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Johnston EL, Guy-Von Stieglitz S, Zavan L, Cross J, Greening DW, Hill AF, Kaparakis-Liaskos M. The effect of altered pH growth conditions on the production, composition, and proteomes of Helicobacter pylori outer membrane vesicles. Proteomics 2024; 24:e2300269. [PMID: 37991474 DOI: 10.1002/pmic.202300269] [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: 06/30/2023] [Revised: 10/03/2023] [Accepted: 10/16/2023] [Indexed: 11/23/2023]
Abstract
Gram-negative bacteria release outer membrane vesicles (OMVs) that contain cargo derived from their parent bacteria. Helicobacter pylori is a Gram-negative human pathogen that produces urease to increase the pH of the surrounding environment to facilitate colonization of the gastric mucosa. However, the effect of acidic growth conditions on the production and composition of H. pylori OMVs is unknown. In this study, we examined the production, composition, and proteome of H. pylori OMVs produced during acidic and neutral pH growth conditions. H. pylori growth in acidic conditions reduced the quantity and size of OMVs produced. Additionally, OMVs produced during acidic growth conditions had increased protein, DNA, and RNA cargo compared to OMVs produced during neutral conditions. Proteomic analysis comparing the proteomes of OMVs to their parent bacteria demonstrated significant differences in the enrichment of beta-lactamases and outer membrane proteins between bacteria and OMVs, supporting that differing growth conditions impacts OMV composition. We also identified differences in the enrichment of proteins between OMVs produced during different pH growth conditions. Overall, our findings reveal that growth of H. pylori at different pH levels is a factor that alters OMV proteomes, which may affect their subsequent functions.
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Affiliation(s)
- Ella L Johnston
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Bundoora, Australia
- Research Centre for Extracellular Vesicles, La Trobe University, Bundoora, Australia
| | - Sebastian Guy-Von Stieglitz
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Bundoora, Australia
- Research Centre for Extracellular Vesicles, La Trobe University, Bundoora, Australia
| | - Lauren Zavan
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Bundoora, Australia
- Research Centre for Extracellular Vesicles, La Trobe University, Bundoora, Australia
| | - Jonathon Cross
- Baker Heart and Diabetes Institute, Melbourne, Australia
- Baker Department of Cardiometabolic Health, University of Melbourne, Melbourne, Australia
| | - David W Greening
- Research Centre for Extracellular Vesicles, La Trobe University, Bundoora, Australia
- Baker Heart and Diabetes Institute, Melbourne, Australia
- Baker Department of Cardiometabolic Health, University of Melbourne, Melbourne, Australia
| | - Andrew F Hill
- Research Centre for Extracellular Vesicles, La Trobe University, Bundoora, Australia
- Department of Biochemistry and Chemistry, School of Agriculture, Biomedicine and Environment, La Trobe University, Bundoora, Australia
- Institute for Health and Sport, Victoria University, Melbourne, Victoria, Australia
| | - Maria Kaparakis-Liaskos
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Bundoora, Australia
- Research Centre for Extracellular Vesicles, La Trobe University, Bundoora, Australia
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2
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McClain MS, Boeglin WE, Algood HMS, Brash AR. Fatty acids of Helicobacter pylori lipoproteins CagT and Lpp20. Microbiol Spectr 2024; 12:e0047024. [PMID: 38501821 PMCID: PMC11064636 DOI: 10.1128/spectrum.00470-24] [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: 02/24/2024] [Accepted: 03/04/2024] [Indexed: 03/20/2024] Open
Abstract
Bacterial lipoproteins are post-translationally modified by the addition of acyl chains that anchor the protein to bacterial membranes. This modification includes two ester-linked and one amide-linked acyl chain on lipoproteins from Gram-negative bacteria. Helicobacter pylori lipoproteins have important functions in pathogenesis (including delivering the CagA oncoprotein to mammalian cells) and are recognized by host innate and adaptive immune systems. The number and variety of acyl chains on lipoproteins impact the innate immune response through Toll-like receptor 2. The acyl chains added to lipoproteins are derived from membrane phospholipids. H. pylori membrane phospholipids have previously been shown to consist primarily of C14:0 and C19:0 cyclopropane-containing acyl chains. However, the acyl composition of H. pylori lipoproteins has not been determined. In this study, we characterized the acyl composition of two representative H. pylori lipoproteins, Lpp20 and CagT. Fatty acid methyl esters were prepared from both purified lipoproteins and analyzed by gas chromatography-mass spectrometry. For comparison, we also analyzed H. pylori phospholipids. Consistent with previous studies, we observed that the H. pylori phospholipids contain primarily C14:0 and C19:0 cyclopropane-containing fatty acids. In contrast, both the ester-linked and amide-linked fatty acids found in H. pylori lipoproteins were observed to be almost exclusively C16:0 and C18:0. A discrepancy between the acyl composition of membrane phospholipids and lipoproteins as reported here for H. pylori has been previously reported in other bacteria including Borrelia and Brucella. We discuss possible mechanisms.IMPORTANCEColonization of the stomach by Helicobacter pylori is an important risk factor in the development of gastric cancer, the third leading cause of cancer-related death worldwide. H. pylori persists in the stomach despite an immune response against the bacteria. Recognition of lipoproteins by TLR2 contributes to the innate immune response to H. pylori. However, the role of H. pylori lipoproteins in bacterial persistence is poorly understood. As the host response to lipoproteins depends on the acyl chain content, defining the acyl composition of H. pylori lipoproteins is an important step in characterizing how lipoproteins contribute to persistence.
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Affiliation(s)
- Mark S. McClain
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection Immunology and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - William E. Boeglin
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Holly M. Scott Algood
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection Immunology and Inflammation, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Vanderbilt Center for Immunobiology, Vanderbilt Medical Center, Nashville, Tennessee, USA
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee, USA
| | - Alan R. Brash
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
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Bhattacharjee A, Sahoo OS, Sarkar A, Bhattacharya S, Chowdhury R, Kar S, Mukherjee O. Infiltration to infection: key virulence players of Helicobacter pylori pathogenicity. Infection 2024; 52:345-384. [PMID: 38270780 DOI: 10.1007/s15010-023-02159-9] [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: 09/08/2023] [Accepted: 12/13/2023] [Indexed: 01/26/2024]
Abstract
PURPOSE This study aims to comprehensively review the multifaceted factors underlying the successful colonization and infection process of Helicobacter pylori (H. pylori), a prominent Gram-negative pathogen in humans. The focus is on elucidating the functions, mechanisms, genetic regulation, and potential cross-interactions of these elements. METHODS Employing a literature review approach, this study examines the intricate interactions between H. pylori and its host. It delves into virulence factors like VacA, CagA, DupA, Urease, along with phase variable genes, such as babA, babC, hopZ, etc., giving insights about the bacterial perspective of the infection The association of these factors with the infection has also been added in the form of statistical data via Funnel and Forest plots, citing the potential of the virulence and also adding an aspect of geographical biasness to the virulence factors. The biochemical characteristics and clinical relevance of these factors and their effects on host cells are individually examined, both comprehensively and statistically. RESULTS H. pylori is a Gram-negative, spiral bacterium that successfully colonises the stomach of more than half of the world's population, causing peptic ulcers, gastric cancer, MALT lymphoma, and other gastro-duodenal disorders. The clinical outcomes of H. pylori infection are influenced by a complex interplay between virulence factors and phase variable genes produced by the infecting strain and the host genetic background. A meta-analysis of the prevalence of all the major virulence factors has also been appended. CONCLUSION This study illuminates the diverse elements contributing to H. pylori's colonization and infection. The interplay between virulence factors, phase variable genes, and host genetics determines the outcome of the infection. Despite biochemical insights into many factors, their comprehensive regulation remains an understudied area. By offering a panoramic view of these factors and their functions, this study enhances understanding of the bacterium's perspective, i.e. H. pylori's journey from infiltration to successful establishment within the host's stomach.
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Affiliation(s)
- Arghyadeep Bhattacharjee
- Department of Biotechnology, National Institute of Technology Durgapur, Durgapur, West Bengal, 713209, India
- Department of Microbiology, Kingston College of Science, Beruanpukuria, Barasat, West Bengal, 700219, India
| | - Om Saswat Sahoo
- Department of Biotechnology, National Institute of Technology Durgapur, Durgapur, West Bengal, 713209, India
| | - Ahana Sarkar
- Department of Biotechnology, National Institute of Technology Durgapur, Durgapur, West Bengal, 713209, India
| | - Saurabh Bhattacharya
- Department of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, The Hebrew University of Jerusalem, P.O.B. 12272, 9112001, Jerusalem, Israel
| | - Rukhsana Chowdhury
- School of Biological Sciences, RKM Vivekananda Educational and Research Institute Narendrapur, Kolkata, India
| | - Samarjit Kar
- Department of Mathematics, National Institute of Technology Durgapur, Durgapur, West Bengal, 713209, India
| | - Oindrilla Mukherjee
- Department of Biotechnology, National Institute of Technology Durgapur, Durgapur, West Bengal, 713209, India.
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Feng Z, Li H, Hao Y, Peng C, Ou L, Jia J, Xun M, Zou Y, Chen M, Zhang G, Yao M. In vitro anti- Helicobacter pylori activity and the underlining mechanism of an empirical herbal formula - Hezi Qingyou. Front Microbiol 2024; 15:1355460. [PMID: 38440143 PMCID: PMC10910045 DOI: 10.3389/fmicb.2024.1355460] [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: 12/14/2023] [Accepted: 02/05/2024] [Indexed: 03/06/2024] Open
Abstract
Background Helicobacter pylori (H. pylori) is thought to primarily colonize the human stomach and lead to various gastrointestinal disorders, such as gastritis and gastric cancer. Currently, main eradication treatment is triple or quadruple therapy centered on antibiotics. Due to antibiotic resistance, the eradication rate of H. pylori is decreasing gradually. Therefore, searching for anti-H. pylori drugs from herbal sources has become a strategy for the treatment. Our team proposed a Hezi Qingyou Formula (HZQYF), composed of Chebulae Fructus, Ficus hirta Vahl and Cloves, and studied its anti-H. pylori activity and mechanism. Methods Chemical components of HZQYF were studied using UHPLC-MS/MS and HPLC. Broth microdilution method and agar dilution method were used to evaluate HZQYF's antibacterial activity. The effects of HZQYF on expression of adhesion genes (alpA, alpB, babA), urease genes (ureE, ureF), and flagellar genes (flaA, flaB) were explored using Reverse Transcription-quantitative Polymerase Chain Reaction (RT-qPCR) technology. Effects on morphology and permeability of the extracellular membrane were studied using scanning electron microscopy (SEM) and N-phenylnaphthalen-1-amine (NPN) uptake. Effect on urease activity was studied using a urease kinetics analysis in vitro. Immunofluorescence staining method was used to examine the effect on adhesion. Western blot was used to examine the effect on cagA protein. Results Minimum inhibitory concentration (MIC) values of the formula against H. pylori clinical strains and standard strains were 80-160 μg/mL, and minimum bactericidal concentration (MBC) values were 160-320 μg/mL. The formula could down-regulate the expression of adhesion genes (alpA, alpB, babA), urease genes (ureE, ureF) and flagellar genes (flaA, flaB), change the morphology of H. pylori, increase its extracellular membrane permeability, and decrease its urease activity. Conclusion Present studies confirmed that HZQYF had promising in vitro anti-H. pylori activities and demonstrated its possible mechanism of action by down-regulating the bacterial adhesion, urease, and flagellar gene expression, which provided scientific bases for further clinical investigations.
