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Iibushi J, Nozawa T, Toh H, Nakagawa I. ATG9B regulates bacterial internalization via actin rearrangement. iScience 2024; 27:109623. [PMID: 38706859 PMCID: PMC11066431 DOI: 10.1016/j.isci.2024.109623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 01/16/2024] [Accepted: 03/26/2024] [Indexed: 05/07/2024] Open
Abstract
Invasive bacterial pathogens are internalized by host cells through endocytosis, which is regulated by a cascade of actin rearrangement signals triggered by host cell receptors or bacterial proteins delivered into host cells. However, the molecular mechanisms that mediate actin rearrangement to promote bacterial invasion are not fully understood. Here, we show that the autophagy-related (ATG) protein ATG9B regulates the internalization of various bacteria by controlling actin rearrangement. ATG knockout screening and knockdown experiments in HeLa cells identified ATG9B as a critical factor for bacterial internalization. In particular, cells with ATG9B knockdown exhibited an accumulation of actin filaments and phosphorylated LIM kinase and cofilin, suggesting that ATG9B is involved in actin depolymerization. Furthermore, the kinase activity of Unc-51-like autophagy-activating kinase 1 was found to regulate ATG9B localization and actin remodeling. These findings revealed a newly discovered function of ATG proteins in bacterial infection rather than autophagy-mediated immunity.
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Affiliation(s)
- Junpei Iibushi
- Department of Microbiology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku 606-8501, Kyoto, Japan
| | - Takashi Nozawa
- Department of Microbiology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku 606-8501, Kyoto, Japan
| | - Hirotaka Toh
- Department of Microbiology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku 606-8501, Kyoto, Japan
| | - Ichiro Nakagawa
- Department of Microbiology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku 606-8501, Kyoto, Japan
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2
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Song Y, Sun M, Mu G, Tuo Y. Exopolysaccharide secreted by Lactiplantibacillus plantarum Y12 showed inhibitory effect on the pathogenicity of Shigella flexneri in vitro and in vivo. Int J Biol Macromol 2024; 261:129478. [PMID: 38237822 DOI: 10.1016/j.ijbiomac.2024.129478] [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: 10/09/2023] [Revised: 01/04/2024] [Accepted: 01/11/2024] [Indexed: 01/28/2024]
Abstract
Shigella flexneri is a prevalent foodborne and waterborne pathogen that threatens human health. Our previous research indicated that the Lactiplantibacillus plantarum Y12 exopolysaccharide (L-EPS) potentially inhibited the pathogenicity of S. flexneri. The in vitro results of this study demonstrated that L-EPS effectively mitigated the symptoms induced by S. flexneri in HT-29 cells, including inhibited gene expression levels of IL-1β, IL-6, IL-8, TNF-α, TLR 2/4, and NOD1/2; decreased apoptosis ratio; and alleviated damage degree of intestinal barrier function (Zona occludens 1, Occludin, and Claudin-1). The in vivo results demonstrated that S. flexneri treated with L-EPS elicited mild adverse physiological manifestations, an inflammatory response, and tissue damage. The infection of S. flexneri caused significant alterations in the abundance of phylum (Firmicutes, Bacteroidota, Actinobacteriota, and Proteobacteria), family (Lachnospiraceae, Muribaculaceae, Rikenellaceae, Prevotellaceaea, Ruminococcaceae, and Lactobaillaceae), and genus (Escherichia Shigella and Lachnospirillaceae NK4A136 group) within the cecal microbiota. These changes were accompanied by perturbations in taurine and hypotaurine metabolism, tricarboxylic acid (TCA) cycle activity, arginine biosynthesis, and histidine metabolic pathways. However, intervention with L-EPS attenuated the dysbiosis of cecal microbiota and metabolic disturbances. In summary, our research suggested a potential application of L-EPS as a functional food additive for mitigating S. flexneri infection.
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Affiliation(s)
- Yinglong Song
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, PR China
| | - Mengying Sun
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, PR China
| | - Guangqing Mu
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, PR China; Dalian Probiotics Function Research Key Laboratory, Dalian Polytechnic University, Dalian 116034, PR China.
| | - Yanfeng Tuo
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, PR China.
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3
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Salehi S, Allahverdy J, Pourjafar H, Sarabandi K, Jafari SM. Gut Microbiota and Polycystic Ovary Syndrome (PCOS): Understanding the Pathogenesis and the Role of Probiotics as a Therapeutic Strategy. Probiotics Antimicrob Proteins 2024:10.1007/s12602-024-10223-5. [PMID: 38421576 DOI: 10.1007/s12602-024-10223-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/22/2024] [Indexed: 03/02/2024]
Abstract
Polycystic ovary syndrome (PCOS) is one of the most common disorders among women in modern societies. A variety of factors can contribute to the development of PCOS. These women often exhibit high insulin resistance (IR), hyperandrogenism, irregular periods, and infertility. Dysbiosis of the gut microbiota (GMB) in women with PCOS has attracted the attention of many researchers. Porphyromonas spp., B. coprophilus, and F. prausnitzii are found in higher numbers in the gut of women with PCOS. Short-chain fatty acids (SCFAs), produced by the intestinal microbiota through fermentation, play an essential role in regulating metabolic activities and are helpful in reducing insulin resistance and improving PCOS symptoms. According to studies, the bacteria producing SCFAs in the gut of these women are less abundant than in healthy women. The effectiveness of using probiotic supplements has been proven to improve the condition of women with PCOS. Daily consumption of probiotics improves dysbiosis of the intestinal microbiome and increases the production of SCFAs.
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Affiliation(s)
- Samaneh Salehi
- Department of Food Biotechnology, Faculty of Agriculture, University of Tabriz, Tabriz, Iran
| | - Javad Allahverdy
- Department of Medical Laboratory Sciences, Faculty of Allied Medicine, Iran University of Medical Sciences, Tehran, Iran
- Students' Research Committee, Faculty of Allied Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Hadi Pourjafar
- Dietary Supplements and Probiotic Research Center, Alborz University of Medical Sciences, Karaj, Iran
| | - Khashayar Sarabandi
- Research Institute of Food Science and Technology (RIFST), Km 12 Mashhad-Quchan Highway, PO Box 91895, Mashhad, 157-356, Iran
| | - Seid Mahdi Jafari
- Department of Food Materials and Process Design Engineering, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran.
- Halal Research Center of IRI, Iran Food and Drug Administration, Ministry of Health and Medical Education, Tehran, Iran.
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4
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Perruzza L, Zagaglia C, Vitiello L, Sarshar M, Strati F, Pasqua M, Grassi F, Nicoletti M, Palamara AT, Ambrosi C, Scribano D. The Shigella flexneri virulence factor apyrase is released inside eukaryotic cells to hijack host cell fate. Microbiol Spectr 2023; 11:e0077523. [PMID: 37795996 PMCID: PMC10714728 DOI: 10.1128/spectrum.00775-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 08/19/2023] [Indexed: 10/06/2023] Open
Abstract
IMPORTANCE In this paper, we demonstrated that apyrase is released within the host cell cytoplasm during infection to target the intracellular ATP pool. By degrading intracellular ATP, apyrase contributes to prevent caspases activation, thereby inhibiting the activation of pyroptosis in infected cells. Our results show, for the first time, that apyrase is involved in the modulation of host cell survival, thereby aiding this pathogen to dampen the inflammatory response. This work adds a further piece to the puzzle of Shigella pathogenesis. Due to its increased spread worldwide, prevention and controlling strategies are urgently needed. Overall, this study highlighted apyrase as a suitable target for an anti-virulence therapy to tackle this pathogen.
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Affiliation(s)
- Lisa Perruzza
- Institute for Research in Biomedicine, Faculty of Biomedical Sciences, Università della Svizzera Italiana, Bellinzona, Switzerland
- Humabs BioMed, a subsidiary of Vir Biotechnology, Bellinzona, Switzerland
| | - Carlo Zagaglia
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, Rome, Italy
| | - Laura Vitiello
- Laboratory of Flow Cytometry, IRCCS San Raffaele Roma, Rome, Italy
| | - Meysam Sarshar
- Research Laboratories, Bambino Gesù Children’s Hospital, IRCCS, Rome, Italy
| | - Francesco Strati
- Mucosal Immunology Lab, Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
| | - Martina Pasqua
- Institute Pasteur Italy, Department of Biology and Biotechnologies "Charles Darwin", Sapienza University of Rome, Rome, Italy
| | - Fabio Grassi
- Institute for Research in Biomedicine, Faculty of Biomedical Sciences, Università della Svizzera Italiana, Bellinzona, Switzerland
| | - Mauro Nicoletti
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, Rome, Italy
| | - Anna Teresa Palamara
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, Laboratory Affiliated to Institute Pasteur Italia-Cenci Bolognetti Foundation, Rome, Italy
- Department Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Cecilia Ambrosi
- Department of Human Sciences and Quality of Life Promotion, San Raffaele University, Rome, Italy
- Laboratory of Microbiology of Chronic-Neurodegenerative Diseases, IRCCS San Raffaele Roma, Rome, Italy
| | - Daniela Scribano
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, Rome, Italy
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Tyliszczak M, Wiatrak B, Danielewski M, Szeląg A, Kucharska AZ, Sozański T. Does a pickle a day keep Alzheimer's away? Fermented food in Alzheimer's disease: A review. Exp Gerontol 2023; 184:112332. [PMID: 37967591 DOI: 10.1016/j.exger.2023.112332] [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: 09/18/2023] [Revised: 11/09/2023] [Accepted: 11/12/2023] [Indexed: 11/17/2023]
Abstract
Fermented food is commonly viewed as healthy, mostly due to its probiotic and digestion-enhancing properties and recently it has been examined with regard to the development of new therapeutic and preventive measures for Alzheimer's disease. Fermented food has been shown to have anti-inflammatory and antioxidant properties and to alter the gut microbiota. However, the exact pathogenesis of Alzheimer's disease is still unknown and its connections to systemic inflammation and gut dysbiosis, as potential targets of fermented food, require further investigation. Therefore, to sum up the current knowledge, this article reviews recent research on the pathogenesis of Alzheimer's disease with emphasis on the role of the gut-brain axis and studies examining the use of fermented foods. The analysis of the fermented food research includes clinical and preclinical in vivo and in vitro studies. The fermented food studies have shown promising effects on amyloid-β metabolism, inflammation, and cognitive impairment in animals and humans. Fermented food has great potential in developing new approaches to Alzheimer's disease treatment.
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Affiliation(s)
- Michał Tyliszczak
- Department of Pharmacology, Wroclaw Medical University, Wrocław, Poland.
| | - Benita Wiatrak
- Department of Pharmacology, Wroclaw Medical University, Wrocław, Poland
| | | | - Adam Szeląg
- Department of Pharmacology, Wroclaw Medical University, Wrocław, Poland
| | - Alicja Z Kucharska
- Department of Fruit, Vegetable, and Plant Nutraceutical Technology, Wroclaw University of Environmental and Life Sciences, Wrocław, Poland
| | - Tomasz Sozański
- Department of Preclinical Sciences, Pharmacology and Medical Diagnostics, Faculty of Medicine, Wroclaw University of Science and Technology, Wrocław, Poland
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Yadav S, Dalai P, Gowda S, Nivsarkar M, Agrawal-Rajput R. Azithromycin alters Colony Stimulating Factor-1R (CSF-1R) expression and functional output of murine bone marrow-derived macrophages: A novel report. Int Immunopharmacol 2023; 123:110688. [PMID: 37499396 DOI: 10.1016/j.intimp.2023.110688] [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: 11/19/2022] [Revised: 07/18/2023] [Accepted: 07/18/2023] [Indexed: 07/29/2023]
Abstract
Antibiotic treatment may lead to side effects that require mechanistic explanation. We investigated the effect of azithromycin (AZM) treatment on bone marrow-derived macrophage (Mφ) generation, their functional output, and the subsequent effect on bacterial clearance in a mouse model of S. flexneri infection. To our fascination, AZM increased PU.1, C/EBPβ, CSF-1R/pCSF-1R expressions leading to M2-skewed in vitro BMDM generation. Altered Mφ-functions like- phagocytosis, oxidative stress generation, inflammasome-activation, cytokine release, and phenotype (pro-inflammatory-M1, anti-inflammatory-M2) even in the presence of infection were observed with AZM treatment. AZM increased CD206, egr2, arg1 (M2-marker) expression and activity while reducing CD68, inducible nitric oxide (iNOS) expression, and activity (M1-marker) in Mφs during infection. Pro-inflammatory cytokines (TNF-α, IL-12, IL-1β) were reduced and anti-inflammatory IL-10 release was augmented by AZM-treated-iMφs (aiMφs) along with decreased asc, nlrp3, aim2, nlrp1a, caspase1 expressions, and caspase3 activity signifying that aMφs/aiMφs were primed towards an anti-inflammatory phenotype. Interestingly, CSF-1R blockade increased NO, IL-12, TNF-α, IL-1β, decreased TGF-β release, and CD206 expression in aiMφs. T-cell co-stimulatory molecule cd40, cd86, and cd80 expressions were decreased in ai/aM1-Mφs and co-cultured CD8+, CD4+ T-cells had decreased proliferation, t-bet, IFN-γ, IL-17, IL-2 but increased foxp3, TGF-β, IL-4 which were rescued with CSF-1R blockade. Thus AZM affected Mφ-functions and subsequent T-cell responses independent of its antibacterial actions. This was validated in the balb/c model of S. flexneri infection. We conclude that AZM skewed BMDM generation to anti-inflammatory M2-like via increased CSF-1R expression. This warrants further investigation of AZM-induced altered-Mφ-generation during intracellular infections.
