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Liu Q, Shang Y, Shen L, Yu X, Cao Y, Zeng L, Zhang H, Rao Z, Li Y, Tao Z, Liu Z, Huang X. Outer membrane vesicles from genetically engineered Salmonella enterica serovar Typhimurium presenting Helicobacter pylori antigens UreB and CagA induce protection against Helicobacter pylori infection in mice. Virulence 2024; 15:2367783. [PMID: 38937901 PMCID: PMC11216100 DOI: 10.1080/21505594.2024.2367783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Accepted: 06/09/2024] [Indexed: 06/29/2024] Open
Abstract
Helicobacter pylori causes globally prevalent infections that are highly related to chronic gastritis and even development of gastric carcinomas. With the increase of antibiotic resistance, scientists have begun to search for better vaccine design strategies to eradicate H. pylori colonization. However, while current strategies prefer to formulate vaccines with a single H. pylori antigen, their potential has not yet been fully realized. Outer membrane vesicles (OMVs) are a potential platform since they could deliver multiple antigens. In this study, we engineered three crucial H. pylori antigen proteins (UreB, CagA, and VacA) onto the surface of OMVs derived from Salmonella enterica serovar Typhimurium (S. Typhimurium) mutant strains using the hemoglobin protease (Hbp) autotransporter system. In various knockout strategies, we found that OMVs isolated from the ΔrfbP ΔfliC ΔfljB ΔompA mutants could cause distinct increases in immunoglobulin G (IgG) and A (IgA) levels and effectively trigger T helper 1- and 17-biased cellular immune responses, which perform a vital role in protecting against H. pylori. Next, OMVs derived from ΔrfbP ΔfliC ΔfljB ΔompA mutants were used as a vector to deliver different combinations of H. pylori antigens. The antibody and cytokine levels and challenge experiments in mice model indicated that co-delivering UreB and CagA could protect against H. pylori and antigen-specific T cell responses. In summary, OMVs derived from the S. Typhimurium ΔrfbP ΔfliC ΔfljB ΔompA mutant strain as the vector while importing H. pylori UreB and CagA as antigenic proteins using the Hbp autotransporter system would greatly benefit controlling H. pylori infection.
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Affiliation(s)
- Qiong Liu
- The First Affiliated Hospital, School of Basic Medical Sciences, Jiangxi Medical College, Nanchang University
| | - Yinpan Shang
- The First Affiliated Hospital, School of Basic Medical Sciences, Jiangxi Medical College, Nanchang University
| | - Lu Shen
- The First Affiliated Hospital, School of Basic Medical Sciences, Jiangxi Medical College, Nanchang University
| | - Xiaomin Yu
- The First Affiliated Hospital, School of Basic Medical Sciences, Jiangxi Medical College, Nanchang University
| | - Yanli Cao
- The First Affiliated Hospital, School of Basic Medical Sciences, Jiangxi Medical College, Nanchang University
| | - Lingbing Zeng
- The First Affiliated Hospital, School of Basic Medical Sciences, Jiangxi Medical College, Nanchang University
| | - Hanchi Zhang
- The First Affiliated Hospital, School of Basic Medical Sciences, Jiangxi Medical College, Nanchang University
- The Second Clinical Medical College, Nanchang University, Nanchang, China
| | - Zirong Rao
- The First Affiliated Hospital, School of Basic Medical Sciences, Jiangxi Medical College, Nanchang University
- HuanKui Academy, Nanchang University, Nanchang, China
| | - Yi Li
- The First Affiliated Hospital, School of Basic Medical Sciences, Jiangxi Medical College, Nanchang University
- The First Clinical Medical College, Nanchang University, Nanchang, China
| | - Ziwei Tao
- The First Affiliated Hospital, School of Basic Medical Sciences, Jiangxi Medical College, Nanchang University
| | - Zhili Liu
- The First Affiliated Hospital, School of Basic Medical Sciences, Jiangxi Medical College, Nanchang University
- HuanKui Academy, Nanchang University, Nanchang, China
| | - Xiaotian Huang
- The First Affiliated Hospital, School of Basic Medical Sciences, Jiangxi Medical College, Nanchang University
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2
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Liang K, Zhang R, Luo H, Zhang J, Tian Z, Zhang X, Zhang Y, Ali MK, Kong Q. Optimized Attenuated Salmonella Typhimurium Suppressed Tumor Growth and Improved Survival in Mice. Front Microbiol 2022; 12:774490. [PMID: 35003007 PMCID: PMC8733734 DOI: 10.3389/fmicb.2021.774490] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 12/02/2021] [Indexed: 01/03/2023] Open
Abstract
The gram-negative facultative anaerobic bacteria Salmonella enterica serovar Typhimurium (hereafter S. Typhimurium) has always been considered as one candidate of anti-tumor agents or vectors for delivering drug molecules. In this study, we compared several widely studied S. Typhimurium strains in their anti-tumor properties aiming to screen out the best one for further optimization and use in cancer therapy. In terms of the motility, virulence and anti-tumor efficacy, the three strains 14028, SL1344, and UK-1 were similar and obviously better than LT-2, and UK-1 showed the best phenotypes among them. Therefore, the strain UK-1 (D) was selected for the following studies. Its auxotrophic mutant strain (D1) harboring ∆aroA and ∆purM mutations was further optimized through the modification of lipid A structure, generating a new strain named D2 with stronger immunostimulatory activity. Finally, the ∆asd derivative of D2 was utilized as one live vector to deliver anti-tumor molecules including the angiogenesis inhibitor endostatin and apoptosis inducer TRAIL and the therapeutic and toxic-side effects were evaluated in mouse models of colon carcinoma and melanoma. After intraperitoneal infection, engineered Salmonella bacteria equipped with endostatin and/or TRAIL significantly suppressed the tumor growth and prolonged survival of tumor-bearing mice compared to PBS or bacteria carrying the empty plasmid. Consistently, immunohistochemical studies confirmed the colonization of Salmonella bacteria and the expression of anti-tumor molecules inside tumor tissue, which were accompanied by the increase of cell apoptosis and suppression of tumor angiogenesis. These results demonstrated that the beneficial anti-tumor efficacy of attenuated S. Typhimurium bacteria could be improved through delivery of drug molecules with powerful anti-tumor activities.
