyses. Despite a limited strain number, the approach of a genome wide association study (GWAS) was tested to link genetic variation with cereulide quantities. Our study confirms strain-dependent differences in cereulide production. For most strains, these differences were not explainable by sequence variations in the cesHPTABCD gene cluster or the regulatory genes abrB, spo0A, codY and pagRBc. Likewise, the population structure and phylogeny of the tested strains did not comprehensively reflect the cereulide production capacities. GWAS yielded first hints for associated proteins, while their possible effect on cereulide synthesis remains to be further investigated.
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Affiliation(s)
- Hendrik Frentzel
- German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589 Berlin, Germany.
| | - Marco Kraemer
- German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589 Berlin, Germany
| | - Ylanna Kelner-Burgos
- German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589 Berlin, Germany
| | - Laura Uelze
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Sequencing and Genotyping Service Unit, Pfotenhauerstraße 108, 01307 Dresden, Germany
| | - Dorina Bodi
- German Federal Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589 Berlin, Germany
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Lu W, Zhao X, Li M, Li Y, Zhang C, Xiong Y, Li J, Zhou H, Ye X, Li X, Wang J, Liang X, Qing G. Precise Structural Analysis of Neutral Glycans Using Aerolysin Mutant T240R Nanopore. ACS Nano 2024; 18:12412-12426. [PMID: 38693619 DOI: 10.1021/acsnano.4c01571] [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] [Subscribe] [Scholar Register] [Indexed: 05/03/2024]
Abstract
Glycans play vital roles in nearly all life processes of multicellular organisms, and understanding these activities is inseparable from elucidating the biological significance of glycans. However, glycan research has lagged behind that of DNA and protein due to the challenges posed by structural heterogeneity and isomerism (i.e., structures with equal molecular weights) the lack of high-efficiency structural analysis techniques. Nanopore technology has emerged as a sensitive single-molecule biosensor, shining a light on glycan analysis. However, a significant number of glycans are small and uncharged, making it challenging to elicit identifiable nanopore signals. Here we introduce a R-binaphthyl tag into glycans, which enhances the cation-π interaction between the derivatized glycan molecules and the nanopore interface, enabling the detection of neutral glycans with an aerolysin nanopore. This approach allows for the distinction of di-, tri-, and tetrasaccharides with monosaccharide resolution and has the potential for group discrimination, the monitoring of enzymatic transglycosylation reactions. Notably, the aerolysin mutant T240R achieves unambiguous identification of six disaccharide isomers, trisaccharide and tetrasaccharide linkage isomers. Molecular docking simulations reveal that multiple noncovalent interactions occur between residues R282, K238, and R240 and the glycans and R-binaphthyl tag, significantly slowing down their translocation across the nanopore. Importantly, we provide a demonstration of the kinetic translocation process of neutral glycan isomers, establishing a solid theoretical foundation for glycan nanopore analysis. The development of our technology could promote the analysis of glycan structural isomers and has the potential for nanopore-based glycan structural determination and sequencing.
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Affiliation(s)
- Wenqi Lu
- State Key Laboratory of Medical Proteomics, National Chromatographic R. & A. Center, CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Xinjia Zhao
- State Key Laboratory of Medical Proteomics, National Chromatographic R. & A. Center, CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Minmin Li
- State Key Laboratory of Medical Proteomics, National Chromatographic R. & A. Center, CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Yuting Li
- Jiangxi Provincial Key Laboratory for Pharmacodynamic Material Basis of Traditional Chinese Medicine, Ganjiang Chinese Medicine Innovation Center, Nanchang 330000, P. R. China
| | - Chen Zhang
- Jiangxi Provincial Key Laboratory for Pharmacodynamic Material Basis of Traditional Chinese Medicine, Ganjiang Chinese Medicine Innovation Center, Nanchang 330000, P. R. China
| | - Yuting Xiong
- State Key Laboratory of Medical Proteomics, National Chromatographic R. & A. Center, CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Jiaqi Li
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Han Zhou
- Jiangxi Provincial Key Laboratory for Pharmacodynamic Material Basis of Traditional Chinese Medicine, Ganjiang Chinese Medicine Innovation Center, Nanchang 330000, P. R. China
| | - Xianlong Ye
- Jiangxi Provincial Key Laboratory for Pharmacodynamic Material Basis of Traditional Chinese Medicine, Ganjiang Chinese Medicine Innovation Center, Nanchang 330000, P. R. China
| | - Xiaonong Li
- Jiangxi Provincial Key Laboratory for Pharmacodynamic Material Basis of Traditional Chinese Medicine, Ganjiang Chinese Medicine Innovation Center, Nanchang 330000, P. R. China
| | - Jing Wang
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Xinmiao Liang
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
- Jiangxi Provincial Key Laboratory for Pharmacodynamic Material Basis of Traditional Chinese Medicine, Ganjiang Chinese Medicine Innovation Center, Nanchang 330000, P. R. China
| | - Guangyan Qing
- State Key Laboratory of Medical Proteomics, National Chromatographic R. & A. Center, CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
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Garrine M, Andrade M, Neves J, Mandomando I, Couto I, Costa SS. Exploring the virulence potential of Staphylococcus aureus CC121 and CC152 lineages related to paediatric community-acquired bacteraemia in Manhiça, Mozambique. Sci Rep 2024; 14:10758. [PMID: 38730020 PMCID: PMC11087594 DOI: 10.1038/s41598-024-61345-3] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 05/05/2024] [Indexed: 05/12/2024] Open
Abstract
Staphylococcus aureus is a frequent agent of bacteraemia. This bacterium has a variety of virulence traits that allow the establishment and maintenance of infection. This study explored the virulence profile of S. aureus strains causing paediatric bacteraemia (SAB) in Manhiça district, Mozambique. We analysed 336 S. aureus strains isolated from blood cultures of children younger than 5 years admitted to the Manhiça District Hospital between 2001 and 2019, previously characterized for antibiotic susceptibility and clonality. The strains virulence potential was evaluated by PCR detection of the Panton-Valentine leucocidin (PVL) encoding genes, lukS-PV/lukF-PV, assessment of the capacity for biofilm formation and pathogenicity assays in Galleria mellonella. The overall carriage of PVL-encoding genes was over 40%, although reaching ~ 70 to 100% in the last years (2014 to 2019), potentially linked to the emergence of CC152 lineage. Strong biofilm production was a frequent trait of CC152 strains. Representative CC152 and CC121 strains showed higher virulence potential in the G. mellonella model when compared to reference strains, with variations within and between CCs. Our results highlight the importance of monitoring the emergent CC152-MSSA-PVL+ and other lineages, as they display important virulence traits that may negatively impact the management of SAB paediatric patients in Manhiça district, Mozambique.
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Affiliation(s)
- Marcelino Garrine
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Rua da Junqueira 100, 1349-008, Lisbon, Portugal
| | - Mariana Andrade
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Rua da Junqueira 100, 1349-008, Lisbon, Portugal
| | - Joana Neves
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Rua da Junqueira 100, 1349-008, Lisbon, Portugal
| | - Inácio Mandomando
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Rua da Junqueira 100, 1349-008, Lisbon, Portugal
- Instituto Nacional de Saúde (INS), Ministério da Saúde, Maputo, Mozambique
- ISGlobal-Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
| | - Isabel Couto
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Rua da Junqueira 100, 1349-008, Lisbon, Portugal
| | - Sofia Santos Costa
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Rua da Junqueira 100, 1349-008, Lisbon, Portugal.
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Abo Elyazeed H, Elhariri M, Eldeen NE, Aziz DA, Elhelw R. Genetic diversity and phylogenetic relationships of Clostridium perfringens strains isolated from mastitis and enteritis in Egyptian dairy farms. BMC Microbiol 2024; 24:157. [PMID: 38710998 DOI: 10.1186/s12866-024-03260-1] [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: 10/15/2023] [Accepted: 03/14/2024] [Indexed: 05/08/2024] Open
Abstract
BACKGROUND Clostridium perfringens, a common environmental bacterium, is responsible for a variety of serious illnesses including food poisoning, digestive disorders, and soft tissue infections. Mastitis in lactating cattle and sudden death losses in baby calves are major problems for producers raising calves on dairy farms. The pathogenicity of this bacterium is largely mediated by its production of various toxins. RESULTS The study revealed that Among the examined lactating animals with a history of mastitis, diarrheal baby calves, and acute sudden death cases in calves, C. perfringens was isolated in 23.5% (93/395) of the total tested samples. Eighteen isolates were obtained from mastitic milk, 59 from rectal swabs, and 16 from the intestinal contents of dead calves. Most of the recovered C. perfringens isolates (95.6%) were identified as type A by molecular toxinotyping, except for four isolates from sudden death cases (type C). Notably, C. perfringens was recovered in 100% of sudden death cases compared with 32.9% of rectal swabs and 9% of milk samples. This study analyzed the phylogeny of C. perfringens using the plc region and identified the plc region in five Egyptian bovine isolates (milk and fecal origins). Importantly, this finding expands the known data on C. perfringens phospholipase C beyond reference strains in GenBank from various animal and environmental sources. CONCLUSION Phylogenetic analyses of nucleotide sequence data differentiated between strains of different origins. The plc sequences of Egyptian C. perfringens strains acquired in the present study differed from those reported globally and constituted a distinct genetic ancestor.
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Affiliation(s)
- Heidy Abo Elyazeed
- Microbiology and Immunology Department, Faculty of Veterinary Medicine, Cairo University, Giza, 12211, Egypt
| | - Mahmoud Elhariri
- Microbiology and Immunology Department, Faculty of Veterinary Medicine, Cairo University, Giza, 12211, Egypt.
| | - Nashwa Ezz Eldeen
- Microbiology and Immunology Department, Faculty of Veterinary Medicine, Cairo University, Giza, 12211, Egypt
- Biology Department, Faculty of Science - Taif University, Taif, Saudi Arabia
| | - Dalal Ahmed Aziz
- Microbiology and Immunology Department, Faculty of Veterinary Medicine, Cairo University, Giza, 12211, Egypt
| | - Rehab Elhelw
- Microbiology and Immunology Department, Faculty of Veterinary Medicine, Cairo University, Giza, 12211, Egypt
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Takashima Y, Kawamura H, Okadome K, Ugai S, Haruki K, Arima K, Mima K, Akimoto N, Nowak JA, Giannakis M, Garrett WS, Sears CL, Song M, Ugai T, Ogino S. Enrichment of Bacteroides fragilis and enterotoxigenic Bacteroides fragilis in CpG island methylator phenotype-high colorectal carcinoma. Clin Microbiol Infect 2024; 30:630-636. [PMID: 38266708 DOI: 10.1016/j.cmi.2024.01.013] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 12/04/2023] [Accepted: 01/13/2024] [Indexed: 01/26/2024]
Abstract
OBJECTIVES Data support that enterotoxigenic Bacteroides fragilis (ETBF) harbouring the Bacteroides fragilis toxin (bft) gene may promote colorectal tumourigenesis through the serrated neoplasia pathway. We hypothesized that ETBF may be enriched in colorectal carcinoma subtypes with high-level CpG island methylator phenotype (CIMP-high), BRAF mutation, and high-level microsatellite instability (MSI-high). METHODS Quantitative PCR assays were designed to quantify DNA amounts of Bacteroides fragilis, ETBF, and each bft gene isotype (bft-1, bft-2, or bft-3) in colorectal carcinomas in the Health Professionals Follow-up Study and Nurses' Health Study. We used multivariable-adjusted logistic regression models with the inverse probability weighting method. RESULTS We documented 4476 colorectal cancer cases, including 1232 cases with available bacterial data. High DNA amounts of Bacteroides fragilis and ETBF were positively associated with BRAF mutation (p ≤ 0.0003), CIMP-high (p ≤ 0.0002), and MSI-high (p < 0.0001 and p = 0.01, respectively). Multivariable-adjusted odds ratios (with 95% confidence interval) for high Bacteroides fragilis were 1.40 (1.06-1.85) for CIMP-high and 2.14 (1.65-2.77) for MSI-high, but 1.02 (0.78-1.35) for BRAF mutation. Multivariable-adjusted odds ratios for high ETBF were 2.00 (1.16-3.45) for CIMP-high and 2.86 (1.64-5.00) for BRAF mutation, but 1.09 (0.67-1.76) for MSI-high. Neither Bacteroides fragilis nor ETBF was associated with colorectal cancer-specific or overall survival. DISCUSSION The tissue abundance of Bacteroides fragilis is associated with CIMP-high and MSI-high, whereas ETBF abundance is associated with CIMP-high and BRAF mutation in colorectal carcinoma. Our findings support the aetiological relevance of Bacteroides fragilis and ETBF in the serrated neoplasia pathway.
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Affiliation(s)
- Yasutoshi Takashima
- Program in MPE Molecular Pathological Epidemiology, Department of Pathology, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA, USA; Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA, USA
| | - Hidetaka Kawamura
- Program in MPE Molecular Pathological Epidemiology, Department of Pathology, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA, USA
| | - Kazuo Okadome
- Program in MPE Molecular Pathological Epidemiology, Department of Pathology, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA, USA
| | - Satoko Ugai
- Program in MPE Molecular Pathological Epidemiology, Department of Pathology, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA, USA; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Koichiro Haruki
- Program in MPE Molecular Pathological Epidemiology, Department of Pathology, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA, USA
| | - Kota Arima
- Program in MPE Molecular Pathological Epidemiology, Department of Pathology, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA, USA
| | - Kosuke Mima
- Program in MPE Molecular Pathological Epidemiology, Department of Pathology, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA, USA
| | - Naohiko Akimoto
- Program in MPE Molecular Pathological Epidemiology, Department of Pathology, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA, USA
| | - Jonathan A Nowak
- Program in MPE Molecular Pathological Epidemiology, Department of Pathology, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA, USA; Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA, USA
| | - Marios Giannakis
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA, USA; Broad Institute of MIT and Harvard, Cambridge, MA, USA; Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Wendy S Garrett
- Department of Medical Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA, USA; Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Cynthia L Sears
- Division of Infectious Diseases, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Bloomberg-Kimmel Institute for Cancer Immunotherapy, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Mingyang Song
- Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Clinical and Translational Epidemiology Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Division of Gastroenterology, Massachusetts General Hospital, Boston, MA, USA
| | - Tomotaka Ugai
- Program in MPE Molecular Pathological Epidemiology, Department of Pathology, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA, USA; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Shuji Ogino
- Program in MPE Molecular Pathological Epidemiology, Department of Pathology, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA, USA; Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA; Broad Institute of MIT and Harvard, Cambridge, MA, USA; Cancer Immunology Program, Dana-Farber Harvard Cancer Centre, Boston, MA, USA.
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Zhao Q, Bertolli S, Park YJ, Tan Y, Cutler KJ, Srinivas P, Asfahl KL, Fonesca-García C, Gallagher LA, Li Y, Wang Y, Coleman-Derr D, DiMaio F, Zhang D, Peterson SB, Veesler D, Mougous JD. Streptomyces umbrella toxin particles block hyphal growth of competing species. Nature 2024; 629:165-173. [PMID: 38632398 PMCID: PMC11062931 DOI: 10.1038/s41586-024-07298-z] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 03/11/2024] [Indexed: 04/19/2024]
Abstract
Streptomyces are a genus of ubiquitous soil bacteria from which the majority of clinically utilized antibiotics derive1. The production of these antibacterial molecules reflects the relentless competition Streptomyces engage in with other bacteria, including other Streptomyces species1,2. Here we show that in addition to small-molecule antibiotics, Streptomyces produce and secrete antibacterial protein complexes that feature a large, degenerate repeat-containing polymorphic toxin protein. A cryo-electron microscopy structure of these particles reveals an extended stalk topped by a ringed crown comprising the toxin repeats scaffolding five lectin-tipped spokes, which led us to name them umbrella particles. Streptomyces coelicolor encodes three umbrella particles with distinct toxin and lectin composition. Notably, supernatant containing these toxins specifically and potently inhibits the growth of select Streptomyces species from among a diverse collection of bacteria screened. For one target, Streptomyces griseus, inhibition relies on a single toxin and that intoxication manifests as rapid cessation of vegetative hyphal growth. Our data show that Streptomyces umbrella particles mediate competition among vegetative mycelia of related species, a function distinct from small-molecule antibiotics, which are produced at the onset of reproductive growth and act broadly3,4. Sequence analyses suggest that this role of umbrella particles extends beyond Streptomyces, as we identified umbrella loci in nearly 1,000 species across Actinobacteria.