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Affiliation(s)
- Shivani Yadav
- Department of Biological Sciences and Biotechnology, Indian Institute of Advanced Research, Gandhinagar, India
| | - Parmeswar Dalai
- Department of Biological Sciences and Biotechnology, Indian Institute of Advanced Research, Gandhinagar, India
| | - Sharath Gowda
- Department of Biological Sciences and Biotechnology, Indian Institute of Advanced Research, Gandhinagar, India
| | | | - Reena Agrawal-Rajput
- Department of Biological Sciences and Biotechnology, Indian Institute of Advanced Research, Gandhinagar, India.
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7
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Iancu MA, Profir M, Roşu OA, Ionescu RF, Cretoiu SM, Gaspar BS. Revisiting the Intestinal Microbiome and Its Role in Diarrhea and Constipation. Microorganisms 2023; 11:2177. [PMID: 37764021 PMCID: PMC10538221 DOI: 10.3390/microorganisms11092177] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 08/24/2023] [Accepted: 08/25/2023] [Indexed: 09/29/2023] Open
Abstract
The gut microbiota represents a community of microorganisms (bacteria, fungi, archaea, viruses, and protozoa) that colonize the gut and are responsible for gut mucosal structural integrity and immune and metabolic homeostasis. The relationship between the gut microbiome and human health has been intensively researched in the past years. It is now widely recognized that gut microbial composition is highly responsible for the general health of the host. Among the diseases that have been linked to an altered gut microbial population are diarrheal illnesses and functional constipation. The capacity of probiotics to modulate the gut microbiome population, strengthen the intestinal barrier, and modulate the immune system together with their antioxidant properties have encouraged the research of probiotic therapy in many gastrointestinal afflictions. Dietary and lifestyle changes and the use of probiotics seem to play an important role in easing constipation and effectively alleviating diarrhea by suppressing the germs involved. This review aims to describe how probiotic bacteria and the use of specific strains could interfere and bring benefits as an associated treatment for diarrhea and constipation.
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Affiliation(s)
- Mihaela Adela Iancu
- Department of Family Medicine, “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania;
| | - Monica Profir
- Department of Oncology, Elias University Emergency Hospital, 011461 Bucharest, Romania; (M.P.); (O.A.R.)
| | - Oana Alexandra Roşu
- Department of Oncology, Elias University Emergency Hospital, 011461 Bucharest, Romania; (M.P.); (O.A.R.)
| | - Ruxandra Florentina Ionescu
- Department of Morphological Sciences, Cell and Molecular Biology and Histology, “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania;
- Department of Cardiology I, “Dr. Carol Davila” Central Military Emergency Hospital, 010825 Bucharest, Romania
| | - Sanda Maria Cretoiu
- Department of Morphological Sciences, Cell and Molecular Biology and Histology, “Carol Davila” University of Medicine and Pharmacy, 050474 Bucharest, Romania;
| | - Bogdan Severus Gaspar
- Surgery Clinic, Emergency Clinical Hospital, 014461 Bucharest, Romania;
- Department of Surgery, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania
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Nandi I, Aroeti B. Mitogen-Activated Protein Kinases (MAPKs) and Enteric Bacterial Pathogens: A Complex Interplay. Int J Mol Sci 2023; 24:11905. [PMID: 37569283 PMCID: PMC10419152 DOI: 10.3390/ijms241511905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Revised: 07/19/2023] [Accepted: 07/19/2023] [Indexed: 08/13/2023] Open
Abstract
Diverse extracellular and intracellular cues activate mammalian mitogen-activated protein kinases (MAPKs). Canonically, the activation starts at cell surface receptors and continues via intracellular MAPK components, acting in the host cell nucleus as activators of transcriptional programs to regulate various cellular activities, including proinflammatory responses against bacterial pathogens. For instance, binding host pattern recognition receptors (PRRs) on the surface of intestinal epithelial cells to bacterial pathogen external components trigger the MAPK/NF-κB signaling cascade, eliciting cytokine production. This results in an innate immune response that can eliminate the bacterial pathogen. However, enteric bacterial pathogens evolved sophisticated mechanisms that interfere with such a response by delivering virulent proteins, termed effectors, and toxins into the host cells. These proteins act in numerous ways to inactivate or activate critical components of the MAPK signaling cascades and innate immunity. The consequence of such activities could lead to successful bacterial colonization, dissemination, and pathogenicity. This article will review enteric bacterial pathogens' strategies to modulate MAPKs and host responses. It will also discuss findings attempting to develop anti-microbial treatments by targeting MAPKs.
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Affiliation(s)
| | - Benjamin Aroeti
- Department of Biological Chemistry, Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem 9190410, Israel;
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Wang KC, Lerche MH, Ardenkjær-Larsen JH, Jensen PR. Formate Metabolism in Shigella flexneri and Its Effect on HeLa Cells at Different Stages during the Infectious Process. Microbiol Spectr 2023; 11:e0063122. [PMID: 37042762 PMCID: PMC10269805 DOI: 10.1128/spectrum.00631-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 03/16/2023] [Indexed: 04/13/2023] Open
Abstract
Shigellosis caused by Shigella is one of the most important foodborne illnesses in global health, but little is known about the metabolic cross talk between this bacterial pathogen and its host cells during the different stages of the infection process. A detailed understanding of the metabolism can potentially lead to new drug targets remedying the pressing problem of antibiotic resistance. Here, we use stable isotope-resolved metabolomics as an unbiased and fast method to investigate how Shigella metabolizes 13C-glucose in three different environments: inside the host cells, adhering to the host cells, and alone in suspension. We find that especially formate metabolism by bacteria is sensitive to these different environments. The role of formate in pathogen metabolism is sparsely described in the literature compared to the roles of acetate and butyrate. However, its metabolic pathway is regarded as a potential drug target due to its production in microorganisms and its absence in humans. Our study provides new knowledge about the regulatory effect of formate. Bacterial metabolism of formate is pH dependent when studied alone in culture medium, whereas this effect is less pronounced when the bacteria adhere to the host cells. Once the bacteria are inside the host cells, we find that formate accumulation is reduced. Formate also affects the host cells resulting in a reduced infection rate. This was correlated to an increased immune response. Thus, intriguingly formate plays a double role in pathogenesis by increasing the virulence of Shigella and at the same time stimulating the immune response of the host. IMPORTANCE Bacterial infection is a pressing societal concern due to development of resistance toward known antibiotics. Central carbon metabolism has been suggested as a potential new target for drug development, but metabolic changes upon infection remain incompletely understood. Here, we used a cellular infection model to study how the bacterial pathogen Shigella adapts its metabolism depending on the environment starting from the extracellular medium until Shigella successfully invaded and proliferated inside host cells. The mixed-acid fermentation of Shigella was the major metabolic pathway during the infectious process, and the glucose-derived metabolite formate surprisingly played a divergent role in the pathogen and in the host cell. Our data show reduced infection rate when both host cells and bacteria were treated with formate, which correlated with an upregulated immune response in the host cells. The formate metabolism in Shigella thus potentially provides a route toward alternative treatment strategies for Shigella prevention.
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Affiliation(s)
- Ke-Chuan Wang
- Center for Hyperpolarization in Magnetic Resonance, Department of Health Technology, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Mathilde Hauge Lerche
- Center for Hyperpolarization in Magnetic Resonance, Department of Health Technology, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Jan Henrik Ardenkjær-Larsen
- Center for Hyperpolarization in Magnetic Resonance, Department of Health Technology, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Pernille Rose Jensen
- Center for Hyperpolarization in Magnetic Resonance, Department of Health Technology, Technical University of Denmark, Kongens Lyngby, Denmark
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Trirocco R, Pasqua M, Tramonti A, Grossi M, Colonna B, Paiardini A, Prosseda G. Fatty Acids Abolish Shigella Virulence by Inhibiting Its Master Regulator, VirF. Microbiol Spectr 2023; 11:e0077823. [PMID: 37140433 PMCID: PMC10269687 DOI: 10.1128/spectrum.00778-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 04/10/2023] [Indexed: 05/05/2023] Open
Abstract
The pathogenicity of Shigella, the intracellular pathogen responsible for human bacillary dysentery, depends on a coordinated and tightly regulated expression of its virulence determinants. This is the result of a cascade organization of its positive regulators, with VirF, a transcriptional activator belonging to the AraC-XylS family, in a pivotal position. VirF itself is submitted to several well-known regulations at the transcriptional level. In this work, we present evidence for a novel posttranslational regulatory mechanism of VirF mediated by the inhibitory interaction with specific fatty acids. By homology modeling and molecular docking analyses, we identify a jelly roll motif in the structure of ViF capable of interacting with medium-chain saturated and long-chain unsaturated fatty acids. In vitro and in vivo assays show that capric, lauric, myristoleic, palmitoleic, and sapienic acids interact effectively with the VirF protein, abolishing its transcription-promoting activity. This silences the virulence system of Shigella, leading to a drastic reduction in its ability to invade epithelial cells and proliferate in their cytoplasm. IMPORTANCE In the absence of a valid vaccine, the main therapeutic approach currently used to treat shigellosis is based on the use of antibiotics. The emergence of antibiotic resistance jeopardizes the future effectiveness of this approach. The importance of the present work resides both in the identification of a new level of posttranslational regulation of the Shigella virulence system and in the characterization of a mechanism offering new opportunities for the design of antivirulence compounds, which may change the treatment paradigm of Shigella infections by limiting the emergence of antibiotic-resistant bacteria.
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Affiliation(s)
- Rita Trirocco
- Institute Pasteur Italia, Department of Biology and Biotechnologies “Charles Darwin”, Sapienza University of Rome, Rome, Italy
| | - Martina Pasqua
- Institute Pasteur Italia, Department of Biology and Biotechnologies “Charles Darwin”, Sapienza University of Rome, Rome, Italy
| | - Angela Tramonti
- Institute of Molecular Biology and Pathology, National Research Council, Rome, Italy
| | - Milena Grossi
- Institute Pasteur Italia, Department of Biology and Biotechnologies “Charles Darwin”, Sapienza University of Rome, Rome, Italy
| | - Bianca Colonna
- Institute Pasteur Italia, Department of Biology and Biotechnologies “Charles Darwin”, Sapienza University of Rome, Rome, Italy
| | | | - Gianni Prosseda
- Institute Pasteur Italia, Department of Biology and Biotechnologies “Charles Darwin”, Sapienza University of Rome, Rome, Italy
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11
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Blacksell SD, Dhawan S, Kusumoto M, Le KK, Davis BJ, Summermatter K, O'Keefe J, Kozlovac J, Almuhairi SS, Sendow I, Scheel CM, Ahumibe A, Masuku ZM, Bennett AM, Kojima K, Harper DR, Hamilton K. The Biosafety Research Road Map: The Search for Evidence to Support Practices in the Laboratory- Shigella spp. APPLIED BIOSAFETY 2023; 28:96-101. [PMID: 37342516 PMCID: PMC10278014 DOI: 10.1089/apb.2022.0046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/23/2023]
Abstract
Introduction Shigella bacteria cause shigellosis, a gastrointestinal infection most often acquired from contaminated food or water. Methods In this review, the general characteristics of Shigella bacteria are described, cases of laboratory-acquired infections (LAIs) are discussed, and evidence gaps in current biosafety practices are identified. Results LAIs are undoubtedly under-reported. Owing to the low infectious dose, rigorous biosafety level 2 practices are required to prevent LAIs resulting from sample manipulation or contact with infected surfaces. Conclusions It is recommended that, before laboratory work with Shigella, an evidence-based risk assessment be conducted. Particular emphasis should be placed on personal protective equipment, handwashing, and containment practices for procedures that generate aerosols or droplets.