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Affiliation(s)
- Kang Liang
- College of Veterinary Medicine, Southwest University, Chongqing, China
| | - Rui Zhang
- College of Veterinary Medicine, Southwest University, Chongqing, China
| | - Haiyan Luo
- College of Veterinary Medicine, Southwest University, Chongqing, China
| | - Jinlong Zhang
- College of Veterinary Medicine, Southwest University, Chongqing, China
| | - Zhenyuan Tian
- College of Veterinary Medicine, Southwest University, Chongqing, China
| | - Xiaofen Zhang
- College of Veterinary Medicine, Southwest University, Chongqing, China
| | - Yulin Zhang
- College of Veterinary Medicine, Southwest University, Chongqing, China
| | - Md Kaisar Ali
- College of Veterinary Medicine, Southwest University, Chongqing, China
| | - Qingke Kong
- College of Veterinary Medicine, Southwest University, Chongqing, China
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3
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Tian H, Li B, Xu T, Yu H, Chen J, Yu H, Li S, Zeng L, Huang X, Liu Q. Outer Membrane Vesicles Derived from Salmonella enterica Serotype Typhimurium Can Deliver Shigella flexneri 2a O-Polysaccharide Antigen To Prevent Shigella flexneri 2a Infection in Mice. Appl Environ Microbiol 2021; 87:e0096821. [PMID: 34319809 PMCID: PMC8432525 DOI: 10.1128/aem.00968-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 07/19/2021] [Indexed: 11/20/2022] Open
Abstract
Shigellosis has become a serious threat to health in many developing countries due to the severe diarrhea it causes. Shigella flexneri 2a is the principal species responsible for this endemic disease. Despite multiple attempts to design a vaccine against shigellosis, no effective vaccine has been developed yet. Lipopolysaccharide (LPS) is both an essential virulence factor and an antigen protective against Shigella, due to its outer domain, termed O-polysaccharide antigen. In the present study, S. flexneri 2a O-polysaccharide antigen was innovatively biosynthesized in Salmonella and attached to core-lipid A via the ligase WaaL, with purified outer membrane vesicles (OMVs) utilized as vaccine vectors. Here, we identified the expression of the heterologous O-antigen and have described the isolation, characterization, and immune protection efficiency of the OMV vaccine. Furthermore, the results of animal experiments indicated that immunization of mice with the OMV vaccine induced significant specific anti-Shigella LPS antibodies in the serum, with similar trends in IgA levels from vaginal secretions and fluid from bronchopulmonary lavage, both intranasally and intraperitoneally. The OMV vaccine derived from both routes of administration provided significant protection against virulent S. flexneri 2a infection, as judged by a serum bactericidal assay, opsonization assay, and challenge test. This vaccination strategy represents a novel and improved approach to control shigellosis by the combination of Salmonella glycosyl carrier lipid bioconjugation with OMVs. IMPORTANCEShigella, the cause of shigellosis or bacillary dysentery, is a major public health concern, especially for children in developing countries. An effective vaccine would control the spread of the disease to some extent. However, no licensed vaccine against Shigella infection in humans has so far been developed. The Shigella O-antigen polysaccharide is effective in stimulating the production of protective antibodies and so could represent a vaccine antigen candidate. In addition, bacterial outer membrane vesicles (OMVs) have been used as antigen delivery platforms due to their nanoscale properties and ease of antigen delivery to trigger an immune response. Therefore, the present study provides a new strategy for vaccine design, combining a glycoconjugated vaccine with OMVs. The design concept of this strategy is the expression of Shigella O-antigen via the LPS synthesis pathway in recombinant Salmonella, from which the OMV vaccine is then isolated. Based on these findings, we believe that the novel vaccine design strategy in which polysaccharide antigens are delivered via bacterial OMVs will be effective for the development and clinical application of an effective Shigella vaccine.
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Affiliation(s)
- Huizhen Tian
- Department of Medical Microbiology, School of Medicine, Nanchang University, Nanchang, China
| | - Biaoxian Li
- Department of Medical Microbiology, School of Medicine, Nanchang University, Nanchang, China
| | - Tian Xu
- Department of Medical Microbiology, School of Medicine, Nanchang University, Nanchang, China
| | - Haolin Yu
- School of Ophthalmology and Optometry, Nanchang University, Nanchang, China
| | - Jingxuan Chen
- School of Ophthalmology and Optometry, Nanchang University, Nanchang, China
| | - Haiyan Yu
- Department of Medical Microbiology, School of Medicine, Nanchang University, Nanchang, China
| | - Shan Li
- Department of Medical Microbiology, School of Medicine, Nanchang University, Nanchang, China
| | - Lingbing Zeng
- The First Affiliated Hospital of Nanchang University, Nanchang, China
| | - Xiaotian Huang
- Department of Medical Microbiology, School of Medicine, Nanchang University, Nanchang, China
| | - Qiong Liu
- Department of Medical Microbiology, School of Medicine, Nanchang University, Nanchang, China
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
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Takemura M, Haneda T, Idei H, Miki T, Okada N. A Salmonella type III effector, PipA, works in a different manner than the PipA family effectors GogA and GtgA. PLoS One 2021; 16:e0248975. [PMID: 33735297 PMCID: PMC7971870 DOI: 10.1371/journal.pone.0248975] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 03/08/2021] [Indexed: 12/31/2022] Open
Abstract
Nuclear factor-kappa B (NF-κB) plays a critical role in the host defense against microbial pathogens. Many pathogens modulate NF-κB signaling to establish infection in their host. Salmonella enterica serovar Typhimurium (S. Typhimurium) possesses two type III secretion systems (T3SS-1 and T3SS-2) and directly injects many effector proteins into host cells. It has been reported that some effectors block NF-κB signaling, but the molecular mechanism of the inactivation of NF-κB signaling in S. Typhimurium is poorly understood. Here, we identified seven type III effectors-GogA, GtgA, PipA, SseK1, SseK2, SseK3, and SteE-that inhibited NF-κB activation in HeLa cells stimulated with TNF-α. We also determined that only GogA and GtgA are involved in regulation of the activation of NF-κB in HeLa cells infected with S. Typhimurium. GogA, GtgA, and PipA are highly homologous to one another and have the consensus zinc metalloprotease HEXXH motif. Our experiments demonstrated that GogA, GtgA, and PipA each directly cleaved NF-κB p65, whereas GogA and GtgA, but not PipA, inhibited the NF-κB activation in HeLa cells infected with S. Typhimurium. Further, expressions of the gogA or gtgA gene were induced under the SPI-1-and SPI-2-inducing conditions, but expression of the pipA gene was induced only under the SPI-2-inducing condition. We also showed that PipA was secreted into RAW264.7 cells through T3SS-2. Finally, we indicated that PipA elicits bacterial dissemination in the systemic stage of infection of S. Typhimurium via a T3SS-1-independent mechanism. Collectively, our results suggest that PipA, GogA and GtgA contribute to S. Typhimurium pathogenesis in different ways.
