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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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Slusher GA, Kottke PA, Culberson AL, Chilmonczyk MA, Fedorov AG. Microfluidics enabled multi-omics triple-shot mass spectrometry for cell-based therapies. BIOMICROFLUIDICS 2024; 18:011302. [PMID: 38268742 PMCID: PMC10807926 DOI: 10.1063/5.0175178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 01/01/2024] [Indexed: 01/26/2024]
Abstract
In recent years, cell-based therapies have transformed medical treatment. These therapies present a multitude of challenges associated with identifying the mechanism of action, developing accurate safety and potency assays, and achieving low-cost product manufacturing at scale. The complexity of the problem can be attributed to the intricate composition of the therapeutic products: living cells with complex biochemical compositions. Identifying and measuring critical quality attributes (CQAs) that impact therapy success is crucial for both the therapy development and its manufacturing. Unfortunately, current analytical methods and tools for identifying and measuring CQAs are limited in both scope and speed. This Perspective explores the potential for microfluidic-enabled mass spectrometry (MS) systems to comprehensively characterize CQAs for cell-based therapies, focusing on secretome, intracellular metabolome, and surfaceome biomarkers. Powerful microfluidic sampling and processing platforms have been recently presented for the secretome and intracellular metabolome, which could be implemented with MS for fast, locally sampled screening of the cell culture. However, surfaceome analysis remains limited by the lack of rapid isolation and enrichment methods. Developing innovative microfluidic approaches for surface marker analysis and integrating them with secretome and metabolome measurements using a common analytical platform hold the promise of enhancing our understanding of CQAs across all "omes," potentially revolutionizing cell-based therapy development and manufacturing for improved efficacy and patient accessibility.
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Affiliation(s)
| | - Peter A. Kottke
- The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30318, USA
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3
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Jarzab M, Skorko-Glonek J. There Are No Insurmountable Barriers: Passage of the Helicobacter pylori VacA Toxin from Bacterial Cytoplasm to Eukaryotic Cell Organelle. MEMBRANES 2023; 14:11. [PMID: 38248700 PMCID: PMC10821523 DOI: 10.3390/membranes14010011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 12/20/2023] [Accepted: 12/23/2023] [Indexed: 01/23/2024]
Abstract
The Gram-negative bacterium Helicobacter pylori is a very successful pathogen, one of the most commonly identified causes of bacterial infections in humans worldwide. H. pylori produces several virulence factors that contribute to its persistence in the hostile host habitat and to its pathogenicity. The most extensively studied are cytotoxin-associated gene A (CagA) and vacuolating cytotoxin A (VacA). VacA is present in almost all H. pylori strains. As a secreted multifunctional toxin, it assists bacterial colonization, survival, and proliferation during long-lasting infections. To exert its effect on gastric epithelium and other cell types, VacA undergoes several modifications and crosses multiple membrane barriers. Once inside the gastric epithelial cell, VacA disrupts many cellular-signaling pathways and processes, leading mainly to changes in the efflux of various ions, the depolarization of membrane potential, and perturbations in endocytic trafficking and mitochondrial function. The most notable effect of VacA is the formation of vacuole-like structures, which may lead to apoptosis. This review focuses on the processes involved in VacA secretion, processing, and entry into host cells, with a particular emphasis on the interaction of the mature toxin with host membranes and the formation of transmembrane pores.
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Affiliation(s)
| | - Joanna Skorko-Glonek
- Department of General and Medical Biochemistry, Faculty of Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland;
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Jung MS, Piazuelo MB, Brackman LC, McClain MS, Algood HMS. Essential role of Helicobacter pylori apolipoprotein N-acyltransferase (Lnt) in stomach colonization. Infect Immun 2023; 91:e0036923. [PMID: 37937999 PMCID: PMC10715074 DOI: 10.1128/iai.00369-23] [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: 09/09/2023] [Accepted: 10/17/2023] [Indexed: 11/09/2023] Open
Abstract
Bacterial lipoproteins are post-translationally modified with acyl chains, anchoring these proteins to bacterial membranes. In Gram-negative bacteria, three enzymes complete the modifications. Lgt (which adds two acyl chains) and LspA (which removes the signal peptide) are essential. Lnt (which adds a third acyl chain) is not essential in certain bacteria including Francisella tularensis, Neisseria gonorrhoeae, and Acinetobacter baumannii. Deleting lnt results in mild to severe physiologic changes. We previously showed lnt is not essential for Helicobacter pylori growth in vitro. Here, the physiologic consequences of deleting lnt in H. pylori and the role of Lnt in the host response to H. pylori were examined using in vitro and in vivo models. Comparing wild-type, Δlnt, and complemented mutant H. pylori, no changes in growth rates or sensitivity to acid or antibiotics were observed. Since deleting lnt changes the number of acyl chains on lipoproteins and the number of acyl chains on lipoproteins impacts the innate immune response through Toll-like receptor 2 (TLR2) signaling, primary human gastric epithelial cells were treated with a purified lipoprotein from wild-type or lnt mutant H. pylori. Differential gene expression analysis indicated that lipoprotein from the lnt mutant induced a more robust TLR2 response. In a complementary approach, we infected wild-type and Tlr2-/- mice and found that both the wild-type and complemented mutant strains successfully colonized the animals. However, the lnt mutant strain was unable to colonize either mouse strain. These results show that lnt is essential for H. pylori colonization and identifies lipoprotein synthesis as a target for therapeutic intervention.
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Affiliation(s)
- Matthew S. Jung
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - M. Blanca Piazuelo
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Lee C. Brackman
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - 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
| | - 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
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5
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Dai C, Guo X, Pan Z, Wan C, Yang D, Li Y, Lian C, An Y, Zhang T, Yang F, Zhu L, Yin F, Wang R, Li Z. Pyridinium-Based Strategy for a Bioorthogonal Conjugation-Assisted Purification Method for Profiling Cell Surface Proteome. Anal Chem 2023; 95:17125-17134. [PMID: 37934015 DOI: 10.1021/acs.analchem.3c04279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
Abstract
Cell surface proteins (CSPs) are valuable targets for therapeutic agents, but achieving highly selective CSP enrichment in cellular physiology remains a technical challenge. To address this challenge, we propose a newly developed sulfo-pyridinium ester (SPE) cross-linking probe, followed by two-step imaging and enrichment. The SPE probe showed higher efficiency in labeling proteins than similar NHS esters at the level of cell lysates and demonstrated specificity for Lys in competitive experiments. More importantly, this probe could selectively label the cell membranes in cell imaging with only negligible labeling of the intracellular compartment. Moreover, we successfully performed this strategy on MCF-7 live cells to label 425 unique CSPs from 1162 labeled proteins. Finally, we employed our probe to label the CSPs of insulin-cultured MCF-7, revealing several cell surface targets of key functional biomarkers and insulin-associated pathogenesis. The above results demonstrate that the SPE method provides a promising tool for the selective labeling of cell surface proteins and monitoring transient cell surface events.
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Affiliation(s)
- Chuan Dai
- Pingshan Translational Medicine Center, Shenzhen Bay Laboratory, Shenzhen 518118, P. R. China
- State Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, P. R. China
- Department of Pharmacy, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital (Shenzhen Institute of Translational Medicine), Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, School of Biomedical Engineering, Shenzhen University Medical School, Shenzhen 518060, P. R. China
| | - Xiaochun Guo
- State Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, P. R. China
| | - Zhuoheng Pan
- School of Pharmacy, Macau University of Science and Technology, Taipa 999078, Macau, P. R. China
| | - Chuan Wan
- Pingshan Translational Medicine Center, Shenzhen Bay Laboratory, Shenzhen 518118, P. R. China
- State Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, P. R. China
| | - Dongyan Yang
- Pingshan Translational Medicine Center, Shenzhen Bay Laboratory, Shenzhen 518118, P. R. China
- State Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, P. R. China
| | - Yongli Li
- China Medical System Holdings Limited, Shenzhen 518055, P. R. China
| | - Chenshan Lian
- Pingshan Translational Medicine Center, Shenzhen Bay Laboratory, Shenzhen 518118, P. R. China
- State Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, P. R. China
| | - Yuhao An
- Pingshan Translational Medicine Center, Shenzhen Bay Laboratory, Shenzhen 518118, P. R. China
| | - Tuanjie Zhang
- Pingshan Translational Medicine Center, Shenzhen Bay Laboratory, Shenzhen 518118, P. R. China
| | - Fadeng Yang
- State Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, P. R. China
| | - Lizhi Zhu
- Department of Pharmacy, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People's Hospital (Shenzhen Institute of Translational Medicine), Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, National-Regional Key Technology Engineering Laboratory for Medical Ultrasound, School of Biomedical Engineering, Shenzhen University Medical School, Shenzhen 518060, P. R. China
| | - Feng Yin
- Pingshan Translational Medicine Center, Shenzhen Bay Laboratory, Shenzhen 518118, P. R. China
- State Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, P. R. China
| | - Rui Wang
- Pingshan Translational Medicine Center, Shenzhen Bay Laboratory, Shenzhen 518118, P. R. China
| | - Zigang Li
- Pingshan Translational Medicine Center, Shenzhen Bay Laboratory, Shenzhen 518118, P. R. China
- State Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, P. R. China
- Frontiers Medical Center, Tianfu Jincheng Laboratory, Chengdu 610212, Sichuan, P. R. China
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Rosli NA, Al-Maleki AR, Loke MF, Chua EG, Alhoot MA, Vadivelu J. Polymorphism of virulence genes and biofilm associated with in vitro induced resistance to clarithromycin in Helicobacter pylori. Gut Pathog 2023; 15:52. [PMID: 37898785 PMCID: PMC10613384 DOI: 10.1186/s13099-023-00579-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 10/19/2023] [Indexed: 10/30/2023] Open
Abstract
BACKGROUND Clarithromycin-containing triple therapy is commonly used to treat Helicobacter pylori infections. Clarithromycin resistance is the leading cause of H. pylori treatment failure. Understanding the specific mutations that occur in H. pylori strains that have evolved antibiotic resistance can help create a more effective and individualised antibiotic treatment plan. However, little is understood about the genetic reprogramming linked to clarithromycin exposure and the emergence of antibiotic resistance in H. pylori. Therefore, this study aims to identify compensatory mutations and biofilm formation associated with the development of clarithromycin resistance in H. pylori. Clarithromycin-sensitive H. pylori clinical isolates were induced to develop clarithromycin resistance through in vitro exposure to incrementally increasing concentration of the antibiotic. The genomes of the origin sensitive isolates (S), isogenic breakpoint (B), and resistant isolates (R) were sequenced. Single nucleotide variations (SNVs), and insertions or deletions (InDels) associated with the development of clarithromycin resistance were identified. Growth and biofilm production were also assessed. RESULTS The S isolates with A2143G mutation in the 23S rRNA gene were successfully induced to be resistant. According to the data, antibiotic exposure may alter the expression of certain genes, including those that code for the Cag4/Cag protein, the vacuolating cytotoxin domain-containing protein, the sel1 repeat family protein, and the rsmh gene, which may increase the risk of developing and enhances virulence in H. pylori. Enhanced biofilm formation was detected among R isolates compared to B and S isolates. Furthermore, high polymorphism was also detected among the genes associated with biofilm production. CONCLUSIONS Therefore, this study suggests that H. pylori may acquire virulence factors while also developing antibiotic resistance due to clarithromycin exposure.