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Affiliation(s)
- Stuart D. Blacksell
- Mahidol-Oxford Tropical Research Medicine Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Nuffield Department of Medicine Research Building, University of Oxford, Oxford, United Kingdom
| | - Sandhya Dhawan
- Mahidol-Oxford Tropical Research Medicine Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Marina Kusumoto
- Mahidol-Oxford Tropical Research Medicine Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Kim Khanh Le
- Mahidol-Oxford Tropical Research Medicine Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Ben J. Davis
- Mahidol-Oxford Tropical Research Medicine Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | | | - Joseph O'Keefe
- Ministry for Primary Industries, Wellington, New Zealand
| | - Joseph Kozlovac
- U.S. Department of Agriculture, Agricultural Research Service, Beltsville, Maryland, USA
| | | | - Indrawati Sendow
- Research Center for Veterinary Science, National Research and Innovation Agency, Indonesia
| | - Christina M. Scheel
- WHO Collaborating Center for Biosafety and Biosecurity, Office of the Associate Director for Laboratory Science, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Anthony Ahumibe
- Nigeria Centre for Disease Control and Prevention, Abuja, Nigeria
| | - Zibusiso M. Masuku
- National Institute for Communicable Diseases of the National Health Laboratory Services, Sandringham, South Africa
| | | | - Kazunobu Kojima
- Department of Epidemic and Pandemic Preparedness and Prevention, World Health Organization, Geneva, Switzerland
| | - David R. Harper
- The Royal Institute of International Affairs, London, United Kingdom
| | - Keith Hamilton
- World Organisation for Animal Health (OIE), Paris, France
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12
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Toward a Shigella Vaccine: Opportunities and Challenges to Fight an Antimicrobial-Resistant Pathogen. Int J Mol Sci 2023; 24:ijms24054649. [PMID: 36902092 PMCID: PMC10003550 DOI: 10.3390/ijms24054649] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/23/2023] [Accepted: 02/24/2023] [Indexed: 03/04/2023] Open
Abstract
Shigellosis causes more than 200,000 deaths worldwide and most of this burden falls on Low- and Middle-Income Countries (LMICs), with a particular incidence in children under 5 years of age. In the last decades, Shigella has become even more worrisome because of the onset of antimicrobial-resistant strains (AMR). Indeed, the WHO has listed Shigella as one of the priority pathogens for the development of new interventions. To date, there are no broadly available vaccines against shigellosis, but several candidates are being evaluated in preclinical and clinical studies, bringing to light very important data and information. With the aim to facilitate the understanding of the state-of-the-art of Shigella vaccine development, here we report what is known about Shigella epidemiology and pathogenesis with a focus on virulence factors and potential antigens for vaccine development. We discuss immunity after natural infection and immunization. In addition, we highlight the main characteristics of the different technologies that have been applied for the development of a vaccine with broad protection against Shigella.
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13
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Pakbin B, Brück WM, Brück TB. Molecular Mechanisms of Shigella Pathogenesis; Recent Advances. Int J Mol Sci 2023; 24:ijms24032448. [PMID: 36768771 PMCID: PMC9917014 DOI: 10.3390/ijms24032448] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/21/2023] [Accepted: 01/23/2023] [Indexed: 01/28/2023] Open
Abstract
Shigella species are the main cause of bacillary diarrhoea or shigellosis in humans. These organisms are the inhabitants of the human intestinal tract; however, they are one of the main concerns in public health in both developed and developing countries. In this study, we reviewed and summarised the previous studies and recent advances in molecular mechanisms of pathogenesis of Shigella Dysenteriae and non-Dysenteriae species. Regarding the molecular mechanisms of pathogenesis and the presence of virulence factor encoding genes in Shigella strains, species of this bacteria are categorised into Dysenteriae and non-Dysenteriae clinical groups. Shigella species uses attachment, invasion, intracellular motility, toxin secretion and host cell interruption mechanisms, causing mild diarrhoea, haemorrhagic colitis and haemolytic uremic syndrome diseases in humans through the expression of effector delivery systems, protein effectors, toxins, host cell immune system evasion and iron uptake genes. The investigation of these genes and molecular mechanisms can help us to develop and design new methods to detect and differentiate these organisms in food and clinical samples and determine appropriate strategies to prevent and treat the intestinal and extraintestinal infections caused by these enteric pathogens.
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Affiliation(s)
- Babak Pakbin
- Werner Siemens Chair of Synthetic Biotechnology, Department of Chemistry, Technical University of Munich (TUM), Lichtenberg Str. 4, 85748 Garching bei München, Germany
- Institute for Life Technologies, University of Applied Sciences Western Switzerland Valais-Wallis, 1950 Sion, Switzerland
| | - Wolfram Manuel Brück
- Institute for Life Technologies, University of Applied Sciences Western Switzerland Valais-Wallis, 1950 Sion, Switzerland
- Correspondence: (W.M.B.); (T.B.B.)
| | - Thomas B. Brück
- Werner Siemens Chair of Synthetic Biotechnology, Department of Chemistry, Technical University of Munich (TUM), Lichtenberg Str. 4, 85748 Garching bei München, Germany
- Correspondence: (W.M.B.); (T.B.B.)
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14
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Roles of Two-Component Signal Transduction Systems in Shigella Virulence. Biomolecules 2022; 12:biom12091321. [PMID: 36139160 PMCID: PMC9496106 DOI: 10.3390/biom12091321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 09/12/2022] [Accepted: 09/13/2022] [Indexed: 11/17/2022] Open
Abstract
Two-component signal transduction systems (TCSs) are widespread types of protein machinery, typically consisting of a histidine kinase membrane sensor and a cytoplasmic transcriptional regulator that can sense and respond to environmental signals. TCSs are responsible for modulating genes involved in a multitude of bacterial functions, including cell division, motility, differentiation, biofilm formation, antibiotic resistance, and virulence. Pathogenic bacteria exploit the capabilities of TCSs to reprogram gene expression according to the different niches they encounter during host infection. This review focuses on the role of TCSs in regulating the virulence phenotype of Shigella, an intracellular pathogen responsible for severe human enteric syndrome. The pathogenicity of Shigella is the result of the complex action of a wide number of virulence determinants located on the chromosome and on a large virulence plasmid. In particular, we will discuss how five TCSs, EnvZ/OmpR, CpxA/CpxR, ArcB/ArcA, PhoQ/PhoP, and EvgS/EvgA, contribute to linking environmental stimuli to the expression of genes related to virulence and fitness within the host. Considering the relevance of TCSs in the expression of virulence in pathogenic bacteria, the identification of drugs that inhibit TCS function may represent a promising approach to combat bacterial infections.
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15
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Invading Bacterial Pathogens Activate Transcription Factor EB in Epithelial Cells through the Amino Acid Starvation Pathway of mTORC1 Inhibition. Mol Cell Biol 2022; 42:e0024122. [PMID: 36005752 PMCID: PMC9476939 DOI: 10.1128/mcb.00241-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Upon pathogen infection, intricate innate signaling cascades are induced to initiate the transcription of immune effectors, including cytokines and chemokines. Transcription factor EB (TFEB), a master regulator of lysosomal biogenesis and autophagy genes, was found recently to be a novel regulator of innate immunity in both Caenorhabditis elegans and mammals. Despite TFEB participating in critical mechanisms of pathogen recognition and in the transcriptional response to infection in mammalian macrophages, little is known about its roles in the infected epithelium or infected nonimmune cells in general. Here, we demonstrate that TFEB is activated in nonimmune cells upon infection with bacterial pathogens through a pathway dependent on mTORC1 inhibition and RAG-GTPase activity, reflecting the importance of membrane damage and amino acid starvation responses during infection. Additionally, we present data demonstrating that although TFEB does not affect bacterial killing or load in nonimmune cells, it alters the host transcriptome upon infection, thus promoting an antibacterial transcriptomic landscape. Elucidating the roles of TFEB in infected nonimmune cells and the upstream signaling cascade provides critical insight into understanding how cells recognize and respond to bacterial pathogens.
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16
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Abstract
The first critical step in a virus’s infection cycle is attachment to its host. This interaction is precise enough to ensure the virus will be able to productively infect the cell, but some flexibility can be beneficial to enable coevolution and host range switching or expansion. Bacteriophage Sf6 utilizes a two-step process to recognize and attach to its host Shigella flexneri. Sf6 first recognizes the lipopolysaccharide (LPS) of S. flexneri and then binds outer membrane protein (Omp) A or OmpC. This phage infects serotype Y strains but can also form small, turbid plaques on serotype 2a2; turbid plaques appear translucent rather than transparent, indicating greater survival of bacteria. Reduced plating efficiency further suggested inefficient infection. To examine the interactions between Sf6 and this alternate host, phages were experimentally evolved using mixed populations of S. flexneri serotypes Y and 2a2. The recovered mutants could infect serotype 2a2 with greater efficiency than the ancestral Sf6, forming clear plaques on both serotypes. All mutations mapped to two distinct regions of the receptor-binding tailspike protein: (i) adjacent to the LPS binding site near the N terminus; and (ii) at the distal, C-terminal tip of the protein. Although we anticipated interactions between the Sf6 tailspike and 2a2 O-antigen to be weak, LPS of this serotype appears to inhibit infection through strong binding of particles, effectively removing them from the environment. The mutations of the evolved strains reduce the inhibitory effect by either reducing electrostatic interactions with the O-antigen or increasing reliance on the Omp secondary receptors. IMPORTANCE Viruses depend on host cells to propagate themselves. In mixed populations and communities of host cells, finding these susceptible host cells may have to be balanced with avoiding nonhost cells. Alternatively, being able to infect new cell types can increase the fitness of the virus. Many bacterial viruses use a two-step process to identify their hosts, binding first to an LPS receptor and then to a host protein. For Shigella virus Sf6, the tailspike protein was previously known to bind the LPS receptor. Genetic data from this work imply the tailspike also binds to the protein receptor. By experimentally evolving Sf6, we also show that point mutations in this protein can dramatically affect the binding of one or both receptors. This may provide Sf6 flexibility in identifying host cells and the ability to rapidly alter its host range under selective pressure.
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17
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Basak P, Maitra P, Khan U, Saha K, Bhattacharya SS, Dutta M, Bhattacharya S. Capsaicin Inhibits Shigella flexneri Intracellular Growth by Inducing Autophagy. Front Pharmacol 2022; 13:903438. [PMID: 35873583 PMCID: PMC9298657 DOI: 10.3389/fphar.2022.903438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 05/16/2022] [Indexed: 11/13/2022] Open
Abstract
Antibiotic treatment plays an essential role in preventing Shigella infection. However, incidences of global rise in antibiotic resistance create a major challenge to treat bacterial infection. In this context, there is an urgent need for newer approaches to reduce S. flexneri burden. This study largely focuses on the role of the herbal compound capsaicin (Caps) in inhibiting S. flexneri growth and evaluating the molecular mechanism behind bacterial clearance. Here, we show for the first time that Caps inhibits intracellular S. flexneri growth by inducing autophagy. Activation of autophagy by Caps is mediated through transcription factor TFEB, a master regulator of autophagosome biogenesis. Caps induced the nuclear localization of TFEB. Activation of TFEB further induces the gene transcription of autophagosomal genes. Our findings revealed that the inhibition of autophagy by silencing TFEB and Atg5 induces bacterial growth. Hence, Caps-induced autophagy is one of the key factors responsible for bacterial clearance. Moreover, Caps restricted the intracellular proliferation of S. flexneri-resistant strain. The efficacy of Caps in reducing S. flexneri growth was confirmed by an animal model. This study showed for the first time that S. flexneri infection can be inhibited by inducing autophagy. Overall observations suggest that Caps activates TFEB to induce autophagy and thereby combat S. flexneri infection.
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Affiliation(s)
- Priyanka Basak
- Division of Biochemistry, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Priyanka Maitra
- Division of Biochemistry, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Uzma Khan
- Division of Biochemistry, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Kalyani Saha
- Division of Biochemistry, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | | | - Moumita Dutta
- Division of Electron Microscopy, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Sushmita Bhattacharya
- Division of Biochemistry, National Institute of Cholera and Enteric Diseases, Kolkata, India
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18
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The AraC/XylS Protein MxiE and Its Coregulator IpgC Control a Negative Feedback Loop in the Transcriptional Cascade That Regulates Type III Secretion in Shigella flexneri. J Bacteriol 2022; 204:e0013722. [PMID: 35703565 DOI: 10.1128/jb.00137-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Members of the AraC family of transcriptional regulators (AFTRs) control the expression of many genes important to cellular processes, including virulence. In Shigella species, the type III secretion system (T3SS), a key determinant for host cell invasion, is regulated by the three-tiered VirF/VirB/MxiE transcriptional cascade. Both VirF and MxiE belong to the AFTRs and are characterized as positive transcriptional regulators. Here, we identify a novel regulatory activity for MxiE and its coregulator IpgC, which manifests as a negative feedback loop in the VirF/VirB/MxiE transcriptional cascade. Our findings show that MxiE and IpgC downregulate the virB promoter and, hence, VirB protein production, thus decreasing VirB-dependent promoter activity at ospD1, one of the nearly 50 VirB-dependent genes. At the virB promoter, regions required for negative MxiE- and IpgC-dependent regulation were mapped and found to be coincident with regions required for positive VirF-dependent regulation. In tandem, negative MxiE- and IpgC-dependent regulation of the virB promoter only occurred in the presence of VirF, suggesting that MxiE and IpgC can function to counter VirF activation of the virB promoter. Lastly, MxiE and IpgC do not downregulate another VirF-activated promoter, icsA, demonstrating that this negative feedback loop targets the virB promoter. Our study provides insight into a mechanism that may reprogram Shigella virulence gene expression following type III secretion and provides the impetus to examine if MxiE and IpgC homologs in other important bacterial pathogens, such as Burkholderia pseudomallei and Salmonella enterica serovars Typhimurium and Typhi, coordinate similar negative feedback loops. IMPORTANCE The large AraC family of transcriptional regulators (AFTRs) control virulence gene expression in many bacterial pathogens. In Shigella species, the AraC/XylS protein MxiE and its coregulator IpgC positively regulate the expression of type III secretion system genes within the three-tiered VirF/VirB/MxiE transcriptional cascade. Our findings suggest a negative feedback loop in the VirF/VirB/MxiE cascade, in which MxiE and IpgC counter VirF-dependent activation of the virB promoter, thus making this the first characterization of negative MxiE- and IpgC-dependent regulation. Our study provides insight into a mechanism that likely reprograms Shigella virulence gene expression following type III secretion, which has implications for other important bacterial pathogens with functional homologs of MxiE and IpgC.