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Affiliation(s)
- Momo Takemura
- Laboratory of Microbiology, School of Pharmacy, Kitasato University, Minato, Tokyo, Japan
| | - Takeshi Haneda
- Laboratory of Microbiology, School of Pharmacy, Kitasato University, Minato, Tokyo, Japan
- * E-mail:
| | - Hikari Idei
- Laboratory of Microbiology, School of Pharmacy, Kitasato University, Minato, Tokyo, Japan
| | - Tsuyoshi Miki
- Laboratory of Microbiology, School of Pharmacy, Kitasato University, Minato, Tokyo, Japan
| | - Nobuhiko Okada
- Laboratory of Microbiology, School of Pharmacy, Kitasato University, Minato, Tokyo, Japan
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5
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Redweik GAJ, Jochum J, Mellata M. Live Bacterial Prophylactics in Modern Poultry. Front Vet Sci 2020; 7:592312. [PMID: 33195630 PMCID: PMC7655978 DOI: 10.3389/fvets.2020.592312] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 09/21/2020] [Indexed: 11/25/2022] Open
Abstract
Commercial poultry farms frequently use live bacterial prophylactics like vaccines and probiotics to prevent bacterial infections. Due to the emergence of antibiotic-resistant bacteria in poultry animals, a closer examination into the health benefits and limitations of commercial, live prophylactics as an alternative to antibiotics is urgently needed. In this review, we summarize the peer-reviewed literature of several commercial live bacterial vaccines and probiotics. Per our estimation, there is a paucity of peer-reviewed published research regarding these products, making repeatability, product-comparison, and understanding biological mechanisms difficult. Furthermore, we briefly-outline significant issues such as probiotic-label accuracy, lack of commercially available live bacterial vaccines for major poultry-related bacteria such as Campylobacter and Clostridium perfringens, as well research gaps (i.e., probiotic-mediated vaccine adjuvancy, gut-brain-microbiota axis). Increased emphasis on these areas would open several avenues for research, ranging from improving protection against bacterial pathogens to using these prophylactics to modulate animal behavior.
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Affiliation(s)
- Graham A. J. Redweik
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA, United States
- Interdepartmental Microbiology Graduate Program, Iowa State University, Ames, IA, United States
| | - Jared Jochum
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA, United States
- Interdepartmental Microbiology Graduate Program, Iowa State University, Ames, IA, United States
| | - Melha Mellata
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA, United States
- Interdepartmental Microbiology Graduate Program, Iowa State University, Ames, IA, United States
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6
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Phenotypes, transcriptome, and novel biofilm formation associated with the ydcI gene. Antonie Van Leeuwenhoek 2020; 113:1109-1122. [PMID: 32419108 DOI: 10.1007/s10482-020-01412-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 04/02/2020] [Indexed: 10/24/2022]
Abstract
The ydcI gene has previously been shown to encode a DNA-binding protein involved with acid stress resistance and induced biofilm formation in a strain of Salmonella enterica serovar Typhimurium. In addition, characterisation of the ydcI gene in Escherichia coli and other bacteria demonstrated strikingly different tolerance for induced ydcI expression across Gram negative species. In this report, we investigated the conservation of these phenotypes across multiple strains of S. Typhimurium and E. coli, and we used RNA Seq to identify the transcriptome of the ΔydcI mutant compared to WT in S. Typhimurium and E. coli (to establish the YdcI regulon in each species). We constructed deletion mutants in each species based on the RNA Seq results and tested these mutants for the relevant ydcI-related phenotypes. Though no evidence for a role in these phenotypes was found via the RNA Seq deletion mutants, we found that the ydcI-induced biofilm in S. Typhimurium is formed independently of the major biofilm genes csgA and bcsA indicating a potentially novel type of biofilm formation.
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7
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Felgner S, Spöring I, Pawar V, Kocijancic D, Preusse M, Falk C, Rohde M, Häussler S, Weiss S, Erhardt M. The immunogenic potential of bacterial flagella for Salmonella-mediated tumor therapy. Int J Cancer 2020; 147:448-460. [PMID: 31755108 DOI: 10.1002/ijc.32807] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 11/07/2019] [Accepted: 11/12/2019] [Indexed: 01/07/2023]
Abstract
Genetically engineered Salmonella Typhimurium are potent vectors for prophylactic and therapeutic measures against pathogens as well as cancer. This is based on the potent adjuvanticity that supports strong immune responses. The physiology of Salmonella is well understood. It simplifies engineering of both enhanced immune-stimulatory properties as well as safety features, thus, resulting in an appropriate balance between attenuation and efficacy for clinical applications. A major virulence factor of Salmonella is the flagellum. It is also a strong pathogen-associated molecular pattern recognized by extracellular and intracellular receptors of immune cells of the host. At the same time, it represents a serious metabolic burden. Accordingly, the bacteria evolved tight regulatory mechanisms that control flagella synthesis in vivo. Here, we systematically investigated the immunogenicity and adjuvant properties of various flagella mutants of Salmonella in vitro and in a mouse cancer model in vivo. We found that mutants lacking the flagellum-specific ATPase FliHIJ or the inner membrane ring FliF displayed the greatest stimulatory capacity and strongest antitumor effects, while remaining safe in vivo. Scanning electron microscopy revealed the presence of outer membrane vesicles in the ΔfliF and ΔfliHIJ mutants. Finally, the combination of the ΔfliF and ΔfliHIJ mutations with our previously described attenuated and immunogenic background strain SF102 displayed strong efficacy against the highly resistant cancer cell line RenCa. We thus conclude that manipulating flagella biosynthesis has great potential for the construction of highly efficacious and versatile Salmonella vector strains.