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Affiliation(s)
- Qinqin Zhao
- Department of Microbiology, University of Washington, Seattle, WA, USA
| | - Savannah Bertolli
- Department of Microbiology, University of Washington, Seattle, WA, USA
| | - Young-Jun Park
- Howard Hughes Medical Institute, University of Washington, Seattle, WA, USA
- Department of Biochemistry, University of Washington, Seattle, WA, USA
| | - Yongjun Tan
- Department of Biology, St Louis University, St Louis, MO, USA
| | - Kevin J Cutler
- Department of Microbiology, University of Washington, Seattle, WA, USA
- Department of Physics, University of Washington, Seattle, WA, USA
| | - Pooja Srinivas
- Department of Microbiology, University of Washington, Seattle, WA, USA
| | - Kyle L Asfahl
- Department of Microbiology, University of Washington, Seattle, WA, USA
- Microbial Interactions and Microbiome Center, University of Washington, Seattle, WA, USA
| | - Citlali Fonesca-García
- Plant Gene Expression Center, USDA-ARS, Albany, CA, USA
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA, USA
| | - Larry A Gallagher
- Department of Microbiology, University of Washington, Seattle, WA, USA
| | - Yaqiao Li
- Department of Microbiology, University of Washington, Seattle, WA, USA
| | - Yaxi Wang
- Department of Microbiology, University of Washington, Seattle, WA, USA
| | - Devin Coleman-Derr
- Plant Gene Expression Center, USDA-ARS, Albany, CA, USA
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA, USA
| | - Frank DiMaio
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Dapeng Zhang
- Department of Biology, St Louis University, St Louis, MO, USA
- Program of Bioinformatic and Computational Biology, St Louis University, St Louis, MO, USA
| | - S Brook Peterson
- Department of Microbiology, University of Washington, Seattle, WA, USA
| | - David Veesler
- Howard Hughes Medical Institute, University of Washington, Seattle, WA, USA
- Department of Biochemistry, University of Washington, Seattle, WA, USA
| | - Joseph D Mougous
- Department of Microbiology, University of Washington, Seattle, WA, USA.
- Howard Hughes Medical Institute, University of Washington, Seattle, WA, USA.
- Microbial Interactions and Microbiome Center, University of Washington, Seattle, WA, USA.
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10
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Busby JN, Trevelyan S, Pegg CL, Kerr ED, Schulz BL, Chassagnon I, Landsberg MJ, Weston MK, Hurst MRH, Lott JS. The ABC toxin complex from Yersinia entomophaga can package three different cytotoxic components expressed from distinct genetic loci in an unfolded state: the structures of both shell and cargo. IUCrJ 2024; 11:299-308. [PMID: 38512773 PMCID: PMC11067744 DOI: 10.1107/s2052252524001969] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 02/28/2024] [Indexed: 03/23/2024]
Abstract
Bacterial ABC toxin complexes (Tcs) comprise three core proteins: TcA, TcB and TcC. The TcA protein forms a pentameric assembly that attaches to the surface of target cells and penetrates the cell membrane. The TcB and TcC proteins assemble as a heterodimeric TcB-TcC subcomplex that makes a hollow shell. This TcB-TcC subcomplex self-cleaves and encapsulates within the shell a cytotoxic `cargo' encoded by the C-terminal region of the TcC protein. Here, we describe the structure of a previously uncharacterized TcC protein from Yersinia entomophaga, encoded by a gene at a distant genomic location from the genes encoding the rest of the toxin complex, in complex with the TcB protein. When encapsulated within the TcB-TcC shell, the C-terminal toxin adopts an unfolded and disordered state, with limited areas of local order stabilized by the chaperone-like inner surface of the shell. We also determined the structure of the toxin cargo alone and show that when not encapsulated within the shell, it adopts an ADP-ribosyltransferase fold most similar to the catalytic domain of the SpvB toxin from Salmonella typhimurium. Our structural analysis points to a likely mechanism whereby the toxin acts directly on actin, modifying it in a way that prevents normal polymerization.
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Affiliation(s)
- Jason N. Busby
- School of Biological Sciences, University of Auckland, Auckland 1142, New Zealand
| | - Sarah Trevelyan
- School of Biological Sciences, University of Auckland, Auckland 1142, New Zealand
| | - Cassandra L. Pegg
- School of Chemistry and Molecular Biosciences, University of Central Queensland, Brisbane, Queensland 4072, Australia
| | - Edward D. Kerr
- School of Chemistry and Molecular Biosciences, University of Central Queensland, Brisbane, Queensland 4072, Australia
| | - Benjamin L. Schulz
- School of Chemistry and Molecular Biosciences, University of Central Queensland, Brisbane, Queensland 4072, Australia
| | - Irene Chassagnon
- School of Chemistry and Molecular Biosciences, University of Central Queensland, Brisbane, Queensland 4072, Australia
| | - Michael J. Landsberg
- School of Chemistry and Molecular Biosciences, University of Central Queensland, Brisbane, Queensland 4072, Australia
| | - Mitchell K. Weston
- Resilient Agriculture, AgResearch, Lincoln Research Centre, Christchurch 8140, New Zealand
| | - Mark R. H. Hurst
- Resilient Agriculture, AgResearch, Lincoln Research Centre, Christchurch 8140, New Zealand
| | - J. Shaun Lott
- School of Biological Sciences, University of Auckland, Auckland 1142, New Zealand
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Mehdizadeh Gohari I, Gonzales JL, Uzal FA, McClane BA. Overexpressing the cpr1953 Orphan Histidine Kinase Gene in the Absence of cpr1954 Orphan Histidine Kinase Gene Expression, or Vice Versa, Is Sufficient to Obtain Significant Sporulation and Strong Production of Clostridium perfringens Enterotoxin or Spo0A by Clostridium perfringens Type F Strain SM101. Toxins (Basel) 2024; 16:195. [PMID: 38668620 PMCID: PMC11053440 DOI: 10.3390/toxins16040195] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 04/03/2024] [Accepted: 04/10/2024] [Indexed: 04/29/2024] Open
Abstract
The CPR1953 and CPR1954 orphan histidine kinases profoundly affect sporulation initiation and Clostridium perfringens enterotoxin (CPE) production by C. perfringens type F strain SM101, whether cultured in vitro (modified Duncan-Strong sporulation medium (MDS)) or ex vivo (mouse small intestinal contents (MIC)). To help distinguish whether CPR1953 and CPR1954 act independently or in a stepwise manner to initiate sporulation and CPE production, cpr1953 and cpr1954 null mutants of SM101 were transformed with plasmids carrying the cpr1954 or cpr1953 genes, respectively, causing overexpression of cpr1954 in the absence of cpr1953 expression and vice versa. RT-PCR confirmed that, compared to SM101, the cpr1953 mutant transformed with a plasmid encoding cpr1954 expressed cpr1954 at higher levels while the cpr1954 mutant transformed with a plasmid encoding cpr1953 expressed higher levels of cpr1953. Both overexpressing strains showed near wild-type levels of sporulation, CPE toxin production, and Spo0A production in MDS or MIC. These findings suggest that CPR1953 and CPR1954 do not function together in a step-wise manner, e.g., as a novel phosphorelay. Instead, it appears that, at natural expression levels, the independent kinase activities of both CPR1953 and CPR1954 are necessary for obtaining sufficient Spo0A production and phosphorylation to initiate sporulation and CPE production.
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Affiliation(s)
- Iman Mehdizadeh Gohari
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15219, USA;
| | - Jessica L. Gonzales
- California Animal Health and Food Safety Laboratory System, School of Veterinary Medicine, University of California Davis, San Bernardino, CA 92408, USA; (J.L.G.); (F.A.U.)
| | - Francisco A. Uzal
- California Animal Health and Food Safety Laboratory System, School of Veterinary Medicine, University of California Davis, San Bernardino, CA 92408, USA; (J.L.G.); (F.A.U.)
| | - Bruce A. McClane
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15219, USA;
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Boesze-Battaglia K, Cohen GH, Bates PF, Walker LM, Zekavat A, Shenker BJ. Cellugyrin (synaptogyrin-2) dependent pathways are used by bacterial cytolethal distending toxin and SARS-CoV-2 virus to gain cell entry. Front Cell Infect Microbiol 2024; 14:1334224. [PMID: 38698905 PMCID: PMC11063343 DOI: 10.3389/fcimb.2024.1334224] [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] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 03/19/2024] [Indexed: 05/05/2024] Open
Abstract
Aggregatibacter actinomycetemcomitans cytolethal distending toxin (Cdt) is capable of intoxicating lymphocytes macrophages, mast cells and epithelial cells. Following Cdt binding to cholesterol, in the region of membrane lipid rafts, the CdtB and CdtC subunits are internalized and traffic to intracellular compartments. These events are dependent upon, cellugyrin, a critical component of synaptic like microvesicles (SLMVCg+). Target cells, such as Jurkat cells, rendered unable to express cellugyrin are resistant to Cdt-induced toxicity. Similar to Cdt, SARS-CoV-2 entry into host cells is initiated by binding to cell surface receptors, ACE-2, also associated with cholesterol-rich lipid rafts; this association leads to fusion and/or endocytosis of viral and host cell membranes and intracellular trafficking. The similarity in internalization pathways for both Cdt and SARS-CoV-2 led us to consider the possibility that cellugyrin was a critical component in both processes. Cellugyrin deficient Calu-3 cells (Calu-3Cg-) were prepared using Lentiviral particles containing shRNA; these cells were resistant to infection by VSV/SARS-CoV-2-spike pseudotype virus and partially resistant to VSV/VSV-G pseudotype virus. Synthetic peptides representing various regions of the cellugyrin protein were prepared and assessed for their ability to bind to Cdt subunits using surface plasmon resonance. Cdt was capable of binding to a region designated the middle outer loop (MOL) which corresponds to a region extending into the cytoplasmic surface of the SLMVCg+. SARS-CoV-2 spike proteins were assessed for their ability to bind to cellugyrin peptides; SARS-CoV-2 full length spike protein preferentially binds to a region within the SLMVCg+ lumen, designated intraluminal loop 1A. SARS-CoV-2-spike protein domain S1, which contains the receptor binding domains, binds to cellugyrin N-terminus which extends out from the cytoplasmic surface of SLMV. Binding specificity was further analyzed using cellugyrin scrambled peptide mutants. We propose that SLMVCg+ represent a component of a common pathway that facilitates pathogen and/or pathogen-derived toxins to gain host cell entry.
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Affiliation(s)
- Kathleen Boesze-Battaglia
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Gary H. Cohen
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Paul F. Bates
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Lisa M. Walker
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Ali Zekavat
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Bruce J. Shenker
- Department of Basic and Translational Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
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Chemello AJ, Fowler CC. Alternate typhoid toxin assembly evolved independently in the two Salmonella species. mBio 2024; 15:e0340323. [PMID: 38501873 PMCID: PMC11005416 DOI: 10.1128/mbio.03403-23] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 02/23/2024] [Indexed: 03/20/2024] Open
Abstract
AB5-type toxins are a diverse family of protein toxins composed of an enzymatic active (A) subunit and a pentameric delivery (B) subunit. Salmonella enterica serovar Typhi's typhoid toxin features two A subunits, CdtB and PltA, in complex with the B subunit PltB. Recently, it was shown that S. Typhi encodes a horizontally acquired B subunit, PltC, that also assembles with PltA/CdtB to produce a second form of typhoid toxin. S. Typhi therefore produces two AB5 toxins with the same A subunits but distinct B subunits, an evolutionary twist that is unique to typhoid toxin. Here, we show that, remarkably, the Salmonella bongori species independently evolved an analogous capacity to produce two typhoid toxins with distinct B subunits. S. bongori's alternate B subunit, PltD, is evolutionarily distant from both PltB and PltC and outcompetes PltB to form the predominant toxin. We show that, surprisingly, S. bongori elicits similar levels of CdtB-mediated intoxication as S. Typhi during infection of cultured human epithelial cells. This toxicity is exclusively due to the PltB toxin, and strains lacking pltD produce increased amounts of PltB toxin and exhibit increased toxicity compared to the wild type, suggesting that the acquisition of the PltD subunit potentially made S. bongori less virulent toward humans. Collectively, this study unveils a striking example of convergent evolution that highlights the importance of the poorly understood "two-toxin" paradigm for typhoid toxin biology and, more broadly, illustrates how the flexibility of A-B interactions has fueled the evolutionary diversification and expansion of AB5-type toxins. IMPORTANCE Typhoid toxin is an important Salmonella Typhi virulence factor and an attractive target for therapeutic interventions to combat typhoid fever. The recent discovery of a second version of this toxin has substantial implications for understanding S. Typhi pathogenesis and combating typhoid fever. In this study, we discover that a remarkably similar two-toxin paradigm evolved independently in Salmonella bongori, which strongly suggests that this is a critical aspect of typhoid toxin biology. We observe significant parallels between how the two toxins assemble and their capacity to intoxicate host cells during infection in S. Typhi and S. bongori, which provides clues to the biological significance of this unusual toxin arrangement. More broadly, AB5 toxins with diverse activities and mechanisms are essential virulence factors for numerous important bacterial pathogens. This study illustrates the capacity for novel A-B interactions to evolve and thus provides insight into how such a diverse arsenal of toxins might have emerged.
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Affiliation(s)
- Antonio J. Chemello
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Casey C. Fowler
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
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14
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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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15
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Caro-Borrero A, Márquez-Santamaria K, Carmona-Jiménez J, Becerra-Absalón I, Perona E. Cyanobacterial Harmful Algal Mats (CyanoHAMs) in tropical rivers of central Mexico and their potential risks through toxin production. Environ Monit Assess 2024; 196:408. [PMID: 38561517 PMCID: PMC10984904 DOI: 10.1007/s10661-024-12568-4] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 03/23/2024] [Indexed: 04/04/2024]
Abstract
Cyanobacteria inhabiting lotic environments have been poorly studied and characterized in Mexico, despite their potential risks from cyanotoxin production. This article aims to fill this knowledge gap by assessing the importance of benthic cyanobacteria as potential cyanotoxin producers in central Mexican rivers through: (i) the taxonomic identification of cyanobacteria found in these rivers, (ii) the environmental characterization of their habitats, and (iii) testing for the presence of toxin producing genes in the encountered taxa. Additionally, we introduce and discuss the use of the term "CyanoHAMs" for lotic water environments. Populations of cyanobacteria were collected from ten mountain rivers and identified using molecular techniques. Subsequently, these taxa were evaluated for genes producing anatoxins and microcystins via PCR. Through RDA analyses, the collected cyanobacteria were grouped into one of three categories based on their environmental preferences for the following: (1) waters with high ionic concentrations, (2) cold-temperate waters, or (3) waters with high nutrient enrichment. Populations from six locations were identified to genus level: Ancylothrix sp., Cyanoplacoma sp., and Oxynema sp. The latter was found to contain the gene that produces anatoxins and microcystins in siliceous rivers, while Oxynema tested positive for the gene that produces microcystins in calcareous rivers. Our results suggest that eutrophic environments are not necessarily required for toxin-producing cyanobacteria. Our records of Compactonostoc, Oxynema, and Ancylothrix represent the first for Mexico. Four taxa were identified to species level: Wilmottia aff. murrayi, Nostoc tlalocii, Nostoc montejanii, and Dichothrix aff. willei, with only the first testing positive using PCR for anatoxin and microcystin-producing genes in siliceous rivers. Due to the differences between benthic growths with respect to planktonic ones, we propose the adoption of the term Cyanobacterial Harmful Algal Mats (CyanoHAMs) as a more precise descriptor for future studies.