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Affiliation(s)
- Zhong Feng
- School of Pharmaceutical Sciences, Sun Yat-sen University, Shenzhen, China
- State Key Laboratory of Integration and Innovation of Classic Formula and Modern Chinese Medicine, Lunan Pharmaceutical Group Co., Ltd., Linyi, China
- International Pharmaceutical Engineering Laboratory in Shandong Province, Shandong New Time Pharmaceutical Co., Ltd., Linyi, China
| | - Hui Li
- State Key Laboratory of Integration and Innovation of Classic Formula and Modern Chinese Medicine, Lunan Pharmaceutical Group Co., Ltd., Linyi, China
- International Pharmaceutical Engineering Laboratory in Shandong Province, Shandong New Time Pharmaceutical Co., Ltd., Linyi, China
| | - Yajie Hao
- State Key Laboratory of Integration and Innovation of Classic Formula and Modern Chinese Medicine, Lunan Pharmaceutical Group Co., Ltd., Linyi, China
- International Pharmaceutical Engineering Laboratory in Shandong Province, Shandong New Time Pharmaceutical Co., Ltd., Linyi, China
| | - Chang Peng
- School of Pharmaceutical Sciences, Sun Yat-sen University, Shenzhen, China
| | - Ling Ou
- School of Pharmaceutical Sciences, Sun Yat-sen University, Shenzhen, China
| | - Junwei Jia
- State Key Laboratory of Integration and Innovation of Classic Formula and Modern Chinese Medicine, Lunan Pharmaceutical Group Co., Ltd., Linyi, China
- International Pharmaceutical Engineering Laboratory in Shandong Province, Shandong New Time Pharmaceutical Co., Ltd., Linyi, China
| | - Mingjin Xun
- State Key Laboratory of Integration and Innovation of Classic Formula and Modern Chinese Medicine, Lunan Pharmaceutical Group Co., Ltd., Linyi, China
- International Pharmaceutical Engineering Laboratory in Shandong Province, Shandong New Time Pharmaceutical Co., Ltd., Linyi, China
| | - Yuanjing Zou
- School of Pharmaceutical Sciences, Sun Yat-sen University, Shenzhen, China
| | - Meiyun Chen
- School of Pharmaceutical Sciences, Sun Yat-sen University, Shenzhen, China
| | - Guimin Zhang
- State Key Laboratory of Integration and Innovation of Classic Formula and Modern Chinese Medicine, Lunan Pharmaceutical Group Co., Ltd., Linyi, China
- International Pharmaceutical Engineering Laboratory in Shandong Province, Shandong New Time Pharmaceutical Co., Ltd., Linyi, China
| | - Meicun Yao
- School of Pharmaceutical Sciences, Sun Yat-sen University, Shenzhen, China
- Nanchang Research Institute, Sun Yat-sen University, Jiangxi, China
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5
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Reyes VE. Helicobacter pylori and Its Role in Gastric Cancer. Microorganisms 2023; 11:1312. [PMID: 37317287 DOI: 10.3390/microorganisms11051312] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 05/08/2023] [Accepted: 05/15/2023] [Indexed: 06/16/2023] Open
Abstract
Gastric cancer is a challenging public health concern worldwide and remains a leading cause of cancer-related mortality. The primary risk factor implicated in gastric cancer development is infection with Helicobacter pylori. H. pylori induces chronic inflammation affecting the gastric epithelium, which can lead to DNA damage and the promotion of precancerous lesions. Disease manifestations associated with H. pylori are attributed to virulence factors with multiple activities, and its capacity to subvert host immunity. One of the most significant H. pylori virulence determinants is the cagPAI gene cluster, which encodes a type IV secretion system and the CagA toxin. This secretion system allows H. pylori to inject the CagA oncoprotein into host cells, causing multiple cellular perturbations. Despite the high prevalence of H. pylori infection, only a small percentage of affected individuals develop significant clinical outcomes, while most remain asymptomatic. Therefore, understanding how H. pylori triggers carcinogenesis and its immune evasion mechanisms is critical in preventing gastric cancer and mitigating the burden of this life-threatening disease. This review aims to provide an overview of our current understanding of H. pylori infection, its association with gastric cancer and other gastric diseases, and how it subverts the host immune system to establish persistent infection.
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Affiliation(s)
- Victor E Reyes
- Department of Pediatrics and Microbiology & Immunology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0372, USA
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6
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McClain MS, Bryant KN, McDonald WH, Algood HMS, Cover TL. Identification of an Essential LolD-Like Protein in Helicobacter pylori. J Bacteriol 2023; 205:e0005223. [PMID: 36971548 PMCID: PMC10127691 DOI: 10.1128/jb.00052-23] [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: 02/03/2023] [Accepted: 02/24/2023] [Indexed: 03/29/2023] Open
Abstract
The localization of lipoprotein (Lol) system is used by Gram-negative bacteria to export lipoproteins to the outer membrane. Lol proteins and models of how Lol transfers lipoproteins from the inner to the outer membrane have been extensively characterized in the model organism Escherichia coli, but in numerous bacterial species, lipoprotein synthesis and export pathways deviate from the E. coli paradigm. For example, in the human gastric bacterium Helicobacter pylori, a homolog of the E. coli outer membrane component LolB is not found, E. coli LolC and LolE correspond to a single inner membrane component (LolF), and a homolog of the E. coli cytoplasmic ATPase LolD has not been identified. In the present study, we sought to identify a LolD-like protein in H. pylori. We used affinity-purification mass spectrometry to identify interaction partners of the H. pylori ATP-binding cassette (ABC) family permease LolF and identified the ABC family ATP-binding protein HP0179 as its interaction partner. We engineered H. pylori to conditionally express HP0179 and showed that HP0179 and its conserved ATP binding and ATP hydrolysis motifs are essential for H. pylori growth. We then performed affinity purification-mass spectrometry using HP0179 as the bait and identified LolF as its interaction partner. These results indicate that H. pylori HP0179 is a LolD-like protein and provide a more complete understanding of lipoprotein localization processes in H. pylori, a bacterium in which the Lol system deviates from the E. coli paradigm. IMPORTANCE Lipoproteins are critical in Gram-negative-bacteria for cell surface assembly of LPS, insertion of outer membrane proteins, and sensing envelope stress. Lipoproteins also contribute to bacterial pathogenesis. For many of these functions, lipoproteins must localize to the Gram-negative outer membrane. Transporting lipoproteins to the outer membrane involves the Lol sorting pathway. Detailed analyses of the Lol pathway have been performed in the model organism Escherichia coli, but many bacteria utilize altered components or are missing essential components of the E. coli Lol pathway. Identifying a LolD-like protein in Helicobacter pylori is important to better understand the Lol pathway in diverse bacterial classes. This becomes particularly relevant as lipoprotein localization is targeted for antimicrobial development.
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Affiliation(s)
- Mark S. McClain
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection Immunology and Inflammation, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Kaeli N. Bryant
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - W. Hayes McDonald
- Proteomics Laboratory, Mass Spectrometry Research Center, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Holly M. Scott Algood
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection Immunology and Inflammation, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee, USA
| | - Timothy L. Cover
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection Immunology and Inflammation, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee, USA
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El-Kafrawy SA, Abbas AT, Oelkrug C, Tahoon M, Ezzat S, Zumla A, Azhar EI. IgY antibodies: The promising potential to overcome antibiotic resistance. Front Immunol 2023; 14:1065353. [PMID: 36742328 PMCID: PMC9896010 DOI: 10.3389/fimmu.2023.1065353] [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: 10/09/2022] [Accepted: 01/05/2023] [Indexed: 01/22/2023] Open
Abstract
Antibiotic resistant bacteria are a growing threat to global health security. Whilst the emergence of antimicrobial resistance (AMR) is a natural phenomenon, it is also driven by antibiotic exposure in health care, agriculture, and the environment. Antibiotic pressure and inappropriate use of antibiotics are important factors which drive resistance. Apart from their use to treat bacterial infections in humans, antibiotics also play an important role in animal husbandry. With limited antibiotic options, alternate strategies are required to overcome AMR. Passive immunization through oral, nasal and topical administration of egg yolk-derived IgY antibodies from immunized chickens were recently shown to be effective for treating bacterial infections in animals and humans. Immunization of chickens with specific antigens offers the possibility of creating specific antibodies targeting a wide range of antibiotic-resistant bacteria. In this review, we describe the growing global problem of antimicrobial resistance and highlight the promising potential of the use of egg yolk IgY antibodies for the treatment of bacterial infections, particularly those listed in the World Health Organization priority list.
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Affiliation(s)
- Sherif A El-Kafrawy
- Special Infectious Agents Unit-BSL3, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.,Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.,Department of Clinical Pathology, National Liver Institute, Menoufia University, Shebin El-Kom, Egypt
| | - Aymn T Abbas
- Special Infectious Agents Unit-BSL3, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.,Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.,Biotechnology Research Laboratories, Gastroenterology, Surgery Centre, Mansoura University, Mansoura, Egypt
| | | | - Marwa Tahoon
- Epidemiology and Preventive Medicine Department, National Liver Institute, Menoufia University, Shebin El-Kom, Egypt
| | - Sameera Ezzat
- Epidemiology and Preventive Medicine Department, National Liver Institute, Menoufia University, Shebin El-Kom, Egypt.,MARC for Medical Services and Scientific Research, 6th of October City, Giza, Egypt
| | - Alimuddin Zumla
- Special Infectious Agents Unit-BSL3, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.,Department of Infection, Division of Infection and Immunity, Centre for Clinical Microbiology, University College London, London, United Kingdom.,National Institute for Health and Care Research (NIHR) Biomedical Research Centre, University College London Hospitals, London, United Kingdom
| | - Esam I Azhar
- Special Infectious Agents Unit-BSL3, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.,Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
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Wizenty J, Sigal M. Gastric Stem Cell Biology and Helicobacter pylori Infection. Curr Top Microbiol Immunol 2023; 444:1-24. [PMID: 38231213 DOI: 10.1007/978-3-031-47331-9_1] [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] [Indexed: 01/18/2024]
Abstract
Helicobacter pylori colonizes the human gastric mucosa and persists lifelong. An interactive network between the bacteria and host cells shapes a unique microbial niche within gastric glands that alters epithelial behavior, leading to pathologies such as chronic gastritis and eventually gastric cancer. Gland colonization by the bacterium initiates aberrant trajectories by inducing long-term inflammatory and regenerative gland responses, which involve various specialized epithelial and stromal cells. Recent studies using cell lineage tracing, organoids and scRNA-seq techniques have significantly advanced our knowledge of the molecular "identity" of epithelial and stromal cell subtypes during normal homeostasis and upon infection, and revealed the principles that underly stem cell (niche) behavior under homeostatic conditions as well as upon H. pylori infection. The activation of long-lived stem cells deep in the gastric glands has emerged as a key prerequisite of H. pylori-associated gastric site-specific pathologies such as hyperplasia in the antrum, and atrophy or metaplasia in the corpus, that are considered premalignant lesions. In addition to altering the behaviour of bona fide stem cells, injury-driven de-differentiation and trans-differentation programs, such as "paligenosis", subsequently allow highly specialized secretory cells to re-acquire stem cell functions, driving gland regeneration. This plastic regenerative capacity of gastric glands is required to maintain homeostasis and repair mucosal injuries. However, these processes are co-opted in the context of stepwise malignant transformation in chronic H. pylori infection, causing the emergence, selection and expansion of cancer-promoting stem cells.
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Affiliation(s)
- Jonas Wizenty
- Division of Gastroenterology and Hepatology, Medical Department, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Michael Sigal
- Division of Gastroenterology and Hepatology, Medical Department, Charité-Universitätsmedizin Berlin, Berlin, Germany.
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Teng KW, Hsieh KS, Hung JS, Wang CJ, Liao EC, Chen PC, Lin YH, Wu DC, Lin CH, Wang WC, Chan HL, Huang SK, Kao MC. Helicobacter pylori employs a general protein glycosylation system for the modification of outer membrane adhesins. Gut Microbes 2022; 14:2130650. [PMID: 36206406 PMCID: PMC9553153 DOI: 10.1080/19490976.2022.2130650] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Helicobacter pylori infection is associated with the development of several gastric diseases including gastric cancer. To reach a long-term colonization in the host stomach, H. pylori employs multiple outer membrane adhesins for binding to the gastric mucosa. However, due to the redundancy of adhesins that complement the adhesive function of bacteria, targeting each individual adhesin alone usually achieves nonideal outcomes for preventing bacterial adhesion. Here, we report that key adhesins AlpA/B and BabA/B in H. pylori are modified by glycans and display a two-step molecular weight upshift pattern from the cytoplasm to the inner membrane and from the inner membrane to the outer membrane. Nevertheless, this upshift pattern is missing when the expression of some enzymes related to lipopolysaccharide (LPS) biosynthesis, including the LPS O-antigen assembly and ligation enzymes WecA, Wzk, and WaaL, is disrupted, indicating that the underlying mechanisms and the involved enzymes for the adhesin glycosylation are partially shared with the LPS biosynthesis. Loss of the adhesin glycosylation not only reduces the protease resistance and the stability of the tested adhesins but also changes the adhesin-binding ability. In addition, mutations in the LPS biosynthesis cause a significant reduction in bacterial adhesion in the in vitro cell-line model. The current findings reveal that H. pylori employs a general protein glycosylation system related to LPS biosynthesis for adhesin modification and its biological significance. The enzymes required for adhesin glycosylation rather than the adhesins themselves are potentially better drug targets for preventing or treating H. pylori infection.