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Affiliation(s)
- Sebastian Felgner
- Infection Biology of Salmonella, Helmholtz Centre for Infection Research, Braunschweig, Germany.,Department of Molecular Bacteriology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Imke Spöring
- Infection Biology of Salmonella, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Vinay Pawar
- Department of Molecular Bacteriology, Helmholtz Centre for Infection Research, Braunschweig, Germany.,Central Facilities for Microscopy, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Dino Kocijancic
- Institute of Immunology, Medical School Hannover, Hannover, Germany
| | - Matthias Preusse
- Department of Molecular Bacteriology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Christine Falk
- Institute of Transplant Immunology, Medical School Hannover, Hannover, Germany
| | - Manfred Rohde
- Central Facilities for Microscopy, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Susanne Häussler
- Department of Molecular Bacteriology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Siegfried Weiss
- Institute of Immunology, Medical School Hannover, Hannover, Germany
| | - Marc Erhardt
- Infection Biology of Salmonella, Helmholtz Centre for Infection Research, Braunschweig, Germany.,Institute for Biology, Humboldt-Universität zu Berlin, Berlin, Germany
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8
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Sanapala S, Mosca L, Wang S, Curtiss R. Comparative evaluation of Salmonella Typhimurium vaccines derived from UK-1 and 14028S: Importance of inherent virulence. PLoS One 2018; 13:e0203526. [PMID: 30192849 PMCID: PMC6130210 DOI: 10.1371/journal.pone.0203526] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 08/22/2018] [Indexed: 11/18/2022] Open
Abstract
The initial virulence and invasiveness of a bacterial strain may play an important role in leading to a maximally efficacious attenuated live vaccine. Here we show that χ9909, derived from Salmonella Typhimurium UK-1 χ3761 (the most virulent S. Typhimurium strain known to us), is effective in protecting mice against lethal UK-1 and 14028S (less virulent S. Typhimurium strain) challenge. As opposed to this, 14028S-derived vaccine χ12359 induces suboptimal levels of protection, with survival percentages that are significantly lower when challenged with lethal UK-1 challenge doses. T-cell assays have revealed that significantly greater levels of Th1 cytokines IFN-γ and TNF-α were secreted by stimulated T-lymphocytes obtained from UK-1(ΔaroA) immunized mice than those from mice immunized with 14028S(ΔaroA). In addition, UK-1(ΔaroA) showed markedly higher colonizing ability in the spleen, liver, and cecum when compared to 14028S(ΔaroA). Enumeration of bacteria in fecal pellets has also revealed that UK-1(ΔaroA) can persist in the host for over 10 days whereas 14028S(ΔaroA) titers dropped significantly by day 10. Moreover, co-infection of parent strains UK-1 and 14028S resulted in considerably greater recovery of the former in multiple mucosal and gut associated lymphatic tissues. Mice immunized with UK-1(ΔaroA) were also able to clear UK-1 infection remarkably more efficiently from the target organs than 14028S(ΔaroA). Together, these results provide ample evidence to support the hypothesis that attenuated derivatives of parent strains with higher initial virulence make better vaccines.
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Affiliation(s)
- Shilpa Sanapala
- Department of Infectious Disease and Immunology, College of Veterinary Medicine, University of Florida, Gainesville, Florida, United States of America
| | - Leandra Mosca
- Department of Infectious Disease and Immunology, College of Veterinary Medicine, University of Florida, Gainesville, Florida, United States of America
| | - Shifeng Wang
- Department of Infectious Disease and Immunology, College of Veterinary Medicine, University of Florida, Gainesville, Florida, United States of America
| | - Roy Curtiss
- Department of Infectious Disease and Immunology, College of Veterinary Medicine, University of Florida, Gainesville, Florida, United States of America
- * E-mail:
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9
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Panzenhagen PHN, Cabral CC, Suffys PN, Franco RM, Rodrigues DP, Conte-Junior CA. Comparative genome analysis and characterization of the Salmonella Typhimurium strain CCRJ_26 isolated from swine carcasses using whole-genome sequencing approach. Lett Appl Microbiol 2018; 66:352-359. [PMID: 29397031 DOI: 10.1111/lam.12859] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 01/11/2018] [Accepted: 01/20/2018] [Indexed: 02/03/2023]
Abstract
Salmonella pathogenicity relies on virulence factors many of which are clustered within the Salmonella pathogenicity islands. Salmonella also harbours mobile genetic elements such as virulence plasmids, prophage-like elements and antimicrobial resistance genes which can contribute to increase its pathogenicity. Here, we have genetically characterized a selected S. Typhimurium strain (CCRJ_26) from our previous study with Multiple Drugs Resistant profile and high-frequency PFGE clonal profile which apparently persists in the pork production centre of Rio de Janeiro State, Brazil. By whole-genome sequencing, we described the strain's genome virulent content and characterized the repertoire of bacterial plasmids, antibiotic resistance genes and prophage-like elements. Here, we have shown evidence that strain CCRJ_26 genome possible represent a virulence-associated phenotype which may be potentially virulent in human infection. SIGNIFICANCE AND IMPACT OF THE STUDY Whole-genome sequencing technologies are still costly and remain underexplored for applied microbiology in Brazil. Hence, this genomic description of S. Typhimurium strain CCRJ_26 will provide help in future molecular epidemiological studies. The analysis described here reveals a quick and useful pipeline for bacterial virulence characterization using whole-genome sequencing approach.
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Affiliation(s)
- P H N Panzenhagen
- Food Science Program, Chemistry Institute, University Federal of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil.,Department of Food Technology, Faculty of Veterinary Medicine, Federal Fluminense University (UFF), Niterói, Rio de Janeiro, Brazil
| | - C C Cabral
- Department of Food Technology, Faculty of Veterinary Medicine, Federal Fluminense University (UFF), Niterói, Rio de Janeiro, Brazil.,Faculty of Veterinary Medicine, Severino Sombra University (USS), Vassouras, Rio de Janeiro, Brazil
| | - P N Suffys
- Laboratory of Molecular Biology and Diagnosis of Infectious Diseases, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - R M Franco
- Department of Food Technology, Faculty of Veterinary Medicine, Federal Fluminense University (UFF), Niterói, Rio de Janeiro, Brazil
| | - D P Rodrigues
- National Reference Laboratory Diagnosis of Enteric Bacteria, Oswaldo Cruz Institute, Rio de Janeiro, Brazil
| | - C A Conte-Junior
- Food Science Program, Chemistry Institute, University Federal of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil.,Department of Food Technology, Faculty of Veterinary Medicine, Federal Fluminense University (UFF), Niterói, Rio de Janeiro, Brazil.,National Institute of Quality Control in Health, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
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10
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Maddux JT, Stromberg ZR, Curtiss Iii R, Mellata M. Evaluation of Recombinant Attenuated Salmonella Vaccine Strains for Broad Protection against Extraintestinal Pathogenic Escherichia coli. Front Immunol 2017; 8:1280. [PMID: 29062318 PMCID: PMC5640888 DOI: 10.3389/fimmu.2017.01280] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 09/25/2017] [Indexed: 01/21/2023] Open
Abstract
Antibiotic-resistant bacterial infections are difficult to treat, producing a burden on healthcare and the economy. Extraintestinal pathogenic Escherichia coli (ExPEC) strains frequently carry antibiotic resistance genes, cause infections outside of the intestine, and are causative agents of hospital-acquired infections. Developing a prevention strategy against this pathogen is challenging due to its antibiotic resistance and antigenic diversity. E. coli common pilus (ECP) is frequently found in ExPEC strains and may serve as a common antigen to induce protection against several ExPEC serotypes. In addition, live recombinant attenuated Salmonella vaccine (RASV) strains have been used to prevent Salmonella infection and can also be modified to deliver foreign antigens. Thus, the objective of this study was to design a RASV to produce ECP on its surface and assess its ability to provide protection against ExPEC infections. To constitutively display ECP in a RASV strain, we genetically engineered a vector (pYA4428) containing aspartate-β-semialdehyde dehydrogenase and E. coli ecp genes and introduced it into RASV χ9558. RASV χ9558 containing an empty vector (pYA3337) was used as a control to assess protection conferred by the RASV strain without ECP. We assessed vaccine efficacy in in vitro bacterial inhibition assays and mouse models of ExPEC-associated human infections. We found that RASV χ9558(pYA4428) synthesized the major pilin (EcpA) and tip pilus adhesin (EcpD) on the bacterial surface. Mice orally vaccinated with RASV χ9558(pYA3337) without ECP or χ9558(pYA4428) with ECP, produced anti-Salmonella LPS and anti-E. coli EcpA and EcpD IgG and IgA antibodies. RASV strains showed protective potential against some E. coli and Salmonella strains as assessed using in vitro assays. In mouse sepsis and urinary tract infection challenge models, both vaccines had significant protection in some internal organs. Overall, this work showed that RASVs can elicit an immune response to E. coli and Salmonella antigens in some mice, provide significant protection in some internal organs during ExPEC challenge, and thus this study is a promising initial step toward developing a vaccine for prevention of ExPEC infections. Future studies should optimize the ExPEC antigens displayed by the RASV strain for a more robust immune response and enhanced protection against ExPEC infection.