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Affiliation(s)
- Angela Caro-Borrero
- Ecology and Natural Resources Department, Science Faculty, National Autonomous University of Mexico, University City, Exterior Circuit S/N, 04510, Coyoacan, Mexico City, Mexico
| | - Kenia Márquez-Santamaria
- Ecology and Natural Resources Department, Science Faculty, National Autonomous University of Mexico, University City, Exterior Circuit S/N, 04510, Coyoacan, Mexico City, Mexico
- Postgraduate School in Marine Sciences and Limnology, National Autonomous University of Mexico, University City, Exterior Circuit S/N, 04510, Coyoacan, Mexico City, Mexico
| | - Javier Carmona-Jiménez
- Ecology and Natural Resources Department, Science Faculty, National Autonomous University of Mexico, University City, Exterior Circuit S/N, 04510, Coyoacan, Mexico City, Mexico.
| | - Itzel Becerra-Absalón
- Comparative Biology Department, Science Faculty, National Autonomous University of Mexico, University City, Exterior Circuit S/N, 04510, Coyoacan, Mexico City, Mexico
| | - Elvira Perona
- Biology Department, Science Faculty, Autonomous University of Madrid, Darwin 2, Canto Blanco Campus, 28049, Madrid, Spain
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Archana CA, Sekar YS, Suresh KP, Subramaniam S, Sagar N, Rani S, Anandakumar J, Pandey RK, Barman NN, Patil SS. Investigating the Influence of ANTXR2 Gene Mutations on Protective Antigen Binding for Heightened Anthrax Resistance. Genes (Basel) 2024; 15:426. [PMID: 38674361 PMCID: PMC11049084 DOI: 10.3390/genes15040426] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 03/14/2024] [Accepted: 03/18/2024] [Indexed: 04/28/2024] Open
Abstract
Bacillus anthracis is the bacterium responsible for causing the zoonotic disease called anthrax. The disease presents itself in different forms like gastrointestinal, inhalation, and cutaneous. Bacterial spores are tremendously adaptable, can persist for extended periods and occasionally endanger human health. The Anthrax Toxin Receptor-2 (ANTXR2) gene acts as membrane receptor and facilitates the entry of the anthrax toxin into host cells. Additionally, mutations in the ANTXR2 gene have been linked to various autoimmune diseases, including Hyaline Fibromatosis Syndrome (HFS), Ankylosing Spondylitis (AS), Juvenile Hyaline Fibromatosis (JHF), and Infantile Systemic Hyalinosis (ISH). This study delves into the genetic landscape of ANTXR2, aiming to comprehend its associations with diverse disorders, elucidate the impacts of its mutations, and pinpoint minimal non-pathogenic mutations capable of reducing the binding affinity of the ANTXR2 gene with the protective antigen. Recognizing the pivotal role of single-nucleotide polymorphisms (SNPs) in shaping genetic diversity, we conducted computational analyses to discern highly deleterious and tolerated non-synonymous SNPs (nsSNPs) in the ANTXR2 gene. The Mutpred2 server determined that the Arg465Trp alteration in the ANTXR2 gene leads to altered DNA binding (p = 0.22) with a probability of a deleterious mutation of 0.808; notably, among the identified deleterious SNPs, rs368288611 (Arg465Trp) stands out due to its significant impact on altering the DNA-binding ability of ANTXR2. We propose these SNPs as potential candidates for hypertension linked to the ANTXR2 gene, which is implicated in blood pressure regulation. Noteworthy among the tolerated substitutions is rs200536829 (Ala33Ser), recognized as less pathogenic; this highlights its potential as a valuable biomarker, potentially reducing side effects on the host while also reducing binding with the protective antigen protein. Investigating these SNPs holds the potential to correlate with several autoimmune disorders and mitigate the impact of anthrax disease in humans.
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Affiliation(s)
- Chamalapura Ashwathama Archana
- ICAR-National Institute of Veterinary Epidemiology and Disease Informatics (NIVEDI), Bengaluru 560064, India; (C.A.A.); (Y.S.S.); (N.S.); (S.R.); (J.A.); (S.S.P.)
| | - Yamini Sri Sekar
- ICAR-National Institute of Veterinary Epidemiology and Disease Informatics (NIVEDI), Bengaluru 560064, India; (C.A.A.); (Y.S.S.); (N.S.); (S.R.); (J.A.); (S.S.P.)
| | - Kuralayanapalya Puttahonnappa Suresh
- ICAR-National Institute of Veterinary Epidemiology and Disease Informatics (NIVEDI), Bengaluru 560064, India; (C.A.A.); (Y.S.S.); (N.S.); (S.R.); (J.A.); (S.S.P.)
| | | | - Ningegowda Sagar
- ICAR-National Institute of Veterinary Epidemiology and Disease Informatics (NIVEDI), Bengaluru 560064, India; (C.A.A.); (Y.S.S.); (N.S.); (S.R.); (J.A.); (S.S.P.)
| | - Swati Rani
- ICAR-National Institute of Veterinary Epidemiology and Disease Informatics (NIVEDI), Bengaluru 560064, India; (C.A.A.); (Y.S.S.); (N.S.); (S.R.); (J.A.); (S.S.P.)
| | - Jayashree Anandakumar
- ICAR-National Institute of Veterinary Epidemiology and Disease Informatics (NIVEDI), Bengaluru 560064, India; (C.A.A.); (Y.S.S.); (N.S.); (S.R.); (J.A.); (S.S.P.)
| | - Rajan Kumar Pandey
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, 17177 Solna, Sweden;
| | - Nagendra Nath Barman
- College of Veterinary Science, Assam Agricultural University (AAU), Guwahati 781022, India;
| | - Sharanagouda S. Patil
- ICAR-National Institute of Veterinary Epidemiology and Disease Informatics (NIVEDI), Bengaluru 560064, India; (C.A.A.); (Y.S.S.); (N.S.); (S.R.); (J.A.); (S.S.P.)
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17
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Lv W, Lu X, Zhuge B, Zong H. Gene Editing of Candida glycerinogenes by Designed Toxin-Antitoxin Cassette. ACS Synth Biol 2024; 13:816-824. [PMID: 38365187 DOI: 10.1021/acssynbio.3c00640] [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] [Indexed: 02/18/2024]
Abstract
Candida glycerinogenes is an industrial yeast with excellent multistress resistance. However, due to the diploid genome and the lack of meiosis and screening markers, its molecular genetic operation is limited. Here, a gene editing system using the toxin-antitoxin pair relBE from the type II toxin-antitoxin system in Escherichia coli as a screening marker was constructed. The RelBE complex can specifically and effectively regulate cell growth and arrest through a conditionally controlled toxin RelE switch, thereby achieving the selection of positive recombinants. The constructed editing system achieved precise gene deletion, replacement, insertion, and gene episomal expression in C. glycerinogenes. Compared with the traditional amino acid deficiency complementation editing system, this editing system produced higher biomass and the gene deletion efficiency was increased by 3.5 times. Using this system, the production of 2-phenylethanol by C. glycerinogenes was increased by 11.5-13.5% through metabolic engineering and tolerance engineering strategies. These results suggest that the stable gene editing system based on toxin-antitoxin pairs can be used for gene editing of C. glycerinogenes to modify metabolic pathways and promote industrial applications. Therefore, the constructed gene editing system is expected to provide a promising strategy for polyploid industrial microorganisms lacking gene manipulation methods.
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Affiliation(s)
- Wen Lv
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- Lab of Industrial Microorganism & Research and Design Center for Polyols, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Xinyao Lu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- Lab of Industrial Microorganism & Research and Design Center for Polyols, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Bin Zhuge
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- Lab of Industrial Microorganism & Research and Design Center for Polyols, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Hong Zong
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
- Lab of Industrial Microorganism & Research and Design Center for Polyols, School of Biotechnology, Jiangnan University, Wuxi 214122, China
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18
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Warren Norris MAH, Plaskon DM, Tamayo R. Phase Variation of Flagella and Toxins in Clostridioides difficile is Mediated by Selective Rho-dependent Termination. J Mol Biol 2024; 436:168456. [PMID: 38278436 PMCID: PMC10942720 DOI: 10.1016/j.jmb.2024.168456] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 01/16/2024] [Accepted: 01/20/2024] [Indexed: 01/28/2024]
Abstract
Clostridioides difficile is an intestinal pathogen that exhibits phase variation of flagella and toxins through inversion of the flagellar (flg) switch controlling flagellar and toxin gene expression. The transcription termination factor Rho preferentially inhibits swimming motility of bacteria with the 'flg-OFF' switch sequence. How C. difficile Rho mediates this selectivity was unknown. C. difficile Rho contains an N-terminal insertion domain (NID) which is found in a subset of Rho orthologues and confers diverse functions. Here we determined how Rho distinguishes between flg-ON and -OFF mRNAs and the roles of the NID and other domains of C. difficile Rho. Using in vitro ATPase assays, we determined that Rho specifically binds a region containing the left inverted repeat of the flg switch, but only of flg-OFF mRNA, indicating that differential termination is mediated by selective Rho binding. Using a suite of in vivo and in vitro assays in C. difficile, we determined that the NID is essential for Rho termination of flg-OFF mRNA, likely by influencing the ability to form stable hexamers, and the RNA binding domain is critical for flg-OFF specific termination. This work gives insight into the novel mechanism by which Rho interacts with flg mRNA to mediate phase variation of flagella and toxins in C. difficile and broadens our understanding of Rho-mediated termination in an organism with an AT-rich genome.
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Affiliation(s)
- Mercedes A H Warren Norris
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - Dylan M Plaskon
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - Rita Tamayo
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA.
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19
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Paparella AS, Brew I, Hong HA, Ferriera W, Cutting S, Lamiable-Oulaidi F, Popadynec M, Tyler PC, Schramm VL. Isofagomine Inhibits Multiple TcdB Variants and Protects Mice from Clostridioides difficile-Induced Mortality. ACS Infect Dis 2024; 10:928-937. [PMID: 38334357 DOI: 10.1021/acsinfecdis.3c00507] [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] [Indexed: 02/10/2024]
Abstract
Clostridioides difficile causes life-threatening diarrhea and is one of the leading causes of nosocomial infections. During infection, C. difficile releases two gut-damaging toxins, TcdA and TcdB, which are the primary determinants of disease pathogenesis and are important therapeutic targets. Once in the cytosol of mammalian cells, TcdA and TcdB use UDP-glucose to glucosylate host Rho GTPases, which leads to cytoskeletal changes that result in a loss of intestinal integrity. Isofagomine inhibits TcdA and TcdB as a mimic of the glucocation transition state of the glucosyltransferase reaction. However, sequence variants of TcdA and TcdB across the clades of infective C. difficile continue to be identified, and therefore, evaluation of isofagomine inhibition against multiple toxin variants is required. Here, we show that isofagomine inhibits the glucosyltransferase domain of multiple TcdB variants and protects TcdB-induced cell rounding of the most common full-length toxin variants. Furthermore, we demonstrate that isofagomine protects against C. difficile-induced mortality in two murine models of C. difficile infection. Isofagomine treatment of mouse C. difficile infection also permitted the recovery of the gastrointestinal microbiota, an important barrier to preventing recurring C. difficile infection. The broad specificity of isofagomine supports its potential as a prophylactic to protect against C. difficile-induced morbidity and mortality.
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Affiliation(s)
- Ashleigh S Paparella
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York 10461, United States
| | - Isabella Brew
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York 10461, United States
| | - Huynh A Hong
- SporeGen Ltd., The London BioScience Innovation Centre, London NW1 0NH, U.K
| | - William Ferriera
- SporeGen Ltd., The London BioScience Innovation Centre, London NW1 0NH, U.K
| | - Simon Cutting
- SporeGen Ltd., The London BioScience Innovation Centre, London NW1 0NH, U.K
| | - Farah Lamiable-Oulaidi
- The Ferrier Research Institute, Victoria University of Wellington, Lower Hutt 5010, New Zealand
| | - Michael Popadynec
- The Ferrier Research Institute, Victoria University of Wellington, Lower Hutt 5010, New Zealand
| | - Peter C Tyler
- The Ferrier Research Institute, Victoria University of Wellington, Lower Hutt 5010, New Zealand
| | - Vern L Schramm
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York 10461, United States
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20
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Le LHM, Elgamoudi B, Colon N, Cramond A, Poly F, Ying L, Korolik V, Ferrero RL. Campylobacter jejuni extracellular vesicles harboring cytolethal distending toxin bind host cell glycans and induce cell cycle arrest in host cells. Microbiol Spectr 2024; 12:e0323223. [PMID: 38319111 PMCID: PMC10913475 DOI: 10.1128/spectrum.03232-23] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 12/20/2023] [Indexed: 02/07/2024] Open
Abstract
Cytolethal distending toxins (CDTs) are released by Gram-negative pathogens into the extracellular medium as free toxin or associated with extracellular vesicles (EVs), commonly known as outer membrane vesicles (OMVs). CDT production by the gastrointestinal pathogen Campylobacter jejuni has been implicated in colorectal tumorigenesis. Despite CDT being a major virulence factor for C. jejuni, little is known about the EV-associated form of this toxin. To address this point, C. jejuni mutants lacking each of the three CDT subunits (A, B, and C) were generated. C. jejuni cdtA, cdtB, and cdtC bacteria released EVs in similar numbers and sizes to wild-type bacteria, ranging from 5 to 530 nm (mean ± SEM = 118 ±6.9 nm). As the CdtAC subunits mediate toxin binding to host cells, we performed "surface shearing" experiments, in which EVs were treated with proteinase K and incubated with host cells. These experiments indicated that CDT subunits are internal to EVs and that surface proteins are probably not involved in EV-host cell interactions. Furthermore, glycan array studies demonstrated that EVs bind complex host cell glycans and share receptor binding specificities with C. jejuni bacteria for fucosyl GM1 ganglioside, P1 blood group antigen, sialyl, and sulfated Lewisx. Finally, we show that EVs from C. jejuni WT but not mutant bacteria induce cell cycle arrest in epithelial cells. In conclusion, we propose that EVs are an important mechanism for CDT release by C. jejuni and are likely to play a significant role in toxin delivery to host cells. IMPORTANCE Campylobacter jejuni is the leading cause of foodborne gastroenteritis in humans worldwide and a significant cause of childhood mortality due to diarrheal disease in developing countries. A major factor by which C. jejuni causes disease is a toxin, called cytolethal distending toxin (CDT). The biology of this toxin, however, is poorly understood. In this study, we report that C. jejuni CDT is protected within membrane blebs, known as extracellular vesicles (EVs), released by the bacterium. We showed that proteins on the surfaces of EVs are not required for EV uptake by host cells. Furthermore, we identified several sugar receptors that may be required for EV binding to host cells. By studying the EV-associated form of C. jejuni CDT, we will gain a greater understanding of how C. jejuni intoxicates host cells and how EV-associated CDT may be used in various therapeutic applications, including as anti-tumor therapies.