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Affiliation(s)
- Kai-Wen Teng
- Institute of Molecular Medicine, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Kai-Siang Hsieh
- Institute of Molecular Medicine, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Ji-Shiuan Hung
- Institute of Molecular Medicine, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Chun-Jen Wang
- Institute of Molecular Medicine, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - En-Chi Liao
- Institute of Bioinformatics and Structural Biology, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan,Department of Medical Science, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Pei-Chun Chen
- Institute of Molecular Medicine, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Ying-Hsuan Lin
- Institute of Molecular Medicine, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Deng-Chyang Wu
- Division of Gastroenterology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chun-Hung Lin
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Wen-Ching Wang
- Institute of Molecular and Cellular Biology, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan,Department of Life Science, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Hong-Lin Chan
- Institute of Bioinformatics and Structural Biology, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan,Department of Medical Science, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Shau-Ku Huang
- National Institute of Environmental Health Sciences, National Health Research Institutes, Zhunan, Taiwan
| | - Mou-Chieh Kao
- Institute of Molecular Medicine, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan,Department of Life Science, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan,CONTACT Mou-Chieh Kao Institute of Molecular Medicine, College of Life Science, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu 300044, Taiwan
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10
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Clarke KR, Hor L, Pilapitiya A, Luirink J, Paxman JJ, Heras B. Phylogenetic Classification and Functional Review of Autotransporters. Front Immunol 2022; 13:921272. [PMID: 35860281 PMCID: PMC9289746 DOI: 10.3389/fimmu.2022.921272] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 06/06/2022] [Indexed: 11/30/2022] Open
Abstract
Autotransporters are the core component of a molecular nano-machine that delivers cargo proteins across the outer membrane of Gram-negative bacteria. Part of the type V secretion system, this large family of proteins play a central role in controlling bacterial interactions with their environment by promoting adhesion to surfaces, biofilm formation, host colonization and invasion as well as cytotoxicity and immunomodulation. As such, autotransporters are key facilitators of fitness and pathogenesis and enable co-operation or competition with other bacteria. Recent years have witnessed a dramatic increase in the number of autotransporter sequences reported and a steady rise in functional studies, which further link these proteins to multiple virulence phenotypes. In this review we provide an overview of our current knowledge on classical autotransporter proteins, the archetype of this protein superfamily. We also carry out a phylogenetic analysis of their functional domains and present a new classification system for this exquisitely diverse group of bacterial proteins. The sixteen phylogenetic divisions identified establish sensible relationships between well characterized autotransporters and inform structural and functional predictions of uncharacterized proteins, which may guide future research aimed at addressing multiple unanswered aspects in this group of therapeutically important bacterial factors.
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Affiliation(s)
- Kaitlin R. Clarke
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia
| | - Lilian Hor
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia
| | - Akila Pilapitiya
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia
| | - Joen Luirink
- Department of Molecular Microbiology, Amsterdam Institute of Molecular and Life Sciences (AIMMS), Vrije Universiteit, Amsterdam, Netherlands
| | - Jason J. Paxman
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia
- *Correspondence: Begoña Heras, ; Jason J. Paxman,
| | - Begoña Heras
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC, Australia
- *Correspondence: Begoña Heras, ; Jason J. Paxman,
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11
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Nguyen H, Herrmann F, König S, Goycoolea F, Hensel A. Structural characterization of the carbohydrate and protein part of arabinogalactan protein from Basella alba stem and antiadhesive activity of polysaccharides from B. alba against Helicobacter pylori. Fitoterapia 2022; 157:105132. [DOI: 10.1016/j.fitote.2022.105132] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 01/17/2022] [Accepted: 01/17/2022] [Indexed: 01/17/2023]
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12
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Zhang L, Xiao Y, Ji L, Lin M, Zou Y, Zhao J, Zhao S. Potential Therapeutic Effects of Egg Yolk Antibody (IgY) in Helicobacter pylori Infections─A Review. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:13691-13699. [PMID: 34783242 DOI: 10.1021/acs.jafc.1c05398] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Currently, the infection with Helicobacter pylori affects about half of the world's population, and the most common therapy to treat H. pylori is the first line clarithromycin-based triple therapy or the quadruple therapy. However, drug resistance, eradication in a low level, high rate of reinfection, and gastrointestinal side effects among the causative organisms for H. pylori infection pose a critical challenge to the global health care community. Therefore, new approaches to treat H. pylori infections are urgently needed. Chicken egg yolk constituting a source of immunoglobulin Y (IgY) has attracted noticeable attention for its advantages of cost-effective extraction, minimization of animal harm and suffering, and induction of no specific resistance and is, therefore, being regarded as an alternative therapy for H. pylori infection. This review is intended to summarize various H. pylori antigens for IgY preparation in terms of their application, mechanism, and limitations.
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Affiliation(s)
- Leheng Zhang
- Department of Pharmaceutical Engineering, School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, Guangdong 510006, People's Republic of China
| | - Yire Xiao
- Department of Pharmaceutical Engineering, School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, Guangdong 510006, People's Republic of China
| | - Li Ji
- Department of Pharmaceutical Engineering, School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, Guangdong 510006, People's Republic of China
| | - Mingxia Lin
- Department of Pharmaceutical Engineering, School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, Guangdong 510006, People's Republic of China
| | - Yikui Zou
- Department of Pharmaceutical Engineering, School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, Guangdong 510006, People's Republic of China
| | - Jingjing Zhao
- Department of Pharmaceutical Engineering, School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, Guangdong 510006, People's Republic of China
| | - Suqing Zhao
- Department of Pharmaceutical Engineering, School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, Guangdong 510006, People's Republic of China
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13
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Abstract
Helicobacter pylori genomes encode over 60 predicted outer membrane proteins (OMPs). Several OMPs in the Hop family act as adhesins, but the functions of most Hop proteins are unknown. To identify hop mutant strains exhibiting differential fitness in vivo compared to in vitro, we used a genetic barcoding method that allowed us to track changes in the proportional abundance of H. pylori strains within a mixed population. We generated a library of hop mutant strains, each containing a unique nucleotide barcode, as well as a library of control strains, each containing a nucleotide barcode in an intergenic region predicted to be a neutral locus unrelated to bacterial fitness. We orogastrically inoculated each of the libraries into mice and analyzed compositional changes in the populations over time in vivo compared to changes detected in the populations during library passage in vitro. The control library proliferated as a relatively stable community in vitro, but there was a reduction in the population diversity of this library in vivo and marked variation in the dominant strains recovered from individual animals, consistent with the existence of a nonselective bottleneck in vivo. We did not identify any OMP mutants exhibiting fitness defects exclusively in vivo without corresponding fitness defects in vitro. Conversely, a babA mutant exhibited a strong fitness advantage in vivo but not in vitro. These findings, when taken together with results of other studies, suggest that production of BabA may have differential effects on H. pylori fitness depending on the environmental conditions.
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14
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Matos R, Amorim I, Magalhães A, Haesebrouck F, Gärtner F, Reis CA. Adhesion of Helicobacter Species to the Human Gastric Mucosa: A Deep Look Into Glycans Role. Front Mol Biosci 2021; 8:656439. [PMID: 34026832 PMCID: PMC8138122 DOI: 10.3389/fmolb.2021.656439] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 04/22/2021] [Indexed: 12/15/2022] Open
Abstract
Helicobacter species infections may be associated with the development of gastric disorders, such as gastritis, peptic ulcers, intestinal metaplasia, dysplasia and gastric carcinoma. Binding of these bacteria to the gastric mucosa occurs through the recognition of specific glycan receptors expressed by the host epithelial cells. This review addresses the state of the art knowledge on these host glycan structures and the bacterial adhesins involved in Helicobacter spp. adhesion to gastric mucosa colonization. Glycans are expressed on every cell surface and they are crucial for several biological processes, including protein folding, cell signaling and recognition, and host-pathogen interactions. Helicobacter pylori is the most predominant gastric Helicobacter species in humans. The adhesion of this bacterium to glycan epitopes present on the gastric epithelial surface is a crucial step for a successful colonization. Major adhesins essential for colonization and infection are the blood-group antigen-binding adhesin (BabA) which mediates the interaction with fucosylated H-type 1 and Lewis B glycans, and the sialic acid-binding adhesin (SabA) which recognizes the sialyl-Lewis A and X glycan antigens. Since not every H. pylori strain expresses functional BabA or SabA adhesins, other bacterial proteins are most probably also involved in this adhesion process, including LabA (LacdiNAc-binding adhesin), which binds to the LacdiNAc motif on MUC5AC mucin. Besides H. pylori, several other gastric non-Helicobacter pylori Helicobacters (NHPH), mainly associated with pigs (H. suis) and pets (H. felis, H. bizzozeronii, H. salomonis, and H. heilmannii), may also colonize the human stomach and cause gastric disease, including gastritis, peptic ulcers and mucosa-associated lymphoid tissue (MALT) lymphoma. These NHPH lack homologous to the major known adhesins involved in colonization of the human stomach. In humans, NHPH infection rate is much lower than in the natural hosts. Differences in the glycosylation profile between gastric human and animal mucins acting as glycan receptors for NHPH-associated adhesins, may be involved. The identification and characterization of the key molecules involved in the adhesion of gastric Helicobacter species to the gastric mucosa is important to understand the colonization and infection strategies displayed by different members of this genus.
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Affiliation(s)
- Rita Matos
- Instituto de Investigação e Inovação Em Saúde (i3S), Universidade do Porto, Porto, Portugal
- Instituto de Patologia e Imunologia Molecular da Universidade do Porto (IPATIMUP), Porto, Portugal
- Instituto de Ciências Biomédicas Abel Salazar da Universidade do Porto (ICBAS), Porto, Portugal
| | - Irina Amorim
- Instituto de Investigação e Inovação Em Saúde (i3S), Universidade do Porto, Porto, Portugal
- Instituto de Patologia e Imunologia Molecular da Universidade do Porto (IPATIMUP), Porto, Portugal
- Instituto de Ciências Biomédicas Abel Salazar da Universidade do Porto (ICBAS), Porto, Portugal
| | - Ana Magalhães
- Instituto de Investigação e Inovação Em Saúde (i3S), Universidade do Porto, Porto, Portugal
- Instituto de Patologia e Imunologia Molecular da Universidade do Porto (IPATIMUP), Porto, Portugal
| | - Freddy Haesebrouck
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
| | - Fátima Gärtner
- Instituto de Investigação e Inovação Em Saúde (i3S), Universidade do Porto, Porto, Portugal
- Instituto de Patologia e Imunologia Molecular da Universidade do Porto (IPATIMUP), Porto, Portugal
| | - Celso A. Reis
- Instituto de Investigação e Inovação Em Saúde (i3S), Universidade do Porto, Porto, Portugal
- Instituto de Patologia e Imunologia Molecular da Universidade do Porto (IPATIMUP), Porto, Portugal
- Instituto de Ciências Biomédicas Abel Salazar da Universidade do Porto (ICBAS), Porto, Portugal
- Faculdade de Medicina da Universidade do Porto (FMUP), Porto, Portugal
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15
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Xu X, Chen J, Huang X, Feng S, Zhang X, She F, Wen Y. The Role of a Dipeptide Transporter in the Virulence of Human Pathogen, Helicobacter pylori. Front Microbiol 2021; 12:633166. [PMID: 33732225 PMCID: PMC7959749 DOI: 10.3389/fmicb.2021.633166] [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: 11/24/2020] [Accepted: 02/05/2021] [Indexed: 12/16/2022] Open
Abstract
Helicobacter pylori harbors a dipeptide (Dpp) transporter consisting of a substrate-binding protein (DppA), two permeases (DppB and C), and two ATPases (DppD and F). The Dpp transporter is responsible for the transportation of dipeptides and short peptides. We found that its expression is important for the growth of H. pylori. To understand the role of the Dpp transporter in the pathogenesis of H. pylori, the expression of virulence factors and H. pylori-induced IL-8 production were investigated in H. pylori wild-type and isogenic H. pylori Dpp transporter mutants. We found that expression of CagA was downregulated, while expression of type 4 secretion system (T4SS) components was upregulated in Dpp transporter mutants. The DppA mutant strain expressed higher levels of outer membrane proteins (OMPs), including BabA, HopZ, OipA, and SabA, and showed a higher adhesion level to gastric epithelial AGS cells compared with the H. pylori 26695 wild-type strain. After infection of AGS cells, H. pylori ΔdppA induced a higher level of NF-κB activation and IL-8 production compared with wild-type. These results suggested that in addition to supporting the growth of H. pylori, the Dpp transporter causes bacteria to alter the expression of virulence factors and reduces H. pylori-induced NF-κB activation and IL-8 production in gastric epithelial cells.