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Affiliation(s)
- Jacob T Maddux
- The Biodesign Institute, Arizona State University, Tempe, AZ, United States
| | - Zachary R Stromberg
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA, United States
| | - Roy Curtiss Iii
- The Biodesign Institute, Arizona State University, Tempe, AZ, United States.,School of Life Sciences, Arizona State University, Tempe, AZ, United States
| | - Melha Mellata
- The Biodesign Institute, Arizona State University, Tempe, AZ, United States.,Department of Food Science and Human Nutrition, Iowa State University, Ames, IA, United States
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11
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Whole-Genome Sequencing Identifies In Vivo Acquisition of a blaCTX-M-27-Carrying IncFII Transmissible Plasmid as the Cause of Ceftriaxone Treatment Failure for an Invasive Salmonella enterica Serovar Typhimurium Infection. Antimicrob Agents Chemother 2016; 60:7224-7235. [PMID: 27671066 DOI: 10.1128/aac.01649-16] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 09/12/2016] [Indexed: 12/11/2022] Open
Abstract
We report a case of ceftriaxone treatment failure for bacteremia caused by Salmonella enterica subsp. enterica serovar Typhimurium, due to the in vivo acquisition of a blaCTX-M-27-encoding IncFII group transmissible plasmid. The original β-lactamase-susceptible isolate ST882S was replaced by the resistant isolate ST931R during ceftriaxone treatment. After relapse, treatment was changed to ciprofloxacin, and the patient recovered. Isolate ST931R could transfer resistance to Escherichia coli at 37°C. We used whole-genome sequencing of ST882S and ST931R, the E. coli transconjugant, and isolated plasmid DNA to unequivocally show that ST882S and ST931R had identical chromosomes, both having 206 identical single-nucleotide polymorphisms (SNPs) versus S Typhimurium 14028s. We assembled a complete circular genome for ST931R, to which ST882S reads mapped with no SNPs. ST882S and ST931R were isogenic except for the presence of three additional plasmids in ST931R. ST931R and the E. coli transconjugant were ceftriaxone resistant due to the presence of a 60.5-kb IS26-flanked, blaCTX-M-27-encoding IncFII plasmid. Compared to 14082s, ST931R has almost identical Gifsy-1, Gifsy-2, and ST64B prophages, lacks Gifsy-3, and instead carries a unique Fels-2 prophage related to that found in LT2. ST882S and ST931R both had a 94-kb virulence plasmid showing >99% identity with pSLT14028s and a cryptic 3,904-bp replicon; ST931R also has cryptic 93-kb IncI1 and 62-kb IncI2 group plasmids. To the best of our knowledge, in vivo acquisition of extended-spectrum β-lactamase resistance by S Typhimurium and blaCTX-M-27 genes in U.S. isolates of Salmonella have not previously been reported.
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12
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Corrected Genome Annotations Reveal Gene Loss and Antibiotic Resistance as Drivers in the Fitness Evolution of Salmonella enterica Serovar Typhimurium. J Bacteriol 2016; 198:3152-3161. [PMID: 27621280 DOI: 10.1128/jb.00545-16] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 09/02/2016] [Indexed: 11/20/2022] Open
Abstract
Horizontal acquisition of novel chromosomal genes is considered to be a key process in the evolution of bacterial pathogens. However, the identification of gene presence or absence could be hindered by the inconsistencies in bacterial genome annotations. Here, we performed a cross-annotation of omnipresent core and mosaic accessory genes in the chromosome of Salmonella enterica serovar Typhimurium across a total of 20 fully assembled genomes deposited into GenBank. Cross-annotation resulted in a 32% increase in the number of core genes and a 3-fold decrease in the number of genes identified as mosaic genes (i.e., genes present in some strains only) by the original annotation. Of the remaining noncore genes, the vast majority were prophage genes, and 255 of the nonphage genes were actually of core origin but lost in some strains upon the emergence of the S Typhimurium serovar, suggesting that the chromosomal portion of the S Typhimurium genome acquired a very limited number of novel genes other than prophages. Only horizontally acquired nonphage genes related to bacterial fitness or virulence were found in four recently sequenced isolates, all located on three different genomic islands that harbor multidrug resistance determinants. Thus, the extensive use of antimicrobials could be the main selection force behind the new fitness gene acquisition and the emergence of novel Salmonella pathotypes. IMPORTANCE Significant discrepancies in the annotations of bacterial genomes could mislead the conclusions about evolutionary origin of chromosomal genes, as we demonstrate here via a cross-annotation-based analysis of Salmonella Typhimurium genomes from GenBank. We conclude that despite being able to infect a broad range of vertebrate hosts, the genomic diversity of S Typhimurium strains is almost exclusively limited to gene loss and the transfer of prophage DNA. Only nonphage chromosomal genes acquired after the emergence of the serovar are linked to the genomic islands harboring multidrug resistance factors. Since the fitness factors could lead to increased virulence, this poses an important research question: could overuse or misuse of antimicrobials act as selection forces for the emergence of more pathogenic strains of Salmonella?