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Affiliation(s)
- Lena Hoang My Le
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Victoria, Australia
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Victoria, Australia
| | - Bassam Elgamoudi
- Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia
| | - Nina Colon
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Victoria, Australia
| | - Angus Cramond
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Victoria, Australia
| | - Frederic Poly
- Enteric Diseases Department, Naval Medical Research Centre, Silver Spring, Maryland, USA
| | - Le Ying
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Victoria, Australia
- Department of Molecular and Translational Sciences, Monash University, Victoria, Australia
| | - Victoria Korolik
- Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia
| | - Richard L. Ferrero
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Victoria, Australia
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Victoria, Australia
- Department of Molecular and Translational Sciences, Monash University, Victoria, Australia
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21
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Gong JJ, Huang IH, Su MSW, Xie SX, Liu WY, Huang CR, Hung YP, Wu SR, Tsai PJ, Ko WC, Chen JW. Phage transcriptional regulator X (PtrX)-mediated augmentation of toxin production and virulence in Clostridioides difficile strain R20291. Microbiol Res 2024; 280:127576. [PMID: 38183754 DOI: 10.1016/j.micres.2023.127576] [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: 10/03/2023] [Revised: 11/24/2023] [Accepted: 12/13/2023] [Indexed: 01/08/2024]
Abstract
Clostridioides difficile is a Gram-positive, anaerobic, and spore-forming bacterial member of the human gut microbiome. The primary virulence factors of C. difficile are toxin A and toxin B. These toxins damage the cell cytoskeleton and cause various diseases, from diarrhea to severe pseudomembranous colitis. Evidence suggests that bacteriophages can regulate the expression of the pathogenicity locus (PaLoc) genes of C. difficile. We previously demonstrated that the genome of the C. difficile RT027 strain NCKUH-21 contains a prophage-like DNA sequence, which was found to be markedly similar to that of the φCD38-2 phage. In the present study, we investigated the mechanisms underlying the φNCKUH-21-mediated regulation of the pathogenicity and the PaLoc genes expression in the lysogenized C. difficile strain R20291. The carriage of φNCKUH-21 in R20291 cells substantially enhanced toxin production, bacterial motility, biofilm formation, and spore germination in vitro. Subsequent mouse studies revealed that the lysogenized R20291 strain caused a more severe infection than the wild-type strain. We screened three φNCKUH-21 genes encoding DNA-binding proteins to check their effects on PaLoc genes expression. The overexpression of NCKUH-21_03890, annotated as a transcriptional regulator (phage transcriptional regulator X, PtrX), considerably enhanced toxin production, biofilm formation, and bacterial motility of R20291. Transcriptome analysis further confirmed that the overexpression of ptrX led to the upregulation of the expression of toxin genes, flagellar genes, and csrA. In the ptrX-overexpressing R20291 strain, PtrX influenced the expression of flagellar genes and the sigma factor gene sigD, possibly through an increased flagellar phase ON configuration ratio.
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Affiliation(s)
- Jun-Jia Gong
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - I-Hsiu Huang
- Department of Biochemistry and Microbiology, Oklahoma State University Center for Health Sciences, Tulsa, OK 74107, USA
| | - Marcia Shu-Wei Su
- Department of Biotechnology and Laboratory Science in Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Si-Xuan Xie
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Wei-Yong Liu
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Cheng-Rung Huang
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Yuan-Pin Hung
- Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Shang-Rung Wu
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Institute of Oral Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Pei-Jane Tsai
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Medical Laboratory Science and Biotechnology, National Cheng Kung University, Tainan, Taiwan; Department of Pathology, National Cheng Kung University Hospital, Tainan, Taiwan; Center for Clinical Medicine Research, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Wen-Chien Ko
- Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Jenn-Wei Chen
- Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
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22
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Girardin Y, Galle M, Vanden Abeele Y, De Greve H, Loris R. Evaluation of different strategies to produce Vibrio cholerae ParE2 toxin. Protein Expr Purif 2024; 215:106403. [PMID: 37977515 DOI: 10.1016/j.pep.2023.106403] [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: 10/12/2023] [Revised: 11/08/2023] [Accepted: 11/12/2023] [Indexed: 11/19/2023]
Abstract
Toxin-antitoxin (TA) systems are small operons that are omnipresent in bacteria and archaea with suggested roles in stabilization of mobile genetic elements, bacteriophage protection, stress response and possibly persister formation. A major bottleneck in the study of TA toxins is the production of sufficient amounts of well-folded, functional protein. Here we examine alternative approaches for obtaining the VcParE2 toxin from Vibrio cholerae. VcParE2 can be successfully produced via bacterial expression in presence of its cognate antitoxin VcParD2, followed by on-column unfolding and refolding. Alternatively, the toxin can be expressed in Spodoptera frugiperda (Sf9) insect cells. The latter requires disruption of the VcparE2 gene via introduction of an insect cell intron. Both methods provide protein with similar structural and functional characteristics.
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Affiliation(s)
- Yana Girardin
- Molecular Recognition Unit, Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium; Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Pleinlaan 2, 1050, Brussels, Belgium
| | - Margot Galle
- Molecular Recognition Unit, Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium; Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Pleinlaan 2, 1050, Brussels, Belgium
| | - Yaël Vanden Abeele
- Molecular Recognition Unit, Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium
| | - Henri De Greve
- Molecular Recognition Unit, Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium
| | - Remy Loris
- Molecular Recognition Unit, Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium; Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Pleinlaan 2, 1050, Brussels, Belgium.
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23
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Liu L, Zhuang H, Wang Y, Tu Y, Yu Y, Chen Y, Wu X. β-Hemolysin, not agrA mutation, inhibits the hemolysis of α-hemolysin in Staphylococcus aureus laboratory and clinical strains. mSphere 2024; 9:e0067323. [PMID: 38289073 PMCID: PMC10900901 DOI: 10.1128/msphere.00673-23] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 12/20/2023] [Indexed: 02/29/2024] Open
Abstract
Staphylococcus aureus produces various hemolysins regulated by the Agr-QS system, except β-hemolysin encoded by the gene hlb. A classical laboratory S. aureus strain RN4220 displays only the β-hemolysin phenotype. It was suspected that the 8A mutation at the end of its agrA gene delayed the expressions of hla and RNAIII, then failed to express α- and δ-hemolysins. However, hla gene expression was detected at the later culture time without α-hemolysin phenotype, the reason for such a phenotype has not been clearly understood. We created hlb knockout and complementary mutants via homologous recombination in RN4220 and NRS049, two strains that normally produce β-hemolysin and carry agrA mutation. We found interestingly that the presence or absence of α-hemolysin phenotype in such strains depended on the expression of β-hemolysin instead of agrA mutations, which only inhibited δ-hemolysin expression. The hemolysis phenotype was verified by the Christie-Atkinson-Munch-Peterson (CAMP) test. Quantitative reverse transcription PCR was carried out to evaluate the relative gene expressions of hlb, hla, and RNAIII. The construction of mutants did not affect the agrA mutation status. We demonstrate that the absence of α-hemolysin in S. aureus RN4220 and NRS049 strains is attributed to their production of β-hemolysin instead of agrA mutation. Our findings broaden the understanding of the molecular mechanisms that control hemolysin expression in S. aureus that is crucial for the development of new therapeutic strategies to combat S. aureus infections. IMPORTANCE α-Hemolysin is a critical virulence factor in Staphylococcus aureus and its expression is largely controlled by the Agr-QS system. Nonetheless, the hemolysis phenotype and the regulation of the Agr-QS system in S. aureus still hold many mysteries. Our study finds that it is the expression of β- hemolysin rather than the agrA mutation that inhibits the function of the α-hemolysin in an important S. aureus strain RN4220 and a clinical strain presents a similar phenotype, which clarifies the misunderstood hemolytic phenotype and mechanism of S. aureus. Our findings highlight the interactions among different toxins and their biological roles, combined with QS system regulation, which is ultimately the true underlying cause of its virulence. This emphasizes the importance of considering the collaborative action of various factors in the infection process caused by this significant human pathogen.
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Affiliation(s)
- Lin Liu
- Department of Infectious Disease, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Laboratory Medicine Center, Department of Clinical Laboratory, Zhejiang Provincial People’s Hospital, Affiliated People’s Hospital, Hangzhou Medical College, Hangzhou, Zhejiang, China
| | - Hemu Zhuang
- Department of Infectious Disease, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, Zhejiang, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
- Department of Respiratory and Critical Medicine, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Yanfei Wang
- Department of Infectious Disease, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, Zhejiang, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Yuexing Tu
- Laboratory Medicine Center, Department of Clinical Laboratory, Zhejiang Provincial People’s Hospital, Affiliated People’s Hospital, Hangzhou Medical College, Hangzhou, Zhejiang, China
- Department of Critical Care Medicine, Tongde Hospital of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Yunsong Yu
- Department of Infectious Disease, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, Zhejiang, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Yan Chen
- Department of Infectious Disease, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, Zhejiang, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Xueqing Wu
- Department of Infectious Disease, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, Zhejiang, China
- Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
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24
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Fraikin N, Van Melderen L. Single-cell evidence for plasmid addiction mediated by toxin-antitoxin systems. Nucleic Acids Res 2024; 52:1847-1859. [PMID: 38224456 PMCID: PMC10899753 DOI: 10.1093/nar/gkae018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 12/22/2023] [Accepted: 01/03/2024] [Indexed: 01/16/2024] Open
Abstract
Toxin-antitoxin (TA) systems are small selfish genetic modules that increase vertical stability of their replicons. They have long been thought to stabilize plasmids by killing cells that fail to inherit a plasmid copy through a phenomenon called post-segregational killing (PSK) or addiction. While this model has been widely accepted, no direct observation of PSK was reported in the literature. Here, we devised a system that enables visualization of plasmid loss and PSK at the single-cell level using meganuclease-driven plasmid curing. Using the ccd system, we show that cells deprived of a ccd-encoding plasmid show hallmarks of DNA damage, i.e. filamentation and induction of the SOS response. Activation of ccd triggered cell death in most plasmid-free segregants, although some intoxicated cells were able to resume growth, showing that PSK-induced damage can be repaired in a SOS-dependent manner. Damage induced by ccd activates resident lambdoid prophages, which potentiate the killing effect of ccd. The loss of a model plasmid containing TA systems encoding toxins presenting various molecular mechanisms induced different morphological changes, growth arrest and loss of viability. Our experimental setup enables further studies of TA-induced phenotypes and suggests that PSK is a general mechanism for plasmid stabilization by TA systems.
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Affiliation(s)
- Nathan Fraikin
- Bacterial Genetics and Physiology, Department of Molecular Biology, Faculté des Sciences, Université Libre de Bruxelles (ULB), 6041 Gosselies, Belgium
| | - Laurence Van Melderen
- Bacterial Genetics and Physiology, Department of Molecular Biology, Faculté des Sciences, Université Libre de Bruxelles (ULB), 6041 Gosselies, Belgium
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25
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Bachmann I, Behrmann O, Klingenberg-Ernst M, Rupnik M, Hufert FT, Dame G, Weidmann M. Rapid Isothermal Detection of Pathogenic Clostridioides difficile Using Recombinase Polymerase Amplification. Anal Chem 2024; 96:3267-3275. [PMID: 38358754 DOI: 10.1021/acs.analchem.3c02985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2024]
Abstract
Nosocomial-associated diarrhea due to Clostridioides difficile infection (CDI) is diagnosed after sample precultivation by the detection of the toxins in enzyme immunoassays or via toxin gene nucleic acid amplification. Rapid and direct diagnosis is important for targeted treatment to prevent severe cases and recurrence. We developed two singleplex and a one-pot duplex fluorescent 15 min isothermal recombinase polymerase amplification (RPA) assays targeting the toxin genes A and B (tcdA and tcdB). Furthermore, we adapted the singleplex RPA to a 3D-printed microreactor device. Analytical sensitivity was determined using a DNA standard and DNA extracts of 20 C. difficile strains with different toxinotypes. Nineteen clostridial and gastrointestinal bacteria strains were used to determine analytical specificity. Adaptation of singleplex assays to duplex assays in a 50 μL volume required optimized primer and probe concentrations. A volume reduction by one-fourth (12.4 μL) was established for the 3D-printed microreactor. Mixing of RPA was confirmed as essential for optimal analytical sensitivity. Detection limits (LOD) ranging from 119 to 1411 DNA molecules detected were similar in the duplex tube format and in the singleplex 3D-printed microreactor format. The duplex RPA allows the simultaneous detection of both toxins important for the timely and reliable diagnosis of CDI. The 3D-printed reaction chamber can be developed into a microfluidic lab-on-a-chip system use at the point of care.
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Affiliation(s)
- Iris Bachmann
- Institute of Microbiology and Virology, Brandenburg Medical School Theodor Fontane, Universitätsplatz 1, 01968 Senftenberg, Germany
| | - Ole Behrmann
- Institute of Microbiology and Virology, Brandenburg Medical School Theodor Fontane, Universitätsplatz 1, 01968 Senftenberg, Germany
| | | | - Maja Rupnik
- Center for Medical Microbiology, Department for Microbiological Research, National Laboratory for Health, Environment and Food, Prvomajska ulica 1, 2000 Maribor, Slovenia
- Faculty of Medicine, Maribor, University of Maribor, Taborska ulica 8, 2000 Maribor, Slovenia
| | - Frank T Hufert
- Institute of Microbiology and Virology, Brandenburg Medical School Theodor Fontane, Universitätsplatz 1, 01968 Senftenberg, Germany
- Department of Virology, University Medical Center, Kreuzbergring 57, 37075 Göttingen, Germany
- Brandenburg University of Technology Cottbus - Senftenberg, Universitätsplatz 1, 01968 Senftenberg, Germany
- Faculty of Health Sciences, Joint Faculty of the Brandenburg University of Technology Cottbus - Senftenberg, the Brandenburg Medical School Theodor Fontane and the University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
| | - Gregory Dame
- Institute of Microbiology and Virology, Brandenburg Medical School Theodor Fontane, Universitätsplatz 1, 01968 Senftenberg, Germany
- Faculty of Health Sciences, Joint Faculty of the Brandenburg University of Technology Cottbus - Senftenberg, the Brandenburg Medical School Theodor Fontane and the University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
| | - Manfred Weidmann
- Institute of Microbiology and Virology, Brandenburg Medical School Theodor Fontane, Universitätsplatz 1, 01968 Senftenberg, Germany
- Department of Virology, University Medical Center, Kreuzbergring 57, 37075 Göttingen, Germany
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26
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Ghosh S, Erickson D, Chua MJ, Collins J, Jala VR. The microbial metabolite urolithin A reduces Clostridioides difficile toxin expression and toxin-induced epithelial damage. mSystems 2024; 9:e0125523. [PMID: 38193707 PMCID: PMC10878087 DOI: 10.1128/msystems.01255-23] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Accepted: 12/04/2023] [Indexed: 01/10/2024] Open
Abstract
Clostridioides difficile is a Gram-positive, anaerobic, spore-forming bacterium responsible for antibiotic-associated pseudomembranous colitis. Clostridioides difficile infection (CDI) symptoms can range from diarrhea to life-threatening colon damage. Toxins produced by C. difficile (TcdA and TcdB) cause intestinal epithelial injury and lead to severe gut barrier dysfunction, stem cell damage, and impaired regeneration of the gut epithelium. Current treatment options for intestinal repair are limited. In this study, we demonstrate that treatment with the microbial metabolite urolithin A (UroA) attenuates CDI-induced adverse effects on the colon epithelium in a preclinical model of CDI-induced colitis. Moreover, our analysis suggests that UroA treatment protects against C. difficile-induced inflammation, disruption of gut barrier integrity, and intestinal tight junction proteins in the colon of CDI mice. Importantly, UroA treatment significantly reduced the expression and release of toxins from C. difficile without inducing bacterial cell death. These results indicate the direct regulatory effects of UroA on bacterial gene regulation. Overall, our findings reveal a novel aspect of UroA activity, as it appears to act at both the bacterial and host levels to protect against CDI-induced colitis pathogenesis. This research sheds light on a promising avenue for the development of novel treatments for C. difficile infection.IMPORTANCETherapy for Clostridioides difficile infections includes the use of antibiotics, immunosuppressors, and fecal microbiota transplantation. However, these treatments have several drawbacks, including the loss of colonization resistance, the promotion of autoimmune disorders, and the potential for unknown pathogens in donor samples. To date, the potential benefits of microbial metabolites in CDI-induced colitis have not been fully investigated. Here, we report for the first time that the microbial metabolite urolithin A has the potential to block toxin production from C. difficile and enhance gut barrier function to mitigate CDI-induced colitis.