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Affiliation(s)
- Xiaohong Xu
- Key Laboratory of Gastrointestinal Cancer (Fujian Medical University), Ministry of Education, Fuzhou, China.,Fujian Key Laboratory of Tumor Microbiology, Department of Medical Microbiology, Fujian Medical University, Fuzhou, China.,Fujian Medical University Union Hospital, Fuzhou, China
| | - Junwei Chen
- Key Laboratory of Gastrointestinal Cancer (Fujian Medical University), Ministry of Education, Fuzhou, China.,Fujian Key Laboratory of Tumor Microbiology, Department of Medical Microbiology, Fujian Medical University, Fuzhou, China
| | - Xiaoxing Huang
- Key Laboratory of Gastrointestinal Cancer (Fujian Medical University), Ministry of Education, Fuzhou, China.,Fujian Key Laboratory of Tumor Microbiology, Department of Medical Microbiology, Fujian Medical University, Fuzhou, China
| | - Shunhang Feng
- Key Laboratory of Gastrointestinal Cancer (Fujian Medical University), Ministry of Education, Fuzhou, China.,Fujian Key Laboratory of Tumor Microbiology, Department of Medical Microbiology, Fujian Medical University, Fuzhou, China
| | - Xiaoyan Zhang
- Key Laboratory of Gastrointestinal Cancer (Fujian Medical University), Ministry of Education, Fuzhou, China.,Fujian Key Laboratory of Tumor Microbiology, Department of Medical Microbiology, Fujian Medical University, Fuzhou, China
| | - Feifei She
- Key Laboratory of Gastrointestinal Cancer (Fujian Medical University), Ministry of Education, Fuzhou, China.,Fujian Key Laboratory of Tumor Microbiology, Department of Medical Microbiology, Fujian Medical University, Fuzhou, China
| | - Yancheng Wen
- Key Laboratory of Gastrointestinal Cancer (Fujian Medical University), Ministry of Education, Fuzhou, China.,Fujian Key Laboratory of Tumor Microbiology, Department of Medical Microbiology, Fujian Medical University, Fuzhou, China
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16
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Banga Ndzouboukou JL, Lei Q, Ullah N, Zhang Y, Hao L, Fan X. Helicobacter pylori adhesins: HpaA a potential antigen in experimental vaccines for H. pylori. Helicobacter 2021; 26:e12758. [PMID: 33259676 DOI: 10.1111/hel.12758] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 08/14/2020] [Accepted: 09/01/2020] [Indexed: 12/19/2022]
Abstract
BACKGROUND Helicobacter pylori is a gram-negative bacterium involved in many gastric pathologies such as ulcers and cancers. Although the treatment for this infection has existed for several years, the development of a vaccine is nevertheless necessary to reduce the severe forms of the disease. For more than three decades, many advances have been made particularly in the understanding of virulence factors as well as the pathogenesis of gastric diseases caused by H. pylori. Among these key virulence factors, specific antigens have been identified: Urease, Vacuolating cytotoxin A (VacA), Cytotoxin-associated gene A (CagA), Blood group antigen-binding adhesin (BabA), H. pylori adhesin A (HpaA), and others. OBJECTIVES This review will focus on H. pylori adhesins, in particular, on HpaA and on the current knowledge of H. pylori vaccines. METHODS All of the information included in this review was retrieved from published studies on H. pylori adhesins in H. pylori infections. RESULTS These proteins, used in their native or recombinant forms, induce protection against H. pylori in experimental animal models. CONCLUSION H. pylori adhesins are known to be promising candidate vaccines against H. pylori. Future research should be carried out on adhesins, in particular, on HpaA.
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Affiliation(s)
- Jo-Lewis Banga Ndzouboukou
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Qing Lei
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Nadeem Ullah
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yandi Zhang
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ling Hao
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xionglin Fan
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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17
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Baj J, Forma A, Sitarz M, Portincasa P, Garruti G, Krasowska D, Maciejewski R. Helicobacter pylori Virulence Factors-Mechanisms of Bacterial Pathogenicity in the Gastric Microenvironment. Cells 2020; 10:E27. [PMID: 33375694 PMCID: PMC7824444 DOI: 10.3390/cells10010027] [Citation(s) in RCA: 134] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 12/18/2020] [Accepted: 12/22/2020] [Indexed: 12/11/2022] Open
Abstract
Gastric cancer constitutes one of the most prevalent malignancies in both sexes; it is currently the fourth major cause of cancer-related deaths worldwide. The pathogenesis of gastric cancer is associated with the interaction between genetic and environmental factors, among which infection by Helicobacter pylori (H. pylori) is of major importance. The invasion, survival, colonization, and stimulation of further inflammation within the gastric mucosa are possible due to several evasive mechanisms induced by the virulence factors that are expressed by the bacterium. The knowledge concerning the mechanisms of H. pylori pathogenicity is crucial to ameliorate eradication strategies preventing the possible induction of carcinogenesis. This review highlights the current state of knowledge and the most recent findings regarding H. pylori virulence factors and their relationship with gastric premalignant lesions and further carcinogenesis.
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Affiliation(s)
- Jacek Baj
- Department of Anatomy, Medical University of Lublin, 20-400 Lublin, Poland;
| | - Alicja Forma
- Chair and Department of Forensic Medicine, Medical University of Lublin, 20-090 Lublin, Poland;
| | - Monika Sitarz
- Department of Conservative Dentistry with Endodontics, Medical University of Lublin, 20-090 Lublin, Poland;
| | - Piero Portincasa
- Clinica Medica “Augusto Murri”, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro”, 70124 Bari, Italy;
| | - Gabriella Garruti
- Section of Endocrinology, Department of Emergency and Organ Transplantations, University of Bari “Aldo Moro” Medical School, Piazza G. Cesare 11, 70124 Bari, Italy;
| | - Danuta Krasowska
- Department of Dermatology, Venerology and Paediatric Dermatology of Medical University of Lublin, 20-081 Lublin, Poland;
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18
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Paraskevopoulou V, Schimpl M, Overman RC, Stolnik S, Chen Y, Nguyen L, Winkler GS, Gellert P, Klassen JS, Falcone FH. Structural and binding characterization of the LacdiNAc-specific adhesin (LabA; HopD) exodomain from Helicobacter pylori. Curr Res Struct Biol 2020; 3:19-29. [PMID: 34235483 PMCID: PMC8244420 DOI: 10.1016/j.crstbi.2020.12.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 10/31/2020] [Accepted: 12/10/2020] [Indexed: 01/02/2023] Open
Abstract
Helicobacter pylori (H. pylori) uses several outer membrane proteins for adhering to its host's gastric mucosa, an important step in establishing and preserving colonization. Several adhesins (SabA, BabA, HopQ) have been characterized in terms of their three-dimensional structure. A recent addition to the growing list of outer membrane porins is LabA (LacdiNAc-binding adhesin), which is thought to bind specifically to GalNAcβ1-4GlcNAc, occurring in the gastric mucosa. LabA47-496 protein expressed as His-tagged protein in the periplasm of E. coli and purified via subtractive IMAC after TEV cleavage and subsequent size exclusion chromatography, resulted in bipyramidal crystals with good diffraction properties. Here, we describe the 2.06 Å resolution structure of the exodomain of LabA from H. pylori strain J99 (PDB ID: 6GMM). Strikingly, despite the relatively low levels of sequence identity with the other three structurally characterized adhesins (20-49%), LabA shares an L-shaped fold with SabA and BabA. The 'head' region contains a 4 + 3 α-helix bundle, with a small insertion domain consisting of a short antiparallel beta sheet and an unstructured region, not resolved in the crystal structure. Sequence alignment of LabA from different strains shows a high level of conservation in the N- and C-termini, and identifies two main types based on the length of the insertion domain ('crown' region), the 'J99-type' (insertion ~31 amino acids), and the H. pylori '26695 type' (insertion ~46 amino acids). Analysis of ligand binding using Native Electrospray Ionization Mass Spectrometry (ESI-MS) together with solid phase-bound, ELISA-type assays could not confirm the originally described binding of GalNAcβ1-4GlcNAc-containing oligosaccharides, in line with other recent reports, which also failed to confirm LacdiNAc binding.
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Affiliation(s)
| | - Marianne Schimpl
- Structure, Biophysics and Fragment-based Lead Generation, Discovery Sciences, R&D, AstraZeneca, Cambridge, United Kingdom
| | - Ross C. Overman
- Protein Science, Discovery Sciences, R&D, AstraZeneca, Alderley Park, United Kingdom
| | - Snow Stolnik
- School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD, United Kingdom
| | - Yajie Chen
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, T6G 2G2, Canada
| | - Linh Nguyen
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, T6G 2G2, Canada
| | | | - Paul Gellert
- Innovation Strategy & External Liaison, Pharmaceutical Technology & Development, Operations, AstraZeneca, Macclesfield, United Kingdom
| | - John S. Klassen
- Alberta Glycomics Centre and Department of Chemistry, University of Alberta, Edmonton, T6G 2G2, Canada
| | - Franco H. Falcone
- School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD, United Kingdom
- Institute for Parasitology, Justus-Liebig-University Gießen, Schubertstr. 81, D-35392, Gießen, Germany
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19
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McClain MS, Voss BJ, Cover TL. Lipoprotein Processing and Sorting in Helicobacter pylori. mBio 2020; 11:e00911-20. [PMID: 32430470 PMCID: PMC7240156 DOI: 10.1128/mbio.00911-20] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 04/20/2020] [Indexed: 12/14/2022] Open
Abstract
Our current understanding of lipoprotein synthesis and localization in Gram-negative bacteria is based primarily on studies of Escherichia coli Newly synthesized E. coli prolipoproteins undergo posttranslational modifications catalyzed by three essential enzymes (Lgt, LspA, and Lnt). The mature lipoproteins are then sorted to the inner or outer membrane via the Lol system (LolABCDE). Recent studies suggested that this paradigm may not be universally applicable among different classes of proteobacteria. In this study, we conducted a systematic analysis of lipoprotein processing and sorting in Helicobacter pylori, a member of the Epsilonproteobacteria that colonizes the human stomach. We show that H. pylorilgt, lspA, and lnt homologs can complement conditionally lethal E. coli mutant strains in which expression of these genes is conditionally regulated. Mutagenesis studies and analyses of conditionally lethal H. pylori mutant strains indicate that lgt and lspA are essential for H. pylori growth but lnt is dispensable. H. pylorilolA and the single lolC (or lolE) homolog are also essential genes. We then explored the role of lipoproteins in H. pylori Cag type IV secretion system (Cag T4SS) activity. Comparative analysis of the putative VirB7 homolog CagT in wild-type and lnt mutant H. pylori strains indicates that CagT undergoes amino-terminal modifications consistent with lipidation, and we show that CagT lipidation is essential for CagT stability and Cag T4SS function. This work demonstrates that lipoprotein synthesis and localization in H. pylori diverge from the canonical pathways and that lipidation of a T4SS component is necessary for H. pylori Cag T4SS activity.IMPORTANCE Bacterial lipoproteins have diverse roles in multiple aspects of bacterial physiology, antimicrobial resistance, and pathogenesis. Dedicated pathways direct the posttranslational lipidation and localization of lipoproteins, but there is considerable variation in these pathways among the proteobacteria. In this study, we characterized the proteins responsible for lipoprotein synthesis and localization in Helicobacter pylori, a member of the Epsilonproteobacteria that contributes to stomach cancer pathogenesis. We also provide evidence suggesting that lipidation of CagT, a component of the H. pylori Cag T4SS, is required for delivery of the H. pylori CagA oncoprotein into human gastric cells. Overall, these results constitute the first systematic analysis of H. pylori lipoprotein production and localization pathways and reveal how these processes in H. pylori differ from corresponding pathways in model proteobacteria.
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Affiliation(s)
- Mark S McClain
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Bradley J Voss
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Timothy L Cover
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee, USA
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20
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Wizenty J, Tacke F, Sigal M. Responses of gastric epithelial stem cells and their niche to Helicobacter pylori infection. ANNALS OF TRANSLATIONAL MEDICINE 2020; 8:568. [PMID: 32775369 PMCID: PMC7347775 DOI: 10.21037/atm.2020.02.178] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Helicobacter pylori (H. pylori) are gram-negative bacteria that are able to colonize and persist in the stomach. Gastric cancer is tightly linked to chronic infection with this bacterium. Research over the last decades has illuminated the molecular interactions between H. pylori and host cells. It is now well established that H. pylori have multiple sophisticated means to adhere to epithelial cells and to manipulate their behavior. This interaction with the epithelium can lead to altered cell signaling, DNA damage and aberrant epithelial immunity. H. pylori are known to colonize the mucus layer of the stomach and surface epithelial cells. In addition, it has recently become clear that they can also penetrate the glands and directly interact with specialized epithelial cells deep in the glands. Understanding the biogeography of infection is important because gastric epithelial glands are composed of various types of short-lived differentiated cells that are constantly regenerated by a limited pool of long-lived stem cells located in base of gastric glands. Recent advances in gastric stem cell research not only led to identification of stem cell populations using specific markers but has also uncovered specific regulatory pathways and principles that govern gastric stem cell behavior and regeneration. Particularly, the stem cell state is largely dependent on signals from the niche cells that surround the stem cell compartment. The subpopulation of H. pylori that colonizes in the stem cell compartment triggers specific inflammatory responses and drives epithelial pathology. Colonization of gastric glands induces responses of the stem cell niche, simultaneously enhancing the cell turnover kinetics and driving the formation of antimicrobial cells in the gland base. These data reveal the high plasticity of the epithelium and its ability to adapt to the environment, which is necessary to regenerate and counterbalance infection, but simultaneously lays the grounds for development of gastric pathology and carcinogenesis.