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Affiliation(s)
- Naim Asyraf Rosli
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Anis Rageh Al-Maleki
- Department of Medical Microbiology, Faculty of Medicine, Universiti Malaya, 50603, Kuala Lumpur, Malaysia.
- Department of Medical Microbiology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen.
| | - Mun Fai Loke
- Camtech Biomedical Pte Ltd, Singapore, Singapore
| | - Eng Guan Chua
- School of Biomedical Sciences, Marshall Centre for Infectious Disease Research and Training, University of Western Australia, Perth, WA, Australia
| | - Mohammed Abdelfatah Alhoot
- Faculty of Pharmacy, Airlangga University, Surabaya, 60155, Indonesia
- School of Graduate Studies, Management & Science University, Shah Alam, Selangor, Malaysia
| | - Jamuna Vadivelu
- Medical Education Research and Development Unit, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
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7
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Li Z, Zhang Y, Mi C, Deng X, Wang X, Hu D, Yin K, Yin C, Zhao L, Shan B. Identification of the immunogenic membrane proteins, catalase, PgbA, and PgbB, as potential antigens against Helicobacter pylori. J Appl Microbiol 2023; 134:lxad218. [PMID: 37777837 DOI: 10.1093/jambio/lxad218] [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: 08/20/2022] [Revised: 08/24/2023] [Accepted: 09/29/2023] [Indexed: 10/02/2023]
Abstract
AIMS This study aims to investigate the specific membrane antigens that are targeted by antibodies raised against Helicobacter pylori. METHODS AND RESULTS Bovine milk antibodies were prepared using whole H. pylori, purified membrane proteins, or both. Enzyme-linked immunosorbent assay and sodium dodecyl sulfate-polyacrylamide gel electrophoresis experiments revealed that these immunogens triggered anti-H. pylori antibody production in milk. The highest antibody titer was induced by the mixture of whole bacteria and purified membrane proteins. The antibodies induced by mixed immunogens significantly inhibited H. pylori growth in vitro and were used to identify catalase, plasminogen-binding protein A (PgbA), and PgbB via western blotting, immunoprecipitation, and two-dimensional western blotting followed by liquid chromatography with tandem mass spectrophotometry. The immunogenicity of PgbA and PgbB was verified in mice vaccinated with their B-cell epitope vaccines. Following prophylactic vaccination of C57BL/6 mice, each of the three antigens alone and their combination reduced the weight loss in mice, increased antibody titers, and relieved the inflammatory status of the gastric mucosa following H. pylori infection. CONCLUSIONS Catalase, PgbA, and PgbB could serve as valuable membrane antigens for the development of anti-H. pylori immunotherapies.
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Affiliation(s)
- Zhirong Li
- Research Center, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, China
- Provincial Center for Clinical Laboratories, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei 050000, China
| | - Ying Zhang
- Research Center, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, China
| | - Chaoyi Mi
- Research Center, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, China
| | - Xiaoqing Deng
- Research Center, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, China
| | - Xian Wang
- Shijiazhuang Center for Disease Control and Prevention, Shijiazhuang, Hebei 050000, China
| | - Dailun Hu
- Clinical College, Hebei Medical University, Shijiazhuang, Hebei 050020, China
| | - Kaige Yin
- Department of Gastroenterology, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei 050000, China
| | - Changfu Yin
- Clinical College, Hebei Medical University, Shijiazhuang, Hebei 050020, China
| | - Lianmei Zhao
- Research Center, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, China
| | - Baoen Shan
- Research Center, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, China
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8
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Palacios E, Lobos-González L, Guerrero S, Kogan MJ, Shao B, Heinecke JW, Quest AFG, Leyton L, Valenzuela-Valderrama M. Helicobacter pylori outer membrane vesicles induce astrocyte reactivity through nuclear factor-κappa B activation and cause neuronal damage in vivo in a murine model. J Neuroinflammation 2023; 20:66. [PMID: 36895046 PMCID: PMC9996972 DOI: 10.1186/s12974-023-02728-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 02/10/2023] [Indexed: 03/11/2023] Open
Abstract
BACKGROUND Helicobacter pylori (Hp) infects the stomach of 50% of the world's population. Importantly, chronic infection by this bacterium correlates with the appearance of several extra-gastric pathologies, including neurodegenerative diseases. In such conditions, brain astrocytes become reactive and neurotoxic. However, it is still unclear whether this highly prevalent bacterium or the nanosized outer membrane vesicles (OMVs) they produce, can reach the brain, thus affecting neurons/astrocytes. Here, we evaluated the effects of Hp OMVs on astrocytes and neurons in vivo and in vitro. METHODS Purified OMVs were characterized by mass spectrometry (MS/MS). Labeled OMVs were administered orally or injected into the mouse tail vein to study OMV-brain distribution. By immunofluorescence of tissue samples, we evaluated: GFAP (astrocytes), βIII tubulin (neurons), and urease (OMVs). The in vitro effect of OMVs in astrocytes was assessed by monitoring NF-κB activation, expression of reactivity markers, cytokines in astrocyte-conditioned medium (ACM), and neuronal cell viability. RESULTS Urease and GroEL were prominent proteins in OMVs. Urease (OMVs) was present in the mouse brain and its detection coincided with astrocyte reactivity and neuronal damage. In vitro, OMVs induced astrocyte reactivity by increasing the intermediate filament proteins GFAP and vimentin, the plasma membrane αVβ3 integrin, and the hemichannel connexin 43. OMVs also produced neurotoxic factors and promoted the release of IFNγ in a manner dependent on the activation of the transcription factor NF-κB. Surface antigens on reactive astrocytes, as well as secreted factors in response to OMVs, were shown to inhibit neurite outgrowth and damage neurons. CONCLUSIONS OMVs administered orally or injected into the mouse bloodstream reach the brain, altering astrocyte function and promoting neuronal damage in vivo. The effects of OMVs on astrocytes were confirmed in vitro and shown to be NF-κB-dependent. These findings suggest that Hp could trigger systemic effects by releasing nanosized vesicles that cross epithelial barriers and access the CNS, thus altering brain cells.
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Affiliation(s)
- Esteban Palacios
- Laboratorio de Microbiología Celular, Instituto de Investigación y Postgrado, Facultad de Ciencias de La Salud, Universidad Central de Chile, 8330546, Santiago, Chile.,Laboratory of Cellular Communication, Center for Studies On Exercise Metabolism and Cancer (CEMC), Institute of Biomedical Sciences (ICBM), Facultad de Medicina, Universidad de Chile, 8380453, Santiago, Chile.,Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, 8380494, Santiago, Chile
| | - Lorena Lobos-González
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, 8380494, Santiago, Chile.,Centro de Medicina Regenerativa, Facultad de Medicina, Universidad del Desarrollo-Clínica Alemana, 7590943, Santiago, Chile
| | - Simón Guerrero
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, 8380494, Santiago, Chile.,Departamento de Química Farmacológica y Toxicológica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, 8380494, Santiago, Chile.,Facultad de Medicina, Universidad de Atacama, 153601, Copiapó, Chile
| | - Marcelo J Kogan
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, 8380494, Santiago, Chile.,Departamento de Química Farmacológica y Toxicológica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, 8380494, Santiago, Chile
| | - Baohai Shao
- Division of Metabolism, Endocrinology and Nutrition, University of Washington, Seattle, WA, 98195-8055, USA
| | - Jay W Heinecke
- Division of Metabolism, Endocrinology and Nutrition, University of Washington, Seattle, WA, 98195-8055, USA
| | - Andrew F G Quest
- Laboratory of Cellular Communication, Center for Studies On Exercise Metabolism and Cancer (CEMC), Institute of Biomedical Sciences (ICBM), Facultad de Medicina, Universidad de Chile, 8380453, Santiago, Chile.,Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, 8380494, Santiago, Chile
| | - Lisette Leyton
- Laboratory of Cellular Communication, Center for Studies On Exercise Metabolism and Cancer (CEMC), Institute of Biomedical Sciences (ICBM), Facultad de Medicina, Universidad de Chile, 8380453, Santiago, Chile. .,Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, 8380494, Santiago, Chile.
| | - Manuel Valenzuela-Valderrama
- Laboratorio de Microbiología Celular, Instituto de Investigación y Postgrado, Facultad de Ciencias de La Salud, Universidad Central de Chile, 8330546, Santiago, Chile. .,Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, 8380494, Santiago, Chile.