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Affiliation(s)
- Sweta Ghosh
- Department of Microbiology and Immunology, University of Louisville, Louisville, Kentucky, USA
- UofL-Brown Cancer Center, Louisville, Kentucky, USA
| | - Daniel Erickson
- Department of Microbiology and Immunology, University of Louisville, Louisville, Kentucky, USA
| | - Michelle J. Chua
- Department of Microbiology and Immunology, University of Louisville, Louisville, Kentucky, USA
| | - James Collins
- Department of Microbiology and Immunology, University of Louisville, Louisville, Kentucky, USA
- Center for Predictive Medicine, University of Louisville, Louisville, Kentucky, USA
- Center for Microbiomics, Inflammation and Pathogenicity, University of Louisville, Louisville, Kentucky, USA
| | - Venkatakrishna Rao Jala
- Department of Microbiology and Immunology, University of Louisville, Louisville, Kentucky, USA
- UofL-Brown Cancer Center, Louisville, Kentucky, USA
- Center for Microbiomics, Inflammation and Pathogenicity, University of Louisville, Louisville, Kentucky, USA
- Center for Integrative Environmental Health Sciences, University of Louisville, Louisville, Kentucky, USA
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Perri KA, Bellinger BJ, Ashworth MP, Manning SR. Environmental Factors Impacting the Development of Toxic Cyanobacterial Proliferations in a Central Texas Reservoir. Toxins (Basel) 2024; 16:91. [PMID: 38393169 PMCID: PMC10892464 DOI: 10.3390/toxins16020091] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 01/24/2024] [Accepted: 01/30/2024] [Indexed: 02/25/2024] Open
Abstract
Cyanobacterial harmful algal proliferations (cyanoHAPs) are increasingly associated with dog and livestock deaths when benthic mats break free of their substrate and float to the surface. Fatalities have been linked to neurotoxicosis from anatoxins, potent alkaloids produced by certain genera of filamentous cyanobacteria. After numerous reports of dog illnesses and deaths at a popular recreation site on Lady Bird Lake, Austin, Texas in late summer 2019, water and floating mat samples were collected from several sites along the reservoir. Water quality parameters were measured and mat samples were maintained for algal isolation and DNA identification. Samples were also analyzed for cyanobacterial toxins using LC-MS. Dihydroanatoxin-a was detected in mat materials from two of the four sites (0.6-133 ng/g wet weight) while water samples remained toxin-free over the course of the sampling period; no other cyanobacterial toxins were detected. DNA sequencing analysis of cyanobacterial isolates yielded a total of 11 genera, including Geitlerinema, Tyconema, Pseudanabaena, and Phormidium/Microcoleus, taxa known to produce anatoxins, including dihydroanatoxin, among other cyanotoxins. Analyses indicate that low daily upriver dam discharge, higher TP and NO3 concentrations, and day of the year were the main parameters associated with the presence of toxic floating cyanobacterial mats.
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Affiliation(s)
- Katherine A. Perri
- Department of Biological Sciences, Institute of Environment, Biscayne Bay Campus, Florida International University, 3000 NE 151st St., North Miami, FL 33181, USA;
| | - Brent J. Bellinger
- Watershed Protection Department, City of Austin, 505 Barton Springs Road, 11th Floor, Austin, TX 78704, USA;
| | - Matt P. Ashworth
- UTEX Culture Collection of Algae, College of Natural Sciences, University of Texas, Austin 204 W 24th Street, Austin, TX 78701, USA;
| | - Schonna R. Manning
- Department of Biological Sciences, Institute of Environment, Biscayne Bay Campus, Florida International University, 3000 NE 151st St., North Miami, FL 33181, USA;
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Winter K, Houle S, Dozois CM, Ward BJ. Multimodal vaccination targeting the receptor binding domains of Clostridioides difficile toxins A and B with an attenuated Salmonella Typhimurium vector (YS1646) protects mice from lethal challenge. Microbiol Spectr 2024; 12:e0310922. [PMID: 38189293 PMCID: PMC10846063 DOI: 10.1128/spectrum.03109-22] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 12/06/2023] [Indexed: 01/09/2024] Open
Abstract
Developing a vaccine against Clostridioides difficile is a key strategy to protect the elderly. Two candidate vaccines using a traditional approach of intramuscular (IM) delivery of recombinant antigens targeting C. difficile toxins A (TcdA) and B (TcdB) failed to meet their primary endpoints in large phase 3 trials. To elicit a mucosal response against C. difficile, we repurposed an attenuated strain of Salmonella Typhimurium (YS1646) to deliver the receptor binding domains (rbd) of TcdA and TcdB to the gut-associated lymphoid tissues, to elicit a mucosal response against C. difficile. In this study, YS1646 candidates with either rbdA or rbdB expression cassettes integrated into the bacterial chromosome at the attTn7 site were generated and used in a short-course multimodal vaccination strategy that combined oral delivery of the YS1646 candidate(s) on days 0, 2, and 4 and IM delivery of recombinant antigen(s) on day 0. Five weeks after vaccination, mice had high serum IgG titers and increased intestinal antigen-specific IgA titers. Multimodal vaccination increased the IgG avidity compared to the IM-only control. In the mesenteric lymph nodes, we observed increased IL-5 secretion and increased IgA+ plasma cells. Oral vaccination skewed the IgG response toward IgG2c dominance (vs IgG1 dominance in the IM-only group). Both oral alone and multimodal vaccination against TcdA protected mice from lethal C. difficile challenge (100% survival vs 30% in controls). Given the established safety profile of YS1646, we hope to move this vaccine candidate forward into a phase I clinical trial.IMPORTANCEClostridioides difficile remains a major public health threat, and new approaches are needed to develop an effective vaccine. To date, the industry has focused on intramuscular vaccination targeting the C. difficile toxins. Multiple disappointing results in phase III trials have largely confirmed that this may not be the best strategy. As C. difficile is a pathogen that remains in the intestine, we believe that targeting mucosal immune responses in the gut will be a more successful strategy. We have repurposed a highly attenuated Salmonella Typhimurium (YS1646), originally pursued as a cancer therapeutic, as a vaccine vector. Using a multimodal vaccination strategy (both recombinant protein delivered intramuscularly and YS1646 expressing antigen delivered orally), we elicited both systemic and local immune responses. Oral vaccination alone completely protected mice from lethal challenge. Given the established safety profile of YS1646, we hope to move these vaccine candidates forward into a phase I clinical trial.
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Affiliation(s)
- Kaitlin Winter
- Department of Microbiology and Immunology, McGill University, Montreal, Québec, Canada
- Research Institute of the McGill University Health Centre, Montreal, Québec, Canada
| | - Sébastien Houle
- Institut National de Recherche Scientifique–Centre Armand-Frappier Santé Biotechnologie, Laval, Québec, Canada
| | - Charles M. Dozois
- Institut National de Recherche Scientifique–Centre Armand-Frappier Santé Biotechnologie, Laval, Québec, Canada
| | - Brian J. Ward
- Department of Microbiology and Immunology, McGill University, Montreal, Québec, Canada
- Research Institute of the McGill University Health Centre, Montreal, Québec, Canada
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Jiang YN, Tamiya-Ishitsuka H, Aoi R, Okabe T, Yokota A, Noda N. MazEF Homologs in Symbiobacterium thermophilum Exhibit Cross-Neutralization with Non-Cognate MazEFs. Toxins (Basel) 2024; 16:81. [PMID: 38393159 PMCID: PMC10893535 DOI: 10.3390/toxins16020081] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 01/25/2024] [Accepted: 01/30/2024] [Indexed: 02/25/2024] Open
Abstract
Toxin-antitoxin systems are preserved by nearly every prokaryote. The type II toxin MazF acts as a sequence-specific endoribonuclease, cleaving ribonucleotides at specific sequences that vary from three to seven bases, as has been reported in different host organisms to date. The present study characterized the MazEF module (MazEF-sth) conserved in the Symbiobacterium thermophilum IAM14863 strain, a Gram-negative syntrophic bacterium that can be supported by co-culture with multiple bacteria, including Bacillus subtilis. Based on a method combining massive parallel sequencing and the fluorometric assay, MazF-sth was determined to cleave ribonucleotides at the UACAUA motif, which is markedly similar to the motifs recognized by MazF from B. subtilis (MazF-bs), and by several MazFs from Gram-positive bacteria. MazF-sth, with mutations at conserved amino acid residues Arg29 and Thr52, lost most ribonuclease activity, indicating that these residues that are crucial for MazF-bs also play significant roles in MazF-sth catalysis. Further, cross-neutralization between MazF-sth and the non-cognate MazE-bs was discovered, and herein, the neutralization mechanism is discussed based on a protein-structure simulation via AlphaFold2 and multiple sequence alignment. The conflict between the high homology shared by these MazF amino acid sequences and the few genetic correlations among their host organisms may provide evidence of horizontal gene transfer.
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Affiliation(s)
- Yu-Nong Jiang
- Master’s/Doctoral Program in Life Science Innovation, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba 305-8572, Ibaraki, Japan
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Ibaraki, Japan
| | - Hiroko Tamiya-Ishitsuka
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Ibaraki, Japan
| | - Rie Aoi
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Ibaraki, Japan
- Department of Life Science and Medical Bioscience, Waseda University, Shinjuku-ku 162-8480, Tokyo, Japan
| | - Takuma Okabe
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Ibaraki, Japan
- Department of Life Science and Medical Bioscience, Waseda University, Shinjuku-ku 162-8480, Tokyo, Japan
| | - Akiko Yokota
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Ibaraki, Japan
| | - Naohiro Noda
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Ibaraki, Japan
- Department of Life Science and Medical Bioscience, Waseda University, Shinjuku-ku 162-8480, Tokyo, Japan
- Master’s/Doctoral Program in Life Science Innovation, School of Integrative and Global Majors, University of Tsukuba, Tsukuba 305-8572, Ibaraki, Japan
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30
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Danov A, Segev O, Bograd A, Ben Eliyahu Y, Dotan N, Kaplan T, Levy A. Toxinome-the bacterial protein toxin database. mBio 2024; 15:e0191123. [PMID: 38117054 PMCID: PMC10790787 DOI: 10.1128/mbio.01911-23] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 11/14/2023] [Indexed: 12/21/2023] Open
Abstract
IMPORTANCE Microbes use protein toxins as important tools to attack neighboring cells, microbial or eukaryotic, and for self-killing when attacked by viruses. These toxins work through different mechanisms to inhibit cell growth or kill cells. Microbes also use antitoxin proteins to neutralize the toxin activities. Here, we developed a comprehensive database called Toxinome of nearly two million toxins and antitoxins that are encoded in 59,475 bacterial genomes. We described the distribution of bacterial toxins and identified that they are depleted by bacteria that live in hot and cold temperatures. We found 5,161 cases in which toxins and antitoxins are densely clustered in bacterial genomes and termed these areas "Toxin Islands." The Toxinome database is a useful resource for anyone interested in toxin biology and evolution, and it can guide the discovery of new toxins.
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Affiliation(s)
- Aleks Danov
- Department of Plant Pathology and Microbiology, Institute of Environmental Science, The Faculty of Agriculture, Food, and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Ofir Segev
- Department of Plant Pathology and Microbiology, Institute of Environmental Science, The Faculty of Agriculture, Food, and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Avi Bograd
- Department of Plant Pathology and Microbiology, Institute of Environmental Science, The Faculty of Agriculture, Food, and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Yedidya Ben Eliyahu
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Noam Dotan
- Department of Brain Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Tommy Kaplan
- School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel
- Department of Developmental Biology and Cancer Research, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Asaf Levy
- Department of Plant Pathology and Microbiology, Institute of Environmental Science, The Faculty of Agriculture, Food, and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
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31
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Singh A, Lankapalli AK, Mendem SK, Semmler T, Ahmed N. Unraveling the evolutionary dynamics of toxin-antitoxin systems in diverse genetic lineages of Escherichia coli including the high-risk clonal complexes. mBio 2024; 15:e0302323. [PMID: 38117088 PMCID: PMC10790755 DOI: 10.1128/mbio.03023-23] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 11/15/2023] [Indexed: 12/21/2023] Open
Abstract
IMPORTANCE Large-scale genomic studies of E. coli provide an invaluable opportunity to understand how genomic fine-tuning contributes to the transition of bacterial lifestyle from being commensals to mutualists or pathogens. Within this context, through machine learning-based studies, it appears that TA systems play an important role in the classification of high-risk clonal lineages and could be attributed to their epidemiological success. Due to these profound indications and assumptions, we attempted to provide unique insights into the ordered world of TA systems at the population level by investigating the diversity and evolutionary patterns of TA genes across 19 different STs of E. coli. Further in-depth analysis of ST-specific TA structures and associated genetic coordinates holds the potential to elucidate the functional implications of TA systems in bacterial cell survival and persistence, by and large.
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Affiliation(s)
- Anuradha Singh
- Pathogen Biology Laboratory, Department of Biotechnology and Bioinformatics, University of Hyderabad, Hyderabad, Telangana State, India
| | - Aditya Kumar Lankapalli
- Department of Biology and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, Oxford, United Kingdom
| | - Suresh Kumar Mendem
- Pathogen Biology Laboratory, Department of Biotechnology and Bioinformatics, University of Hyderabad, Hyderabad, Telangana State, India
| | | | - Niyaz Ahmed
- Pathogen Biology Laboratory, Department of Biotechnology and Bioinformatics, University of Hyderabad, Hyderabad, Telangana State, India
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Sapa D, Brosse A, Coullon H, Péan de Ponfilly G, Candela T, Le Monnier A. A Streamlined Method to Obtain Biologically Active TcdA and TcdB Toxins from Clostridioides difficile. Toxins (Basel) 2024; 16:38. [PMID: 38251254 PMCID: PMC10821508 DOI: 10.3390/toxins16010038] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 12/15/2023] [Accepted: 12/30/2023] [Indexed: 01/23/2024] Open
Abstract
The major virulence factors of Clostridioides difficile (C. difficile) are enterotoxins A (TcdA) and B (TcdB). The study of toxins is a crucial step in exploring the virulence of this pathogen. Currently, the toxin purification process is either laborious and time-consuming in C. difficile or performed in heterologous hosts. Therefore, we propose a streamlined method to obtain functional toxins in C. difficile. Two C. difficile strains were generated, each harboring a sequence encoding a His-tag at the 3' end of C. difficile 630∆erm tcdA or tcdB genes. Each toxin gene is expressed using the Ptet promoter, which is inducible by anhydro-tetracycline. The obtained purification yields were 0.28 mg and 0.1 mg per liter for rTcdA and rTcdB, respectively. In this study, we successfully developed a simple routine method that allows the production and purification of biologically active rTcdA and rTcdB toxins with similar activities compared to native toxins.
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Affiliation(s)
- Diane Sapa
- Micalis Institute, Université Paris-Saclay, INRAE, AgroParisTech, 78350 Jouy-en-Josas, France; (D.S.); (H.C.); (G.P.d.P.); (T.C.); (A.L.M.)
| | - Anaïs Brosse
- Micalis Institute, Université Paris-Saclay, INRAE, AgroParisTech, 78350 Jouy-en-Josas, France; (D.S.); (H.C.); (G.P.d.P.); (T.C.); (A.L.M.)
| | - Héloïse Coullon
- Micalis Institute, Université Paris-Saclay, INRAE, AgroParisTech, 78350 Jouy-en-Josas, France; (D.S.); (H.C.); (G.P.d.P.); (T.C.); (A.L.M.)
| | - Gauthier Péan de Ponfilly
- Micalis Institute, Université Paris-Saclay, INRAE, AgroParisTech, 78350 Jouy-en-Josas, France; (D.S.); (H.C.); (G.P.d.P.); (T.C.); (A.L.M.)
- Service de Microbiologie Clinique, GH Paris Saint-Joseph, 75674 Paris, France
| | - Thomas Candela
- Micalis Institute, Université Paris-Saclay, INRAE, AgroParisTech, 78350 Jouy-en-Josas, France; (D.S.); (H.C.); (G.P.d.P.); (T.C.); (A.L.M.)
| | - Alban Le Monnier
- Micalis Institute, Université Paris-Saclay, INRAE, AgroParisTech, 78350 Jouy-en-Josas, France; (D.S.); (H.C.); (G.P.d.P.); (T.C.); (A.L.M.)