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Affiliation(s)
- Jonas Wizenty
- Department of Hepatology & Gastroenterology, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, Germany
| | - Frank Tacke
- Department of Hepatology & Gastroenterology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Michael Sigal
- Department of Hepatology & Gastroenterology, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, Germany
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21
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Javed S, Skoog EC, Solnick JV. Impact of Helicobacter pylori Virulence Factors on the Host Immune Response and Gastric Pathology. Curr Top Microbiol Immunol 2019; 421:21-52. [PMID: 31123884 DOI: 10.1007/978-3-030-15138-6_2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Helicobacter pylori chronically infects nearly half the world's population, yet most of those infected remain asymptomatic throughout their lifetime. The outcome of infection-peptic ulcer disease or gastric cancer versus asymptomatic colonization-is a product of host genetics, environmental influences, and differences in bacterial virulence factors. Here, we review the current understanding of the cag pathogenicity island (cagPAI), the vacuolating cytotoxin (VacA), and a large family of outer membrane proteins (OMPs), which are among the best understood H. pylori virulence determinants that contribute to disease. Each of these virulence factors is characterized by allelic and phenotypic diversity that is apparent within and across individuals, as well as over time, and modulates inflammation. From the bacterial perspective, inflammation is probably a necessary evil because it promotes nutrient acquisition, but at the cost of reduction in bacterial load and therefore decreases the chance of transmission to a new host. The general picture that emerges is one of a chronic bacterial infection that is dependent on both inducing and carefully regulating the host inflammatory response. A better understanding of these regulatory mechanisms may have implications for the control of chronic inflammatory diseases that are increasingly common causes of human morbidity and mortality.
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Affiliation(s)
- Sundus Javed
- Department of Medicine, Department of Microbiology & Immunology, Center for Comparative Medicine, University of California, Davis School of Medicine, Davis, CA, 95616, USA.,Department of Biosciences, COMSATS Institute of Information Technology, Islamabad, Pakistan
| | - Emma C Skoog
- Department of Medicine, Department of Microbiology & Immunology, Center for Comparative Medicine, University of California, Davis School of Medicine, Davis, CA, 95616, USA
| | - Jay V Solnick
- Department of Medicine, Department of Microbiology & Immunology, Center for Comparative Medicine, University of California, Davis School of Medicine, Davis, CA, 95616, USA. .,Center for Comparative Medicine, University of California, Davis, Davis, CA, 95616, USA.
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22
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Carbohydrate-Dependent and Antimicrobial Peptide Defence Mechanisms Against Helicobacter pylori Infections. Curr Top Microbiol Immunol 2019; 421:179-207. [PMID: 31123890 DOI: 10.1007/978-3-030-15138-6_8] [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] [Indexed: 12/13/2022]
Abstract
The human stomach is a harsh and fluctuating environment for bacteria with hazards such as gastric acid and flow through of gastric contents into the intestine. H. pylori gains admission to a stable niche with nutrient access from exudates when attached to the epithelial cells under the mucus layer, whereof adherence to glycolipids and other factors provides stable and intimate attachment. To reach this niche, H. pylori must overcome mucosal defence mechanisms including the continuously secreted mucus layer, which provides several layers of defence: (1) mucins in the mucus layer can bind H. pylori and transport it away from the gastric niche with the gastric emptying, (2) mucins can inhibit H. pylori growth, both via glycans that can have antibiotic like function and via an aggregation-dependent mechanism, (3) antimicrobial peptides (AMPs) have antimicrobial activity and are retained in a strategic position in the mucus layer and (4) underneath the mucus layer, the membrane-bound mucins provide a second barrier, and can function as releasable decoys. Many of these functions are dependent on H. pylori interactions with host glycan structures, and both the host glycosylation and concentration of antimicrobial peptides change with infection and inflammation, making these interactions dynamic. Here, we review our current understanding of mucin glycan and antimicrobial peptide-dependent host defence mechanisms against H. pylori infection.
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23
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Benktander J, Barone A, Johansson MM, Teneberg S. Helicobacter pylori SabA binding gangliosides of human stomach. Virulence 2018; 9:738-751. [PMID: 29473478 PMCID: PMC5955481 DOI: 10.1080/21505594.2018.1440171] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 01/17/2018] [Accepted: 02/05/2018] [Indexed: 12/11/2022] Open
Abstract
Adhesion of Helicobacter pylori to the gastric mucosa is a prerequisite for the pathogenesis of H. pylori related diseases. In this study, we investigated the ganglioside composition of human stomach as the target for attachment mediated by H. pylori SabA (sialic acid binding adhesin). Acid glycosphingolipids were isolated from human stomach and separated into subfractions, which were characterized by mass spectrometry and by binding of antibodies, bacteria, and Solanum tuberosum lectin. H. pylori SabA binding gangliosides were characterized as Neu5Acα3-neolactohexaosylceramide and Neu5Acα3-neolactooctaosylceramide, while the other acid human stomach glycosphingolipids characterized (sulfatide and the gangliosides GM3, GD3, GM1, Neu5Acα3-neolactotetraosylceramide, GD1a and GD1b) were not recognized by the bacteria. Defining H. pylori binding glycosphingolipids of the human gastric mucosa will be useful to specifically target this microbe-host interaction for therapeutic intervention.
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Affiliation(s)
- John Benktander
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
| | - Angela Barone
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
| | - Miralda Madar Johansson
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
| | - Susann Teneberg
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
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24
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In silico proteomic and phylogenetic analysis of the outer membrane protein repertoire of gastric Helicobacter species. Sci Rep 2018; 8:15453. [PMID: 30337679 PMCID: PMC6194013 DOI: 10.1038/s41598-018-32476-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 09/03/2018] [Indexed: 12/16/2022] Open
Abstract
Helicobacter (H.) pylori is an important risk factor for gastric malignancies worldwide. Its outer membrane proteome takes an important role in colonization of the human gastric mucosa. However, in zoonotic non-H. pylori helicobacters (NHPHs) also associated with human gastric disease, the composition of the outer membrane (OM) proteome and its relative contribution to disease remain largely unknown. By means of a comprehensive survey of the diversity and distribution of predicted outer membrane proteins (OMPs) identified in all known gastric Helicobacter species with fully annotated genome sequences, we found genus- and species-specific families known or thought to be implicated in virulence. Hop adhesins, part of the Helicobacter-specific family 13 (Hop, Hor and Hom) were restricted to the gastric species H. pylori, H. cetorum and H. acinonychis. Hof proteins (family 33) were putative adhesins with predicted Occ- or MOMP-family like 18-stranded β-barrels. They were found to be widespread amongst all gastric Helicobacter species only sporadically detected in enterohepatic Helicobacter species. These latter are other members within the genus Helicobacter, although ecologically and genetically distinct. LpxR, a lipopolysaccharide remodeling factor, was also detected in all gastric Helicobacter species but lacking as well from the enterohepatic species H. cinaedi, H. equorum and H. hepaticus. In conclusion, our systemic survey of Helicobacter OMPs points to species and infection-site specific members that are interesting candidates for future virulence and colonization studies.
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25
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Coppens F, Castaldo G, Debraekeleer A, Subedi S, Moonens K, Lo A, Remaut H. Hop‐familyHelicobacterouter membrane adhesins form a novel class of Type 5‐like secretion proteins with an interrupted β‐barrel domain. Mol Microbiol 2018; 110:33-46. [DOI: 10.1111/mmi.14075] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/12/2018] [Indexed: 01/10/2023]
Affiliation(s)
- Fanny Coppens
- Structural and Molecular Microbiology VIB‐VUB Center for Structural Biology, VIB Brussels Belgium
- Structural Biology Brussels Vrije Universiteit Brussel Brussels Belgium
| | - Gaetano Castaldo
- Structural and Molecular Microbiology VIB‐VUB Center for Structural Biology, VIB Brussels Belgium
- Structural Biology Brussels Vrije Universiteit Brussel Brussels Belgium
| | - Ayla Debraekeleer
- Structural and Molecular Microbiology VIB‐VUB Center for Structural Biology, VIB Brussels Belgium
- Structural Biology Brussels Vrije Universiteit Brussel Brussels Belgium
| | - Suresh Subedi
- Structural and Molecular Microbiology VIB‐VUB Center for Structural Biology, VIB Brussels Belgium
- Structural Biology Brussels Vrije Universiteit Brussel Brussels Belgium
| | - Kristof Moonens
- Structural and Molecular Microbiology VIB‐VUB Center for Structural Biology, VIB Brussels Belgium
- Structural Biology Brussels Vrije Universiteit Brussel Brussels Belgium
| | - Alvin Lo
- Structural and Molecular Microbiology VIB‐VUB Center for Structural Biology, VIB Brussels Belgium
- Structural Biology Brussels Vrije Universiteit Brussel Brussels Belgium
| | - Han Remaut
- Structural and Molecular Microbiology VIB‐VUB Center for Structural Biology, VIB Brussels Belgium
- Structural Biology Brussels Vrije Universiteit Brussel Brussels Belgium
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26
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Jin C, Barone A, Borén T, Teneberg S. Helicobacter pylori-binding nonacid glycosphingolipids in the human stomach. J Biol Chem 2018; 293:17248-17266. [PMID: 30232154 DOI: 10.1074/jbc.ra118.004854] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 09/13/2018] [Indexed: 01/06/2023] Open
Abstract
Helicobacter pylori has a number of well-characterized carbohydrate-binding adhesins (BabA, SabA, and LabA) that promote adhesion to the gastric mucosa. In contrast, information on the glycoconjugates present in the human stomach remains unavailable. Here, we used MS and binding of carbohydrate-recognizing ligands to characterize the glycosphingolipids of three human stomachs from individuals with different blood group phenotypes (O(Rh-)P, A(Rh+)P, and A(Rh+)p), focusing on compounds recognized by H. pylori We observed a high degree of structural complexity, and the composition of glycosphingolipids differed among individuals with different blood groups. The type 2 chain was the dominating core chain of the complex glycosphingolipids in the human stomach, in contrast to the complex glycosphingolipids in the human small intestine, which have mainly a type 1 core. H. pylori did not bind to the O(Rh-)P stomach glycosphingolipids, whose major complex glycosphingolipids were neolactotetraosylceramide, the Lex, Lea, and H type 2 pentaosylceramides, and the Ley hexaosylceramide. Several H. pylori-binding compounds were present among the A(Rh+)P and A(Rh+)p stomach glycosphingolipids. Ligands for BabA-mediated binding of H. pylori were the Leb hexaosylceramide, the H type 1 pentaosylceramide, and the A type 1/ALeb heptaosylceramide. Additional H. pylori-binding glycosphingolipids recognized by BabA-deficient strains were lactosylceramide, lactotetraosylceramide, the x2 pentaosylceramide, and neolactohexaosylceramide. Our characterization of human gastric receptors required for H. pylori adhesion provides a basis for the development of specific compounds that inhibit the binding of this bacterium to the human gastric mucosa.
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Affiliation(s)
- Chunsheng Jin
- From the Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, P.O. Box 440, University of Gothenburg, SE-405 30 Göteborg, Sweden and
| | - Angela Barone
- From the Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, P.O. Box 440, University of Gothenburg, SE-405 30 Göteborg, Sweden and
| | - Thomas Borén
- the Department of Medical Biochemistry and Biophysics, Umeå University, SE-90187 Umeå, Sweden
| | - Susann Teneberg
- From the Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, P.O. Box 440, University of Gothenburg, SE-405 30 Göteborg, Sweden and .,the Department of Medical Biochemistry and Biophysics, Umeå University, SE-90187 Umeå, Sweden
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27
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Frequency of Helicobacter pylori hopQI, hopQII and sabA Genes Among Iranian Patients with Gastroduodenal Diseases. Jundishapur J Microbiol 2018. [DOI: 10.5812/jjm.56017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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28
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Zhao H, Xu L, Rong Q, Xu Z, Ding Y, Zhang Y, Wu Y, Li B, Ji X. Application of methylation in improving plasmid transformation into Helicobacter pylori. J Microbiol Methods 2018; 150:18-23. [DOI: 10.1016/j.mimet.2018.05.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2018] [Revised: 05/21/2018] [Accepted: 05/22/2018] [Indexed: 01/18/2023]
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29
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Gutiérrez-Escobar AJ, Méndez-Callejas G, Acevedo O, Bravo MM. Rapid evolution of the Helicobacter pylori AlpA adhesin in a high gastric cancer risk region from Colombia. PeerJ 2018; 6:e4846. [PMID: 29844987 PMCID: PMC5971833 DOI: 10.7717/peerj.4846] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 05/06/2018] [Indexed: 12/13/2022] Open
Abstract
To be able to survive, Helicobacter pylori must adhere to the gastric epithelial cells of its human host. For this purpose, the bacterium employs an array of adhesins, for example, AlpA. The adhesin AlpA has been proposed as a major adhesin because of its critical role in human stomach colonization. Therefore, understanding how AlpA evolved could be important for the development of new diagnostic strategies. However, the genetic variation and microevolutionary patterns of alpA have not been described in Colombia. The study aim was to describe the variation patterns and microevolutionary process of alpA in Colombian clinical isolates of H. pylori. The existing polymorphisms, which are deviations from the neutral model of molecular evolution, and the genetic differentiation of the alpA gene from Colombian clinical isolates of H. pylori were determined. The analysis shows that gene conversion and purifying selection have shaped the evolution of three different variants of alpA in Colombia.