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9
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Reyes VE. Helicobacter pylori Immune Response in Children Versus Adults. MEDICAL RESEARCH ARCHIVES 2022; 10:3370. [PMID: 37936946 PMCID: PMC10629867 DOI: 10.18103/mra.v10i12.3370] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/09/2023]
Abstract
H. pylori is perhaps the most prevalent human pathogen worldwide and infects almost half of the world's population. Despite the decreasing prevalence of infection overall, it is significant in developing countries. Most infections are acquired in childhood and persist for a lifetime unless treated. Children are often asymptomatic and often develop a tolerogenic immune response that includes T regulatory cells and their products, immunosuppressive cytokines, such as interleukin (IL)-10, and transforming growth factor-β (TGF-β). This contrasts to the gastric immune response seen in H. pylori-infected adults, where the response is mainly inflammatory, with predominant Th1 and Th17 cells, as well as, inflammatory cytokines, such as TNF-α, IFN-γ, IL-1, IL-6, IL-8, and IL-17. Therefore, compared to adults, infected children generally have limited gastric inflammation and peptic ulcer disease. H. pylori surreptitiously subverts immune defenses to persist in the human gastric mucosa for decades. The chronic infection might result in clinically significant diseases in adults, such as peptic ulcer disease, gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma. This review compares the infection in children and adults and highlights the H. pylori virulence mechanisms responsible for the pathogenesis and immune evasion.
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Affiliation(s)
- Victor E. Reyes
- Department of Pediatrics, Department of Microbiology and Immunology, University of Texas Medical Branch, 301 University Blvd. Galveston, TX 77555-0372 USA
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10
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Delineation of the pH-Responsive Regulon Controlled by the Helicobacter pylori ArsRS Two-Component System. Infect Immun 2021; 89:IAI.00597-20. [PMID: 33526561 DOI: 10.1128/iai.00597-20] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 01/09/2021] [Indexed: 12/22/2022] Open
Abstract
Helicobacter pylori encounters a wide range of pH within the human stomach. In a comparison of H. pylori cultured in vitro under neutral or acidic conditions, about 15% of genes are differentially expressed, and corresponding changes are detectable for many of the encoded proteins. The ArsRS two-component system (TCS), comprised of the sensor kinase ArsS and its cognate response regulator ArsR, has an important role in mediating pH-responsive changes in H. pylori gene expression. In this study, we sought to delineate the pH-responsive ArsRS regulon and further define the role of ArsR in pH-responsive gene expression. We compared H. pylori strains containing an intact ArsRS system with an arsS null mutant or strains containing site-specific mutations of a conserved aspartate residue (D52) in ArsR, which is phosphorylated in response to signals relayed by the cognate sensor kinase ArsS. We identified 178 genes that were pH-responsive in strains containing an intact ArsRS system but not in ΔarsS or arsR mutants. These constituents of the pH-responsive ArsRS regulon include genes involved in acid acclimatization (ureAB, amidases), oxidative stress responses (katA, sodB), transcriptional regulation related to iron or nickel homeostasis (fur, nikR), and genes encoding outer membrane proteins (including sabA, alpA, alpB, hopD [labA], and horA). When comparing H. pylori strains containing an intact ArsRS TCS with arsRS mutants, each cultured at neutral pH, relatively few genes are differentially expressed. Collectively, these data suggest that ArsRS-mediated gene regulation has an important role in H. pylori adaptation to changing pH conditions.
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Soyfoo DM, Doomah YH, Xu D, Zhang C, Sang HM, Liu YY, Zhang GX, Jiang JX, Xu SF. New genotypes of Helicobacter Pylori VacA d-region identified from global strains. BMC Mol Cell Biol 2021; 22:4. [PMID: 33413074 PMCID: PMC7791883 DOI: 10.1186/s12860-020-00338-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 12/16/2020] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Pathogenesis of Helicobacter Pylori (HP) vacuolating toxin A (vacA) depends on polymorphic diversity within the signal (s), middle (m), intermediate (i), deletion (d) and c-regions. These regions show distinct allelic diversity. The s-region, m-region and the c-region (a 15 bp deletion at the 3'-end region of the p55 domain of the vacA gene) exist as 2 types (s1, s2, m1, m2, c1 and c2), while the i-region has 3 allelic types (i1, i2 and i3). The locus of d-region of the vacA gene has also been classified into 2 genotypes, namely d1 and d2. We investigated the "d-region"/"loop region" through bioinformatics, to predict its properties and relation to disease. One thousand two hundred fifty-nine strains from the NCBI nucleotide database and the dryad database with complete vacA sequences were included in the study. The sequences were aligned using BioEdit and analyzed using Lasergene and BLAST. The secondary structure and physicochemical properties of the region were predicted using PredictProtein. RESULTS We identified 31 highly polymorphic genotypes in the "d-region", with a mean length of 34 amino acids (9 ~ 55 amino acids). We further classified the 31 genotypes into 3 main types, namely K-type (strains starting with the KDKP motif in the "d-region"), Q-type (strains starting with the KNQT motif), and E-type (strains starting with the ESKT motif) respectively. The most common type, K-type, is more prevalent in cancer patients (80.87%) and is associated with the s1i1m1c1 genotypes (P < .01). Incidentally, a new region expressing sequence diversity (2 aa deletion) at the C-terminus of the p55 domain of vacA was identified during bioinformatics analysis. CONCLUSIONS Prediction of secondary structures shows that the "d-region" adopts a loop conformation and is a disordered region.
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Affiliation(s)
- Djaleel Muhammad Soyfoo
- Department of Gastroenterology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Yussriya Hanaa Doomah
- Department of Obstetrics and Gynecology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Dong Xu
- Department of Electrical Engineering and Computer Science, Bond Life Sciences Center, University of Missouri, Columbia, MO, USA
| | - Chao Zhang
- Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, 10021, USA.,Division of Hematology and Medical Oncology, Department of Medicine, Weill Cornell Medicine, New York, NY, 10021, USA
| | - Huai-Ming Sang
- Department of Gastroenterology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Yan-Yan Liu
- Department of Gastroenterology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Guo-Xin Zhang
- Department of Gastroenterology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Jian-Xia Jiang
- Department of Gastroenterology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
| | - Shun-Fu Xu
- Department of Gastroenterology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
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Varga MG, Wood CR, Butt J, Ryan ME, You WC, Pan K, Waterboer T, Epplein M, Shaffer CL. Immunostimulatory membrane proteins potentiate H. pylori-induced carcinogenesis by enabling CagA translocation. Gut Microbes 2021; 13:1-13. [PMID: 33382363 PMCID: PMC7781638 DOI: 10.1080/19490976.2020.1862613] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 11/04/2020] [Accepted: 11/26/2020] [Indexed: 02/07/2023] Open
Abstract
Infection with Helicobacter pylori is the single greatest risk factor for developing gastric adenocarcinoma. In prospective, population-based studies, seropositivity to the uncharacterized H. pylori proteins Hp0305 and Hp1564 was significantly associated with cancer risk in East Asia. However, the mechanism underlying this observation has not been elucidated. Here, we show that Hp0305 and Hp1564 act in concert with previously ascribed H. pylori virulence mechanisms to orchestrate cellular alterations that promote gastric carcinogenesis. In samples from 546 patients exhibiting premalignant gastric lesions, seropositivity to Hp0305 and Hp1564 was significantly associated with increased gastric atrophy across all stomach conditions. In vitro, depletion of Hp0305 and Hp1564 significantly reduced levels of gastric cell-associated bacteria and markedly impaired the ability of H. pylori to stimulate pro-inflammatory cytokine production. Remarkably, our studies revealed that Hp1564 is required for translocation of the oncoprotein CagA into gastric epithelial cells. Our data provide experimental insight into the molecular mechanisms governing novel H. pylori pathogenicity factors that are strongly associated with gastric disease and highlight the potential of Hp0305 and Hp1564 as robust molecular tools that can improve identification of individuals that are highly susceptible to gastric cancer. We demonstrate that Hp0305 and Hp1564 augment H. pylori-mediated inflammation and gastric cancer risk by promoting key bacteria-gastric cell interactions that facilitate delivery of oncogenic microbial cargo to target cells. Thus, therapeutically targeting microbial interactions driven by Hp0305/Hp1564 may enable focused H. pylori eradication strategies to prevent development of gastric malignancies in high-risk populations.