- Service de Microbiologie Clinique, GH Paris Saint-Joseph, 75674 Paris, France
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Zarin S, Alam A, Hasnain SE, Ehtesham NZ. Are all VapC toxins of Mycobacterium tuberculosis endowed with enigmatic RNase activity? J Biosci 2024; 49:35. [PMID: 38384243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
Mycobacterium tuberculosis (M. tb) employs an extensive network of more than 90 toxin-antitoxin systems, and among them, VapC toxins are the most abundant. While most VapCs function as classical RNases with toxic effects, a significant number of them do not exhibit toxicity. However, these non-toxic VapCs may retain specific RNA binding abilities as seen in case of VapC16, leading to ribosome stalling at specific codons and reprofiling M. tb's proteome to aid in the bacterium's survival under different stressful conditions within the host. Here, we challenge the conventional classification of all VapC toxins as RNases and highlight the complexity of M. tb's strategies for survival and adaptation during infection.
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Affiliation(s)
- Sheeba Zarin
- Institute of Molecular Medicine, Jamia Hamdard, Hamdard Nagar, New Delhi 110 062, India
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Yang J, Wang X, Hu T, Huang H, Chen G, Jin B, Zeng G, Liu J. Entero-toxigenic Bacteroides fragilis contributes to intestinal barrier injury and colorectal cancer progression by mediating the BFT/STAT3/ZEB2 pathway. Cell Cycle 2024; 23:70-82. [PMID: 38273425 PMCID: PMC11005799 DOI: 10.1080/15384101.2024.2309005] [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: 06/27/2023] [Accepted: 12/21/2023] [Indexed: 01/27/2024] Open
Abstract
Our previous findings confirmed the high enrichment of Bacteroides fragilis (BF) in fecal samples from patients with colorectal cancer (CRC). The intestinal mucosal barrier is the first defense of the organism against commensal flora and intestinal pathogens and is closely associated with the occurrence and development of CRC. Therefore, this study aimed to investigate the molecular mechanisms through which BF mediates intestinal barrier injury and CRC progression. SW480 cells and a Caco2 intestinal barrier model were treated with entero-toxigenic BF (ETBF), its enterotoxin (B. fragilis toxin, BFT), and non-toxigenic BF (NTBF). Cell counting kit-8, flow cytometry, wound healing and transwell assays were performed to analyze the proliferation, apoptosis, migration, and invasion of SW480 cells. Transmission electron microscopy, FITC-dextran, and transepithelial electrical resistance (TEER) were used to analyze damage in the Caco2 intestinal barrier model. The Azoxymethane/Dextran Sulfate Sodium (AOM/DSS) animal model was established to evaluate the effect of ETBF on intestinal barrier injury and CRC progression in vivo. ETBF and BFT enhanced the viability, wound healing ratio, invasion, and EMT of SW480 cells. In addition, ETBF and BFT disrupted the tight junctions and villus structure in the intestinal barrier model, resulting in increased permeability and reduced TEER. Similarly, the expression of intestinal barrier-related proteins (MUC2, Occludin and Zo-1) was restricted by ETBF and BFT. Interestingly, the STAT3/ZEB2 axis was activated by ETBF and BFT, and treatment with Brevilin A (a STAT3 inhibitor) or knockdown of ZEB2 limited the promotional effect of ETBF and BFT on the SW480 malignant phenotype. In vivo experiments also confirmed that ETBF colonization accelerated tumor load, carcinogenesis, and intestinal mucosal barrier damage in the colorectum of the AOM/DSS animal model, and that treatment with Brevilin A alleviated these processes. ETBF-secreted BFT accelerated intestinal barrier damage and CRC by activating the STAT3/ZEB2 axis. Our findings provide new insights and perspectives for the application of ETBF in CRC treatment.
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Affiliation(s)
- Jian Yang
- Department of General Surgery, Chengdu Fifth People’s Hospital, Chengdu, Sichuan, China
- The Second Clinical Medical College, Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Chengdu Fifth People’s Hospital, Cancer Prevention and Treatment Institute of Chengdu, Chengdu, Sichuan, China
| | - Xue Wang
- Department of General Surgery, Chengdu Fifth People’s Hospital, Chengdu, Sichuan, China
- The Second Clinical Medical College, Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Chengdu Fifth People’s Hospital, Cancer Prevention and Treatment Institute of Chengdu, Chengdu, Sichuan, China
| | - Tao Hu
- Department of General Surgery, Chengdu Fifth People’s Hospital, Chengdu, Sichuan, China
- The Second Clinical Medical College, Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Chengdu Fifth People’s Hospital, Cancer Prevention and Treatment Institute of Chengdu, Chengdu, Sichuan, China
| | - He Huang
- Department of General Surgery, Chengdu Fifth People’s Hospital, Chengdu, Sichuan, China
- The Second Clinical Medical College, Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Chengdu Fifth People’s Hospital, Cancer Prevention and Treatment Institute of Chengdu, Chengdu, Sichuan, China
| | - Gang Chen
- Department of General Surgery, Chengdu Fifth People’s Hospital, Chengdu, Sichuan, China
- The Second Clinical Medical College, Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Chengdu Fifth People’s Hospital, Cancer Prevention and Treatment Institute of Chengdu, Chengdu, Sichuan, China
| | - Bo Jin
- Department of General Surgery, Chengdu Fifth People’s Hospital, Chengdu, Sichuan, China
- The Second Clinical Medical College, Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Chengdu Fifth People’s Hospital, Cancer Prevention and Treatment Institute of Chengdu, Chengdu, Sichuan, China
| | - Guilin Zeng
- The Second Clinical Medical College, Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Chengdu Fifth People’s Hospital, Cancer Prevention and Treatment Institute of Chengdu, Chengdu, Sichuan, China
- Department of Medical Oncology, Chengdu Fifth People’s Hospital, Chengdu, Sichuan, China
| | - Jian Liu
- Department of General Surgery, Chengdu Fifth People’s Hospital, Chengdu, Sichuan, China
- The Second Clinical Medical College, Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
- Chengdu Fifth People’s Hospital, Cancer Prevention and Treatment Institute of Chengdu, Chengdu, Sichuan, China
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35
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Etemad A, Kalani BS, Ghafourian S, Khodaei N, Davari M, Sadeghifard N. GNAT toxin may have a potential role in Pseudomonas aeruginosa persistence: an in vitro and in silico study. Future Microbiol 2024; 19:21-31. [PMID: 38294294 DOI: 10.2217/fmb-2023-0134] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2024] Open
Abstract
Aims: Persistent cells are primarily responsible for developing antibiotic resistance and the recurrence of Pseudomonas aeruginosa. This study investigated the possible role of GNAT toxin in persistence. Materials & methods: P. aeruginosa was exposed to five MIC concentrations of ciprofloxacin. The expression levels of target genes were assessed. The GNAT/HTH system was bioinformatically studied, and an inhibitory peptide was designed to disrupt this system. Results: Ciprofloxacin can induce bacterial persistence. There was a significant increase in the expression of the GNAT toxin during the persistence state. A structural study of the GNAT/HTH system determined that an inhibitory peptide could be designed to block this system effectively. Conclusion: The GNAT/HTH system shows promise as a novel therapeutic target for combating P. aeruginosa infections.
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Affiliation(s)
- Anahita Etemad
- Department of Microbiology, Faculty of Medicine, Ilam University of Medical Sciences, Ilam, Iran
| | - Behrooz Sadeghi Kalani
- Department of Microbiology, Faculty of Medicine, Ilam University of Medical Sciences, Ilam, Iran
- Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran
| | - Sobhan Ghafourian
- Department of Microbiology, Faculty of Medicine, Ilam University of Medical Sciences, Ilam, Iran
- Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran
| | - Niloofar Khodaei
- Department of Microbiology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Maryam Davari
- IT Unit of Medical School, Ilam University of Medical Sciences, Ilam, Iran
| | - Nourkhoda Sadeghifard
- Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran
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Hill CA, Casterline BW, Valguarnera E, Hecht AL, Shepherd ES, Sonnenburg JL, Bubeck Wardenburg J. Bacteroides fragilis toxin expression enables lamina propria niche acquisition in the developing mouse gut. Nat Microbiol 2024; 9:85-94. [PMID: 38168616 DOI: 10.1038/s41564-023-01559-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 11/14/2023] [Indexed: 01/05/2024]
Abstract
Bacterial toxins are well-studied virulence factors; however, recent studies have revealed their importance in bacterial niche adaptation. Enterotoxigenic Bacteroides fragilis (ETBF) expresses B. fragilis toxin (BFT) that we hypothesized may contribute to both colonic epithelial injury and niche acquisition. We developed a vertical transmission model for ETBF in mice that showed that BFT enabled ETBF to access a lamina propria (LP) niche during colonic microbiome development that was inaccessible to non-toxigenic B. fragilis. LP entry by ETBF required BFT metalloprotease activity, and showed temporal restriction to the pre-weaning period, dependent on goblet-cell-associated passages. In situ single-cell analysis showed bft expression at the apical epithelial surface and within the LP. BFT expression increased goblet cell number and goblet-cell-associated passage formation. These findings define a paradigm by which bacterial toxin expression specifies developmental niche acquisition, suggesting that a selective advantage conferred by a toxin may impact long-term host health.
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Affiliation(s)
- Craig A Hill
- Department of Pediatrics, Washington University, St. Louis, MO, USA
| | - Benjamin W Casterline
- Interdisciplinary Scientist Training Program, University of Chicago, Chicago, IL, USA
- Department of Dermatology, University of Missouri School of Medicine, Columbia, MO, USA
| | | | - Aaron L Hecht
- Interdisciplinary Scientist Training Program, University of Chicago, Chicago, IL, USA
- Division of Gastroenterology and Hepatology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | | | - Justin L Sonnenburg
- Department of Microbiology and Immunology, Stanford University, Palo Alto, CA, USA
- Chan Zuckerberg Biohub, San Francisco, CA, USA
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Nguyen MQ, Kim DH, Shim HJ, Ta HKK, Vu TL, Nguyen TKO, Lim JC, Choe H. Novel Anti-Mesothelin Nanobodies and Recombinant Immunotoxins with Pseudomonas Exotoxin Catalytic Domain for Cancer Therapeutics. Mol Cells 2023; 46:764-777. [PMID: 38052492 PMCID: PMC10701305 DOI: 10.14348/molcells.2023.0155] [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: 09/01/2023] [Revised: 10/10/2023] [Accepted: 10/17/2023] [Indexed: 12/07/2023] Open
Abstract
Recombinant immunotoxins (RITs) are fusion proteins consisting of a targeting domain linked to a toxin, offering a highly specific therapeutic strategy for cancer treatment. In this study, we engineered and characterized RITs aimed at mesothelin, a cell surface glycoprotein overexpressed in various malignancies. Through an extensive screening of a large nanobody library, four mesothelin-specific nanobodies were selected and genetically fused to a truncated Pseudomonas exotoxin (PE24B). Various optimizations, including the incorporation of furin cleavage sites, maltose-binding protein tags, and tobacco etch virus protease cleavage sites, were implemented to improve protein expression, solubility, and purification. The RITs were successfully overexpressed in Escherichia coli, achieving high solubility and purity post-purification. In vitro cytotoxicity assays on gastric carcinoma cell lines NCI-N87 and AGS revealed that Meso(Nb2)-PE24B demonstrated the highest cytotoxic efficacy, warranting further characterization. This RIT also displayed selective binding to human and monkey mesothelins but not to mouse mesothelin. The competitive binding assays between different RIT constructs revealed significant alterations in IC50 values, emphasizing the importance of nanobody specificity. Finally, a modification in the endoplasmic reticulum retention signal at the C-terminus further augmented its cytotoxic activity. Our findings offer valuable insights into the design and optimization of RITs, showcasing the potential of Meso(Nb2)-PE24B as a promising therapeutic candidate for targeted cancer treatment.
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Affiliation(s)
- Minh Quan Nguyen
- Department of Physiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul 05505, Korea
| | | | | | - Huynh Kim Khanh Ta
- Department of Physiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul 05505, Korea
| | - Thi Luong Vu
- Department of Physiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul 05505, Korea
| | - Thi Kieu Oanh Nguyen
- Department of Physiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul 05505, Korea
| | | | - Han Choe
- Department of Physiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul 05505, Korea
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Tul Abiha S, Azeem S, Ahmad Anjum A, Hassan Mushtaq M. Isolation and identification of Clostridium perfringens and its toxins from mutton in Lahore City, Punjab, Pakistan. Vet Ital 2023; 59. [PMID: 38756028 DOI: 10.12834/vetit.2926.20055.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 11/29/2022] [Indexed: 05/18/2024]
Abstract
The present study was aimed to detect C. perfringens and identify its toxins in mutton samples collected from Lahore City in the Punjab Province of Pakistan. A total of 40 samples of minced and non‑minced mutton were collected from local butcher and retail shops representing four areas of the city. The samples were subjected to ELISA for the detection of C. perfringens alpha, beta and epsilon toxins. The samples were simultaneously processed for bacterial isolation. The isolates were confirmed both by biochemical testing and a multiplex PCR targeting alpha, beta and epsilon toxin genes of C. perfringens. While 10% (4/40) of the samples were positive for C. perfringens alpha toxins, 17.5% (7/40) of the samples were positive for the alpha toxin gene. The present study indicated that the samples collected from the local butcher shops were contaminated with C. perfringens and its toxins. Interestingly, no such contamination was detected in any of the samples collected from retail meat shops. In conclusion, improper hygienic conditions at butcher shops could lead to the contamination of mutton with C. perfringens and its toxins.
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Affiliation(s)
- Suqaina Tul Abiha
- Institute of Microbiology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, Punjab Pakistan
| | - Shahan Azeem
- University of Veterinary and Animal Sciences, Lahore, Pakistan.
| | - Aftab Ahmad Anjum
- Institute of Microbiology, Faculty of Veterinary Science, University of Veterinary and Animal Sciences, Lahore, Punjab Pakistan
| | - Muhammad Hassan Mushtaq
- Department of Epidemiology and Public Health, Faculty of Veterinary Science, University of Veterinary and Animal Science, Lahore
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Yokoo A, Tsukamoto N, Narita T, Iyonaga S, Nakashima H, Funashima Y, Sato K, Wakamatsu K, Nagasawa Z, Umemura T. [Evaluation of the Clinical Validity of the Clostridioides difficile Nucleic Acid Detection Kit "Smart Gene® CD ToxinB"]. Rinsho Biseibutshu Jinsoku Shindan Kenkyukai Shi 2023; 33:1-6. [PMID: 38229455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
Clostridioides difficile is the most common anaerobic bacterium that causes healthcare-associated infections, and prompt diagnosis and infection control are important because it causes C. difficile infection (CDI). In this evaluation, the C. difficile nucleic acid detection reagent, Smart Gene CD Toxin B (Mizuho Medy Co., Ltd., hereinafter referred to as the "evaluation reagent") was evaluated for its clinical performance in comparison with real-time PCR and toxigenic culture (TC). Measurement of evaluation reagents and real-time PCR were performed on 157 residual stool specimens from suspected CDI patients. For TC, stool culture was performed, and colonies in which C. difficile was identified by a mass spectrometer (MALDI Biotyper) were checked for toxin production using a rapid antigen diagnostic kit. The results of the evaluation reagents showed a high concordance rate; 100% sensitivity (81/81) and 100% specificity (76/76) with real-time PCR, 89.8% sensitivity (79/88), and 97.1% specificity (67/69) with TC. The evaluation reagent enables a simple nucleic acid amplification test (NAAT) in a short time and is thought to be useful in CDI treatment, which requires rapid diagnosis and infection control.