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Affiliation(s)
- Andrés Julián Gutiérrez-Escobar
- Grupo de Investigaciones Biomédicas y Genética Humana Aplicada-GIBGA, Programa de medicina, Universidad de Ciencias Aplicadas y Ambientales U.D.C.A., Bogotá, Colombia.,Doctorado en Ciencias Biológicas, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Gina Méndez-Callejas
- Grupo de Investigaciones Biomédicas y Genética Humana Aplicada-GIBGA, Programa de medicina, Universidad de Ciencias Aplicadas y Ambientales U.D.C.A., Bogotá, Colombia
| | - Orlando Acevedo
- Grupo de Biofísica y Bioquímica Estructural, Facultad de Ciencias, Pontifica Universidad Javeriana, Bogotá, Colombia
| | - Maria Mercedes Bravo
- Grupo de Investigación en Biología del Cáncer, Instituto Nacional de Cancerología de Colombia, Bogotá, Colombia
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30
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Beckett AC, Loh JT, Chopra A, Leary S, Lin AS, McDonnell WJ, Dixon BREA, Noto JM, Israel DA, Peek RM, Mallal S, Algood HMS, Cover TL. Helicobacter pylori genetic diversification in the Mongolian gerbil model. PeerJ 2018; 6:e4803. [PMID: 29796347 PMCID: PMC5961626 DOI: 10.7717/peerj.4803] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 04/30/2018] [Indexed: 12/12/2022] Open
Abstract
Helicobacter pylori requires genetic agility to infect new hosts and establish long-term colonization of changing gastric environments. In this study, we analyzed H. pylori genetic adaptation in the Mongolian gerbil model. This model is of particular interest because H. pylori-infected gerbils develop a high level of gastric inflammation and often develop gastric adenocarcinoma or gastric ulceration. We analyzed the whole genome sequences of H. pylori strains cultured from experimentally infected gerbils, in comparison to the genome sequence of the input strain. The mean annualized single nucleotide polymorphism (SNP) rate per site was 1.5e−5, which is similar to the rates detected previously in H. pylori-infected humans. Many of the mutations occurred within or upstream of genes associated with iron-related functions (fur, tonB1, fecA2, fecA3, and frpB3) or encoding outer membrane proteins (alpA, oipA, fecA2, fecA3, frpB3 and cagY). Most of the SNPs within coding regions (86%) were non-synonymous mutations. Several deletion or insertion mutations led to disruption of open reading frames, suggesting that the corresponding gene products are not required or are deleterious during chronic H. pylori colonization of the gerbil stomach. Five variants (three SNPs and two deletions) were detected in isolates from multiple animals, which suggests that these mutations conferred a selective advantage. One of the mutations (FurR88H) detected in isolates from multiple animals was previously shown to confer increased resistance to oxidative stress, and we now show that this SNP also confers a survival advantage when H. pylori is co-cultured with neutrophils. Collectively, these analyses allow the identification of mutations that are positively selected during H. pylori colonization of the gerbil model.
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Affiliation(s)
- Amber C Beckett
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - John T Loh
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Abha Chopra
- Institute for Immunology and Infectious Diseases, Murdoch University, Murdoch, Australia
| | - Shay Leary
- Institute for Immunology and Infectious Diseases, Murdoch University, Murdoch, Australia
| | - Aung Soe Lin
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Wyatt J McDonnell
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Beverly R E A Dixon
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Jennifer M Noto
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Dawn A Israel
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Richard M Peek
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, United States of America.,Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Simon Mallal
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, United States of America.,Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America.,Institute for Immunology and Infectious Diseases, Murdoch University, Murdoch, Australia
| | - Holly M Scott Algood
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America.,Tennessee Valley Healthcare System, Veterans Affairs, Nashville, TN, United States of America
| | - Timothy L Cover
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, United States of America.,Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America.,Tennessee Valley Healthcare System, Veterans Affairs, Nashville, TN, United States of America
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31
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Bonsor DA, Zhao Q, Schmidinger B, Weiss E, Wang J, Deredge D, Beadenkopf R, Dow B, Fischer W, Beckett D, Wintrode PL, Haas R, Sundberg EJ. The Helicobacter pylori adhesin protein HopQ exploits the dimer interface of human CEACAMs to facilitate translocation of the oncoprotein CagA. EMBO J 2018; 37:embj.201798664. [PMID: 29724755 DOI: 10.15252/embj.201798664] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 03/27/2018] [Accepted: 04/05/2018] [Indexed: 01/06/2023] Open
Abstract
Helicobacter pylori infects half of the world's population, and strains that encode the cag type IV secretion system for injection of the oncoprotein CagA into host gastric epithelial cells are associated with elevated levels of cancer. CagA translocation into host cells is dependent on interactions between the H. pylori adhesin protein HopQ and human CEACAMs. Here, we present high-resolution structures of several HopQ-CEACAM complexes and CEACAMs in their monomeric and dimeric forms establishing that HopQ uses a coupled folding and binding mechanism to engage the canonical CEACAM dimerization interface for CEACAM recognition. By combining mutagenesis with biophysical and functional analyses, we show that the modes of CEACAM recognition by HopQ and CEACAMs themselves are starkly different. Our data describe precise molecular mechanisms by which microbes exploit host CEACAMs for infection and enable future development of novel oncoprotein translocation inhibitors and H. pylori-specific antimicrobial agents.
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Affiliation(s)
- Daniel A Bonsor
- Institute of Human Virology, University of Maryland School of Medicine, University of Maryland, Baltimore, MD, USA
| | - Qing Zhao
- Chair of Medical Microbiology and Hospital Epidemiology, Max von Pettenkofer Institute, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Barbara Schmidinger
- Chair of Medical Microbiology and Hospital Epidemiology, Max von Pettenkofer Institute, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Evelyn Weiss
- Chair of Medical Microbiology and Hospital Epidemiology, Max von Pettenkofer Institute, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Jingheng Wang
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, USA
| | - Daniel Deredge
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, MD, USA
| | - Robert Beadenkopf
- Institute of Human Virology, University of Maryland School of Medicine, University of Maryland, Baltimore, MD, USA
| | - Blaine Dow
- Institute of Human Virology, University of Maryland School of Medicine, University of Maryland, Baltimore, MD, USA
| | - Wolfgang Fischer
- Chair of Medical Microbiology and Hospital Epidemiology, Max von Pettenkofer Institute, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Dorothy Beckett
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, USA
| | - Patrick L Wintrode
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, MD, USA
| | - Rainer Haas
- Chair of Medical Microbiology and Hospital Epidemiology, Max von Pettenkofer Institute, Faculty of Medicine, LMU Munich, Munich, Germany.,German Center for Infection Research (DZIF), Partner Site LMU, Munich, Germany
| | - Eric J Sundberg
- Institute of Human Virology, University of Maryland School of Medicine, University of Maryland, Baltimore, MD, USA .,Department of Medicine, University of Maryland School of Medicine, University of Maryland, Baltimore, MD, USA.,Department of Microbiology and Immunology, University of Maryland School of Medicine, University of Maryland, Baltimore, MD, USA
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32
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Ansari S, Yamaoka Y. Helicobacter pylori BabA in adaptation for gastric colonization. World J Gastroenterol 2017; 23:4158-4169. [PMID: 28694656 PMCID: PMC5483490 DOI: 10.3748/wjg.v23.i23.4158] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2017] [Revised: 04/12/2017] [Accepted: 06/01/2017] [Indexed: 02/06/2023] Open
Abstract
Helicobacter pylori (H. pylori) as a causative agent of gastric complications, is well adapted for the colonization of gastric mucosa. Although the infectious process depends on several factors, the adhesion to the gastric mucosa is the first and important step. Among several outer membrane proteins, BabA is one of the significant protein involving in many inflammatory processes in addition to its role in the attachment for the persistent colonization. We performed a PubMed search using the key words: “babA”, “pylori”, “gastric complications”, “homologous recombination”, “slipped strand mispairing”; a total of 249 articles were displayed. Of these we mainly focused on articles with the full text in English and published between 2005 and 2016. H. pylori BabA is involved in binding with receptors; however, its synthesis is regulated by phase variation. In this review we confirm that H. pylori babA can be modulated at the molecular and functional levels to adapt to the stress within the gastro-intestinal tract.
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33
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How do they stick together? Bacterial adhesins implicated in the binding of bacteria to the human gastrointestinal mucins. Biochem Soc Trans 2017; 45:389-399. [PMID: 28408479 DOI: 10.1042/bst20160167] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 12/16/2016] [Accepted: 01/23/2017] [Indexed: 01/04/2023]
Abstract
The gastrointestinal mucosal surface is the primary interface between internal host tissues and the vast microbiota. Mucins, key components of mucus, are high-molecular-weight glycoproteins characterized by the presence of many O-linked oligosaccharides to the core polypeptide. They play many biological functions, helping to maintain cellular homeostasis and to establish symbiotic relationships with complex microbiota. Mucin O-glycans exhibit a huge variety of peripheral sequences implicated in the binding of bacteria to the mucosal tissues, thereby playing a key role in the selection of specific species and in the tissue tropism displayed by commensal and pathogenic bacteria. Bacteria have evolved numerous strategies to colonize host mucosae, and among these are modulation of expression of cell surface adhesins which allow bacteria to bind to mucins. However, despite well structurally characterized adhesins and lectins, information on the nature and structure of oligosaccharides recognized by bacteria is still disparate. This review summarizes the current knowledge on the structure of epithelial mucin O-glycans and the interaction between host and commensal or pathogenic bacteria mediated by mucins.
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34
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Matsuo Y, Kido Y, Yamaoka Y. Helicobacter pylori Outer Membrane Protein-Related Pathogenesis. Toxins (Basel) 2017; 9:toxins9030101. [PMID: 28287480 PMCID: PMC5371856 DOI: 10.3390/toxins9030101] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 03/08/2017] [Accepted: 03/09/2017] [Indexed: 12/16/2022] Open
Abstract
Helicobacter pylori colonizes the human stomach and induces inflammation, and in some cases persistent infection can result in gastric cancer. Attachment to the gastric mucosa is the first step in establishing bacterial colonization, and outer membrane proteins (OMPs) play a pivotal role in binding to human cells. Some OMP interaction molecules are known in H. pylori, and their associated host cell responses have been gradually clarified. Many studies have demonstrated that OMPs are essential to CagA translocation into gastric cells via the Type IV secretion system of H. pylori. This review summarizes the mechanisms through which H. pylori utilizes OMPs to colonize the human stomach and how OMPs cooperate with the Type IV secretion system.
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Affiliation(s)
- Yuichi Matsuo
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, 1-1 Idaigaoka, Hasama-Machi, Yufu-City, Oita 879-5593, Japan.
| | - Yasutoshi Kido
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, 1-1 Idaigaoka, Hasama-Machi, Yufu-City, Oita 879-5593, Japan.
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, 1-1 Idaigaoka, Hasama-Machi, Yufu-City, Oita 879-5593, Japan.
- Department of Medicine-Gastroenterology, Michael E. DeBakey Veterans Affairs Medical Center and Baylor College of Medicine, Houston, TX 77030, USA.
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35
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Diversification of the AlpB Outer Membrane Protein of Helicobacter pylori Affects Biofilm Formation and Cellular Adhesion. J Bacteriol 2017; 199:JB.00729-16. [PMID: 28031283 PMCID: PMC5331671 DOI: 10.1128/jb.00729-16] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 12/19/2016] [Indexed: 02/07/2023] Open
Abstract
Helicobacter pylori is one of the most common causes of bacterial infection in humans, and it forms biofilms on human gastric mucosal epithelium as well as on in vitro abiotic surfaces. Bacterial biofilm is critical not only for environmental survival but also for successful infection. We previously demonstrated that strain TK1402, which was isolated from a Japanese patient with duodenal and gastric ulcers, has high biofilm-forming ability in vitro relative to other strains. In addition, we showed that outer membrane vesicles (OMV) play an important role in biofilm formation. The aim of this study was to analyze which protein(s) in the OMV contributes to biofilm formation in TK1402. We obtained a spontaneous mutant strain derived from TK1402 lacking biofilm-forming ability. The protein profiles of the OMV were compared between this mutant strain and the wild type, and it was found that AlpB, an outer membrane protein in the OMV of the mutant strain, was markedly decreased compared to that of the wild type. Restoration of TK1402 alpB to the mutant strain fully recovered the ability to form biofilm. However, restoration with alpB from other strains demonstrated incomplete recovery of biofilm-forming ability. We therefore inferred that the variable region of AlpB (amino acid positions 121 to 146) was involved in TK1402 biofilm formation. In addition, diversification of the AlpB sequence was shown to affect the ability to adhere to AGS cells. These results demonstrate a new insight into the molecular mechanisms of host colonization by H. pylori. IMPORTANCE Bacterial biofilm is critical not only for environmental survival but also for successful infection. The mechanism of Helicobacter pylori adherence to host cells mediated by cell surface adhesins has been the focus of many studies, but little is known regarding factors involved in H. pylori biofilm formation. Our study demonstrated that AlpB plays an important role in biofilm formation and that this property depends upon the specific sequence of alpB. This in turn was shown to be important in the ability to adhere to gastric cells. We anticipate that these results will provide new insight into the molecular mechanisms of H. pylori colonization.