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Affiliation(s)
- Matthew G. Varga
- Department of Epidemiology, Lineberger Comprehensive Cancer Center and Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, USA
| | - Cecily R. Wood
- Department of Veterinary Science, University of Kentucky, Lexington, KY, USA
| | - Julia Butt
- Infections and Cancer Epidemiology, German Cancer Research Center, Heidelberg, Germany
| | - Mackenzie E. Ryan
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington, KY, USA
| | - Wei-Cheng You
- Department of Cancer Epidemiology, Peking University Cancer Hospital and Institute, Beijing, China
| | - Kaifeng Pan
- Department of Cancer Epidemiology, Peking University Cancer Hospital and Institute, Beijing, China
| | - Tim Waterboer
- Infections and Cancer Epidemiology, German Cancer Research Center, Heidelberg, Germany
| | - Meira Epplein
- Department of Population Health Sciences and Duke Cancer Institute, Cancer Control and Population Sciences Program, Duke University, Durham, NC, USA
| | - Carrie L. Shaffer
- Department of Veterinary Science, University of Kentucky, Lexington, KY, USA
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington, KY, USA
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY, USA
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Mwangi C, Njoroge S, Tshibangu-Kabamba E, Moloo Z, Rajula A, Devani S, Matsumoto T, Nyerere K, Kariuki S, Revathi G, Yamaoka Y. Whole Genome Sequencing Reveals Virulence Potentials of Helicobacter pylori Strain KE21 Isolated from a Kenyan Patient with Gastric Signet Ring Cell Carcinoma. Toxins (Basel) 2020; 12:E556. [PMID: 32872465 PMCID: PMC7551074 DOI: 10.3390/toxins12090556] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 08/26/2020] [Accepted: 08/27/2020] [Indexed: 12/24/2022] Open
Abstract
Helicobacter pylori (H.pylori) infection is etiologically associated with severe diseases including gastric cancer; but its pathogenicity is deeply shaped by the exceptional genomic diversification and geographic variation of the species. The clinical relevance of strains colonizing Africa is still debated. This study aimed to explore genomic features and virulence potentials of H. pylori KE21, a typical African strain isolated from a native Kenyan patient diagnosed with a gastric cancer. A high-quality circular genome assembly of 1,648,327 bp (1590 genes) obtained as a hybrid of Illumina Miseq short reads and Oxford Nanopore MinION long reads, clustered within hpAfrica1 population. This genome revealed a virulome and a mobilome encoding more than hundred features potentiating a successful colonization, persistent infection, and enhanced disease pathogenesis. Furthermore, through an experimental infection of gastric epithelial cell lines, strain KE21 showed the ability to promote interleukin-8 production and to induce cellular alterations resulting from the injection of a functional CagA oncogene protein into the cells. This study shows that strain KE21 is potentially virulent and can trigger oncogenic pathways in gastric epithelial cells. Expended genomic and clinical explorations are required to evaluate the epidemiological importance of H. pylori infection and its putative complications in the study population.
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Affiliation(s)
- Catherine Mwangi
- Department of Medical Microbiology, Jomo Kenyatta University of Agriculture and Technology, Nairobi P.O. Box 62000-00200, Kenya; (C.M.); (S.N.); (K.N.)
- Department of Medical Microbiology and Parasitology, Kenyatta University, Nairobi P.O. Box 43844-00100, Kenya
| | - Stephen Njoroge
- Department of Medical Microbiology, Jomo Kenyatta University of Agriculture and Technology, Nairobi P.O. Box 62000-00200, Kenya; (C.M.); (S.N.); (K.N.)
- Department of Medical Microbiology, Technical University of Kenya, Nairobi P.O. Box 52428, Kenya
| | - Evariste Tshibangu-Kabamba
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Oita 879-5593, Japan; (E.T.-K.); (T.M.)
| | - Zahir Moloo
- Department of Pathology and Laboratory Medicine, Aga Khan Hospital University, Nairobi P.O. Box 37002-00100, Kenya; (Z.M.); (G.R.)
| | - Allan Rajula
- Gastroenterology section, Aga Khan Hospital University, Nairobi P.O. Box 37002-00100, Kenya; (A.R.); (S.D.)
| | - Smita Devani
- Gastroenterology section, Aga Khan Hospital University, Nairobi P.O. Box 37002-00100, Kenya; (A.R.); (S.D.)
| | - Takashi Matsumoto
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Oita 879-5593, Japan; (E.T.-K.); (T.M.)
| | - Kimang’a Nyerere
- Department of Medical Microbiology, Jomo Kenyatta University of Agriculture and Technology, Nairobi P.O. Box 62000-00200, Kenya; (C.M.); (S.N.); (K.N.)
| | - Samuel Kariuki
- Kenya Medical Research Institute, Nairobi P.O. Box 20778-00202, Kenya;
| | - Gunturu Revathi
- Department of Pathology and Laboratory Medicine, Aga Khan Hospital University, Nairobi P.O. Box 37002-00100, Kenya; (Z.M.); (G.R.)
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Oita 879-5593, Japan; (E.T.-K.); (T.M.)
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14
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Soluri MF, Puccio S, Caredda G, Edomi P, D’Elios MM, Cianchi F, Troilo A, Santoro C, Sblattero D, Peano C. Defining the Helicobacter pylori Disease-Specific Antigenic Repertoire. Front Microbiol 2020; 11:1551. [PMID: 32849324 PMCID: PMC7396715 DOI: 10.3389/fmicb.2020.01551] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 06/16/2020] [Indexed: 12/19/2022] Open
Abstract
The analysis of the interaction between Helicobacter pylori (HP) and the host in vivo is an extremely informative way to enlighten the molecular mechanisms behind the persistency/latency of the bacterium as well as in the progression of the infection. An important source of information is represented by circulating antibodies targeting the bacteria that define a specific "disease signature" with prospective diagnostic implications. The diagnosis of some of the HP induced diseases such as gastric cancer (GC), MALT lymphoma (MALT), and autoimmune gastritis (AIG) is not easy because patients do not show symptoms of illness in early-onset stages, at the same time they progress rapidly. The possibility of identifying markers able to provide an early diagnosis would be extremely beneficial since a late diagnosis results in a delay in undergoing active therapy and reduces the survival rate of patients. With the aim to identify the HP antigens recognized during the host immune-response to the infection and possibly disease progression, we applied a discovery-driven approach, that combines "phage display" and deep sequencing. The procedure is based on the selection of ORF phage libraries, specifically generated from the pathogen's genome, with sera antibodies from patients with different HP-related diseases. To this end two phage display libraries have been constructed starting from genomic DNA from the reference HP 26695 and the pathogenic HP B128 strains; libraries were filtered for ORFs by using an ORF selection vector developed by our group (Di Niro et al., 2005; Soluri et al., 2018), selected with antibodies from patients affected by GC, MALT, and AIG and putative HP antigens/epitopes were identified after Sequencing and ranking. The results show that individual selection significantly reduced the library diversity and comparison of individual ranks for each condition allowed us to highlight a pattern of putative antigens specific for the different pathological outcomes or common for all of them. Within the putative antigens enriched after selection, we have validated protein CagY/Cag7 by ELISA assay as a marker of HP infection and progression. Overall, we have defined HP antigenic repertoire and identified a panel of putative specific antigens/epitopes for three different HP infection pathological outcomes that could be validated in the next future.
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Affiliation(s)
- Maria Felicia Soluri
- Department of Health Sciences & IRCAD, Università del Piemonte Orientale, Novara, Italy
- Center for Translational Research on Autoimmune and Allergic Disease, Università del Piemonte Orientale, Novara, Italy
| | - Simone Puccio
- Laboratory of Translational Immunology, IRCCS, Humanitas Clinical and Research Center, Rozzano, Italy
| | - Giada Caredda
- Department of Excellence in Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Paolo Edomi
- Department of Life Sciences, University of Trieste, Trieste, Italy
| | - Mario Milco D’Elios
- Department of Experimental and Clinical Medicine, School of Human Health Sciences, University of Florence, Florence, Italy
| | - Fabio Cianchi
- Department of Experimental and Clinical Medicine, School of Human Health Sciences, University of Florence, Florence, Italy
| | - Arianna Troilo
- Department of Experimental and Clinical Medicine, School of Human Health Sciences, University of Florence, Florence, Italy
| | - Claudio Santoro
- Department of Health Sciences & IRCAD, Università del Piemonte Orientale, Novara, Italy
- Center for Translational Research on Autoimmune and Allergic Disease, Università del Piemonte Orientale, Novara, Italy
| | | | - Clelia Peano
- Institute of Genetic and Biomedical Research, UoS Milan, National Research Council, Milan, Italy
- Genomic Unit, IRCCS, Humanitas Clinical and Research Center, Milan, Italy
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15
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Hathroubi S, Zerebinski J, Clarke A, Ottemann KM. Helicobacter pylori Biofilm Confers Antibiotic Tolerance in Part via A Protein-Dependent Mechanism. Antibiotics (Basel) 2020; 9:E355. [PMID: 32599828 PMCID: PMC7345196 DOI: 10.3390/antibiotics9060355] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 06/16/2020] [Accepted: 06/22/2020] [Indexed: 12/20/2022] Open
Abstract
Helicobacter pylori, a WHO class I carcinogen, is one of the most successful human pathogens colonizing the stomach of over 4.4 billion of the world's population. Antibiotic therapy represents the best solution but poor response rates have hampered the elimination of H. pylori. A growing body of evidence suggests that H. pylori forms biofilms, but the role of this growth mode in infection remains elusive. Here, we demonstrate that H. pylori cells within a biofilm are tolerant to multiple antibiotics in a manner that depends partially on extracellular proteins. Biofilm-forming cells were tolerant to multiple antibiotics that target distinct pathways, including amoxicillin, clarithromycin, and tetracycline. Furthermore, this tolerance was significantly dampened following proteinase K treatment. These data suggest that H. pylori adapts its phenotype during biofilm growth resulting in decreased antibiotic susceptibility but this tolerance can be partially ameliorated by extracellular protease treatment.
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Affiliation(s)
- Skander Hathroubi
- Department of Microbiology and Environmental Toxicology, University of California, Santa Cruz, CA 95064, USA
- Institüt für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, 10115 Berlin, Germany; (J.Z.); (A.C.)
| | - Julia Zerebinski
- Institüt für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, 10115 Berlin, Germany; (J.Z.); (A.C.)
| | - Aaron Clarke
- Institüt für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, 10115 Berlin, Germany; (J.Z.); (A.C.)
| | - Karen M. Ottemann
- Institüt für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, 10115 Berlin, Germany; (J.Z.); (A.C.)