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19
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Boutet E, Djerroud S, Perreault J. Small RNAs beyond Model Organisms: Have We Only Scratched the Surface? Int J Mol Sci 2022; 23:ijms23084448. [PMID: 35457265 PMCID: PMC9029176 DOI: 10.3390/ijms23084448] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 04/14/2022] [Accepted: 04/15/2022] [Indexed: 01/27/2023] Open
Abstract
Small RNAs (sRNAs) are essential regulators in the adaptation of bacteria to environmental changes and act by binding targeted mRNAs through base complementarity. Approximately 550 distinct families of sRNAs have been identified since their initial characterization in the 1980s, accelerated by the emergence of RNA-sequencing. Small RNAs are found in a wide range of bacterial phyla, but they are more prominent in highly researched model organisms compared to the rest of the sequenced bacteria. Indeed, Escherichia coli and Salmonella enterica contain the highest number of sRNAs, with 98 and 118, respectively, with Enterobacteriaceae encoding 145 distinct sRNAs, while other bacteria families have only seven sRNAs on average. Although the past years brought major advances in research on sRNAs, we have perhaps only scratched the surface, even more so considering RNA annotations trail behind gene annotations. A distinctive trend can be observed for genes, whereby their number increases with genome size, but this is not observable for RNAs, although they would be expected to follow the same trend. In this perspective, we aimed at establishing a more accurate representation of the occurrence of sRNAs in bacteria, emphasizing the potential for novel sRNA discoveries.
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20
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Péter B, Farkas E, Kurunczi S, Szittner Z, Bősze S, Ramsden JJ, Szekacs I, Horvath R. Review of Label-Free Monitoring of Bacteria: From Challenging Practical Applications to Basic Research Perspectives. BIOSENSORS 2022; 12:bios12040188. [PMID: 35448248 PMCID: PMC9026780 DOI: 10.3390/bios12040188] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 03/07/2022] [Accepted: 03/11/2022] [Indexed: 05/10/2023]
Abstract
Novel biosensors already provide a fast way to detect the adhesion of whole bacteria (or parts of them), biofilm formation, and the effect of antibiotics. Moreover, the detection sensitivities of recent sensor technologies are large enough to investigate molecular-scale biological processes. Usually, these measurements can be performed in real time without using labeling. Despite these excellent capabilities summarized in the present work, the application of novel, label-free sensor technologies in basic biological research is still rare; the literature is dominated by heuristic work, mostly monitoring the presence and amount of a given analyte. The aims of this review are (i) to give an overview of the present status of label-free biosensors in bacteria monitoring, and (ii) to summarize potential novel directions with biological relevancies to initiate future development. Optical, mechanical, and electrical sensing technologies are all discussed with their detailed capabilities in bacteria monitoring. In order to review potential future applications of the outlined techniques in bacteria research, we summarize the most important kinetic processes relevant to the adhesion and survival of bacterial cells. These processes are potential targets of kinetic investigations employing modern label-free technologies in order to reveal new fundamental aspects. Resistance to antibacterials and to other antimicrobial agents, the most important biological mechanisms in bacterial adhesion and strategies to control adhesion, as well as bacteria-mammalian host cell interactions are all discussed with key relevancies to the future development and applications of biosensors.
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Affiliation(s)
- Beatrix Péter
- Nanobiosensorics Laboratory, Centre for Energy Research, Institute of Technical Physics and Materials Science, 1121 Budapest, Hungary; (E.F.); (S.K.); (Z.S.); (I.S.)
- Correspondence: (B.P.); (R.H.)
| | - Eniko Farkas
- Nanobiosensorics Laboratory, Centre for Energy Research, Institute of Technical Physics and Materials Science, 1121 Budapest, Hungary; (E.F.); (S.K.); (Z.S.); (I.S.)
| | - Sandor Kurunczi
- Nanobiosensorics Laboratory, Centre for Energy Research, Institute of Technical Physics and Materials Science, 1121 Budapest, Hungary; (E.F.); (S.K.); (Z.S.); (I.S.)
| | - Zoltán Szittner
- Nanobiosensorics Laboratory, Centre for Energy Research, Institute of Technical Physics and Materials Science, 1121 Budapest, Hungary; (E.F.); (S.K.); (Z.S.); (I.S.)
| | - Szilvia Bősze
- MTA-ELTE Research Group of Peptide Chemistry, Eötvös Loránd Research Network (ELKH), Institute of Chemistry, Eötvös Loránd University, 1120 Budapest, Hungary;
- National Public Health Center, 1097 Budapest, Hungary
| | - Jeremy J. Ramsden
- Clore Laboratory, Department of Biomedical Research, University of Buckingham, Buckingham MK18 1AD, UK;
| | - Inna Szekacs
- Nanobiosensorics Laboratory, Centre for Energy Research, Institute of Technical Physics and Materials Science, 1121 Budapest, Hungary; (E.F.); (S.K.); (Z.S.); (I.S.)
| | - Robert Horvath
- Nanobiosensorics Laboratory, Centre for Energy Research, Institute of Technical Physics and Materials Science, 1121 Budapest, Hungary; (E.F.); (S.K.); (Z.S.); (I.S.)
- Correspondence: (B.P.); (R.H.)
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21
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Anam K, Endharti AT, Poeranto S, Sujuti H, Hidayati DYN, Prawiro SR. Shigella flexneri vaccine development: Oral administration of peptides derived from the 49.8 kDa pili protein subunit activates the intestinal immune response in mice. Vet World 2022; 15:281-287. [PMID: 35400957 PMCID: PMC8980390 DOI: 10.14202/vetworld.2022.281-287] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 01/05/2022] [Indexed: 11/16/2022] Open
Abstract
Background and Aim: The morbidity and mortality of Shigella infections remain a global challenge. Epitope-based vaccine development is an emerging strategy to prevent bacterial invasion. This study aimed to identify the ability of the 49.8 kDa pili subunit adhesin protein epitope of Shigella flexneri to induce an intestinal immune response in mice. Materials and Methods: Thirty adult male Balb/c mice were divided into a control group, cholera toxin B subunit (CTB) group, CTB+QSSTGTNSQSDLDS (pep_1) group, CTB+DTTITKAETKTVTKNQVVDTPVTTDAAK (pep_2) group, and CTB+ ATLGATLNRLDFNVNNK (pep_3). We performed immunization by orally administering 50 μg of antigen and 50 μl of adjuvant once a week over 4 weeks. We assessed the cellular immune response by quantifying T helper 2 (Th2) and Th17 using flow cytometry. In addition, we assessed the humoral immune response by quantifying interleukin (IL-4), IL-17, secretory immunoglobulin A (sIgA), and β-defensin using enzyme-linked immunoassay. Statistical analysis was performed using one-way analysis of variance and Kruskal–Wallis test. Results: Peptide oral immunization increases the cellular immune response as reflected by the increase of Th2 (p=0.019) and Th17 (p=0.004) cell counts, particularly in the CTB_pep_1 group. Humoral immune response activation was demonstrated by increased IL-4 levels, especially in the CTB+pep_3 group (p=0.000). The IL-17 level was increased significantly in the CTB+pep_1 group (p=0.042). The mucosal immune response was demonstrated by the sIgA levels increase in the CTB+pep_3 group (p=0.042) and the β-defensin protein levels (p=0.000). Conclusion: All selected peptides activated the cellular and humoral immune responses in the intestine of mice. Further studies are necessary to optimize antigen delivery and evaluate whether the neutralizing properties of these peptides allow them to prevent bacterial infection.
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Affiliation(s)
- Khoirul Anam
- Doctoral Program in Medical Science, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia; Study Program of Medical Laboratory Technology, Institute of Health and Science Technology Wiyata Husada, Samarinda, Indonesia
| | - Agustina Tri Endharti
- Department of Parasitology, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
| | - Sri Poeranto
- Department of Parasitology, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
| | - Hidayat Sujuti
- Department of Biochemistry, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
| | - Dwi Yuni Nur Hidayati
- Department of Clinical Microbiology, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
| | - Sumarno Reto Prawiro
- Department of Clinical Microbiology, Faculty of Medicine, Universitas Brawijaya, Malang, Indonesia
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22
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Jalal K, Abu-Izneid T, Khan K, Abbas M, Hayat A, Bawazeer S, Uddin R. Identification of vaccine and drug targets in Shigella dysenteriae sd197 using reverse vaccinology approach. Sci Rep 2022; 12:251. [PMID: 34997046 PMCID: PMC8742002 DOI: 10.1038/s41598-021-03988-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Accepted: 12/07/2021] [Indexed: 11/09/2022] Open
Abstract
Shigellosis is characterized as diarrheal disease that causes a high mortality rate especially in children, elderly and immunocompromised patients. More recently, the World Health Organization advised safe vaccine designing against shigellosis due to the emergence of Shigella dysenteriae resistant strains. Therefore, the aim of this study is to identify novel drug targets as well as the design of the potential vaccine candidates and chimeric vaccine models against Shigella dysenteriae. A computational based Reverse Vaccinology along with subtractive genomics analysis is one of the robust approaches used for the prioritization of drug targets and vaccine candidates through direct screening of genome sequence assemblies. Herein, a successfully designed peptide-based novel highly antigenic chimeric vaccine candidate against Shigella dysenteriae sd197 strain is proposed. The study resulted in six epitopes from outer membrane WP_000188255.1 (Fe (3+) dicitrate transport protein FecA) that ultimately leads to the construction of twelve vaccine models. Moreover, V9 construct was found to be highly immunogenic, non-toxic, non-allergenic, highly antigenic, and most stable in terms of molecular docking and simulation studies against six HLAs and TLRS/MD complex. So far, this protein and multiepitope have never been characterized as vaccine targets against Shigella dysenteriae. The current study proposed that V9 could be a significant vaccine candidate against shigellosis and to ascertain that further experiments may be applied by the scientific community focused on shigellosis.
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Affiliation(s)
- Khurshid Jalal
- H.E.J. Research Institute of Chemistry International Center for Chemical and Biological Sciences, University of Karachi, Karachi, Pakistan
| | - Tareq Abu-Izneid
- Pharmaceutical Sciences, College of Pharmacy, Al Ain University Al Ain Campus, Al Ain, United Arab Emirates
| | - Kanwal Khan
- Lab 103 PCMD Ext. Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, 75270, Pakistan
| | - Muhammad Abbas
- Department of Pharmacy, Abdul Wali Khan University Mardan KP, Mardan, Pakistan
| | - Ajmal Hayat
- Department of Pharmacy, Abdul Wali Khan University Mardan KP, Mardan, Pakistan
| | - Sami Bawazeer
- Pharmacognosy Department, College of Pharmacy, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Reaz Uddin
- Lab 103 PCMD Ext. Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, 75270, Pakistan.
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23
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High-Throughput CRISPR Screens To Dissect Macrophage- Shigella Interactions. mBio 2021; 12:e0215821. [PMID: 34933448 PMCID: PMC8689513 DOI: 10.1128/mbio.02158-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Shigellosis causes most diarrheal deaths worldwide, particularly affecting children. Shigella invades and replicates in the epithelium of the large intestine, eliciting inflammation and tissue destruction. To understand how Shigella rewires macrophages prior to epithelium invasion, we performed genome-wide and focused secondary CRISPR knockout and CRISPR interference (CRISPRi) screens in Shigella flexneri-infected human monocytic THP-1 cells. Knockdown of the Toll-like receptor 1/2 signaling pathway significantly reduced proinflammatory cytokine and chemokine production, enhanced host cell survival, and controlled intracellular pathogen growth. Knockdown of the enzymatic component of the mitochondrial pyruvate dehydrogenase complex enhanced THP-1 cell survival. Small-molecule inhibitors blocking key components of these pathways had similar effects; these were validated with human monocyte-derived macrophages, which closely mimic the in vivo physiological state of macrophages postinfection. High-throughput CRISPR screens can elucidate how S. flexneri triggers inflammation and redirects host pyruvate catabolism for energy acquisition before killing macrophages, pointing to new shigellosis therapies.
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Rahmatelahi H, El-Matbouli M, Menanteau-Ledouble S. Delivering the pain: an overview of the type III secretion system with special consideration for aquatic pathogens. Vet Res 2021; 52:146. [PMID: 34924019 PMCID: PMC8684695 DOI: 10.1186/s13567-021-01015-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 11/08/2021] [Indexed: 11/10/2022] Open
Abstract
Gram-negative bacteria are known to subvert eukaryotic cell physiological mechanisms using a wide array of virulence factors, among which the type three-secretion system (T3SS) is often one of the most important. The T3SS constitutes a needle-like apparatus that the bacterium uses to inject a diverse set of effector proteins directly into the cytoplasm of the host cells where they can hamper the host cellular machinery for a variety of purposes. While the structure of the T3SS is somewhat conserved and well described, effector proteins are much more diverse and specific for each pathogen. The T3SS can remodel the cytoskeleton integrity to promote intracellular invasion, as well as silence specific eukaryotic cell signals, notably to hinder or elude the immune response and cause apoptosis. This is also the case in aquatic bacterial pathogens where the T3SS can often play a central role in the establishment of disease, although it remains understudied in several species of important fish pathogens, notably in Yersinia ruckeri. In the present review, we summarise what is known of the T3SS, with a special focus on aquatic pathogens and suggest some possible avenues for research including the potential to target the T3SS for the development of new anti-virulence drugs.