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Thorell K, Yahara K, Berthenet E, Lawson DJ, Mikhail J, Kato I, Mendez A, Rizzato C, Bravo MM, Suzuki R, Yamaoka Y, Torres J, Sheppard SK, Falush D. Rapid evolution of distinct Helicobacter pylori subpopulations in the Americas. PLoS Genet 2017; 13:e1006546. [PMID: 28231283 PMCID: PMC5322909 DOI: 10.1371/journal.pgen.1006546] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 12/19/2016] [Indexed: 12/13/2022] Open
Abstract
For the last 500 years, the Americas have been a melting pot both for genetically diverse humans and for the pathogenic and commensal organisms associated with them. One such organism is the stomach-dwelling bacterium Helicobacter pylori, which is highly prevalent in Latin America where it is a major current public health challenge because of its strong association with gastric cancer. By analyzing the genome sequence of H. pylori isolated in North, Central and South America, we found evidence for admixture between H. pylori of European and African origin throughout the Americas, without substantial input from pre-Columbian (hspAmerind) bacteria. In the US, strains of African and European origin have remained genetically distinct, while in Colombia and Nicaragua, bottlenecks and rampant genetic exchange amongst isolates have led to the formation of national gene pools. We found three outer membrane proteins with atypical levels of Asian ancestry in American strains, as well as alleles that were nearly fixed specifically in South American isolates, suggesting a role for the ethnic makeup of hosts in the colonization of incoming strains. Our results show that new H. pylori subpopulations can rapidly arise, spread and adapt during times of demographic flux, and suggest that differences in transmission ecology between high and low prevalence areas may substantially affect the composition of bacterial populations. Helicobacter pylori is one of the best studied examples of an intimate association between bacteria and humans, due to its ability to colonize the stomach for decades and to transmit from generation to generation. A number of studies have sought to link diversity in H. pylori to human migrations but there are some discordant signals such as an “out of Africa” dispersal within the last few thousand years that has left a much stronger signal in bacterial genomes than in human ones. In order to understand how such discrepancies arise, we have investigated the evolution of H. pylori during the recent colonization of the Americas. We find that bacterial populations evolve quickly and can spread rapidly to people of different ethnicities. Distinct new bacterial subpopulations have formed in Colombia from a European source and in Nicaragua and the US from African sources. Genetic exchange between bacterial populations is rampant within Central and South America but is uncommon within North America, which may reflect differences in prevalence. Our results also suggest that adaptation of bacteria to particular human ethnic groups may be confined to a handful of genes involved in interaction with the immune system.
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Affiliation(s)
- Kaisa Thorell
- Microbiology, Tumour and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Koji Yahara
- Dept. of Bacteriology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Elvire Berthenet
- Medical Microbiology and Infectious Disease group, Swansea University, Swansea, Wales, United Kingdom
| | - Daniel J. Lawson
- Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom
| | - Jane Mikhail
- Medical Microbiology and Infectious Disease group, Swansea University, Swansea, Wales, United Kingdom
| | - Ikuko Kato
- Karmanos Cancer Institute, Wayne State University, Detroit, Michigan, United States of America
| | - Alfonso Mendez
- Instituto Politecnico Nacional, ENCB, Mexico City, Mexico
| | - Cosmeri Rizzato
- Dipartimento di Ricerca Traslazionale e Nuove Tecnologie in Medicina e Chirurgia, Universitá di Pisa, Pisa, Italy
| | - María Mercedes Bravo
- Grupo de Investigación en Biología del Cáncer, Instituto Nacional de Cancerología, Bogota, Colombia
| | - Rumiko Suzuki
- Dept. of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Oita, Japan
| | - Yoshio Yamaoka
- Dept. of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Oita, Japan
| | - Javier Torres
- Unidad de Investigación en Enfermedades Infecciosas, UMAE Pediatria, IMSS, Mexico City, Mexico
| | - Samuel K. Sheppard
- Milner Center for Evolution, Dept. of Biology and Biochemistry, University of Bath, Bath, United Kingdom
| | - Daniel Falush
- Milner Center for Evolution, Dept. of Biology and Biochemistry, University of Bath, Bath, United Kingdom
- * E-mail:
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Cheng L, Mirko R, Sara L, Medea P, Caroline B, Eva B, Myrthe J, Bram F, Wim VDB, Richard D, Freddy H, Annemieke S. The Helicobacter heilmannii hofE and hofF Genes are Essential for Colonization of the Gastric Mucosa and Play a Role in IL-1β-Induced Gastric MUC13 Expression. Helicobacter 2016; 21:504-522. [PMID: 26935145 DOI: 10.1111/hel.12307] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Helicobacter heilmannii is a zoonotic bacterium associated with gastric disease in humans. We recently showed that H. heilmannii binds to human gastric mucins and epithelial cells and highlighted a potential role for the murine Muc13 mucin in gastric Helicobacter colonization. The aims of this study were to investigate the role of the H. heilmannii hof gene locus encoding HofH/F/E/G/C/D in adhesion to the gastric mucosa and induction of increased gastric Muc13 expression. METHODS Bacterial hof gene and host gene expression experiments, Helicobacter binding assays and experimental infection studies in mice were performed. H. pylori and its ΔhofF mutant were included for comparison. RESULTS Helicobacter heilmannii strains lacking HofE or HofF showed a clear decrease in binding to gastric mucins and epithelial cells as well as a lower gastric colonization level in the stomach of Balb/c mice at 4 and 9 weeks post-infection compared to the H. heilmannii wildtype strain. Interestingly, H. heilmannii ΔhofE and ΔhofF and H. pylori ΔhofF did not induce an increased expression of MUC13 in human gastric epithelial cells and of Muc13 in the stomach of mice. Finally, we demonstrated that IL-1β is induced in the stomach as a response to Helicobacter colonization which on its turn is involved in the expression of MUC13/Muc13 in the gastric epithelium. CONCLUSION These novel results in Helicobacter research identified H. heilmannii HofE and HofF as adhesins and suggest an important role of H. heilmannii HofE and HofF and H. pylori HofF in IL-1β-induced gastric MUC13/Muc13 expression.
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Affiliation(s)
- Liu Cheng
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Rossi Mirko
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
| | - Lindén Sara
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Padra Medea
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Blaecher Caroline
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Bauwens Eva
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Joosten Myrthe
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Flahou Bram
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Van den Broeck Wim
- Department of Morphology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Ducatelle Richard
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Haesebrouck Freddy
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Smet Annemieke
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
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Huang Y, Wang QL, Cheng DD, Xu WT, Lu NH. Adhesion and Invasion of Gastric Mucosa Epithelial Cells by Helicobacter pylori. Front Cell Infect Microbiol 2016; 6:159. [PMID: 27921009 PMCID: PMC5118847 DOI: 10.3389/fcimb.2016.00159] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Accepted: 11/04/2016] [Indexed: 12/11/2022] Open
Abstract
Helicobacter pylori is the main pathogenic bacterium involved in chronic gastritis and peptic ulcer and a class 1 carcinogen in gastric cancer. Current research focuses on the pathogenicity of H. pylori and the mechanism by which it colonizes the gastric mucosa. An increasing number of in vivo and in vitro studies demonstrate that H. pylori can invade and proliferate in epithelial cells, suggesting that this process might play an important role in disease induction, immune escape and chronic infection. Therefore, to explore the process and mechanism of adhesion and invasion of gastric mucosa epithelial cells by H. pylori is particularly important. This review examines the relevant studies and describes evidence regarding the adhesion to and invasion of gastric mucosa epithelial cells by H. pylori.
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Affiliation(s)
- Ying Huang
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University Nanchang, China
| | - Qi-Long Wang
- Department of General Surgery, Tianjin Haihe Hospital Tianjin, China
| | - Dan-Dan Cheng
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University Nanchang, China
| | - Wen-Ting Xu
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University Nanchang, China
| | - Nong-Hua Lu
- Department of Gastroenterology, The First Affiliated Hospital of Nanchang University Nanchang, China
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Wiedemann T, Hofbaur S, Loell E, Rieder G. A C-Terminal Coiled-Coil Region of CagL is Responsible for Helicobacter Pylori-Induced Il-8 Expression. Eur J Microbiol Immunol (Bp) 2016; 6:186-196. [PMID: 27766167 PMCID: PMC5063011 DOI: 10.1556/1886.2016.00020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 06/07/2016] [Indexed: 02/07/2023] Open
Abstract
Interleukin-8 (IL-8) is a potent neutrophil-activating chemokine which triggers the infiltration and migration of neutrophils into areas of bacterial infection. Helicobacter pylori-infected patient studies as well as animal models have revealed that H. pylori type I strains carrying an intact cytotoxin-associated gene pathogenicity island (cag-PAI) with a functional type IV secretion system (T4SS) induce IL-8 expression and secretion in gastric mucosa. This gastric mucosal IL-8 expression correlates with severe histological changes due to H. pylori infection. In the present study, we explored a new recognition pattern on the bacterial adhesion protein CagL inducing IL-8 expression in H. pylori-infected host cells. To analyze the secreted IL-8 concentration, we performed IL-8 enzyme-linked immunosorbent assay (ELISA). To investigate the H. pylori-induced IL-8 expression on the transcriptional level, we transiently transfected gastric epithelial cells (AGS) with a human IL-8 luciferase reporter construct. The results of this study demonstrate that specifically the C-terminal coiled-coil region of the H. pylori CagL protein, a protein described to be located on the tip of the T4SS-pilus, is responsible for several in vitro observations: 1) H. pylori-induced IL-8 secretion via the transforming growth factor (TGF)-α activated epidermal growth factor-receptor (EGF-R) signaling pathway; 2) H. pylori-induced elongation of the cells, a typical CagA-induced phenotype; and 3) the bridging of the T4SS to its human target cells. This novel bacterial-host recognition sequence allows a new insight into how H. pylori induces the inflammatory response in gastric epithelial cells and facilitates the development of precancerous conditions.
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Affiliation(s)
- Tobias Wiedemann
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute for Diabetes and Cancer , Neuherberg, Germany
| | - Stefan Hofbaur
- Max-von-Pettenkofer-Institute for Hygiene and Medical Microbiology, Ludwig Maximilians University , Munich, Germany
| | - Eva Loell
- Max-von-Pettenkofer-Institute for Hygiene and Medical Microbiology, Ludwig Maximilians University , Munich, Germany
| | - Gabriele Rieder
- Bavarian Health and Food Safety Authority, Veterinaerstrasse 2 , D-85764 Oberschleissheim, Germany
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Kao CY, Sheu BS, Wu JJ. Helicobacter pylori infection: An overview of bacterial virulence factors and pathogenesis. Biomed J 2016; 39:14-23. [PMID: 27105595 PMCID: PMC6138426 DOI: 10.1016/j.bj.2015.06.002] [Citation(s) in RCA: 248] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 06/08/2015] [Indexed: 12/16/2022] Open
Abstract
Helicobacter pylori pathogenesis and disease outcomes are mediated by a complex interplay between bacterial virulence factors, host, and environmental factors. After H. pylori enters the host stomach, four steps are critical for bacteria to establish successful colonization, persistent infection, and disease pathogenesis: (1) Survival in the acidic stomach; (2) movement toward epithelium cells by flagella-mediated motility; (3) attachment to host cells by adhesins/receptors interaction; (4) causing tissue damage by toxin release. Over the past 20 years, the understanding of H. pylori pathogenesis has been improved by studies focusing on the host and bacterial factors through epidemiology researches and molecular mechanism investigations. These include studies identifying the roles of novel virulence factors and their association with different disease outcomes, especially the bacterial adhesins, cag pathogenicity island, and vacuolating cytotoxin. Recently, the development of large-scale screening methods, including proteomic, and transcriptomic tools, has been used to determine the complex gene regulatory networks in H. pylori. In addition, a more available complete genomic database of H. pylori strains isolated from patients with different gastrointestinal diseases worldwide is helpful to characterize this bacterium. This review highlights the key findings of H. pylori virulence factors reported over the past 20 years.
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Affiliation(s)
- Cheng-Yen Kao
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Bor-Shyang Sheu
- Department of Internal Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Jiunn-Jong Wu
- Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Center of Infectious Disease and Signaling Research, National Cheng Kung University, Tainan, Taiwan; Department of Biotechnology and Laboratory Science in Medicine, School of Biomedical Science and Engineering, National Yang-Ming University, Taipei, Taiwan.
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Leylabadlo HE, Yekani M, Ghotaslou R. Helicobacter pylori hopQ alleles (type I and II) in gastric cancer. Biomed Rep 2016; 4:601-604. [PMID: 27123254 DOI: 10.3892/br.2016.634] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/02/2016] [Indexed: 01/24/2023] Open
Abstract
The Helicobacter pylori (H. pylori) outer membrane protein (HopQ) of is one of the proteins involved in bacterial adherence to gastric mucosa and has been suggested to have a role in the virulence of H. pylori. The aim of the present study was to determine the association between H. pylori virulence types I and II hopQ genotypes and patients with different gastrointestinal diseases. A polymerase chain reaction-based assay was used to determine the presence of type I and type II hopQ genes in 88 H. pylori strains isolated from H. pylori-infected patients. Of the total 88 H. pylori isolates, type I and type II hopQ alleles were detected in 52 (59.1%) and 36 (40.9%), respectively. A significant association was found between type I hopQ gene and gastric cancer [odds ratio, 2.3; 95% confidence interval (CI), 1.3-4.1] and gastric ulcers (odds ratio, 2.5; 95% CI, 1.4-4.3). A significant association was also identified between the type II hopQ gene and gastric cancer (odds ratio, 2.4; 95% CI, 1.1-3.0). The association between hopQ type I and hopQ type II genotypes and clinical status suggest that these genes may be helpful in the universal prediction of specific disease risks.