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16
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Su YC, Mattsson E, Singh B, Jalalvand F, Murphy TF, Riesbeck K. The Laminin Interactome: A Multifactorial Laminin-Binding Strategy by Nontypeable Haemophilus influenzae for Effective Adherence and Colonization. J Infect Dis 2020; 220:1049-1060. [PMID: 31034569 DOI: 10.1093/infdis/jiz217] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Accepted: 04/26/2019] [Indexed: 12/13/2022] Open
Abstract
Laminin is a well-defined component of the airway basement membrane (BM). Efficient binding of laminin via multiple interactions is important for nontypeable Haemophilus influenzae (NTHi) colonization in the airway mucosa. In this study, we identified elongation factor thermo-unstable (EF-Tu), l-lactate dehydrogenase (LDH), protein D (PD), and peptidoglycan-associated lipoprotein P6 as novel laminin-binding proteins (Lbps) of NTHi. In parallel with other well-studied Lbps (protein 4 [P4], protein E [PE], protein F [PF], and Haemophilus adhesion and penetration protein [Hap]), EF-Tu, LDH, PD, and P6 exhibited interactions with laminin, and mediated NTHi laminin-dependent adherence to pulmonary epithelial cell lines. More importantly, the NTHi laminin interactome consisting of the well-studied and novel Lbps recognized laminin LG domains from the subunit α chains of laminin-111 and -332, the latter isoform of which is the main laminin in the airway BM. The NTHi interactome mainly targeted multiple heparin-binding domains of laminin. In conclusion, the NTHi interactome exhibited a high plasticity of interactions with different laminin isoforms via multiple heparin-binding sites.
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Affiliation(s)
- Yu-Ching Su
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Emma Mattsson
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Birendra Singh
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Farshid Jalalvand
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Timothy F Murphy
- Clinical and Translational Research Center, University at Buffalo, the State University of New York
| | - Kristian Riesbeck
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
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17
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Chu J, Liu J, Hoover TR. Phylogenetic Distribution, Ultrastructure, and Function of Bacterial Flagellar Sheaths. Biomolecules 2020; 10:biom10030363. [PMID: 32120823 PMCID: PMC7175336 DOI: 10.3390/biom10030363] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 02/25/2020] [Accepted: 02/26/2020] [Indexed: 02/06/2023] Open
Abstract
A number of Gram-negative bacteria have a membrane surrounding their flagella, referred to as the flagellar sheath, which is continuous with the outer membrane. The flagellar sheath was initially described in Vibrio metschnikovii in the early 1950s as an extension of the outer cell wall layer that completely surrounded the flagellar filament. Subsequent studies identified other bacteria that possess flagellar sheaths, most of which are restricted to a few genera of the phylum Proteobacteria. Biochemical analysis of the flagellar sheaths from a few bacterial species revealed the presence of lipopolysaccharide, phospholipids, and outer membrane proteins in the sheath. Some proteins localize preferentially to the flagellar sheath, indicating mechanisms exist for protein partitioning to the sheath. Recent cryo-electron tomography studies have yielded high resolution images of the flagellar sheath and other structures closely associated with the sheath, which has generated insights and new hypotheses for how the flagellar sheath is synthesized. Various functions have been proposed for the flagellar sheath, including preventing disassociation of the flagellin subunits in the presence of gastric acid, avoiding activation of the host innate immune response by flagellin, activating the host immune response, adherence to host cells, and protecting the bacterium from bacteriophages.
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Affiliation(s)
- Joshua Chu
- Department of Microbiology, Cornell University, Ithaca, NY 14853, USA;
| | - Jun Liu
- Microbial Sciences Institute, Department of Microbial Pathogenesis, Yale University, West Haven, CT 06516, USA;
| | - Timothy R. Hoover
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
- Correspondence: ; Tel.: +1-706-542-2675
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Saladi S, Boos F, Poglitsch M, Meyer H, Sommer F, Mühlhaus T, Schroda M, Schuldiner M, Madeo F, Herrmann JM. The NADH Dehydrogenase Nde1 Executes Cell Death after Integrating Signals from Metabolism and Proteostasis on the Mitochondrial Surface. Mol Cell 2020; 77:189-202.e6. [DOI: 10.1016/j.molcel.2019.09.027] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Revised: 08/16/2019] [Accepted: 09/23/2019] [Indexed: 12/22/2022]
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Li Y, Qin H, Ye M. An overview on enrichment methods for cell surface proteome profiling. J Sep Sci 2019; 43:292-312. [PMID: 31521063 DOI: 10.1002/jssc.201900700] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 09/09/2019] [Accepted: 09/11/2019] [Indexed: 12/17/2022]
Abstract
Cell surface proteins are essential for many important biological processes, including cell-cell interactions, signal transduction, and molecular transportation. With the characteristics of low abundance, high hydrophobicity, and high heterogeneity, it is difficult to get a comprehensive view of cell surface proteome by direct analysis. Thus, it is important to selectively enrich the cell surface proteins before liquid chromatography with mass spectrometry analysis. In recent years, a variety of enrichment methods have been developed. Based on the separation mechanism, these methods could be mainly classified into three types. The first type is based on their difference in the physicochemical property, such as size, density, charge, and hydrophobicity. The second one is based on the bimolecular affinity interaction with lectin or antibody. And the third type is based on the chemical covalent coupling to free side groups of surface-exposed proteins or carbohydrate chains, such as primary amines, carboxyl groups, glycan side chains. In addition, metabolic labeling and enzymatic reaction-based methods have also been employed to selectively isolate cell surface proteins. In this review, we will provide a comprehensive overview of the enrichment methods for cell surface proteome profiling.
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Affiliation(s)
- Yanan Li
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences (CAS), Dalian, 116023, P. R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P. R. China
| | - Hongqiang Qin
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences (CAS), Dalian, 116023, P. R. China
| | - Mingliang Ye
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences (CAS), Dalian, 116023, P. R. China
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Feroz H, Meisenhelter J, Jokhadze G, Bruening M, Kumar M. Rapid screening and scale‐up of ultracentrifugation‐free, membrane‐based procedures for purification of His‐tagged membrane proteins. Biotechnol Prog 2019; 35:e2859. [DOI: 10.1002/btpr.2859] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Revised: 04/13/2019] [Accepted: 05/03/2019] [Indexed: 12/28/2022]
Affiliation(s)
- Hasin Feroz
- Department of Chemical Engineering The Pennsylvania State University University Park Pennsylvania
| | - Joshua Meisenhelter
- Department of Chemical Engineering The Pennsylvania State University University Park Pennsylvania
| | | | - Merlin Bruening
- Department of Chemical and Biomolecular Engineering University of Notre Dame Notre Dame Indiana
| | - Manish Kumar
- Department of Chemical Engineering The Pennsylvania State University University Park Pennsylvania
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21
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Caston RR, Loh JT, Voss BJ, McDonald WH, Scholz MB, McClain MS, Cover TL. Effect of environmental salt concentration on the Helicobacter pylori exoproteome. J Proteomics 2019; 202:103374. [PMID: 31063819 DOI: 10.1016/j.jprot.2019.05.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 04/20/2019] [Accepted: 05/02/2019] [Indexed: 02/07/2023]
Abstract
Helicobacter pylori infection and a high salt diet are each risk factors for gastric cancer. In this study, we tested the hypothesis that environmental salt concentration influences the composition of the H. pylori exoproteome. H. pylori was cultured in media containing varying concentrations of sodium chloride, and aliquots were fractionated and analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). We identified proteins that were selectively released into the extracellular space, and we identified selectively released proteins that were differentially abundant in culture supernatants, depending on the environmental salt concentration. We also used RNA-seq analysis to identify genes that were differentially expressed in response to environmental salt concentration. The salt-responsive proteins identified by proteomic analysis and salt-responsive genes identified by RNA-seq analysis were mostly non-concordant, but the secreted toxin VacA was salt-responsive in both analyses. Western blot analysis confirmed that VacA levels in the culture supernatant were increased in response to high salt conditions, and quantitative RT-qPCR experiments confirmed that vacA transcription was upregulated in response to high salt conditions. These results indicate that environmental salt concentration influences the composition of the H. pylori exoproteome, which could contribute to the increased risk of gastric cancer associated with a high salt diet. SIGNIFICANCE: Helicobacter pylori-induced alterations in the gastric mucosa have been attributed, at least in part, to the actions of secreted H. pylori proteins. In this study, we show that H. pylori growth in high salt concentrations leads to increased levels of a secreted VacA toxin. Salt-induced alterations in the composition of the H. pylori exoproteome is relevant to the increased risk of gastric cancer associated with consumption of a high salt diet.
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Affiliation(s)
- Rhonda R Caston
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - John T Loh
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Bradley J Voss
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - W Hayes McDonald
- Proteomics Laboratory, Mass Spectrometry Research Center, Vanderbilt University School of Medicine, Nashville, TN, USA; Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Matthew B Scholz
- Vanderbilt Technologies for Advanced Genetics (VANTAGE), Vanderbilt University Medical Center, Nashville, TN, USA
| | - Mark S McClain
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Timothy L Cover
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, USA; Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA; Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN, USA.
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22
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Fagerquist CK, Zaragoza WJ. Proteolytic Surface-Shaving and Serotype-Dependent Expression of SPI-1 Invasion Proteins in Salmonella enterica Subspecies enterica. Front Nutr 2018; 5:124. [PMID: 30619870 PMCID: PMC6295468 DOI: 10.3389/fnut.2018.00124] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 11/23/2018] [Indexed: 12/15/2022] Open
Abstract
We performed proteolytic surface-shaving with trypsin on three strains/sevovars of Salmonella enterica enterica (SEE): Newport, Kentucky, and Thompson. Surfaced-exposed proteins of live bacterial cells were digested for 15 min. A separate 20 h re-digestion was also performed on the supernatant of each shaving experiment to more completely digest protein fragments into detectable peptides for proteomic analysis by nano-liquid chromatography-electrospray ionization-Orbitrap mass spectrometry. Control samples (i.e., no trypsin during surface-shaving step) were also performed in parallel. We detected peptides of flagella proteins: FliC (filament), FliD (cap), and FlgL (hook-filament junction) as well as peptides of FlgM (anti-σ28 factor), i.e., the negative regulator of flagella synthesis. For SEE Newport and Thompson, we detected Salmonella pathogenicity island 1 (SPI-1) secreted effector/invasion proteins: SipA, SipB, SipC, and SipD, whereas no Sip proteins were detected in control samples. No Sip proteins were detected for SEE Kentucky (or its control) although sip genes were confirmed to be present. Our results may suggest a biological response (<15 min) to proteolysis of live cells for these SEE strains and, in the case of Newport and Thompson, a possible invasion response.