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Affiliation(s)
- Hadis Rahmatelahi
- Clinical Division of Fish Medicine, University of Veterinary Medicine, 1210, Vienna, Austria
| | - Mansour El-Matbouli
- Clinical Division of Fish Medicine, University of Veterinary Medicine, 1210, Vienna, Austria
| | - Simon Menanteau-Ledouble
- Clinical Division of Fish Medicine, University of Veterinary Medicine, 1210, Vienna, Austria.
- Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajers Vej 7H, 9220, Aalborg Ø, Denmark.
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Abstract
Shigella flexneri is an intracellular human pathogen that invades colonic cells and causes bloody diarrhea. S. flexneri evolved from commensal Escherichia coli, and genome comparisons reveal that S. flexneri has lost approximately 20% of its genes through the process of pathoadaptation, including a disproportionate number of genes associated with the turnover of the nucleotide-based second messenger cyclic di-GMP (c-di-GMP); however, the remaining c-di-GMP turnover enzymes are highly conserved. c-di-GMP regulates many behavioral changes in other bacteria in response to changing environmental conditions, including biofilm formation, but this signaling system has not been examined in S. flexneri. In this study, we expressed VCA0956, a constitutively active c-di-GMP synthesizing diguanylate cyclase (DGC) from Vibrio cholerae, in S. flexneri to determine if virulence phenotypes were regulated by c-di-GMP. We found that expressing VCA0956 in S. flexneri increased c-di-GMP levels, and this corresponds with increased biofilm formation and reduced acid resistance, host cell invasion, and plaque size. We examined the impact of VCA0956 expression on the S. flexneri transcriptome and found that genes related to acid resistance were repressed, and this corresponded with decreased survival to acid shock. We also found that individual S. flexneri DGC mutants exhibit reduced biofilm formation and reduced host cell invasion and plaque size, as well as increased resistance to acid shock. This study highlights the importance of c-di-GMP signaling in regulating S. flexneri virulence phenotypes. IMPORTANCE The intracellular human pathogen Shigella causes dysentery, resulting in as many as one million deaths per year. Currently, there is no approved vaccine for the prevention of shigellosis, and the incidence of antimicrobial resistance among Shigella species is on the rise. Here, we explored how the widely conserved c-di-GMP bacterial signaling system alters Shigella behaviors associated with pathogenesis. We found that expressing or removing enzymes associated with c-di-GMP synthesis results in changes in Shigella's ability to form biofilms, invade host cells, form lesions in host cell monolayers, and resist acid stress.
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Śliwka P, Ochocka M, Skaradzińska A. Applications of bacteriophages against intracellular bacteria. Crit Rev Microbiol 2021; 48:222-239. [PMID: 34428105 DOI: 10.1080/1040841x.2021.1960481] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Infectious diseases pose a significant threat to both human and animal populations. Intracellular bacteria are a group of pathogens that invade and survive within the interior of eukaryotic cells, which in turn protect them from antibacterial drugs and the host immune system. Limited penetration of antibacterials into host cells results in insufficient bacterial clearance and treatment failure. Bacteriophages have, over the decades, been proved to play an important role in combating bacterial infections (phage therapy), making them an important alternative to classical antibiotic strategies today. Phages have been found to be effective at killing various species of extracellular bacteria, but little is still known about how phages control intracellular infections. With advances in phage genomics and mechanisms of delivery and cell uptake, the development of phage-based antibacterial strategies to address the treatment of intracellular bacteria has general potential. In this review, we present the current state of knowledge regarding the application of bacteriophages against intracellular bacteria. We cover phage deployment against the most common intracellular pathogens with special attention to therapeutic and preventive strategies.
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Affiliation(s)
- Paulina Śliwka
- Department of Biotechnology and Food Microbiology, Faculty of Biotechnology and Food Science, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
| | - Marta Ochocka
- Department of Biotechnology and Food Microbiology, Faculty of Biotechnology and Food Science, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
| | - Aneta Skaradzińska
- Department of Biotechnology and Food Microbiology, Faculty of Biotechnology and Food Science, Wrocław University of Environmental and Life Sciences, Wrocław, Poland
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Host Genome-Wide Association Study of Infant Susceptibility to Shigella-Associated Diarrhea. Infect Immun 2021; 89:IAI.00012-21. [PMID: 33649051 PMCID: PMC8316060 DOI: 10.1128/iai.00012-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 02/22/2021] [Indexed: 12/15/2022] Open
Abstract
Shigella is a leading cause of moderate-to-severe diarrhea globally and the causative agent of shigellosis and bacillary dysentery. Associated with 80 to 165 million cases of diarrhea and >13% of diarrheal deaths, in many regions, Shigella exposure is ubiquitous while infection is heterogenous. To characterize host-genetic susceptibility to Shigella-associated diarrhea, we performed two independent genome-wide association studies (GWAS) including Bangladeshi infants from the PROVIDE and CBC birth cohorts in Dhaka, Bangladesh. Cases were infants with Shigella-associated diarrhea (n = 143) and controls were infants with no Shigella-associated diarrhea in the first 13 months of life (n = 446). Shigella-associated diarrhea was identified via quantitative PCR (qPCR) threshold cycle (CT ) distributions for the ipaH gene, carried by all four Shigella species and enteroinvasive Escherichia coli Host GWAS were performed under an additive genetic model. A joint analysis identified protective loci on chromosomes 11 (rs582240, within the KRT18P59 pseudogene; P = 6.40 × 10-8; odds ratio [OR], 0.43) and 8 (rs12550437, within the lincRNA RP11-115J16.1; P = 1.49 × 10-7; OR, 0.48). Conditional analyses identified two previously suggestive loci, a protective locus on chromosome 7 (rs10266841, within the 3' untranslated region [UTR] of CYTH3; P conditional = 1.48 × 10-7; OR, 0.44) and a risk-associated locus on chromosome 10 (rs2801847, an intronic variant within MPP7; P conditional = 8.37 × 10-8; OR, 5.51). These loci have all been indirectly linked to bacterial type 3 secretion system (T3SS) activity, its components, and bacterial effectors delivered into host cells. Host genetic factors that may affect bacterial T3SS activity and are associated with the host response to Shigella-associated diarrhea may provide insight into vaccine and drug development efforts for Shigella-associated diarrheal disease.
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Nyegue MA, Afagnigni AD, Ndam YN, Djova SV, Fonkoua MC, Etoa FX. Toxicity and Activity of Ethanolic Leaf Extract of Paullinia pinnata Linn (Sapindaceae) in Shigella flexneri-Induced Diarrhea in Wistar Rats. J Evid Based Integr Med 2021; 25:2515690X19900883. [PMID: 31969010 PMCID: PMC6978825 DOI: 10.1177/2515690x19900883] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Herbal products from Paullinia pinnata Linn are widely used in African
folk medicine to treat several infectious diseases. Although the extracts from this plant
has been shown to possess antimicrobial potential, their activity in infectious diarrhea
is less reported. Diarrhea was induced by oral administration of 1.2 × 109
CFU/mL of Shigella flexneri to the rats. The infected rats were treated
for 5 days with the doses of 111.42, 222.84, and 445.68 mg/kg of P
pinnata. The level of biochemical parameters was assessed and histology of
organs examined by 14 days subacute toxicity. S flexneri stool load was
considerably reduced after 4 days of treatment with the dose of 445.68 mg/kg, 5 days at
the dose of 222.84 mg/kg for the extract, and 2 days with ciprofloxacin. The dose of
111.42 mg/kg appeared efficient after 5 days of treatment. The creatinine level increased
at the dose of 445.68 mg/kg in both male and female rats and decrease at the dose of
222.84 mg/mL in female rats while an increase was noted in the male rats. Liver and kidney
histology were modified at the dose of 445.68 mg/kg while no change was observed at the
doses of 111.42 and 222.84 mg/kg. P pinnata leaf extract is efficient
against infectious diarrhea at 111.42 mg/kg without side effect.
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Knowles A, Campbell S, Cross N, Stafford P. Bacterial Manipulation of the Integrated Stress Response: A New Perspective on Infection. Front Microbiol 2021; 12:645161. [PMID: 33967983 PMCID: PMC8100032 DOI: 10.3389/fmicb.2021.645161] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 02/16/2021] [Indexed: 11/13/2022] Open
Abstract
Host immune activation forms a vital line of defence against bacterial pathogenicity. However, just as hosts have evolved immune responses, bacteria have developed means to escape, hijack and subvert these responses to promote survival. In recent years, a highly conserved group of signalling cascades within the host, collectively termed the integrated stress response (ISR), have become increasingly implicated in immune activation during bacterial infection. Activation of the ISR leads to a complex web of cellular reprogramming, which ultimately results in the paradoxical outcomes of either cellular homeostasis or cell death. Therefore, any pathogen with means to manipulate this pathway could induce a range of cellular outcomes and benefit from favourable conditions for long-term survival and replication. This review aims to outline what is currently known about bacterial manipulation of the ISR and present key hypotheses highlighting areas for future research.
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Affiliation(s)
- Alex Knowles
- Biomolecular Sciences Research Centre, Department of Biosciences and Chemistry, Faculty of Health and Wellbeing, Sheffield Hallam University, Sheffield, United Kingdom
| | - Susan Campbell
- Biomolecular Sciences Research Centre, Department of Biosciences and Chemistry, Faculty of Health and Wellbeing, Sheffield Hallam University, Sheffield, United Kingdom
| | - Neil Cross
- Biomolecular Sciences Research Centre, Department of Biosciences and Chemistry, Faculty of Health and Wellbeing, Sheffield Hallam University, Sheffield, United Kingdom
| | - Prachi Stafford
- Biomolecular Sciences Research Centre, Department of Biosciences and Chemistry, Faculty of Health and Wellbeing, Sheffield Hallam University, Sheffield, United Kingdom
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Pakbin B, Didban A, Monfared YK, Mahmoudi R, Peymani A, Modabber MR. Antibiotic susceptibility and genetic relatedness of Shigella species isolated from food and human stool samples in Qazvin, Iran. BMC Res Notes 2021; 14:144. [PMID: 33865447 PMCID: PMC8052664 DOI: 10.1186/s13104-021-05554-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 04/02/2021] [Indexed: 01/25/2023] Open
Abstract
Objective The aim of this study was to investigate the genetic relatedness and antimicrobial resistance among Shigella species isolated from food and stool samples. Using cross sectional study method, Shigella spp. were isolated from food and clinical samples using culture-based, biochemical and serological methods. Antimicrobial susceptibility and genetic relatedness among the isolates were evaluated using disk diffusion and RAPD-PCR methods respectively. Results The prevalence of Shigella spp. were 4.84 and 7.7% in food and stool samples respectively. All food isolates were Sh. sonnei. 91.42% of the Shigella stool isolates were Sh. sonnei. 62.5% of food isolates were resistant to tetracycline. 46.8, 50 and 65.8% of clinical isolates were resistant to imipenem, amikacin and azithromycin respectively. 50 and 85.7% of the food and clinical isolates respectively were MDR. Dendrogram generated by RAPD-PCR showed that the isolates from food and stool samples were categorized in a same group. Close genetic relatedness between MDR Shigella isolates from food and clinical samples indicate that foods can be considered as one of the main vehicles for transmission of MDR Shigella to human causing acute diseases. Survey of MDR Shigella among food and clinical samples is strongly suggested to be implemented.