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13
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Liu Q, Liu Q, Yi J, Liang K, Hu B, Zhang X, Curtiss R, Kong Q. Outer membrane vesicles from flagellin-deficient Salmonella enterica serovar Typhimurium induce cross-reactive immunity and provide cross-protection against heterologous Salmonella challenge. Sci Rep 2016; 6:34776. [PMID: 27698383 PMCID: PMC5048178 DOI: 10.1038/srep34776] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 09/16/2016] [Indexed: 01/12/2023] Open
Abstract
Outer membrane vesicles (OMVs) isolated from Salmonella Typhimurium are potentially useful for developing subunit vaccines because of high immunogenicity and protective efficacy. However, flagella might remain in OMV pellets following OMV purification, resulting in non-essential immune responses and counteraction of bacterial protective immune responses when developing a vaccine against infection of multiple serotypes Salmonella. In this study, a flagellin-deficient S. Typhimurium mutant was constructed. Lipopolysaccharide profiles, protein profiles and cryo-electron microscopy revealed that there were no significant differences between the wild-type and mutant OMVs, with the exception of a large amount of flagellin in the wild-type OMVs. Neither the wild-type OMVs nor the non-flagellin OMVs were toxic to macrophages. Mice immunized with the non-flagellin OMVs produced high concentrations of IgG. The non-flagellin OMVs elicited strong mucosal antibody responses in mice when administered via the intranasal route in addition to provoking higher cross-reactive immune responses against OMPs isolated from S. Choleraesuis and S. Enteritidis. Both intranasal and intraperitoneal immunization with the non-flagellin OMVs provided efficient protection against heterologous S. Choleraesuis and S. Enteritidis challenge. Our results indicate that the flagellin-deficient OMVs may represent a new vaccine platform that could be exploited to facilitate the production of a broadly protective vaccine.
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Affiliation(s)
- Qiong Liu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, China.,Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, AZ, 85287-5401, USA.,Department of Medical Microbiology, School of Medicine, Nanchang University, Nanchang, 330006, China
| | - Qing Liu
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, China
| | - Jie Yi
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, China
| | - Kang Liang
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, China
| | - Bo Hu
- Department of Pathology and Laboratory Medicine, University of Texas Medical School at Houston, Houston, TX, 77030, USA
| | - Xiangmin Zhang
- Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy/Health Sciences, Wayne State University, Detroit, MI, 48202, USA
| | - Roy Curtiss
- Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, AZ, 85287-5401, USA
| | - Qingke Kong
- Institute of Preventive Veterinary Medicine, Sichuan Agricultural University, Chengdu, 611130, China.,Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, AZ, 85287-5401, USA
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14
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Genomic Analysis of Salmonella enterica Serovar Typhimurium Characterizes Strain Diversity for Recent U.S. Salmonellosis Cases and Identifies Mutations Linked to Loss of Fitness under Nitrosative and Oxidative Stress. mBio 2016; 7:e00154. [PMID: 26956590 PMCID: PMC4810482 DOI: 10.1128/mbio.00154-16] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Salmonella enterica serovar Typhimurium is one of the most common S. enterica serovars associated with U.S. foodborne outbreaks. S. Typhimurium bacteria isolated from humans exhibit wide-ranging virulence phenotypes in inbred mice, leading to speculation that some strains are more virulent in nature. However, it is unclear whether increased virulence in humans is related to organism characteristics or initial treatment failure due to antibiotic resistance. Strain diversity and genetic factors contributing to differential human pathogenicity remain poorly understood. We reconstructed phylogeny, resolved genetic population structure, determined gene content and nucleotide variants, and conducted targeted phenotyping assays for S. Typhimurium strains collected between 1946 and 2012 from humans and animals in the United States and abroad. Strains from recent U.S. salmonellosis cases were associated with five S. Typhimurium lineages distributed within three phylogenetic clades, which are not restricted by geography, year of acquisition, or host. Notably, two U.S. strains and four Mexican strains are more closely related to strains associated with human immunodeficiency virus (HIV)-infected individuals in sub-Saharan Africa than to other North American strains. Phenotyping studies linked variants specific to these strains in hmpA and katE to loss of fitness under nitrosative and oxidative stress, respectively. These results suggest that U.S. salmonellosis is caused by diverse S. Typhimurium strains circulating worldwide. One lineage has mutations in genes affecting fitness related to innate immune system strategies for fighting pathogens and may be adapting to immunocompromised humans by a reduction in virulence capability, possibly due to a lack of selection for its maintenance as a result of the worldwide HIV epidemic. Nontyphoidal Salmonella bacteria cause an estimated 1.2 million illnesses annually in the United States, 80 million globally, due to ingestion of contaminated food or water. Salmonella Typhimurium is one of the most common serovars associated with foodborne illness, causing self-limiting gastroenteritis and, in approximately 5% of infected patients, systemic infection. Although some S. Typhimurium strains are speculated to be more virulent than others, it is unknown how strain diversity and genetic factors contribute to differential human pathogenicity. Ours is the first study to examine the diversity of S. Typhimurium associated with recent cases of U.S. salmonellosis and to provide some initial correlation between observed genotypes and phenotypes. Definition of specific S. Typhimurium lineages based on such phenotype/genotype correlations may identify strains with greater capability of associating with specific food sources, allowing outbreaks to be more quickly identified. Additionally, defining simple correlates of pathogenesis may have predictive value for patient outcome.
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15
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Felgner S, Kocijancic D, Frahm M, Curtiss R, Erhardt M, Weiss S. Optimizing Salmonella enterica serovar Typhimurium for bacteria-mediated tumor therapy. Gut Microbes 2016; 7:171-7. [PMID: 26939530 PMCID: PMC4856459 DOI: 10.1080/19490976.2016.1155021] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Bacteria-mediated tumor therapy using Salmonella enterica serovar Typhimurium is a therapeutic option with great potential. Numerous studies explored the potential of Salmonella Typhimurium for therapeutic applications, however reconciling safety with vectorial efficacy remains a major issue. Recently we have described a conditionally attenuated Salmonella vector that is based on genetic lipopolysaccharide modification. This vector combines strong attenuation with appropriate anti-tumor properties by targeting various cancerous tissues in vivo. Therefore, it was promoted as an anti-tumor agent. In this addendum, we summarize these findings and demonstrate additional optimization steps that may further improve the therapeutic efficacy of our vector strain.