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Affiliation(s)
- Clifton K Fagerquist
- Produce Safety & Microbiology Research Unit, Western Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, Albany, CA, United States
| | - William J Zaragoza
- Produce Safety & Microbiology Research Unit, Western Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, Albany, CA, United States
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23
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Mannion A, Shen Z, Fox JG. Comparative genomics analysis to differentiate metabolic and virulence gene potential in gastric versus enterohepatic Helicobacter species. BMC Genomics 2018; 19:830. [PMID: 30458713 PMCID: PMC6247508 DOI: 10.1186/s12864-018-5171-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 10/15/2018] [Indexed: 02/08/2023] Open
Abstract
Background The genus Helicobacter are gram-negative, microaerobic, flagellated, mucus-inhabiting bacteria associated with gastrointestinal inflammation and classified as gastric or enterohepatic Helicobacter species (EHS) according to host species and colonization niche. While there are over 30 official species, little is known about the physiology and pathogenic mechanisms of EHS, which account for most in the genus, as well as what genetic factors differentiate gastric versus EHS, given they inhabit different hosts and colonization niches. The objective of this study was to perform a whole-genus comparative analysis of over 100 gastric versus EHS genomes in order to identify genetic determinants that distinguish these Helicobacter species and provide insights about their evolution/adaptation to different hosts, colonization niches, and mechanisms of virulence. Results Whole-genome phylogeny organized Helicobacter species according to their presumed gastric or EHS classification. Analysis of orthologs revealed substantial heterogeneity in physiological and virulence-related genes between gastric and EHS genomes. Metabolic reconstruction predicted that unlike gastric species, EHS appear asaccharolytic and dependent on amino/organic acids to fuel metabolism. Additionally, gastric species lack de novo biosynthetic pathways for several amino acids and purines found in EHS and instead rely on environmental uptake/salvage pathways. Comparison of virulence factor genes between gastric and EHS genomes identified overlapping yet distinct profiles and included canonical cytotoxins, outer membrane proteins, secretion systems, and survival factors. Conclusions The major differences in predicted metabolic function suggest gastric species and EHS may have evolved for survival in the nutrient-rich stomach versus the nutrient-devoid environments, respectively. Contrasting virulence factor gene profiles indicate gastric species and EHS may utilize different pathogenic mechanisms to chronically infect hosts and cause inflammation and tissue damage. The findings from this study provide new insights into the genetic differences underlying gastric versus EHS and support the need for future experimental studies to characterize these pathogens. Electronic supplementary material The online version of this article (10.1186/s12864-018-5171-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Anthony Mannion
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA, USA.
| | - Zeli Shen
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - James G Fox
- Division of Comparative Medicine, Massachusetts Institute of Technology, Cambridge, MA, USA
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24
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Esbelin J, Santos T, Ribière C, Desvaux M, Viala D, Chambon C, Hébraud M. Comparison of three methods for cell surface proteome extraction of Listeria monocytogenes biofilms. OMICS-A JOURNAL OF INTEGRATIVE BIOLOGY 2018; 22:779-787. [PMID: 30457927 DOI: 10.1089/omi.2018.0144] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The cell surface proteome of the foodborne pathogen Listeria monocytogenes, the etiological agent of listeriosis, is critical for understanding the physiological processes associated with stress resistance and persistence in the environment. In this context, the most widespread mode of growth for bacterial cells in natural and industrial environments is in biofilms. Cell surface proteins are, however, challenging to characterize because of their low abundance and poor solubility. Moreover, cell surface protein extracts are usually contaminated with cytoplasmic proteins that constitute the main signal in proteomic analysis. This study aimed to compare the efficiency of three methods to extract and explore surface proteins of L. monocytogenes growing in a biofilm: trypsin shaving, biotinylation, and cell fractionation. Peptide separation and identification were performed by shotgun proteomics using high-performance liquid chromatography combined with tandem mass spectrometry (LC-MS/MS). The biotinylation method was the most effective in extracting surface proteins, with the lowest rate of contamination by cytoplasmic proteins. Although presenting a higher contamination rate in cytoplasmic proteins, the other two techniques allowed the identification of additional surface proteins. Seven proteins were commonly retrieved by the three methods. The extracted proteins belong to several functional classes, involved in virulence, transport, or metabolic pathways. Finally, the three extraction methods seemed complementary and their combined use improved the exploration of the bacterial surface proteome. These new findings collectively inform future discovery and translational proteomics for clinical, environmental health, and industrial applications.
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Affiliation(s)
- Julia Esbelin
- 1 Université Clermont Auvergne, INRA, UMR Microbiologie Environnement Digestif Santé (MEDiS), Saint-Genès Champanelle, France
| | - Tiago Santos
- 1 Université Clermont Auvergne, INRA, UMR Microbiologie Environnement Digestif Santé (MEDiS), Saint-Genès Champanelle, France
| | - Céline Ribière
- 1 Université Clermont Auvergne, INRA, UMR Microbiologie Environnement Digestif Santé (MEDiS), Saint-Genès Champanelle, France
| | - Mickaël Desvaux
- 1 Université Clermont Auvergne, INRA, UMR Microbiologie Environnement Digestif Santé (MEDiS), Saint-Genès Champanelle, France
| | - Didier Viala
- 2 INRA, Plate-Forme d'Exploration du Métabolisme composante protéomique (PFEMcp), Saint-Genès Champanelle, France
| | - Christophe Chambon
- 2 INRA, Plate-Forme d'Exploration du Métabolisme composante protéomique (PFEMcp), Saint-Genès Champanelle, France
| | - Michel Hébraud
- 1 Université Clermont Auvergne, INRA, UMR Microbiologie Environnement Digestif Santé (MEDiS), Saint-Genès Champanelle, France.,2 INRA, Plate-Forme d'Exploration du Métabolisme composante protéomique (PFEMcp), Saint-Genès Champanelle, France
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25
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Lekmeechai S, Su YC, Brant M, Alvarado-Kristensson M, Vallström A, Obi I, Arnqvist A, Riesbeck K. Helicobacter pylori Outer Membrane Vesicles Protect the Pathogen From Reactive Oxygen Species of the Respiratory Burst. Front Microbiol 2018; 9:1837. [PMID: 30245670 PMCID: PMC6137165 DOI: 10.3389/fmicb.2018.01837] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 07/23/2018] [Indexed: 01/28/2023] Open
Abstract
Outer membrane vesicles (OMVs) play an important role in the persistence of Helicobacter pylori infection. Helicobacter OMVs carry a plethora of virulence factors, including catalase (KatA), an antioxidant enzyme that counteracts the host respiratory burst. We found KatA to be enriched and surface-associated in OMVs compared to bacterial cells. This conferred OMV-dependent KatA activity resulting in neutralization of H2O2 and NaClO, and rescue of surrounding bacteria from oxidative damage. The antioxidant activity of OMVs was abolished by deletion of KatA. In conclusion, enrichment of antioxidative KatA in OMVs is highly important for efficient immune evasion.
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Affiliation(s)
- Sujinna Lekmeechai
- Clinical Microbiology and Molecular Pathology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Yu-Ching Su
- Clinical Microbiology and Molecular Pathology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Marta Brant
- Clinical Microbiology and Molecular Pathology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Maria Alvarado-Kristensson
- Clinical Microbiology and Molecular Pathology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Anna Vallström
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| | - Ikenna Obi
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| | - Anna Arnqvist
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| | - Kristian Riesbeck
- Clinical Microbiology and Molecular Pathology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
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26
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Epplein M, Butt J, Zhang Y, Hendrix LH, Abnet CC, Murphy G, Zheng W, Shu XO, Tsugane S, Qiao YL, Taylor PR, Shimazu T, Yoo KY, Park SK, Kim J, Jee SH, Waterboer T, Pawlita M, You WC, Pan KF. Validation of a Blood Biomarker for Identification of Individuals at High Risk for Gastric Cancer. Cancer Epidemiol Biomarkers Prev 2018; 27:1472-1479. [PMID: 30158280 DOI: 10.1158/1055-9965.epi-18-0582] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 06/11/2018] [Accepted: 08/23/2018] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Helicobacter pylori is the leading cause of gastric cancer, yet the majority of infected individuals will not develop neoplasia. Previously, we developed and replicated serologic H. pylori biomarkers for gastric cancer risk among prospective cohorts in East Asia and now seek to validate the performance of these biomarkers in identifying individuals with premalignant lesions. METHODS This cross-sectional study included 1,402 individuals from Linqu County screened by upper endoscopy. H. pylori protein-specific antibody levels were assessed using multiplex serology. Multivariable-adjusted logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for prevalent intestinal metaplasia, indefinite dysplasia, or dysplasia, compared with superficial or mild atrophic gastritis. RESULTS Compared with individuals seronegative to Omp and HP0305, individuals seropositive to both were seven times more likely to have precancerous lesions (OR, 7.43; 95% CI, 5.59-9.88). A classification model for precancerous lesions that includes age, smoking, and seropositivity to H. pylori, Omp, and HP0305 resulted in an area under the curve (AUC) of 0.751 (95% CI, 0.725-0.777), which is significantly better than the same model, including the established gastric cancer risk factor CagA (AUC, 0.718; 95% CI, 0.691-0.746, P difference = 0.0002). CONCLUSIONS The present study of prevalent precancerous gastric lesions provides support for two new serum biomarkers of gastric cancer risk, Omp and HP 0305. IMPACT Our results support further research into the serological biomarkers Omp and HP0305 as possible improvements over the established virulence marker CagA for identifying individuals with precancerous lesions in East Asia.