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Affiliation(s)
- Babak Pakbin
- Children Growth Research Center, Research Institute for Prevention of Non-Communicable Diseases, Qazvin University of Medical Sciences, Bahonar Blvd., P.O. Box: 34185-754, Qazvin, Iran.,Medical Microbiology Research Center, Qazvin University of Medical Sciences, Qazvin, Iran
| | - Abdollah Didban
- Children Growth Research Center, Research Institute for Prevention of Non-Communicable Diseases, Qazvin University of Medical Sciences, Bahonar Blvd., P.O. Box: 34185-754, Qazvin, Iran.
| | | | - Razzagh Mahmoudi
- Medical Microbiology Research Center, Qazvin University of Medical Sciences, Qazvin, Iran
| | - Amir Peymani
- Medical Microbiology Research Center, Qazvin University of Medical Sciences, Qazvin, Iran
| | - Mohammad Reza Modabber
- Medical Microbiology Research Center, Qazvin University of Medical Sciences, Qazvin, Iran
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Roach TG, Lång HKM, Xiong W, Ryhänen SJ, Capelluto DGS. Protein Trafficking or Cell Signaling: A Dilemma for the Adaptor Protein TOM1. Front Cell Dev Biol 2021; 9:643769. [PMID: 33718385 PMCID: PMC7952518 DOI: 10.3389/fcell.2021.643769] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 02/09/2021] [Indexed: 12/29/2022] Open
Abstract
Lysosomal degradation of ubiquitinated transmembrane protein receptors (cargo) relies on the function of Endosomal Sorting Complex Required for Transport (ESCRT) protein complexes. The ESCRT machinery is comprised of five unique oligomeric complexes with distinct functions. Target of Myb1 (TOM1) is an ESCRT protein involved in the initial steps of endosomal cargo sorting. To exert its function, TOM1 associates with ubiquitin moieties on the cargo via its VHS and GAT domains. Several ESCRT proteins, including TOLLIP, Endofin, and Hrs, have been reported to form a complex with TOM1 at early endosomal membrane surfaces, which may potentiate the role of TOM1 in cargo sorting. More recently, it was found that TOM1 is involved in other physiological processes, including autophagy, immune responses, and neuroinflammation, which crosstalk with its endosomal cargo sorting function. Alteration of TOM1 function has emerged as a phosphoinositide-dependent survival mechanism for bacterial infections and cancer progression. Based on current knowledge of TOM1-dependent cellular processes, this review illustrates how TOM1 functions in coordination with an array of protein partners under physiological and pathological scenarios.
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Affiliation(s)
- Tiffany G. Roach
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Fralin Life Sciences Institute, and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, United States
| | - Heljä K. M. Lång
- Division of Hematology, Oncology, and Stem Cell Transplantation, Children’s Hospital, and Pediatric Research Center, The New Children’s Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
- Department of Anatomy and Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Wen Xiong
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Fralin Life Sciences Institute, and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, United States
| | - Samppa J. Ryhänen
- Division of Hematology, Oncology, and Stem Cell Transplantation, Children’s Hospital, and Pediatric Research Center, The New Children’s Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Daniel G. S. Capelluto
- Protein Signaling Domains Laboratory, Department of Biological Sciences, Fralin Life Sciences Institute, and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, United States
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The Shigella Type III Secretion System: An Overview from Top to Bottom. Microorganisms 2021; 9:microorganisms9020451. [PMID: 33671545 PMCID: PMC7926512 DOI: 10.3390/microorganisms9020451] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 02/16/2021] [Accepted: 02/18/2021] [Indexed: 12/16/2022] Open
Abstract
Shigella comprises four species of human-restricted pathogens causing bacillary dysentery. While Shigella possesses multiple genetic loci contributing to virulence, a type III secretion system (T3SS) is its primary virulence factor. The Shigella T3SS nanomachine consists of four major assemblies: the cytoplasmic sorting platform; the envelope-spanning core/basal body; an exposed needle; and a needle-associated tip complex with associated translocon that is inserted into host cell membranes. The initial subversion of host cell activities is carried out by the effector functions of the invasion plasmid antigen (Ipa) translocator proteins, with the cell ultimately being controlled by dedicated effector proteins that are injected into the host cytoplasm though the translocon. Much of the information now available on the T3SS injectisome has been accumulated through collective studies on the T3SS from three systems, those of Shigella flexneri, Salmonella typhimurium and Yersinia enterocolitica/Yersinia pestis. In this review, we will touch upon the important features of the T3SS injectisome that have come to light because of research in the Shigella and closely related systems. We will also briefly highlight some of the strategies being considered to target the Shigella T3SS for disease prevention.
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Alterations in the gut bacterial microbiome in people with type 2 diabetes mellitus and diabetic retinopathy. Sci Rep 2021; 11:2738. [PMID: 33531650 PMCID: PMC7854632 DOI: 10.1038/s41598-021-82538-0] [Citation(s) in RCA: 74] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 01/21/2021] [Indexed: 02/07/2023] Open
Abstract
Gut bacterial microbiome dysbiosis in type 2 Diabetes Mellitus (T2DM) has been reported, but such an association with Diabetic Retinopathy (DR) is not known. We explored possible link between gut bacterial microbiome dysbiosis and DR. Using fecal samples of healthy controls (HC) and people with T2DM with/without DR, gut bacterial communities were analysed using 16S rRNA gene sequencing and data analysed using QIIME and R software. Dysbiosis in the gut microbiomes, at phyla and genera level, was observed in people with T2DM and DR compared to HC. People with DR exhibited greater discrimination from HC. Microbiomes of people with T2DM and DR were also significantly different. Both DM and DR microbiomes showed a decrease in anti-inflammatory, probiotic and other bacteria that could be pathogenic, compared to HC, and the observed change was more pronounced in people with DR. This is the first report demonstrating dysbiosis in the gut microbiome (alteration in the diversity and abundance at the phyla and genera level) in people with DR compared to HC. Such studies would help in developing novel and targeted therapies to improve treatment of DR.
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Maleki A, Moslem MS, Kouhsari E, Pakzad I, Ghafouri Z, Khaghani S, Sadeghifard N. Virulence-associated genes and toxin-antitoxin system genes of Shigella flexneri: Presence and expression in normal and thermal stress conditions. Meta Gene 2021. [DOI: 10.1016/j.mgene.2020.100825] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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35
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Vishwakarma A, Lal R, Ramya M. Aptamer-based approaches for the detection of waterborne pathogens. Int Microbiol 2021; 24:125-140. [PMID: 33404933 DOI: 10.1007/s10123-020-00154-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 10/13/2020] [Accepted: 12/14/2020] [Indexed: 02/06/2023]
Abstract
Waterborne ailments pose a serious threat to public health and are a huge economic burden. Lack of hygiene in drinking and recreational water is the chief source of microbial pathogens in developing countries. Poor water quality and sanitation account for more than 3.4 million deaths a year worldwide. This has urged authorities and researchers to explore different avenues of pathogen detection. There is a growing demand for rapid and reliable sensor technologies, in particular those that can detect in situ and perform in harsh conditions. Some of the major waterborne pathogens include Vibrio cholerae, Leptospira interrogans, Campylobacter jejuni, Shigella spp., enterotoxigenic Escherichia coli, Clostridium difficile, Cryptosporidium parvum, Entamoeba histolytica, and Hepatitis A virus. While conventional methods of pathogen detection like serodiagnosis and microbiological methods have been superseded by nucleic acid amplification methods, there is still potential for improvement. This review provides an insight into aptamers and their utility in the form of aptasensors. It discusses how aptamer-based approaches have emerged as a novel strategy and its advantages over more resource-intensive and complex biochemical approaches.
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Affiliation(s)
- Archana Vishwakarma
- Molecular Genetics Laboratory, Department of Genetic Engineering, College of Engineering and Technology, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur 603203, Kanchipuram, Chennai, TN, India
| | - Roshni Lal
- Molecular Genetics Laboratory, Department of Genetic Engineering, College of Engineering and Technology, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur 603203, Kanchipuram, Chennai, TN, India
| | - Mohandass Ramya
- Molecular Genetics Laboratory, Department of Genetic Engineering, College of Engineering and Technology, SRM Institute of Science and Technology, SRM Nagar, Kattankulathur 603203, Kanchipuram, Chennai, TN, India.
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Hill CL, McCain K, Nyathi ME, Edokpayi JN, Kahler DM, Operario DJ, Taylor DDJ, Wright NC, Smith JA, Guerrant RL, Samie A, Dillingham RA, Bessong PO, Rogawski McQuade ET. Impact of Low-Cost Point-of-Use Water Treatment Technologies on Enteric Infections and Growth among Children in Limpopo, South Africa. Am J Trop Med Hyg 2020; 103:1405-1415. [PMID: 32840201 PMCID: PMC7543807 DOI: 10.4269/ajtmh.20-0228] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Enteric infections early in life have been associated with poor linear growth among children in low-resource settings. Point-of-use water treatment technologies provide effective and low-cost solutions to reduce exposure to enteropathogens from drinking water, but it is unknown whether the use of these technologies translates to improvements in child growth. We conducted a community-based randomized controlled trial of two water treatment technologies to estimate their effects on child growth in Limpopo, South Africa. We randomized 404 households with a child younger than 3 years to receive a silver-impregnated ceramic water filter, a silver-impregnated ceramic tablet, a safe-storage water container alone, or no intervention, and these households were followed up quarterly for 2 years. We estimated the effects of the interventions on linear and ponderal growth, enteric infections assessed by quantitative molecular diagnostics, and diarrhea prevalence. The silver-impregnated ceramic water filters and tablets consistently achieved approximately 1.2 and 3 log reductions, respectively, in total coliform bacteria in drinking water samples. However, the filters and tablets were not associated with differences in height (height-for-age z-score differences compared with no intervention: 0.06, 95% CI: −0.29, 0.40, and 0.00, 95% CI: −0.35, 0.35, respectively). There were also no effects of the interventions on weight, diarrhea prevalence, or enteric infections. Despite their effectiveness in treating drinking water, the use of the silver-impregnated ceramic water filters and tablets did not reduce enteric infections or improve child growth. More transformative water, sanitation, and hygiene interventions that better prevent enteric infections are likely needed to improve long-term child growth outcomes.
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Affiliation(s)
- Courtney L Hill
- Department of Engineering Systems and Environment, University of Virginia, Charlottesville, Virginia
| | - Kelly McCain
- Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, Georgia.,Department of Engineering Systems and Environment, University of Virginia, Charlottesville, Virginia
| | - Mzwakhe E Nyathi
- Department of Animal Science, University of Venda, Thohoyandou, South Africa
| | - Joshua N Edokpayi
- Department of Hydrology and Water Resources Mining and Environmental Geology, University of Venda, Thohoyandou, South Africa
| | - David M Kahler
- Center for Environmental Research and Education, Duquesne University, Pittsburgh, Pennsylvania
| | - Darwin J Operario
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, Virginia
| | - David D J Taylor
- Department of Civil and Mineral Engineering, University of Toronto, Toronto, Canada
| | - Natasha C Wright
- Department of Mechanical Engineering, University of Minnesota Twin Cities, Minneapolis, Minnesota
| | - James A Smith
- Department of Engineering Systems and Environment, University of Virginia, Charlottesville, Virginia
| | - Richard L Guerrant
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, Virginia
| | - Amidou Samie
- Department of Microbiology, University of Venda, Thohoyandou, South Africa
| | - Rebecca A Dillingham
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, Virginia
| | - Pascal O Bessong
- Department of Microbiology, University of Venda, Thohoyandou, South Africa
| | - Elizabeth T Rogawski McQuade
- Department of Public Health Sciences, University of Virginia, Charlottesville, Virginia.,Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, Virginia
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Ranganathan S, Smith EM, Foulke-Abel JD, Barry EM. Research in a time of enteroids and organoids: how the human gut model has transformed the study of enteric bacterial pathogens. Gut Microbes 2020; 12:1795492. [PMID: 32795243 PMCID: PMC7524385 DOI: 10.1080/19490976.2020.1795389] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 06/29/2020] [Accepted: 07/01/2020] [Indexed: 02/03/2023] Open
Abstract
Enteric bacterial pathogens cause significant morbidity and mortality globally. Studies in tissue culture and animal models shaped our initial understanding of these host-pathogen interactions. However, intrinsic shortcomings in these models limit their application, especially in translational applications like drug screening and vaccine development. Human intestinal enteroid and organoid models overcome some limitations of existing models and advance the study of enteric pathogens. In this review, we detail the use of human enteroids and organoids to investigate the pathogenesis of invasive bacteria Shigella, Listeria, and Salmonella, and noninvasive bacteria pathogenic Escherichia coli, Clostridium difficile, and Vibrio cholerae. We highlight how these studies confirm previously identified mechanisms and, importantly, reveal novel ones. We also discuss the challenges for model advancement, including platform engineering to integrate environmental conditions, innate immune cells and the resident microbiome, and the potential for pre-clinical testing of recently developed antimicrobial drugs and vaccines.
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Affiliation(s)
- Sridevi Ranganathan
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Emily M. Smith
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Jennifer D. Foulke-Abel
- Department of Medicine, Division of Gastroenterology and Hepatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Eileen M. Barry
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA
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Shigella sonnei: virulence and antibiotic resistance. Arch Microbiol 2020; 203:45-58. [PMID: 32929595 PMCID: PMC7489455 DOI: 10.1007/s00203-020-02034-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 08/27/2020] [Accepted: 09/02/2020] [Indexed: 12/21/2022]
Abstract
Shigella sonnei is the emerging pathogen globally, as it is the second common infectious species of shigellosis (bloody diarrhoea) in low- and middle-income countries (LMICs) and the leading one in developed world. The multifactorial processes and novel mechanisms have been identified in S. sonnei, that are collectively playing apart a substantial role in increasing its prevalence, while replacing the S. flexneri and other Gram-negative gut pathogens niche occupancy. Recently, studies suggest that due to improvement in sanitation S. sonnei has reduced cross-immunization from Plesiomonas shigelliodes (having same O-antigen as S. sonnei) and also found to outcompete the two major species of Enterobacteriaceae family (Shigella flexneri and Escherichia coli), due to encoding of type VI secretion system (T6SS). This review aimed to highlight S. sonnei as an emerging pathogen in the light of recent research with pondering aspects on its epidemiology, transmission, and pathogenic mechanisms. Additionally, this paper aimed to review S. sonnei disease pattern and related complications, symptoms, and laboratory diagnostic techniques. Furthermore, the available treatment reigns and antibiotic-resistance patterns of S. sonnei are also discussed, as the ciprofloxacin and fluoroquinolone-resistant S. sonnei has already intensified the global spread and burden of antimicrobial resistance. In last, prevention and controlling strategies are briefed to limit and tackle S. sonnei and possible future areas are also explored that needed more research to unravel the hidden mysteries surrounding S. sonnei.