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Affiliation(s)
- Sebastian Felgner
- Department of Molecular Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Dino Kocijancic
- Department of Molecular Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Michael Frahm
- Department of Molecular Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Roy Curtiss
- Department of Infectious Diseases and Pathology, University of Florida, Gainesville, USA
| | - Marc Erhardt
- Junior Research Group Infection Biology of Salmonella, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Siegfried Weiss
- Department of Molecular Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany,Institute of Immunology, Medical School Hannover, Hannover, Germany
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16
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Mohammed M, Cormican M. Whole genome sequencing provides possible explanations for the difference in phage susceptibility among two Salmonella Typhimurium phage types (DT8 and DT30) associated with a single foodborne outbreak. BMC Res Notes 2015; 8:728. [PMID: 26613761 PMCID: PMC4661946 DOI: 10.1186/s13104-015-1687-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 11/10/2015] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Phage typing has been used for decades as a rapid, low cost approach for the epidemiological surveillance of Salmonella enterica subsp. enterica serovar Typhimurium. Although molecular methods are replacing phage typing the system is still in use and provides a valuable model for study of phage-host interaction. Phage typing depends on the pattern of bacterial resistance or sensitivity to a panel of specific bacteriophages. In the phage typing scheme, S. Typhimurium definitive phage types (DT) 8 and 30 differ greatly in their susceptibility to the 30 typing phages of S. Typhimurium; DT8 is susceptible to 11 phages whereas DT30 is resistant to all typing phages except one phage although both DT8 and DT30 were reported to be associated with a single foodborne salmonellosis outbreak in Ireland between 2009 and 2011. We wished to study the genomic correlates of the DT8 and DT30 difference in phage susceptibility using the whole genome sequence (WGS) of S. Typhimurium DT8 and DT30 representatives. RESULTS Comparative genome analysis revealed that both S. Typhimurium DT8 and DT30 are lysogenic for three prophages including two S. Typhimurium associated prophages (Gifsy-2 and ST64B) and one S. Enteritidis associated prophage (Enteritidis lysogenic phage S) which has not been detected previously in S. Typhimurium. Furthermore, DT8 and DT30 contain identical clustered regularly interspaced short palindromic repeats (CRISPRs). Interestingly, S. Typhimurium DT8 harbours an accessory genome represented by a virulence plasmid that is highly related to the pSLT plasmid of S. Typhimurium strain LT2 (phage typed as DT4) and codes a unique methyltransferase (MTase); M.EcoGIX related MTase. This plasmid is not detected in DT30. On the other hand, DT30 carries a unique genomic island similar to the integrative and conjugative element (ICE) of Enterotoxigenic Escherichia coli (ETEC) and encodes type IV secretion pathway system (T4SS) and several hypothetical proteins. This genomic island is not detected in DT8. CONCLUSIONS We suggest that differences in phage susceptibility between DT8 and DT30 may be related to acquisition of ICE in DT30 and loss of pSLT like plasmid that might be associated with DT30 resistance to almost all phages used in the typing scheme. Additional studies are required to determine the significance of the differences among DT8 and DT30 in relation to the difference in phage susceptibility. This study represents an initial step toward understanding the molecular basis of this host-phage relationship.
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Affiliation(s)
- Manal Mohammed
- School of Medicine, National University of Ireland Galway, Galway, Ireland.
| | - Martin Cormican
- School of Medicine, National University of Ireland Galway, Galway, Ireland.
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17
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Application of Molecular Approaches for Understanding Foodborne Salmonella Establishment in Poultry Production. ACTA ACUST UNITED AC 2014. [DOI: 10.1155/2014/813275] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Salmonellosis in the United States is one of the most costly foodborne diseases. Given that Salmonella can originate from a wide variety of environments, reduction of this organism at all stages of poultry production is critical. Salmonella species can encounter various environmental stress conditions which can dramatically influence their survival and colonization. Current knowledge of Salmonella species metabolism and physiology in relation to colonization is traditionally based on studies conducted primarily with tissue culture and animal infection models. Consequently, while there is some information about environmental signals that control Salmonella growth and colonization, much still remains unknown. Genetic tools for comprehensive functional genomic analysis of Salmonella offer new opportunities for not only achieving a better understanding of Salmonella pathogens but also designing more effective intervention strategies. Now the function(s) of each single gene in the Salmonella genome can be directly assessed and previously unknown genetic factors that are required for Salmonella growth and survival in the poultry production cycle can be elucidated. In particular, delineating the host-pathogen relationships involving Salmonella is becoming very helpful for identifying optimal targeted gene mutagenesis strategies to generate improved vaccine strains. This represents an opportunity for development of novel vaccine approaches for limiting Salmonella establishment in early phases of poultry production. In this review, an overview of Salmonella issues in poultry, a general description of functional genomic technologies, and their specific application to poultry vaccine developments are discussed.
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18
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Effect of egg washing and correlation between eggshell characteristics and egg penetration by various Salmonella Typhimurium strains. PLoS One 2014; 9:e90987. [PMID: 24621821 PMCID: PMC3951326 DOI: 10.1371/journal.pone.0090987] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 02/06/2014] [Indexed: 11/19/2022] Open
Abstract
Salmonella is an important foodborne pathogen, causing an estimated 11,992 cases of infection in Australia per year. Egg or egg product related salmonellosis is a major concern for the egg industry. Worldwide, S. Typhimurium is one of the most common serovars identified in Salmonella food poisoning cases. The current study investigated the ability of five S. Typhimurium strains to penetrate washed and unwashed eggs using whole egg and agar egg penetration methods. All S. Typhimurium strains were able to penetrate eggshells and survive in egg albumen (at 20°C) according to whole egg penetration results. Polymerase Chain Reaction results demonstrated that S. Typhimurium strain 2 (103 and 105 CFU/mL), and strain 5 (103 and 105 CFU/mL) egg penetration was significantly higher (p<0.05) in washed eggs when compared to unwashed eggs. Statistical analysis of the agar penetration experiment indicated that S. Typhimurium was able to penetrate washed eggs at a significantly higher rate when compared to unwashed eggs (p<0.05). When compared to unwashed eggs, washed eggs also had significantly damaged cuticles. Statistical analysis also indicated that eggshell penetration by S. Typhimurium was related to various eggshell ultrastructural features such as cap quality, alignment, erosion, confluence, Type B bodies and cuticle cover.
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19
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Hiley L, Fang NX, Micalizzi GR, Bates J. Distribution of Gifsy-3 and of variants of ST64B and Gifsy-1 prophages amongst Salmonella enterica Serovar Typhimurium isolates: evidence that combinations of prophages promote clonality. PLoS One 2014; 9:e86203. [PMID: 24475087 PMCID: PMC3901673 DOI: 10.1371/journal.pone.0086203] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Accepted: 12/08/2013] [Indexed: 11/19/2022] Open
Abstract
Salmonella isolates harbour a range of resident prophages which can influence their virulence and ability to compete and survive in their environment. Phage gene profiling of a range of phage types of Salmonella enterica subsp. enterica serovar Typhimurium (S. Typhimurium) indicates a significant level of correlation of phage gene profile with phage type as well as correlation with genotypes determined by a combination of multi-locus variable-number tandem repeat (VNTR) typing and clustered regularly interspaced short palindromic repeats (CRISPR) typing. Variation in phage gene profiles appears to be partly linked to differences in composition of variants of known prophages. We therefore conducted a study of the distribution of variants of ST64B and Gifsy-1 prophages and coincidently the presence of Gifsy-3 prophage in a range of S. Typhimurium phage types and genotypes. We have discovered two variants of the DT104 variant of ST64B and at least two new variants of Gifsy-1 as well as variants of related phage genes. While there is definite correlation between phage type and the prophage profile based on ST64B and Gifsy-1 variants we find stronger correlation between the VNTR/CRISPR genotype and prophage profile. Further differentiation of some genotypes is obtained by addition of the distribution of Gifsy-3 and a sequence variant of the substituted SB26 gene from the DT104 variant of ST64B. To explain the correlation between genotype and prophage profile we propose that suites of resident prophages promote clonality possibly through superinfection exclusion systems.