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Affiliation(s)
- Atsumi Yokoo
- Department of Clinical Laboratory, Medical Kouhoukai Takagi Hospital
| | - Nohara Tsukamoto
- Department of Clinical Laboratory, Medical Kouhoukai Takagi Hospital
| | - Taeko Narita
- Department of Clinical Laboratory, Medical Kouhoukai Takagi Hospital
| | - Shoko Iyonaga
- Department of Clinical Laboratory, Medical Kouhoukai Takagi Hospital
| | - Hisae Nakashima
- Department of Clinical Laboratory, Medical Kouhoukai Takagi Hospital
| | - Yumiko Funashima
- Department of Medical Technology and Science, Faculty of Fukuoka Health Care, International University of Health and Welfare. Department of Medical Laboratory Science, Graduate school of Health and Welfare Sciences, International University of Health and Welfare Graduate School
| | - Kenichi Sato
- Department of Medical Technology and Science, Faculty of Fukuoka Health Care, International University of Health and Welfare. Department of Medical Laboratory Science, Graduate school of Health and Welfare Sciences, International University of Health and Welfare Graduate School
| | - Kentaro Wakamatsu
- Department of Respiratory Medicine, National Hospital Organization Omuta National Hospital
| | - Zenzo Nagasawa
- Department of Clinical Laboratory, Medical Kouhoukai Takagi Hospital. Department of Medical Technology and Science, Faculty of Fukuoka Health Care, International University of Health and Welfare. Department of Medical Laboratory Science, Graduate school of Health and Welfare Sciences, International University of Health and Welfare Graduate School
| | - Tsukuru Umemura
- Department of Clinical Laboratory, Medical Kouhoukai Takagi Hospital. Department of Medical Laboratory Science, Graduate school of Health and Welfare Sciences, International University of Health and Welfare Graduate School
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di Leandro L, Colasante M, Pitari G, Ippoliti R. Hosts and Heterologous Expression Strategies of Recombinant Toxins for Therapeutic Purposes. Toxins (Basel) 2023; 15:699. [PMID: 38133203 PMCID: PMC10748335 DOI: 10.3390/toxins15120699] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 12/05/2023] [Accepted: 12/07/2023] [Indexed: 12/23/2023] Open
Abstract
The production of therapeutic recombinant toxins requires careful host cell selection. Bacteria, yeast, and mammalian cells are common choices, but no universal solution exists. Achieving the delicate balance in toxin production is crucial due to potential self-intoxication. Recombinant toxins from various sources find applications in antimicrobials, biotechnology, cancer drugs, and vaccines. "Toxin-based therapy" targets diseased cells using three strategies. Targeted cancer therapy, like antibody-toxin conjugates, fusion toxins, or "suicide gene therapy", can selectively eliminate cancer cells, leaving healthy cells unharmed. Notable toxins from various biological sources may be used as full-length toxins, as plant (saporin) or animal (melittin) toxins, or as isolated domains that are typical of bacterial toxins, including Pseudomonas Exotoxin A (PE) and diphtheria toxin (DT). This paper outlines toxin expression methods and system advantages and disadvantages, emphasizing host cell selection's critical role.
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Affiliation(s)
| | | | | | - Rodolfo Ippoliti
- Department of Life, Health and Environmental Sciences, University of L’Aquila, 67100 L’Aquila, Italy; (L.d.L.); (M.C.); (G.P.)
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Anderson EE, Ilmain JK, Torres VJ. SarS and Rot are necessary for the repression of lukED and lukSF-PV in Staphylococcus aureus. Microbiol Spectr 2023; 11:e0165623. [PMID: 37800956 PMCID: PMC10715151 DOI: 10.1128/spectrum.01656-23] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 08/21/2023] [Indexed: 10/07/2023] Open
Abstract
IMPORTANCE The leukocidins play an important role in disarming the host immune system and promoting infection. While both SarS and Rot have been established as repressors of leukocidins, the importance of each repressor in infection is unclear. Here, we demonstrate that repression by SarS and Rot is not additive and show that in addition to upregulating expression of each other, they are also able to bind concurrently to the leukocidin promoters. These findings suggest that both repressors are necessary for maximal repression of lukED and lukSF-PV and illuminate another complex relationship among Staphylococcus aureus virulence regulators.
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Affiliation(s)
- Exene E. Anderson
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
| | - Juliana K. Ilmain
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
| | - Victor J. Torres
- Department of Microbiology, New York University Grossman School of Medicine, New York, New York, USA
- Department of Host-Microbe Interactions, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
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Goa Y, Du JG, Jirapattharasate C, Galon E, Ji SW, Ran ZG, Xia YQ. A non-toxic recombinant protein rSUMO-CPBm4 as a potential vaccine candidate against Clostridium perfringens type C beta enterotoxemia. Trop Biomed 2023; 40:400-405. [PMID: 38308826 DOI: 10.47665/tb.40.4.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2024]
Abstract
Beta toxin (CPB) is a lethal toxin and plays a key role in enterotoxemia of ruminants caused by Clostridium perfringens type C strain. The existing vaccines based on crude CPB need time-consuming detoxification and difficult quality control steps. In this study, we synthesized the rCPBm4 of C. perfringens type C strain and small ubiquitin-like modifier (SUMO)-tag CPBm4 (rSUMO-CPBm4) by introducing four amino acid substitutions: R212E, Y266A, L268G, and W275A. Compared with rCPBm4, rSUMO-CPBm4 was expressed with higher solubility in Escherichia coli BL21 (DE3). Neither rCPBm4 nor rSUMO-CPBm4 was lethal to mice. Although rCPBm4 and rSUMO-CPBm4 were reactogenic with polyclonal antibodies against crude CPB, rabbits vaccinated with rSUMO-CPBm4 developed significant levels of toxin-neutralizing antibody (TNA) titers that conferred protection against crude toxin challenge. These data suggest that genetically detoxified rSUMO-CPBm4 is a promising subunit vaccine candidate for C. perfringens type C beta enterotoxemia.
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Affiliation(s)
- Y Goa
- The Key Sericultural Laboratory of Agricultural Ministry, College of Biotechnology, Southwest University, Chongqing, 400715, PR China
- Chongqing Auleon Biological Co., Ltd., Rongchang, Chongqing, 402460, PR China
| | - J G Du
- Department of Bacterial Biologics, China Institute of Veterinary Drug Control, No. 8 Zhongguancun South Street, Beijing 100-081, China
| | - C Jirapattharasate
- Department of Pre-Clinic and Applied Animal Science, Faculty of Veterinary Science, Mahidol University, 999 Phutthamonthon Sai4, Salaya, Phutthamonthon, Nakhon Pathom, Thailand, 73170
| | - E Galon
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan
| | - S W Ji
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan
| | - Z G Ran
- Chongqing Auleon Biological Co., Ltd., Rongchang, Chongqing, 402460, PR China
| | - Y Q Xia
- The Key Sericultural Laboratory of Agricultural Ministry, College of Biotechnology, Southwest University, Chongqing, 400715, PR China
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Mao W, Wang Z, Wen S, Lin Y, Gu J, Sun J, Wang H, Cao Q, Xu Y, Xu X, Cai X. LRRC8A promotes Glaesserella parasuis cytolethal distending toxin-induced p53-dependent apoptosis in NPTr cells. Virulence 2023; 14:2287339. [PMID: 38018865 PMCID: PMC10732598 DOI: 10.1080/21505594.2023.2287339] [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: 10/14/2023] [Accepted: 11/19/2023] [Indexed: 11/30/2023] Open
Abstract
Glaesserella parasuis is an early colonizer of the swine upper respiratory tract and can break through the respiratory barrier for further invasion. However, the mechanisms underlying G. parasuis increases epithelial barrier permeability remain unclear. This study demonstrates that G. parasuis cytolethal distending toxin (CDT) induces p53-dependent apoptosis in new-born piglet tracheal (NPTr) cells. Moreover, we report for the first time that leucine-rich repeat-containing protein 8A (LRRC8A), an essential subunit of the volume-regulated anion channel (VRAC), involves in apoptosis of NPTr cells mediated by G. parasuis CDT. Pharmacological inhibition of VRAC with either PPQ-102 or NS3728 largely attenuated CDT-induced apoptosis in NPTr cells. Additionally, experiments with cells knocked down for LRRC8A using small interfering ribonucleic acid (siRNA) or knocked out LRRC8A using CRISPR/Cas9 technology showed a significant reduction in CDT-induced apoptosis. Conversely, re-expression of Sus scrofa LRRC8A in LRRC8A-/- NPTr cells efficiently complemented the CDT-induced apoptosis. In summary, these findings suggest that LRRC8A is pivotal for G. parasuis CDT-induced apoptosis, providing novel insights into the mechanism of apoptosis caused by CDT.
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Affiliation(s)
- Weiting Mao
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Zhichao Wang
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Siting Wen
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
| | - Yan Lin
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
| | - Jiayun Gu
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
| | - Ju Sun
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
| | - Huan Wang
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
| | - Qi Cao
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
| | - Yindi Xu
- Institute of Animal Husbandry and Veterinary Research, Henan Academy of Agricultural Sciences, Zhengzhou, China
| | - Xiaojuan Xu
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
| | - Xuwang Cai
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China
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González-Magaña A, Tascón I, Altuna-Alvarez J, Queralt-Martín M, Colautti J, Velázquez C, Zabala M, Rojas-Palomino J, Cárdenas M, Alcaraz A, Whitney JC, Ubarretxena-Belandia I, Albesa-Jové D. Structural and functional insights into the delivery of a bacterial Rhs pore-forming toxin to the membrane. Nat Commun 2023; 14:7808. [PMID: 38016939 PMCID: PMC10684867 DOI: 10.1038/s41467-023-43585-5] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 11/14/2023] [Indexed: 11/30/2023] Open
Abstract
Bacterial competition is a significant driver of toxin polymorphism, which allows continual compensatory evolution between toxins and the resistance developed to overcome their activity. Bacterial Rearrangement hot spot (Rhs) proteins represent a widespread example of toxin polymorphism. Here, we present the 2.45 Å cryo-electron microscopy structure of Tse5, an Rhs protein central to Pseudomonas aeruginosa type VI secretion system-mediated bacterial competition. This structural insight, coupled with an extensive array of biophysical and genetic investigations, unravels the multifaceted functional mechanisms of Tse5. The data suggest that interfacial Tse5-membrane binding delivers its encapsulated pore-forming toxin fragment to the target bacterial membrane, where it assembles pores that cause cell depolarisation and, ultimately, bacterial death.
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Affiliation(s)
- Amaia González-Magaña
- Instituto Biofisika (CSIC, UPV/EHU), Fundación Biofísica Bizkaia/Biofisika Bizkaia Fundazioa (FBB), 48940, Leioa, Spain
- Departamento de Bioquímica y Biología Molecular, University of the Basque Country, 48940, Leioa, Spain
| | - Igor Tascón
- Instituto Biofisika (CSIC, UPV/EHU), Fundación Biofísica Bizkaia/Biofisika Bizkaia Fundazioa (FBB), 48940, Leioa, Spain
- Ikerbasque, Basque Foundation for Science, 48013, Bilbao, Spain
| | - Jon Altuna-Alvarez
- Instituto Biofisika (CSIC, UPV/EHU), Fundación Biofísica Bizkaia/Biofisika Bizkaia Fundazioa (FBB), 48940, Leioa, Spain
| | - María Queralt-Martín
- Laboratory of Molecular Biophysics, Department of Physics, University Jaume I, 12071, Castellón, Spain
| | - Jake Colautti
- Department of Biochemistry and Biomedical Sciences, Michael DeGroote Institute for Infectious Disease Research, and David Braley Centre for Antibiotic Discovery, McMaster University, Hamilton, Canada
| | - Carmen Velázquez
- Instituto Biofisika (CSIC, UPV/EHU), Fundación Biofísica Bizkaia/Biofisika Bizkaia Fundazioa (FBB), 48940, Leioa, Spain
- Departamento de Bioquímica y Biología Molecular, University of the Basque Country, 48940, Leioa, Spain
| | - Maialen Zabala
- Instituto Biofisika (CSIC, UPV/EHU), Fundación Biofísica Bizkaia/Biofisika Bizkaia Fundazioa (FBB), 48940, Leioa, Spain
- Departamento de Bioquímica y Biología Molecular, University of the Basque Country, 48940, Leioa, Spain
| | - Jessica Rojas-Palomino
- Laboratory of Molecular Biophysics, Department of Physics, University Jaume I, 12071, Castellón, Spain
| | - Marité Cárdenas
- Instituto Biofisika (CSIC, UPV/EHU), Fundación Biofísica Bizkaia/Biofisika Bizkaia Fundazioa (FBB), 48940, Leioa, Spain
- Ikerbasque, Basque Foundation for Science, 48013, Bilbao, Spain
| | - Antonio Alcaraz
- Laboratory of Molecular Biophysics, Department of Physics, University Jaume I, 12071, Castellón, Spain
| | - John C Whitney
- Department of Biochemistry and Biomedical Sciences, Michael DeGroote Institute for Infectious Disease Research, and David Braley Centre for Antibiotic Discovery, McMaster University, Hamilton, Canada
| | - Iban Ubarretxena-Belandia
- Instituto Biofisika (CSIC, UPV/EHU), Fundación Biofísica Bizkaia/Biofisika Bizkaia Fundazioa (FBB), 48940, Leioa, Spain.
- Ikerbasque, Basque Foundation for Science, 48013, Bilbao, Spain.
| | - David Albesa-Jové
- Instituto Biofisika (CSIC, UPV/EHU), Fundación Biofísica Bizkaia/Biofisika Bizkaia Fundazioa (FBB), 48940, Leioa, Spain.
- Departamento de Bioquímica y Biología Molecular, University of the Basque Country, 48940, Leioa, Spain.
- Ikerbasque, Basque Foundation for Science, 48013, Bilbao, Spain.
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Ali BN, Saeed AY, Abdulmawjood A. Detection of Clostridium difficile among diarrheic children using cultural and polymerase chain reaction technique. J Infect Dev Ctries 2023; 17:1452-1457. [PMID: 37956379 DOI: 10.3855/jidc.17473] [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: 09/30/2022] [Accepted: 04/05/2023] [Indexed: 11/15/2023] Open
Abstract
INTRODUCTION Clostridium difficile is the most common cause of antibiotic-associated diarrhea and colitis. Several methods are available for the detection of C. difficile in stool samples. This study aimed to use glutamate dehydrogenase (GDH), toxin detection, culture and polymerase chain reaction (PCR) techniques for the diagnosis of this pathogen. METHODOLOGY A total of 300 stool samples were collected from children with hospital acquired diarrhea (HA-D), community acquired diarrhea (CA-D), and hospitalized non-diarrheic children as control with ages ranging from 6 months to 6 years (mean 3.7 ± 1.7). Each stool sample was divided into two parts; one part was tested for the enzyme GDH, toxin A and B and then cultured on selective media; and the other part for direct DNA extraction. RESULTS From a total of 300 stool samples, 9 (3.0%) were positive for C. difficile by the PCR technique, 7 (7%) samples of which were from HA-D cases and 2 (2.0%) from CA-D cases; the control group samples were negative. The enzyme GDH was detected in 12 (12%) samples and toxins A and B in 8 (8%) samples from HA-D cases compared to 5 (5%) and 2 (2%), respectively from CA-D cases. Both GDH and the toxins were negative in control samples. Only 19 (19.0%) samples from HA-D cases gave suspected growth and all of these were negative by PCR. CONCLUSIONS Based on the results of this study, we conclude that the PCR technique is the only reliable method for the diagnosis of this pathogen.