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Newly Emerged Serotype 1c of Shigella flexneri: Multiple Origins and Changing Drug Resistance Landscape. Genes (Basel) 2020; 11:genes11091042. [PMID: 32899396 PMCID: PMC7565858 DOI: 10.3390/genes11091042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 08/31/2020] [Accepted: 09/01/2020] [Indexed: 12/04/2022] Open
Abstract
Bacillary dysentery caused by Shigella flexneri is a major cause of under-five mortality in developing countries, where a novel S. flexneri serotype 1c has become very common since the 1980s. However, the origin and diversification of serotype 1c remain poorly understood. To understand the evolution of serotype 1c and their antimicrobial resistance, we sequenced and analyzed the whole-genome of 85 clinical isolates from the United Kingdom, Egypt, Bangladesh, Vietnam, and Japan belonging to serotype 1c and related serotypes of 1a, 1b and Y/Yv. We identified up to three distinct O-antigen modifying genes in S. flexneri 1c strains, which were acquired from three different bacteriophages. Our analysis shows that S. flexneri 1c strains have originated from serotype 1a and serotype 1b strains after the acquisition of bacteriophage-encoding gtrIc operon. The maximum-likelihood phylogenetic analysis using core genes suggests two distinct S. flexneri 1c lineages, one specific to Bangladesh, which originated from ancestral serotype 1a strains and the other from the United Kingdom, Egypt, and Vietnam originated from ancestral serotype 1b strains. We also identified 63 isolates containing multiple drug-resistant genes in them conferring resistance against streptomycin, sulfonamide, quinolone, trimethoprim, tetracycline, chloramphenicol, and beta-lactamase. Furthermore, antibiotic susceptibility assays showed 83 (97.6%) isolates as either complete or intermediate resistance to the WHO-recommended first- and second-line drugs. This changing drug resistance pattern demonstrates the urgent need for drug resistance surveillance and renewed treatment guidelines.
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Whelan R, McVicker G, Leo JC. Staying out or Going in? The Interplay between Type 3 and Type 5 Secretion Systems in Adhesion and Invasion of Enterobacterial Pathogens. Int J Mol Sci 2020; 21:E4102. [PMID: 32521829 PMCID: PMC7312957 DOI: 10.3390/ijms21114102] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 06/03/2020] [Accepted: 06/05/2020] [Indexed: 12/12/2022] Open
Abstract
Enteric pathogens rely on a variety of toxins, adhesins and other virulence factors to cause infections. Some of the best studied pathogens belong to the Enterobacterales order; these include enteropathogenic and enterohemorrhagic Escherichia coli, Shigella spp., and the enteropathogenic Yersiniae. The pathogenesis of these organisms involves two different secretion systems, a type 3 secretion system (T3SS) and type 5 secretion systems (T5SSs). The T3SS forms a syringe-like structure spanning both bacterial membranes and the host cell plasma membrane that translocates toxic effector proteins into the cytoplasm of the host cell. T5SSs are also known as autotransporters, and they export part of their own polypeptide to the bacterial cell surface where it exerts its function, such as adhesion to host cell receptors. During infection with these enteropathogens, the T3SS and T5SS act in concert to bring about rearrangements of the host cell cytoskeleton, either to invade the cell, confer intracellular motility, evade phagocytosis or produce novel structures to shelter the bacteria. Thus, in these bacteria, not only the T3SS effectors but also T5SS proteins could be considered "cytoskeletoxins" that bring about profound alterations in host cell cytoskeletal dynamics and lead to pathogenic outcomes.
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Affiliation(s)
| | | | - Jack C. Leo
- Antimicrobial Resistance, Omics and Microbiota Group, Department of Biosciences, Nottingham Trent University, Nottingham NG1 4FQ, UK; (R.W.); (G.M.)
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Arunasri K, Mahesh M, Sai Prashanthi G, Jayasudha R, Kalyana Chakravarthy S, Tyagi M, Pappuru RR, Shivaji S. Comparison of the Vitreous Fluid Bacterial Microbiomes between Individuals with Post Fever Retinitis and Healthy Controls. Microorganisms 2020; 8:E751. [PMID: 32429503 PMCID: PMC7285296 DOI: 10.3390/microorganisms8050751] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 04/23/2020] [Accepted: 05/04/2020] [Indexed: 12/21/2022] Open
Abstract
Ocular microbiome research has gained momentum in the recent past and has provided new insights into health and disease conditions. However, studies on sight threatening intraocular inflammatory diseases have remained untouched. In the present study, we attempted to identify the bacterial microbiome associated with post fever retinitis using a metagenomic sequencing approach. For this purpose, bacterial ocular microbiomes were generated from vitreous samples collected from control individuals (VC, n = 19) and individuals with post fever retinitis (PFR, n = 9), and analysed. The results revealed 18 discriminative genera in the microbiomes of the two cohorts out of which 16 genera were enriched in VC and the remaining two in PFR group. These discriminative genera were inferred to have antimicrobial, anti-inflammatory, and probiotic function. Only two pathogenic bacteria were differentially abundant in 20% of the PFR samples. PCoA and heatmap analysis showed that the vitreous microbiomes of VC and PFR formed two distinct clusters indicating dysbiosis in the vitreous bacterial microbiomes. Functional assignments and network analysis also revealed that the vitreous bacterial microbiomes in the control group exhibited more evenness in the bacterial diversity and several bacteria had antimicrobial function compared to the PFR group.
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Affiliation(s)
- Kotakonda Arunasri
- Jhaveri Microbiology Centre, Prof Brien Holden Eye Research Centre, L V Prasad Eye Institute, L V Prasad Marg, Banjara Hills, Hyderabad 500034, India; (K.A.); (M.M.); (G.S.P.); (R.J.); (S.K.C.)
| | - Malleswarapu Mahesh
- Jhaveri Microbiology Centre, Prof Brien Holden Eye Research Centre, L V Prasad Eye Institute, L V Prasad Marg, Banjara Hills, Hyderabad 500034, India; (K.A.); (M.M.); (G.S.P.); (R.J.); (S.K.C.)
| | - Gumpili Sai Prashanthi
- Jhaveri Microbiology Centre, Prof Brien Holden Eye Research Centre, L V Prasad Eye Institute, L V Prasad Marg, Banjara Hills, Hyderabad 500034, India; (K.A.); (M.M.); (G.S.P.); (R.J.); (S.K.C.)
| | - Rajagopalaboopathi Jayasudha
- Jhaveri Microbiology Centre, Prof Brien Holden Eye Research Centre, L V Prasad Eye Institute, L V Prasad Marg, Banjara Hills, Hyderabad 500034, India; (K.A.); (M.M.); (G.S.P.); (R.J.); (S.K.C.)
| | - Sama Kalyana Chakravarthy
- Jhaveri Microbiology Centre, Prof Brien Holden Eye Research Centre, L V Prasad Eye Institute, L V Prasad Marg, Banjara Hills, Hyderabad 500034, India; (K.A.); (M.M.); (G.S.P.); (R.J.); (S.K.C.)
| | - Mudit Tyagi
- Smt. Kanuri Santhamma Centre for Vitreo Retinal Diseases, L V Prasad Eye Institute, L V Prasad Marg, Banjara Hills, Hyderabad 500034, India; (M.T.); (R.R.P.)
| | - Rajeev R. Pappuru
- Smt. Kanuri Santhamma Centre for Vitreo Retinal Diseases, L V Prasad Eye Institute, L V Prasad Marg, Banjara Hills, Hyderabad 500034, India; (M.T.); (R.R.P.)
| | - Sisinthy Shivaji
- Jhaveri Microbiology Centre, Prof Brien Holden Eye Research Centre, L V Prasad Eye Institute, L V Prasad Marg, Banjara Hills, Hyderabad 500034, India; (K.A.); (M.M.); (G.S.P.); (R.J.); (S.K.C.)
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42
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Walpole GFW, Grinstein S. Endocytosis and the internalization of pathogenic organisms: focus on phosphoinositides. F1000Res 2020; 9. [PMID: 32494357 PMCID: PMC7233180 DOI: 10.12688/f1000research.22393.1] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/07/2020] [Indexed: 12/18/2022] Open
Abstract
Despite their comparatively low abundance in biological membranes, phosphoinositides are key to the regulation of a diverse array of signaling pathways and direct membrane traffic. The role of phosphoinositides in the initiation and progression of endocytic pathways has been studied in considerable depth. Recent advances have revealed that distinct phosphoinositide species feature prominently in clathrin-dependent and -independent endocytosis as well as in phagocytosis and macropinocytosis. Moreover, a variety of intracellular and cell-associated pathogens have developed strategies to commandeer host cell phosphoinositide metabolism to gain entry and/or metabolic advantage, thereby promoting their survival and proliferation. Here, we briefly survey the current knowledge on the involvement of phosphoinositides in endocytosis, phagocytosis, and macropinocytosis and highlight several examples of molecular mimicry employed by pathogens to either “hitch a ride” on endocytic pathways endogenous to the host or create an entry path of their own.
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Affiliation(s)
- Glenn F W Walpole
- Program in Cell Biology, Hospital for Sick Children, Toronto, ON, Canada.,Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Sergio Grinstein
- Program in Cell Biology, Hospital for Sick Children, Toronto, ON, Canada.,Department of Biochemistry, University of Toronto, Toronto, ON, Canada.,Keenan Research Centre of the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada
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43
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Mukherjee T, Udupa VAV, Prakhar P, Chandra K, Chakravortty D, Balaji KN. Epidermal Growth Factor Receptor-Responsive Indoleamine 2,3-Dioxygenase Confers Immune Homeostasis During Shigella flexneri Infection. J Infect Dis 2020; 219:1841-1851. [PMID: 30615126 DOI: 10.1093/infdis/jiz009] [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: 08/27/2018] [Accepted: 01/05/2019] [Indexed: 12/19/2022] Open
Abstract
The resolution of Shigella flexneri infection-associated hyperinflammation is crucial for host survival. Using in vitro and in vivo models of shigellosis, we found that S. flexneri induces the expression of indoleamine 2,3-dioxygenase 1 (IDO1) through the nucleotide oligomerization domain 2 (NOD2) and epidermal growth factor receptor (EGFR) signaling pathway. Congruently, abrogation of NOD2 or EGFR compromises the ability of S. flexneri to induce IDO1 expression. We observed that the loss of IDO1 function in vivo exacerbates shigellosis by skewing the inflammatory cytokine response, disrupting colon epithelial barrier integrity and consequently limiting the host life-span. Interestingly, administration of recombinant EGF rescued mice from IDO1 inhibition-driven aggravated shigellosis by restoring the cytokine balance and subsequently restricting bacterial growth. This is the first study that underscores the direct implication of the NOD2-EGFR axis in IDO1 production and its crucial homeostatic contributions during shigellosis. Together, these findings reveal EGF as a potential therapeutic intervention for infectious diseases.
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Affiliation(s)
- Tanushree Mukherjee
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India
| | - Vibha A V Udupa
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India
| | - Praveen Prakhar
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India
| | - Kasturi Chandra
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India
| | - Dipshikha Chakravortty
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore, India
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Samassa F, Ferrari ML, Husson J, Mikhailova A, Porat Z, Sidaner F, Brunner K, Teo TH, Frigimelica E, Tinevez JY, Sansonetti PJ, Thoulouze MI, Phalipon A. Shigella impairs human T lymphocyte responsiveness by hijacking actin cytoskeleton dynamics and T cell receptor vesicular trafficking. Cell Microbiol 2020; 22:e13166. [PMID: 31957253 PMCID: PMC7187243 DOI: 10.1111/cmi.13166] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 12/18/2019] [Accepted: 12/18/2019] [Indexed: 12/12/2022]
Abstract
Strategies employed by pathogenic enteric bacteria, such as Shigella, to subvert the host adaptive immunity are not well defined. Impairment of T lymphocyte chemotaxis by blockage of polarised edge formation has been reported upon Shigella infection. However, the functional impact of Shigella on T lymphocytes remains to be determined. Here, we show that Shigella modulates CD4+ T cell F‐actin dynamics and increases cell cortical stiffness. The scanning ability of T lymphocytes when encountering antigen‐presenting cells (APC) is subsequently impaired resulting in decreased cell–cell contacts (or conjugates) between the two cell types, as compared with non‐infected T cells. In addition, the few conjugates established between the invaded T cells and APCs display no polarised delivery and accumulation of the T cell receptor to the contact zone characterising canonical immunological synapses. This is most likely due to the targeting of intracellular vesicular trafficking by the bacterial type III secretion system (T3SS) effectors IpaJ and VirA. The collective impact of these cellular reshapings by Shigella eventually results in T cell activation dampening. Altogether, these results highlight the combined action of T3SS effectors leading to T cell defects upon Shigella infection.