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Affiliation(s)
- Lester Hiley
- Public Health Microbiology Laboratory, Forensic and Scientific Services, Queensland Department of Health, Brisbane, Queensland, Australia
- * E-mail:
| | - Ning-Xia Fang
- Public Health Microbiology Laboratory, Forensic and Scientific Services, Queensland Department of Health, Brisbane, Queensland, Australia
| | - Gino R. Micalizzi
- Public Health Microbiology Laboratory, Forensic and Scientific Services, Queensland Department of Health, Brisbane, Queensland, Australia
| | - John Bates
- Public Health Microbiology Laboratory, Forensic and Scientific Services, Queensland Department of Health, Brisbane, Queensland, Australia
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20
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Rosenkrantz JT, Aarts H, Abee T, Rolfe MD, Knudsen GM, Nielsen MB, Thomsen LE, Zwietering MH, Olsen JE, Pin C. Non-essential genes form the hubs of genome scale protein function and environmental gene expression networks in Salmonella enterica serovar Typhimurium. BMC Microbiol 2013; 13:294. [PMID: 24345035 PMCID: PMC3878590 DOI: 10.1186/1471-2180-13-294] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 12/10/2013] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Salmonella Typhimurium is an important pathogen of human and animals. It shows a broad growth range and survives in harsh conditions. The aim of this study was to analyze transcriptional responses to a number of growth and stress conditions as well as the relationship of metabolic pathways and/or cell functions at the genome-scale-level by network analysis, and further to explore whether highly connected genes (hubs) in these networks were essential for growth, stress adaptation and virulence. RESULTS De novo generated as well as published transcriptional data for 425 selected genes under a number of growth and stress conditions were used to construct a bipartite network connecting culture conditions and significantly regulated genes (transcriptional network). Also, a genome scale network was constructed for strain LT2. The latter connected genes with metabolic pathways and cellular functions. Both networks were shown to belong to the family of scale-free networks characterized by the presence of highly connected nodes or hubs which are genes whose transcription is regulated when responding to many of the assayed culture conditions or genes encoding products involved in a high number of metabolic pathways and cell functions.The five genes with most connections in the transcriptional network (wraB, ygaU, uspA, cbpA and osmC) and in the genome scale network (ychN, siiF (STM4262), yajD, ybeB and dcoC) were selected for mutations, however mutagenesis of ygaU and ybeB proved unsuccessful. No difference between mutants and the wild type strain was observed during growth at unfavorable temperatures, pH values, NaCl concentrations and in the presence of H2O2. Eight mutants were evaluated for virulence in C57/BL6 mice and none differed from the wild type strain. Notably, however, deviations of phenotypes with respect to the wild type were observed when combinations of these genes were deleted. CONCLUSION Network analysis revealed the presence of hubs in both transcriptional and functional networks of S. Typhimurium. Hubs theoretically confer higher resistance to random mutation but a greater susceptibility to directed attacks, however, we found that genes that formed hubs were dispensable for growth, stress adaptation and virulence, suggesting that evolution favors non-essential genes as main connectors in cellular networks.
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Affiliation(s)
- Jesper T Rosenkrantz
- Department of Veterinary Disease Biology, University of Copenhagen, Stigbøjlen 4, 1870 Frederiksberg, C, Denmark
| | - Henk Aarts
- Centre for Infectious disease control, National Institute for Public Health, PO box 1, 3720 BA Bilthoven, The Netherlands
| | - Tjakko Abee
- Wageningen University and Research Centre, Laboratory of Food Microbiology, P.O. Box 17, 6700 AA Wageningen, Netherlands
| | - Matthew D Rolfe
- Institute of Food Research, Norwich Research Park, Norwich NR4 7UA, UK
| | - Gitte M Knudsen
- Institute of Food Research, Norwich Research Park, Norwich NR4 7UA, UK
- National Food Institute, Danish Technical University, Soelvtofts Plads, 2800 Kgs. Lyngby, Denmark
| | - Maj-Britt Nielsen
- Department of Veterinary Disease Biology, University of Copenhagen, Stigbøjlen 4, 1870 Frederiksberg, C, Denmark
- Present address: DANSTEM Laboratory, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen, N, Denmark
| | - Line E Thomsen
- Department of Veterinary Disease Biology, University of Copenhagen, Stigbøjlen 4, 1870 Frederiksberg, C, Denmark
| | - Marcel H Zwietering
- Wageningen University and Research Centre, Laboratory of Food Microbiology, P.O. Box 17, 6700 AA Wageningen, Netherlands
| | - John E Olsen
- Department of Veterinary Disease Biology, University of Copenhagen, Stigbøjlen 4, 1870 Frederiksberg, C, Denmark
| | - Carmen Pin
- Institute of Food Research, Norwich Research Park, Norwich NR4 7UA, UK
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21
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A naturally occurring single nucleotide polymorphism in the Salmonella SPI-2 type III effector srfH/sseI controls early extraintestinal dissemination. PLoS One 2012; 7:e45245. [PMID: 23028876 PMCID: PMC3445477 DOI: 10.1371/journal.pone.0045245] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2012] [Accepted: 08/16/2012] [Indexed: 12/20/2022] Open
Abstract
CD18 expressing phagocytes associated with the gastro-intestinal (GI) epithelium can shuttle Salmonella directly into the bloodstream within a few minutes following microbial ingestion. We have previously demonstrated that Salmonella controls the CD18 pathway to deeper tissue, manipulating the migratory properties of infected cells as an unappreciated component of its pathogenesis. We have observed that one type III effector, SrfH (also called SseI) that Salmonella secretes into infected phagocytes manipulates the host protein TRIP6 to stimulate their migration. Paradoxically, SrfH was shown in another study to subvert a different host protein, IQGAP1, in a manner that inhibits the productive motility of such cells, perhaps to avoid interactions with T cells. Here, we resolve the discrepancy. We report that one naturally occurring allele of srfH promotes the migration of infected phagocytes into the bloodstream, while another naturally occurring allele that differs by only a single nucleotide polymorphism (SNP) does not. This SNP determines if the protein contains an aspartic acid or a glycine residue at position 103 and may determine if SrfH binds TRIP6. SrfH Gly103 is a rare allele, but is present in the highly invasive strain Salmonella enterica serovar Typhimurium UK-1 (stands for universal killer). It is also present in the genome of the only sequenced strain belonging to the emerging pandemic Salmonella enterica serovar 4, [5],12,i:-, which is frequently associated with septicemia. Finally, we present evidence that suggests that Gifsy-2, the bacteriophage upon which srfH resides, is present in a clinical isolate of the human-specific pathogen, Salmonella enterica serovar Typhi. These observations may have interesting implications for our understanding of Salmonella pathogenesis.
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