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Affiliation(s)
- Bakhtyar Nader Ali
- Duhok Research Center, College of Science, University of Duhok, Duhok, Iraq
| | - Ali Yahya Saeed
- Department of Biology, College of Science, University of Duhok, Duhok, Iraq
| | - Amir Abdulmawjood
- Institute for Food Quality and Food Safety, University of Veterinary Medicine Hannover, Hannover, Germany
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46
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Maestri AC, Mesa D, Vasconcelos TM, Krul D, Ricieri MC, Motta FA, Dalla-Costa LM, Raboni SM, Nogueira KS. Analysis of Clostridioides difficile Infection in Children with Diarrhea in Two Hospitals in Southern Brazil. Curr Microbiol 2023; 80:390. [PMID: 37884782 DOI: 10.1007/s00284-023-03499-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 09/24/2023] [Indexed: 10/28/2023]
Abstract
Clostridioides difficile infection (CDI) has been increasingly observed in children, but there is a lack of epidemiological and molecular data on CDI in Latin America. This prospective cohort study aimed to investigate the role of CDI in children with diarrhea. It included 105 children with antimicrobial-associated diarrhea (AAD) and analyzed the molecular characteristics of strains isolated from two hospitals in southern Brazil between 2017 and 2020. Fecal samples from the participants were tested for glutamate dehydrogenase (GDH) and A/B toxins using a rapid enzyme immunoassay. GDH-positive samples underwent automated real-time polymerase chain reaction and toxigenic culture. Toxigenic C. difficile isolates were selected for whole genome sequencing. Out of the 105 patients, 14 (13.3%) met the criteria for CDI. Children with a history of previous CDI and the presence of mucus in their stool were more likely to have CDI. Metronidazole was the most used treatment (71.4%), and three patients (23.1%) experienced CDI recurrence (rCDI). Although the number of sequenced isolates was limited, a wide diversity of sequence types (ST) was observed. In addition to toxin genes (tcdA, tcdB, cdtA, and cdtB), the isolates also exhibited virulence factors involved in adhesion (cwp66, groEL, slpA, fbpA/fbp68) and immune evasion (rmlA, rmlB, rmlC, gnd, rfbA-1), along with multiple resistance factors (gyrA mutation, norA, ermB, dfrF, and vanG). These findings highlight the prevalence and recurrence of CDI among hospitalized children. Longitudinal studies are needed to better understand the characteristics of CDI-associated diarrhea and its impact on the healthcare system in this population.
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Affiliation(s)
- Adriane C Maestri
- Laboratório de Bacteriologia, Complexo Hospital de Clínicas da Universidade Federal do Paraná, Rua Padre Camargo, 280 - Alto da Glória, CEP: 80.062-240, Curitiba, Paraná, Brazil
- Programa de Pós-Graduação em Medicina Interna e Ciências da Saúde, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
| | - Dany Mesa
- Faculdades Pequeno Príncipe/ Instituto de Pesquisa Pelé Pequeno Príncipe, Curitiba, Paraná, Brazil
| | - Thais M Vasconcelos
- Faculdades Pequeno Príncipe/ Instituto de Pesquisa Pelé Pequeno Príncipe, Curitiba, Paraná, Brazil
| | - Damaris Krul
- Faculdades Pequeno Príncipe/ Instituto de Pesquisa Pelé Pequeno Príncipe, Curitiba, Paraná, Brazil
| | | | | | - Libera M Dalla-Costa
- Faculdades Pequeno Príncipe/ Instituto de Pesquisa Pelé Pequeno Príncipe, Curitiba, Paraná, Brazil
| | - Sonia M Raboni
- Programa de Pós-Graduação em Medicina Interna e Ciências da Saúde, Universidade Federal do Paraná, Curitiba, Paraná, Brazil
- Departamento de Infectologia, Complexo Hospital de Clínicas da Universidade Federal do Paraná, Curitiba, Paraná, Brazil
| | - Keite S Nogueira
- Laboratório de Bacteriologia, Complexo Hospital de Clínicas da Universidade Federal do Paraná, Rua Padre Camargo, 280 - Alto da Glória, CEP: 80.062-240, Curitiba, Paraná, Brazil.
- Programa de Pós-Graduação em Microbiologia, Parasitologia e Patologia, Universidade Federal do Paraná, Curitiba, Paraná, Brazil.
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Leite S, Cotias C, Rainha KC, Santos MG, Penna B, F Moraes RF, Harmanus C, Smits WK, Ferreira EDO. Prevalence of Clostridioides difficile in dogs (Canis familiaris) with gastrointestinal disorders in Rio de Janeiro. Anaerobe 2023; 83:102765. [PMID: 37573963 DOI: 10.1016/j.anaerobe.2023.102765] [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: 04/04/2023] [Revised: 07/18/2023] [Accepted: 07/19/2023] [Indexed: 08/15/2023]
Abstract
Clostridioides difficile infections (CDI) have a high morbidity and mortality rate and have always been considered a nosocomial disease. Nonetheless, the number of cases of community-acquired CDI is increasing, and new evidence suggests additional C. difficile reservoirs exist. Pathogenic C. difficile strains have been found in livestock, domestic animals, and meat, so a zoonotic transmission has been proposed. OBJECTIVE The goal of this study was to isolate C. difficile strains in dogs at a veterinary clinic in Rio de Janeiro, Brazil, and characterize clinical and pathological findings associated with lower gastrointestinal tract disorders. METHODS Fifty stool samples and biopsy fragments from dogs were obtained and cultured in the CDBA selective medium. All suggestive C. difficile colonies were confirmed by MALDI-TOF MS and PCR (tpi gene). Vancomycin, metronidazole, moxifloxacin, erythromycin, and rifampicin were tested for antibiotic susceptibility. Biofilm, motility assays, and a PCR for the toxins (tcdA, tcdB, and cdtB), as well as ribotyping, were also performed. RESULTS Blood samples and colonic biopsy fragments were examined in C. difficile positive dogs. Ten animals (20%) tested positive for C. difficile by using stool samples, but not from biopsy fragments. Most C. difficile strains were toxigenic: six were A+B+ belonging to RT106; two were A+B+ belonging to RT014/020; and two were A-B- belonging to RT010. All strains were biofilm producers. In the motility test, 40% of strains were as motile as the positive control, CD630 (RT012). In the disc diffusion test, two strains (RT010) were resistant to erythromycin and metronidazole; and another to metronidazole (RT014/020). In terms of C. difficile clinicopathological correlations, no statistically significant morphological changes, such as pseudomembranous and "volcano" lesions, were observed. Regarding hematological data, dogs positive for C. difficile had leucopenia (p = 0.02) and lymphopenia (p = 0.03). There was a significant correlation between senility and the presence of C. difficile in the dogs studied (p = 0,02). CONCLUSIONS Although C. difficile has not been linked to canine diarrheal disorders, it appears to be more common in dogs with intestinal dysfunctions. The isolation of ribotypes frequently involved in human CDI outbreaks around the world supports the theory of C. difficile zoonotic transmission.
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Affiliation(s)
- Suzana Leite
- Departmento de Microbiologia Médica, Instituto de Microbiologia Paulo de Góes -IMPG, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; Universidade Santa Úrsula, Rio de Janeiro, Brazil
| | - Carlos Cotias
- H&Diagnóstico, Veterinary Diagnosis Center, Rio de Janeiro, Brazil
| | | | | | - Bruno Penna
- Departmento de Microbiologia e Parasitologia, Instituto de Biomedicina, Universidade Federal Fluminense- UFF, Niterói, Brazil
| | | | - Céline Harmanus
- Department of Medical Microbiology, Leiden University Medical Center, Leiden, Netherlands
| | - Wiep Klaas Smits
- Department of Medical Microbiology, Leiden University Medical Center, Leiden, Netherlands
| | - Eliane de Oliveira Ferreira
- Departmento de Microbiologia Médica, Instituto de Microbiologia Paulo de Góes -IMPG, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
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Dominguez-Molina L, Talavera A, Cepauskas A, Kurata T, Echemendia-Blanco D, Hauryliuk V, Garcia-Pino A. Biochemical and X-ray analyses of the players involved in the faRel2/aTfaRel2 toxin-antitoxin operon. Acta Crystallogr F Struct Biol Commun 2023; 79:247-256. [PMID: 37728608 PMCID: PMC10565793 DOI: 10.1107/s2053230x23007288] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 08/19/2023] [Indexed: 09/21/2023] Open
Abstract
The aTfaRel2/faRel2 operon from Coprobacillus sp. D7 encodes a bicistronic type II toxin-antitoxin (TA) module. The FaRel2 toxin is a toxic small alarmone synthetase (toxSAS) that inhibits translation through the pyrophosphorylation of uncharged tRNAs at the 3'-CCA end. The toxin is neutralized by the antitoxin ATfaRel2 through the formation of an inactive TA complex. Here, the production, biophysical analysis and crystallization of ATfaRel2 and FaRel2 as well as of the ATfaRel2-FaRel2 complex are reported. ATfaRel2 is monomeric in solution. The antitoxin crystallized in space group P21212 with unit-cell parameters a = 53.3, b = 34.2, c = 37.6 Å, and the best crystal diffracted to a resolution of 1.24 Å. Crystals of FaRel2 in complex with APCPP, a nonhydrolysable ATP analogue, belonged to space group P21, with unit-cell parameters a = 31.5, b = 60.6, c = 177.2 Å, β = 90.6°, and diffracted to 2.6 Å resolution. The ATfaRel2-FaRel2Y128F complex forms a heterotetramer in solution composed of two toxins and two antitoxins. This complex crystallized in two space groups: F4132, with unit-cell parameters a = b = c = 227.1 Å, and P212121, with unit-cell parameters a = 51.7, b = 106.2, c = 135.1 Å. The crystals diffracted to 1.98 and 2.1 Å resolution, respectively.
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Affiliation(s)
- Lucia Dominguez-Molina
- Cellular and Molecular Microbiology, Faculté des Sciences, Université Libre de Bruxelles (ULB), Boulevard du Triomphe, Building BC (1C4 203), 1050 Brussels, Belgium
| | - Ariel Talavera
- Cellular and Molecular Microbiology, Faculté des Sciences, Université Libre de Bruxelles (ULB), Boulevard du Triomphe, Building BC (1C4 203), 1050 Brussels, Belgium
| | - Albinas Cepauskas
- Cellular and Molecular Microbiology, Faculté des Sciences, Université Libre de Bruxelles (ULB), Boulevard du Triomphe, Building BC (1C4 203), 1050 Brussels, Belgium
| | - Tatsuaki Kurata
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Dannele Echemendia-Blanco
- Cellular and Molecular Microbiology, Faculté des Sciences, Université Libre de Bruxelles (ULB), Boulevard du Triomphe, Building BC (1C4 203), 1050 Brussels, Belgium
| | - Vasili Hauryliuk
- Department of Experimental Medical Science, Lund University, Lund, Sweden
- University of Tartu Institute of Technology, Tartu, Estonia
- Science for Life Laboratory, Lund, Sweden
| | - Abel Garcia-Pino
- Cellular and Molecular Microbiology, Faculté des Sciences, Université Libre de Bruxelles (ULB), Boulevard du Triomphe, Building BC (1C4 203), 1050 Brussels, Belgium
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Kordus SL, Kroh HK, Rodríguez RC, Shrem RA, Peritore-Galve FC, Shupe JA, Wadzinski BE, Lacy DB, Spiller BW. Nanobodies against C. difficile TcdA and TcdB reveal unexpected neutralizing epitopes and provide a toolkit for toxin quantitation in vivo. PLoS Pathog 2023; 19:e1011496. [PMID: 37871122 PMCID: PMC10621975 DOI: 10.1371/journal.ppat.1011496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 11/02/2023] [Accepted: 10/07/2023] [Indexed: 10/25/2023] Open
Abstract
Clostridioides difficile is a leading cause of antibiotic-associated diarrhea and nosocomial infection in the United States. The symptoms of C. difficile infection (CDI) are associated with the production of two homologous protein toxins, TcdA and TcdB. The toxins are considered bona fide targets for clinical diagnosis as well as the development of novel prevention and therapeutic strategies. While there are extensive studies that document these efforts, there are several gaps in knowledge that could benefit from the creation of new research tools. First, we now appreciate that while TcdA sequences are conserved, TcdB sequences can vary across the span of circulating clinical isolates. An understanding of the TcdA and TcdB epitopes that drive broadly neutralizing antibody responses could advance the effort to identify safe and effective toxin-protein chimeras and fragments for vaccine development. Further, an understanding of TcdA and TcdB concentration changes in vivo can guide research into how host and microbiome-focused interventions affect the virulence potential of C. difficile. We have developed a panel of alpaca-derived nanobodies that bind specific structural and functional domains of TcdA and TcdB. We note that many of the potent neutralizers of TcdA bind epitopes within the delivery domain, a finding that could reflect roles of the delivery domain in receptor binding and/or the conserved role of pore-formation in the delivery of the toxin enzyme domains to the cytosol. In contrast, neutralizing epitopes for TcdB were found in multiple domains. The nanobodies were also used for the creation of sandwich ELISA assays that allow for quantitation of TcdA and/or TcdB in vitro and in the cecal and fecal contents of infected mice. We anticipate these reagents and assays will allow researchers to monitor the dynamics of TcdA and TcdB production over time, and the impact of various experimental interventions on toxin production in vivo.
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Affiliation(s)
- Shannon L. Kordus
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Heather K. Kroh
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Rubén Cano Rodríguez
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Rebecca A. Shrem
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - F. Christopher Peritore-Galve
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - John A. Shupe
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Brian E. Wadzinski
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - D. Borden Lacy
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, Tennessee, United States of America
| | - Benjamin W. Spiller
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee, United States of America
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50
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Sun Y, Zhang Y, Yu H, Saint Fleur A, Yu D, Yang Z, Feng H. A fine-tuned yeast surface-display/secretion platform enables the rapid discovery of neutralizing antibodies against Clostridioides difficile toxins. Microb Cell Fact 2023; 22:194. [PMID: 37749574 PMCID: PMC10519002 DOI: 10.1186/s12934-023-02200-4] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 09/06/2023] [Indexed: 09/27/2023] Open
Abstract
BACKGROUND Neutralizing antibody plays a key role in protecting hosts from invasive pathogens and their virulent components. Current high-throughput assays for antibody screening are based on binding activities. However, those antibodies with high affinity may not have neutralizing activities. Subsequent functionality assays are necessary to identify neutralizing antibodies from binders with high affinity to their target antigens, which is laborious and time-consuming. Therefore, a versatile platform that can rapidly identify antibodies with both high binding affinity and neutralizing activity is desired to curb future pandemics like COVID-19. RESULTS In this proof-of-concept study, we adapted Saccharomyces cerevisiae to either display human antibodies on the yeast surface or secrete soluble antibodies into the cultivation supernatant under a controllable 'switch' through different carbon source induced promoters. Initially, an engineered chimeric-bispecific Fab antibody, derived from humanized nanobodies against both Clostridioides difficile toxin A and B (TcdA and TcdB), was successfully expressed either on the yeast cell surface or in the culture medium with intact bioactivity, suggesting the applicability of our system in antibody display and secretion. Next, a combinatorial Fab library was constructed from B cells isolated from a convalescent patient with a high serological neutralizing titer against TcdB. Following three rounds of magnetic bead enrichment and one round of flow cytometry sorting, antibodies against TcdB were enriched efficiently. We then sorted out single binders with high binding affinity and induced them to express soluble antibodies in culture medium. The neutralizing activity of culture supernatant was analyzed using cell-based assay immediately. This way, we rapidly identified two unique neutralizers (out of seven binders) that can neutralize the cytotoxicity of TcdB. CONCLUSION The antibody screening platform described here simplifies the neutralizing antibody discovery procedure and will be an attractive alternative for screening functional antibodies against infectious diseases.
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Affiliation(s)
- Ying Sun
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD, 21201, USA.
- Department of Pathogen Biology, School of Basic Medical Sciences, China Medical University, Shenyang, 110122, China.
| | - Yongrong Zhang
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD, 21201, USA
| | - Hua Yu
- Fzata, Inc, Halethorpe, MD, 21227, USA
| | - Ashley Saint Fleur
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD, 21201, USA
| | - Di Yu
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD, 21201, USA
| | | | - Hanping Feng
- Department of Microbial Pathogenesis, School of Dentistry, University of Maryland, Baltimore, MD, 21201, USA.
- Fzata, Inc, Halethorpe, MD, 21227, USA.
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