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Affiliation(s)
| | - Mina Yekani
- Department of Microbiology, School of Medicine, Tabriz University of Medical Sciences, Tabriz 51664-14766, Iran
| | - Reza Ghotaslou
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz 51636-39888, Iran; Department of Microbiology, School of Medicine, Tabriz University of Medical Sciences, Tabriz 51664-14766, Iran
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Jiménez-Soto LF, Haas R. The CagA toxin of Helicobacter pylori: abundant production but relatively low amount translocated. Sci Rep 2016; 6:23227. [PMID: 26983895 PMCID: PMC4794710 DOI: 10.1038/srep23227] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 03/02/2016] [Indexed: 02/07/2023] Open
Abstract
CagA is one of the most studied pathogenicity factors of the bacterial pathogen Helicobacter pylori. It is injected into host cells via the H. pylori cag-Type IV secretion system. Due to its association with gastric cancer, CagA is classified as oncogenic protein. At the same time CagA represents the 4th most abundant protein produced by H. pylori, suggesting that high amounts of toxin are required to cause the physiological changes or damage observed in cells. We were able to quantify the injection of CagA into gastric AGS epithelial cells in vitro by the adaptation of a novel protease-based approach to remove the tightly adherent extracellular bacteria. After one hour of infection only 1.5% of the total CagA available was injected by the adherent bacteria, whereas after 3 hours 7.5% was found within the host cell. Thus, our data show that only a surprisingly small amount of the CagA available in the infection is finally injected under in vitro infection conditions.
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Affiliation(s)
- Luisa F Jiménez-Soto
- Max von Pettenkofer-Institut für Hygiene und Medizinische Mikrobiologie, Ludwig-Maximilians-Universität, Pettenkoferstraße 9a, D-80336 München, Germany
| | - Rainer Haas
- Max von Pettenkofer-Institut für Hygiene und Medizinische Mikrobiologie, Ludwig-Maximilians-Universität, Pettenkoferstraße 9a, D-80336 München, Germany.,German Center for Infection Research (DZIF), LMU Munich, Germany
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Keilberg D, Ottemann KM. HowHelicobacter pylorisenses, targets and interacts with the gastric epithelium. Environ Microbiol 2016; 18:791-806. [DOI: 10.1111/1462-2920.13222] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Revised: 01/05/2016] [Accepted: 01/10/2016] [Indexed: 12/18/2022]
Affiliation(s)
- Daniela Keilberg
- Department of Microbiology and Environmental Toxicology; University of California Santa Cruz; 1156 High Street METX Santa Cruz CA 95064 USA
| | - Karen M. Ottemann
- Department of Microbiology and Environmental Toxicology; University of California Santa Cruz; 1156 High Street METX Santa Cruz CA 95064 USA
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Wilson MM, Bernstein HD. Surface-Exposed Lipoproteins: An Emerging Secretion Phenomenon in Gram-Negative Bacteria. Trends Microbiol 2015; 24:198-208. [PMID: 26711681 DOI: 10.1016/j.tim.2015.11.006] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 11/17/2015] [Accepted: 11/23/2015] [Indexed: 01/07/2023]
Abstract
Bacterial lipoproteins are hydrophilic proteins that are anchored to a cell membrane by N-terminally linked fatty acids. It is widely believed that nearly all lipoproteins produced by Gram-negative bacteria are either retained in the inner membrane (IM) or transferred to the inner leaflet of the outer membrane (OM). Lipoproteins that are exposed on the cell surface have also been reported but are generally considered to be rare. Results from a variety of recent studies, however, now suggest that the prevalence of surface-exposed lipoproteins has been underestimated. In this review we describe the evidence that the surface exposure of lipoproteins in Gram-negative bacteria is a widespread phenomenon and discuss possible mechanisms by which these proteins might be transported across the OM.
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Affiliation(s)
- Marlena M Wilson
- Genetics and Biochemistry Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Harris D Bernstein
- Genetics and Biochemistry Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
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Yakoob J, Abbas Z, Khan R, Salim SA, Awan S, Abrar A, Jafri W. Helicobacter pylori outer membrane protein Q allele distribution is associated with distinct pathologies in Pakistan. INFECTION GENETICS AND EVOLUTION 2015; 37:57-62. [PMID: 26516025 DOI: 10.1016/j.meegid.2015.10.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 10/12/2015] [Accepted: 10/26/2015] [Indexed: 12/15/2022]
Abstract
Helicobacter pylori (H. pylori) strains expressing outer membrane protein Q (HopQ) promote adherence to the gastric epithelial cell. We characterized HopQ alleles in relation to H. pylori-related disease, histology and virulence markers. Gastric biopsies were obtained at esophagogastroduodenoscopy from patients with upper gastrointestinal symptoms. H. pylori culture, histology and polymerase chain reaction (PCR) for HopQ types, cagA, cagA-promoter and vacA alleles were performed. DNA extracted was used for PCR. Sequencing of PCR products of HopQ types 1 and 2 was followed by BLAST query. We examined 241 H. pylori isolates. HopQ type 1 was positive in 70 (29%) isolates, type 2 in 60 (25%) isolates, while both type 1 and type 2 in 111 (46%) H. pylori isolates, respectively. Nonulcer dyspepsia (NUD) was associated with HopQ type 2 in 48 (41%) isolates, while gastric carcinoma (GC) in 37 (53%) (P<0.001) with type 1 isolates. Gastric ulcers (GU) were 39 (46%) (P<0.001) in H. pylori infection with multiple HopQ alleles compared to 6 (23%) in HopQ type 1. Multivariate analysis demonstrated that multiple HopQ alleles were associated with GU OR 2.9 (1.07-7.8) (P=0.03). HopQ type 1 was associated with cagA 58 (84%) (P<0.001) and cagA-promoter 58 (83%) (P<0.001) compared to 14 (23%) and 17 (28%) respectively, in type 2. VacAs1a was associated with HopQ type 1 in 59 (84%) isolates compared to HopQ type 2 in 35 (58%) (P=0.002) isolates. VacAm1 was associated with HopQ type 1 in 53 (76%) isolates compared to HopQ type 2 in 32 (53%) (P=0.004) isolates. H. pylori infection with multiple HopQ alleles was predominant. H. pylori infection with single HopQ type 1 was associated with GC in the presence of other H. pylori virulence markers.
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Affiliation(s)
- Javed Yakoob
- Department of Medicine, Aga Khan University, Karachi, Pakistan.
| | - Zaigham Abbas
- Department of Medicine, Aga Khan University, Karachi, Pakistan
| | - Rustam Khan
- Department of Medicine, Aga Khan University, Karachi, Pakistan
| | | | - Safia Awan
- Department of Medicine, Aga Khan University, Karachi, Pakistan
| | - Ambar Abrar
- Department of Medicine, Aga Khan University, Karachi, Pakistan
| | - Wasim Jafri
- Department of Medicine, Aga Khan University, Karachi, Pakistan
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Abstract
The autotransporter and two-partner secretion (TPS) pathways are used by E. coli and many other Gram-negative bacteria to delivervirulence factors into the extracellular milieu.Autotransporters arecomprised of an N-terminal extracellular ("passenger") domain and a C-terminal β barrel domain ("β domain") that anchors the protein to the outer membrane and facilitates passenger domain secretion. In the TPS pathway, a secreted polypeptide ("exoprotein") is coordinately expressed with an outer membrane protein that serves as a dedicated transporter. Bothpathways are often grouped together under the heading "type V secretion" because they have many features in common and are used for the secretion of structurally related polypeptides, but it is likely that theyhave distinct evolutionary origins. Although it was proposed many years ago that autotransporterpassenger domains are transported across the outer membrane through a channel formed by the covalently linked β domain, there is increasing evidence that additional factors are involved in the translocation reaction. Furthermore, details of the mechanism of protein secretion through the TPS pathway are only beginning to emerge. In this chapter I discussour current understanding ofboth early and late steps in the biogenesis of polypeptides secreted through type V pathways and current modelsofthe mechanism of secretion.
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Dwivedi P, Alam SI, Kumar O, Kumar RB. Lipoproteins from Clostridium perfringens and their protective efficacy in mouse model. INFECTION GENETICS AND EVOLUTION 2015; 34:434-43. [DOI: 10.1016/j.meegid.2015.05.029] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 05/27/2015] [Accepted: 05/28/2015] [Indexed: 01/10/2023]
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Helicobacter pylori Outer Membrane Protein 18 (Hp1125) Is Involved in Persistent Colonization by Evading Interferon- γ Signaling. BIOMED RESEARCH INTERNATIONAL 2015; 2015:571280. [PMID: 25945338 PMCID: PMC4402576 DOI: 10.1155/2015/571280] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 10/09/2014] [Accepted: 10/23/2014] [Indexed: 12/30/2022]
Abstract
Outer membrane proteins (OMPs) can induce an immune response. Omp18 (HP1125) of H. pylori is a powerful antigen that can induce significant interferon-γ (IFN-γ) levels. Previous studies have suggested that IFN-γ plays an important role in H. pylori clearance. However, H. pylori has multiple mechanisms to avoid host immune surveillance for persistent colonization. We generated an omp18 mutant (H. pylori 26695 and H. pylori SS1) strain to examine whether Omp18 interacts with IFN-γ and is involved in H. pylori colonization. qRT-PCR revealed that IFN-γ induced Omp18 expression. qRT-PCR and western blot analysis revealed reduced expressions of virulence factors CagA and NapA in H. pylori 26695 with IFN-γ treatment, but they were induced in the Δomp18 strain. In C57BL/6 mice infected with H. pylori SS1 and the Δomp18 strain, the Δomp18 strain conferred defective colonization and activated a stronger inflammatory response. Signal transducer phosphorylation and transcription 1 (STAT1) activator was downregulated by the wild-type strain but not the Δomp18 strain in IFN-γ-treated macrophages. Furthermore, Δomp18 strain survival rates were poor in macrophages compared to the wild-type strain. We concluded that H. pylori Omp18 has an important function influencing IFN-γ-mediated immune response to participate in persistent colonization.
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Krebes J, Didelot X, Kennemann L, Suerbaum S. Bidirectional genomic exchange between Helicobacter pylori strains from a family in Coventry, United Kingdom. Int J Med Microbiol 2014; 304:1135-46. [PMID: 25218701 DOI: 10.1016/j.ijmm.2014.08.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 08/06/2014] [Accepted: 08/10/2014] [Indexed: 02/08/2023] Open
Abstract
The human gastric pathogen Helicobacter pylori is characterised by a high mutation rate and frequent recombination during mixed infection, which result in extensive genetic diversity and rapid allelic diversification. Mixed infections are believed to be much more common in regions with a high H. pylori prevalence than in industrialised countries. To better understand the genomic flexibility of H. pylori in a low prevalence region, we used 454 sequencing technology to investigate whole genome sequences of H. pylori strains isolated from members of three generations of a family living in Coventry, UK. The genomes of four H. pylori strains isolated from a grandfather, two of his sons and one grandson were sequenced. Three of these genomes showed a high overall sequence similarity, suggesting a recent common ancestor. The genomes differed by 316-336 SNPs, and recombination events (imports) resulted in 170-251 clusters of polymorphisms (CNPs). Imports were particularly frequent in genes encoding Helicobacter outer membrane proteins, suggesting an adaptation of the strains to their individual host. The fourth strain differed substantially from these three highly related strains but still shared long fragments of identical sequence, which most likely reflect imports from the highly related family variants. The data show extensive bidirectional exchange of DNA between the strains isolated from the family members, illustrating both the convergence and divergence effect that recombination can lead to. Detailed analysis of the distribution of SNPs and imports permits to draw up a complex scenario of the transmission history involving infection with at least two, and probably more separate strains. This complexity and the resulting high frequency of recombination were unexpected for an industrialised country where the prevalence of H. pylori infection has strongly declined in recent decades.
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Affiliation(s)
- Juliane Krebes
- Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany; German Center for Infection Research, Hannover-Braunschweig Site, Carl-Neuberg-Straße 1, 30625 Hannover, Germany.
| | - Xavier Didelot
- Department of Infectious Disease Epidemiology, Imperial College London, London W2 1PG, United Kingdom.
| | - Lynn Kennemann
- Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
| | - Sebastian Suerbaum
- Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany; German Center for Infection Research, Hannover-Braunschweig Site, Carl-Neuberg-Straße 1, 30625 Hannover, Germany.
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van Ulsen P, Rahman SU, Jong WS, Daleke-Schermerhorn MH, Luirink J. Type V secretion: From biogenesis to biotechnology. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:1592-611. [DOI: 10.1016/j.bbamcr.2013.11.006] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 11/01/2013] [Accepted: 11/13/2013] [Indexed: 12/13/2022]
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