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Affiliation(s)
- Fatoumata Samassa
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, INSERM U1202, Paris, France
| | - Mariana L Ferrari
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, INSERM U1202, Paris, France
| | - Julien Husson
- Laboratoire d'Hydrodynamique (LadHyX), Ecole polytechnique, CNRS, Institut Polytechnique de Paris, Palaiseau, France
| | | | - Ziv Porat
- Flow Cytometry Unit, Life Sciences Core Facility, Weizmann Institute of Sciences, Rehovot, Israel
| | | | - Katja Brunner
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, INSERM U1202, Paris, France
| | - Teck-Hui Teo
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, INSERM U1202, Paris, France
| | | | | | - Philippe J Sansonetti
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, INSERM U1202, Paris, France.,Chaire de Microbiologie et Maladies Infectieuses, Collège de France, Paris, France
| | | | - Armelle Phalipon
- Molecular Microbial Pathogenesis Unit, Institut Pasteur, INSERM U1202, Paris, France
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45
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Leow CY, Kazi A, Hisyam Ismail CMK, Chuah C, Lim BH, Leow CH, Banga Singh KK. Reverse vaccinology approach for the identification and characterization of outer membrane proteins of Shigella flexneri as potential cellular- and antibody-dependent vaccine candidates. Clin Exp Vaccine Res 2020; 9:15-25. [PMID: 32095437 PMCID: PMC7024733 DOI: 10.7774/cevr.2020.9.1.15] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 01/30/2020] [Indexed: 11/16/2022] Open
Abstract
Purpose In the developing world, bacillary dysentery is one of the most common communicable diarrheal infections. There are approximately 169 million cases of shigellosis reported worldwide. The disease is transmitted by a group of Gram-negative intracellular enterobacteria known as Shigella flexneri, S. sonnei, S. dysenteriae, and S. boydii. Conventional treatment regimens for Shigella have been less effective due to the development of resistant strains against antibiotics. Therefore, an effective vaccine for the long term control of Shigella transmission is urgently needed. Materials and Methods In this study, a reverse vaccinology approach was employed to identify most conserved and immunogenic outer membrane proteins (OMPs) of S. flexneri 2a. Results Five OMPs including fepA, ompC, nlpD_1, tolC, and nlpD_2 were identified as potential vaccine candidates. Protein-protein interactions analysis using STRING software (https://string-db.org/) revealed that five of these OMPs may potentially interact with other intracellular proteins which are involved in beta-lactam resistance pathway. B- and T-cell epitopes of the selected OMPs were predicted using BCPred as well as Propred I and Propred (http://crdd.osdd.net/raghava/propred/), respectively. Each of these OMPs contains regions which are capable to induce B- and T-cell immune responses. Conclusion Analysis acquired from this study showed that five selected OMPs have great potential for vaccine development against S. flexneri infection. The predicted immunogenic epitopes can also be used for development of peptide vaccines or multi-epitope vaccines against human shigellosis. Reverse vaccinology is a promising strategy for the discovery of potential vaccine candidates which can be used for future vaccine development against global persistent infections.
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Affiliation(s)
- Chiuan Yee Leow
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Kubang Kerian, Malaysia
| | - Ada Kazi
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Kubang Kerian, Malaysia
| | | | - Candy Chuah
- School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Malaysia
| | - Boon Huat Lim
- School of Health Sciences, Universiti Sains Malaysia, Kubang Kerian, Malaysia
| | - Chiuan Herng Leow
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Gelugor, Malaysia
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46
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Tran ENH, Day CJ, Poole J, Jennings MP, Morona R. Specific blood group antibodies inhibit Shigella flexneri interaction with human cells in the absence of spinoculation. Biochem Biophys Res Commun 2019; 521:131-136. [PMID: 31630794 DOI: 10.1016/j.bbrc.2019.10.091] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 10/10/2019] [Indexed: 10/25/2022]
Abstract
The classical models of investigating Shigella flexneri adherence and invasion of tissue culture cells involve either bacterial centrifugation (spinoculation) or the use of AfaE adhesin to overcome the low infection rate observed in vitro. However clinically, S. flexneri clearly adheres and invades the human colon in the absence of 'spinoculation'. Additionally, certain S. flexneri tissue cell based assays (e.g. plaque assays and infection of T84 epithelial cells on Transwells®), do not require spinoculation. In the absence of spinoculation, we recently showed that glycan-glycan interactions play an important role in S. flexneri interaction with host cells, and that in particular the S. flexneri 2a lipopolysaccharide O antigen glycan has a high affinity for the blood group A glycan. During the investigation of the effect of blood group A antibodies on S. flexneri interaction with cells, we discovered that Panc-1 cells exhibited a high rate of infection in the absence of spinoculation. Select blood group A antibodies inhibited invasion of Panc-1 cells, and adherence to T84 cells. The use of Panc-1 cells represents a simplified model to study S. flexneri pathogenesis and does not require either spinoculation or exogenous adhesins.
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Affiliation(s)
- Elizabeth Ngoc Hoa Tran
- School of Biological Sciences, Department of Molecular & Biomedical Science, Research Centre for Infectious Diseases, University of Adelaide, Adelaide, 5005, Australia
| | - Christopher J Day
- Institute for Glycomics, Griffith University Gold Coast Campus, Queensland, 4222, Australia
| | - Jessica Poole
- Institute for Glycomics, Griffith University Gold Coast Campus, Queensland, 4222, Australia
| | - Michael P Jennings
- Institute for Glycomics, Griffith University Gold Coast Campus, Queensland, 4222, Australia
| | - Renato Morona
- School of Biological Sciences, Department of Molecular & Biomedical Science, Research Centre for Infectious Diseases, University of Adelaide, Adelaide, 5005, Australia.
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Khademi F, Sahebkar A. Fluoroquinolones-resistant Shigella species in Iranian children: a meta-analysis. World J Pediatr 2019; 15:441-453. [PMID: 31154582 DOI: 10.1007/s12519-019-00263-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 04/29/2019] [Indexed: 11/24/2022]
Abstract
BACKGROUND Shigella is one of the most common causes of childhood dysentery along with high rate of morbidity and mortality in both developing and developed countries. According to the World Health Organization (WHO) reports, the prevalence of fluoroquinolones-resistant Shigella species is increasing worldwide which can cause treatment failure of Shigella infections. Since there has not been any comprehensive information on drug-resistant Shigella species in Iran, we conducted the following meta-analysis to raise awareness. METHODS We conducted a literature search on antibiotic resistance of Shigella species to collect published studies in Iran using national and international databases. Literature search was performed by up to Jan 30, 2019 and eligible studies were included in the meta-analysis by predefined criteria. RESULTS Antimicrobial susceptibility testing using disk diffusion technique was the only used method in all included studies. Antibiotic resistance characteristics of Shigella species against WHO recommended therapeutic regimens were as follows: S. dysenteriae 7%, S. flexneri 3.8%, S. boydii 6.9% and S. sonnei 2.6% to ciprofloxacin, S. dysenteriae 27.9%, S. flexneri 19.3%, S. boydii 15.7% and S. sonnei 9.5% to ceftriaxone and also S. dysenteriae 91.7%, S. flexneri 20.7%, S. boydii 46.7% and S. sonnei 32.3% to azithromycin. Resistance to pivmecillinam has not been investigated in Iran. CONCLUSIONS Our findings revealed that ciprofloxacin can still be used as the first-line antibiotic for Shigella infections in Iranian children. However, it seems that second-line antibiotics i.e., ceftriaxone and azithromycin are not good choices for treatment and thus not recommended.
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Affiliation(s)
- Farzad Khademi
- Department of Microbiology, School of Medicine, Ardabil University of Medical Sciences, Daneshgah Street, Ardabil, 5618985991, Iran.
| | - Amirhossein Sahebkar
- Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran.,Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.,School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
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Demler HJ, Case HB, Morales Y, Bernard AR, Johnson SJ, Dickenson NE. Interfacial amino acids support Spa47 oligomerization and shigella type three secretion system activation. Proteins 2019; 87:931-942. [PMID: 31162724 DOI: 10.1002/prot.25754] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 05/23/2019] [Accepted: 05/30/2019] [Indexed: 12/31/2022]
Abstract
Like many Gram-negative pathogens, Shigella rely on a type three secretion system (T3SS) for injection of effector proteins directly into eukaryotic host cells to initiate and sustain infection. Protein secretion through the needle-like type three secretion apparatus (T3SA) requires ATP hydrolysis by the T3SS ATPase Spa47, making it a likely target for in vivo regulation of T3SS activity and an attractive target for small molecule therapeutics against shigellosis. Here, we developed a model of an activated Spa47 homo-hexamer, identifying two distinct regions at each protomer interface that we hypothesized to provide intermolecular interactions supporting Spa47 oligomerization and enzymatic activation. Mutational analysis and a series of high-resolution crystal structures confirm the importance of these residues, as many of the engineered mutants are unable to form oligomers and efficiently hydrolyze ATP in vitro. Furthermore, in vivo evaluation of Shigella virulence phenotype uncovered a strong correlation between T3SS effector protein secretion, host cell membrane disruption, and cellular invasion by the tested mutant strains, suggesting that perturbation of the identified interfacial residues/interactions influences Spa47 activity through preventing oligomer formation, which in turn regulates Shigella virulence. The most impactful mutations are observed within the conserved Site 2 interface where the native residues support oligomerization and likely contribute to a complex hydrogen bonding network that organizes the active site and supports catalysis. The critical reliance on these conserved residues suggests that aspects of T3SS regulation may also be conserved, providing promise for the development of a cross-species therapeutic that broadly targets T3SS ATPase oligomerization and activation.
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Affiliation(s)
- Hannah J Demler
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah
| | - Heather B Case
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah
| | - Yalemi Morales
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah
| | - Abram R Bernard
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah
| | - Sean J Johnson
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah
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49
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Abstract
Septins are widely recognized as a component of the cytoskeleton that is essential for cell division, and new work has shown that septins can recognise cell shape by assembling into filaments on membrane regions that display micrometer-scale curvature (e.g. at the cytokinetic furrow). Moreover, infection biology studies have illuminated important roles for septins in mediating the outcome of host-microbe interactions. In this Review, we discuss a selection of mechanistic insights recently gained from studying three infection paradigms: the rice blast fungus Magnaporthe oryzae, the poxvirus family member vaccinia virus and the Gram-negative bacterium Shigella flexneri These studies have respectively discovered that higher-order septin assemblies enable fungal invasion into plant cells, entrap viral particles at the plasma membrane and recognize dividing bacterial cells for delivery to lysosomes. Collectively, these insights illustrate how studying septin biology during microbial infection can provide fundamental advances in both cell and infection biology, and suggest new concepts underlying infection control.
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Affiliation(s)
- Hoan Van Ngo
- Department of Immunology & Infection, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UK
| | - Serge Mostowy
- Department of Immunology & Infection, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UK
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50
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Parajuli P, Rajput MI, Verma NK. Plasmids of Shigella flexneri serotype 1c strain Y394 provide advantages to bacteria in the host. BMC Microbiol 2019; 19:86. [PMID: 31035948 PMCID: PMC6489325 DOI: 10.1186/s12866-019-1455-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 04/11/2019] [Indexed: 11/29/2022] Open
Abstract
Background Shigella flexneri has an extremely complex genome with a significant number of virulence traits acquired by mobile genetic elements including bacteriophages and plasmids. S. flexneri serotype 1c is an emerging etiological agent of bacillary dysentery in developing countries. In this study, the complete nucleotide sequence of two plasmids of S. flexneri serotype 1c strain Y394 was determined and analysed. Results The plasmid pINV-Y394 is an invasive or virulence plasmid of size 221,293 bp composed of a large number of insertion sequences (IS), virulence genes, regulatory and maintenance genes. Three hundred and twenty-eight open reading frames (ORFs) were identified in pINV-Y394, of which about a half (159 ORFs) were identified as IS elements. Ninety-seven ORFs were related to characterized genes (majority of which are associated with virulence and their regulons), and 72 ORFs were uncharacterized or hypothetical genes. The second plasmid pNV-Y394 is of size 10,866 bp and encodes genes conferring resistance against multiple antibiotics of clinical importance. The multidrug resistance gene cassette consists of tetracycline resistance gene tetA, streptomycin resistance gene strA-strB and sulfonamide-resistant dihydropteroate synthase gene sul2. Conclusions These two plasmids together play a key role in the fitness of Y394 in the host environment. The findings from this study indicate that the pathogenic S. flexneri is a highly niche adaptive pathogen which is able to co-evolve with its host and respond to the selection pressure in its environment. Electronic supplementary material The online version of this article (10.1186/s12866-019-1455-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Pawan Parajuli
- Division of Biomedical Science and Biochemistry, Research School of Biology, The Australian National University, Canberra, ACT, Australia
| | - Munazza I Rajput
- Division of Biomedical Science and Biochemistry, Research School of Biology, The Australian National University, Canberra, ACT, Australia
| | - Naresh K Verma
- Division of Biomedical Science and Biochemistry, Research School of Biology, The Australian National University, Canberra, ACT, Australia.
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