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Affiliation(s)
| | - Julia Butt
- German Cancer Research Center, Heidelberg, Germany
| | - Yang Zhang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital and Institute, Beijing, China
| | | | | | - Gwen Murphy
- National Cancer Institute, Rockville, Maryland
| | - Wei Zheng
- Vanderbilt University, Nashville, Tennessee
| | | | | | - You-Lin Qiao
- Chinese Academy of Medical Sciences, Beijing, China
| | | | | | | | - Sue K Park
- Seoul National University, Seoul, Republic of Korea
| | - Jeongseon Kim
- National Cancer Center of Korea, Gyeonggi-do, Republic of Korea
| | - Sun Ha Jee
- Yonsei University, Seoul, Republic of Korea
| | | | | | - Wei-Cheng You
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital and Institute, Beijing, China
| | - Kai-Feng Pan
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital and Institute, Beijing, China.
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27
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Thioloxidoreductase HP0231 of Helicobacter pylori impacts HopQ-dependent CagA translocation. Int J Med Microbiol 2018; 308:977-985. [PMID: 30131271 DOI: 10.1016/j.ijmm.2018.08.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 07/25/2018] [Accepted: 08/05/2018] [Indexed: 02/07/2023] Open
Abstract
Thioloxidoreductase HP0231 of Helicobacter pylori plays essential roles in gastric colonization and related gastric pathology. Comparative proteomics and analysis of complexes between HP0231 and its protein substrates suggested that several Hop proteins are its targets. HP0231 is a dimeric oxidoreductase that functions in an oxidizing Dsb (disulfide bonds) pathway of H. pylori. H. pylori HopQ possesses six cysteine residues, which generate three consecutive disulfide bridges. Comparison of the redox state of HopQ in wild-type cells to that in hp0231-mutated cells clearly indicated that HopQ is a substrate of HP0231. HopQ binds CEACAM1, 3, 5 and 6 (carcinoembryonic antigen-related cell adhesion molecules). This interaction enables T4SS-mediated translocation of CagA into host cells and induces host signaling. Site directed mutagenesis of HopQ (changing cysteine residues into serine) and analysis of the functioning of HopQ variants showed that HP0231 influences the delivery of CagA into host cells, in part through its impact on HopQ redox state. Introduction of a C382S mutation into HopQ significantly affects its reaction with CEACAM receptors, which disturbs T4SS functioning and CagA delivery. An additional effect of HP0231 on other adhesins and their redox state, resulting in their functional impairment, cannot be excluded.
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28
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Yuan XY, Wang Y, Wang MY. The type IV secretion system in Helicobacter pylori. Future Microbiol 2018; 13:1041-1054. [PMID: 29927340 DOI: 10.2217/fmb-2018-0038] [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] [Indexed: 12/15/2022] Open
Abstract
Helicobacter pylori (H. pylori) has an essential role in the pathogenesis of gastritis, peptic ulcer disease, mucosa-associated lymphoid tissue lymphoma and gastric cancer. The severity of the host inflammatory responses against the bacteria have been straightly associated with a special bacterial virulence factor, the cag pathogenicity island, which is a type IV secretion system (T4SS) to deliver CagA into the host cells. Besides cag-T4SS, the chromosomes of H. pylori can encode another three T4SSs, including comB, tfs3 and tfs4. In this review, we systematically reviewed the four T4SSs of H. pylori and explored their roles in the pathogenesis of gastroduodenal diseases. The information summarized in this review might provide valuable insights into the pathogenic mechanism for H. pylori.
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Affiliation(s)
- Xiao-Yan Yuan
- Department of Central Lab, Weihai Municipal Hospital Affiliated to Dalian Medical University, Weihai, Shandong, 264200, PR China
| | - Ying Wang
- Department of Central Lab, Weihai Municipal Hospital Affiliated to Dalian Medical University, Weihai, Shandong, 264200, PR China
| | - Ming-Yi Wang
- Department of Central Lab, Weihai Municipal Hospital Affiliated to Dalian Medical University, Weihai, Shandong, 264200, PR China
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29
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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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30
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Habimana O, Zanoni M, Vitale S, O'Neill T, Scholz D, Xu B, Casey E. One particle, two targets: A combined action of functionalised gold nanoparticles, against Pseudomonas fluorescens biofilms. J Colloid Interface Sci 2018; 526:419-428. [PMID: 29763820 DOI: 10.1016/j.jcis.2018.05.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 05/04/2018] [Accepted: 05/07/2018] [Indexed: 01/06/2023]
Abstract
Attempts to deal with the problem of detrimental biofilms using nanoparticle technologies have generally focussed on exploiting biocidal approaches. However, it is now recognised that biofilm matrix-components may be targets for the disruption or dispersion of biofilms. Here, we show that the functionalization of gold nanoparticles with the enzyme, proteinase-K (PK) led to both biocidal and matrix disruption effects within Pseudomonas fluorescens biofilms and released cells. This study highlights the potential mechanisms underpinning the properties of Proteinase-K functionalized gold nanoparticles. With the emergence of biocide-resistant biofilm-forming organisms, novel nanoparticle strategies may provide the ideal solution for disrupting and inactivating biofilm cells, thereby minimising the use of biocides or antibiotics.
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Affiliation(s)
- Olivier Habimana
- The University of Hong Kong, School of Biological Sciences, Pokfulam, Hong Kong Special Administrative Region
| | - Michele Zanoni
- School of Chemical and Bioprocess Engineering, University College Dublin (UCD), Belfield, Dublin 4, Ireland
| | - Stefania Vitale
- School of Chemical and Bioprocess Engineering, University College Dublin (UCD), Belfield, Dublin 4, Ireland
| | - Tiina O'Neill
- Conway Institute, University College Dublin (UCD), Belfield, Dublin 4, Ireland
| | - Dimitri Scholz
- Conway Institute, University College Dublin (UCD), Belfield, Dublin 4, Ireland
| | - Bin Xu
- School of Chemical and Bioprocess Engineering, University College Dublin (UCD), Belfield, Dublin 4, Ireland
| | - Eoin Casey
- School of Chemical and Bioprocess Engineering, University College Dublin (UCD), Belfield, Dublin 4, Ireland.
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31
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Webb CT, Chandrapala D, Oslan SN, Bamert RS, Grinter RD, Dunstan RA, Gorrell RJ, Song J, Strugnell RA, Lithgow T, Kwok T. Reductive evolution in outer membrane protein biogenesis has not compromised cell surface complexity in Helicobacter pylori. Microbiologyopen 2017; 6. [PMID: 29055967 PMCID: PMC5727368 DOI: 10.1002/mbo3.513] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 05/19/2017] [Accepted: 05/25/2017] [Indexed: 12/18/2022] Open
Abstract
Helicobacter pylori is a gram‐negative bacterial pathogen that chronically inhabits the human stomach. To survive and maintain advantage, it has evolved unique host–pathogen interactions mediated by Helicobacter‐specific proteins in the bacterial outer membrane. These outer membrane proteins (OMPs) are anchored to the cell surface via a C‐terminal β‐barrel domain, which requires their assembly by the β‐barrel assembly machinery (BAM). Here we have assessed the complexity of the OMP C‐terminal β‐barrel domains employed by H. pylori, and characterized the H. pyloriBAM complex. Around 50 Helicobacter‐specific OMPs were assessed with predictive structural algorithms. The data suggest that H. pylori utilizes a unique β‐barrel architecture that might constitute H. pylori‐specific Type V secretions system. The structural and functional diversity in these proteins is encompassed by their extramembrane domains. Bioinformatic and biochemical characterization suggests that the low β‐barrel‐complexity requires only minimalist assembly machinery. The H. pylori proteins BamA and BamD associate to form a BAM complex, with features of BamA enabling an oligomerization that might represent a mechanism by which a minimalist BAM complex forms a larger, sophisticated machinery capable of servicing the outer membrane proteome of H. pylori.
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Affiliation(s)
- Chaille T. Webb
- Infection & Immunity ProgramBiomedicine Discovery Institute and Department of MicrobiologyMonash UniversityClaytonAustralia
| | - Dilini Chandrapala
- Infection & Immunity ProgramBiomedicine Discovery Institute and Department of MicrobiologyMonash UniversityClaytonAustralia
- Infection & Immunity ProgramBiomedicine Discovery Institute and Department of Biochemistry and Molecular BiologyMonash UniversityClaytonAustralia
| | - Siti Nurbaya Oslan
- Infection & Immunity ProgramBiomedicine Discovery Institute and Department of MicrobiologyMonash UniversityClaytonAustralia
- Department of BiochemistryFaculty of Biotechnology and Biomolecular SciencesUniversiti Putra MalaysiaSerdangSelangorMalaysia
- Enzyme and Microbial Technology Research CenterUniversiti Putra MalaysiaSerdangSelangorMalaysia
| | - Rebecca S. Bamert
- Infection & Immunity ProgramBiomedicine Discovery Institute and Department of MicrobiologyMonash UniversityClaytonAustralia
| | - Rhys D. Grinter
- Infection & Immunity ProgramBiomedicine Discovery Institute and Department of MicrobiologyMonash UniversityClaytonAustralia
| | - Rhys A. Dunstan
- Infection & Immunity ProgramBiomedicine Discovery Institute and Department of MicrobiologyMonash UniversityClaytonAustralia
| | - Rebecca J. Gorrell
- Infection & Immunity ProgramBiomedicine Discovery Institute and Department of MicrobiologyMonash UniversityClaytonAustralia
- Infection & Immunity ProgramBiomedicine Discovery Institute and Department of Biochemistry and Molecular BiologyMonash UniversityClaytonAustralia
| | - Jiangning Song
- Infection & Immunity ProgramBiomedicine Discovery Institute and Department of Biochemistry and Molecular BiologyMonash UniversityClaytonAustralia
- Monash Centre for Data ScienceFaculty of Information TechnologyMonash UniversityMelbourneAustralia
| | - Richard A. Strugnell
- Department of Microbiology & ImmunologyUniversity of MelbourneParkvilleAustralia
| | - Trevor Lithgow
- Infection & Immunity ProgramBiomedicine Discovery Institute and Department of MicrobiologyMonash UniversityClaytonAustralia
| | - Terry Kwok
- Infection & Immunity ProgramBiomedicine Discovery Institute and Department of MicrobiologyMonash UniversityClaytonAustralia
- Infection & Immunity ProgramBiomedicine Discovery Institute and Department of Biochemistry and Molecular BiologyMonash UniversityClaytonAustralia
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McClain MS, Beckett AC, Cover TL. Helicobacter pylori Vacuolating Toxin and Gastric Cancer. Toxins (Basel) 2017; 9:toxins9100316. [PMID: 29023421 PMCID: PMC5666363 DOI: 10.3390/toxins9100316] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 10/03/2017] [Accepted: 10/05/2017] [Indexed: 12/13/2022] Open
Abstract
Helicobacter pylori VacA is a channel-forming toxin unrelated to other known bacterial toxins. Most H. pylori strains contain a vacA gene, but there is marked variation among strains in VacA toxin activity. This variation is attributable to strain-specific variations in VacA amino acid sequences, as well as variations in the levels of VacA transcription and secretion. In this review, we discuss epidemiologic studies showing an association between specific vacA allelic types and gastric cancer, as well as studies that have used animal models to investigate VacA activities relevant to gastric cancer. We also discuss the mechanisms by which VacA-induced cellular alterations may contribute to the pathogenesis of gastric cancer.
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Affiliation(s)
- Mark S McClain
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - Amber C Beckett
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
| | - Timothy L Cover
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN 37212, USA.
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Helicobacter pylori antigenic Lpp20 is a structural homologue of Tipα and promotes epithelial-mesenchymal transition. Biochim Biophys Acta Gen Subj 2017; 1861:3263-3271. [PMID: 28947343 DOI: 10.1016/j.bbagen.2017.09.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 09/07/2017] [Accepted: 09/21/2017] [Indexed: 02/07/2023]
Abstract
BACKGROUND Helicobacter pylori is a bacterium that affects about 50% of the world population and, despite being often asymptomatic, it is responsible of several gastric diseases, from gastritis to gastric cancer. The protein Lpp20 (HP1456) plays an important role in bacterium survival and host colonization, but the possibility that it might be involved in the etiology of H. pylori-related disorders is an unexplored issue. Lpp20 is a lipoprotein bound to the external membrane of the bacterium, but it is also secreted inside vesicles along with other two proteins of the same operon, i.e. HP1454 and HP1457. RESULTS In this study we determined the crystal structure of Lpp20 and we found that it has a fold similar to a carcinogenic factor released by H. pylori, namely Tipα. We demonstrate that Lpp20 promotes cell migration and E-cadherin down-regulation in gastric cancer cells, two events recalling the epithelial-mesenchymal transition (EMT) process. Differently from Tipα, Lpp20 also stimulates cell proliferation. CONCLUSIONS This identifies Lpp20 as a new pathogenic factor produced by H. pylori that promotes EMT and thereby the progression of cancer to the metastatic state.
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The Middle Fragment of Helicobacter pylori CagA Induces Actin Rearrangement and Triggers Its Own Uptake into Gastric Epithelial Cells. Toxins (Basel) 2017; 9:toxins9080237. [PMID: 28788072 PMCID: PMC5577571 DOI: 10.3390/toxins9080237] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 07/07/2017] [Accepted: 07/26/2017] [Indexed: 01/14/2023] Open
Abstract
Cytotoxin-associated gene product A (CagA) is a major virulence factor secreted by Helicobacter pylori. CagA activity in the gastric epithelium is associated with higher risk of gastric cancer development. Bacterial type IV secretion system (T4SS)-mediated translocation of CagA into the cytosol of human epithelial cells occurs via a poorly understood mechanism that requires CagA interaction with the host membrane lipid phosphatidylserine (PS) and host cell receptor integrin α5β1. Here we have characterized the isolated recombinant middle fragment of CagA (CagA-M) that contains the positively-charged PS-binding region (aa 613–636) and a putative β1 integrin binding site, but lacks the EPIYA region, secretion signal peptide and the CagA multimerization motif. We show that CagA-M, when immobilized on latex beads, is capable of binding to, and triggering its own uptake into, gastric epithelial cells in the absence of infection with cagA-positive H. pylori. Using site-directed mutagenesis, fluorescent and electron microscopy, and highly-specific inhibitors, we demonstrate that the cell-binding and endocytosis-like internalization of CagA-M are dependent on (1) binding to PS; (2) β1 integrin activity; and (3) actin dynamics. Interaction of CagA-M with the host cells is accompanied by the development of long filopodia-like protrusions (macrospikes). This novel morphology is different from the hummingbird phenotype induced by the translocation of full-length CagA. The determinants within CagA-M and within the host that are important for endocytosis-like internalization into host cells are very similar to those observed for T4SS-mediated internalization of full-length CagA, suggesting that the latter may involve an endocytic pathway.
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Horvatić A, Kuleš J, Guillemin N, Galan A, Mrljak V, Bhide M. High-throughput proteomics and the fight against pathogens. MOLECULAR BIOSYSTEMS 2017; 12:2373-84. [PMID: 27227577 DOI: 10.1039/c6mb00223d] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Pathogens pose a major threat to human and animal welfare. Understanding the interspecies host-pathogen protein-protein interactions could lead to the development of novel strategies to combat infectious diseases through the rapid development of new therapeutics. The first step in understanding the host-pathogen crosstalk is to identify interacting proteins in order to define crucial hot-spots in the host-pathogen interactome, such as the proposed pharmaceutical targets by means of high-throughput proteomic methodologies. In order to obtain holistic insight into the inter- and intra-species bimolecular interactions, apart from the proteomic approach, sophisticated in silico modeling is used to correlate the obtained large data sets with other omics data and clinical outcomes. Since the main focus in this area has been directed towards human medicine, it is time to extrapolate the existing expertise to a new emerging field: the 'systems veterinary medicine'. Therefore, this review addresses high-throughput mass spectrometry-based technology for monitoring protein-protein interactions in vitro and in vivo and discusses pathogen cultivation, model host cells and available bioinformatic tools employed in vaccine development.
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Affiliation(s)
- Anita Horvatić
- ERA Chair VetMedZg Project, Internal Diseases Clinic, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10 000 Zagreb, Croatia.
| | - Josipa Kuleš
- ERA Chair VetMedZg Project, Internal Diseases Clinic, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10 000 Zagreb, Croatia.
| | - Nicolas Guillemin
- ERA Chair VetMedZg Project, Internal Diseases Clinic, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10 000 Zagreb, Croatia.
| | - Asier Galan
- ERA Chair VetMedZg Project, Internal Diseases Clinic, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10 000 Zagreb, Croatia.
| | - Vladimir Mrljak
- ERA Chair VetMedZg Project, Internal Diseases Clinic, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10 000 Zagreb, Croatia.
| | - Mangesh Bhide
- ERA Chair VetMedZg Project, Internal Diseases Clinic, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10 000 Zagreb, Croatia. and Laboratory of Biomedical Microbiology and Immunology, University of Veterinary Medicine and Pharmacy, Kosice, Slovakia and Institute of Neuroimmunology, Slovakia Academy of Sciences, Bratislava, Slovakia
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Poppleton DI, Duchateau M, Hourdel V, Matondo M, Flechsler J, Klingl A, Beloin C, Gribaldo S. Outer Membrane Proteome of Veillonella parvula: A Diderm Firmicute of the Human Microbiome. Front Microbiol 2017; 8:1215. [PMID: 28713344 PMCID: PMC5491611 DOI: 10.3389/fmicb.2017.01215] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 06/14/2017] [Indexed: 12/24/2022] Open
Abstract
Veillonella parvula is a biofilm-forming commensal found in the lungs, vagina, mouth, and gastro-intestinal tract of humans, yet it may develop into an opportunistic pathogen. Furthermore, the presence of Veillonella has been associated with the development of a healthy immune system in infants. Veillonella belongs to the Negativicutes, a diverse clade of bacteria that represent an evolutionary enigma: they phylogenetically belong to Gram-positive (monoderm) Firmicutes yet maintain an outer membrane (OM) with lipopolysaccharide similar to classic Gram-negative (diderm) bacteria. The OMs of Negativicutes have unique characteristics including the replacement of Braun's lipoprotein by OmpM for tethering the OM to the peptidoglycan. Through phylogenomic analysis, we have recently provided bioinformatic annotation of the Negativicutes diderm cell envelope. We showed that it is a unique type of envelope that was present in the ancestor of present-day Firmicutes and lost multiple times independently in this phylum, giving rise to the monoderm architecture; however, little experimental data is presently available for any Negativicutes cell envelope. Here, we performed the first experimental proteomic characterization of the cell envelope of a diderm Firmicute, producing an OM proteome of V. parvula. We initially conducted a thorough bioinformatics analysis of all 1,844 predicted proteins from V. parvula DSM 2008's genome using 12 different localization prediction programs. These results were complemented by protein extraction with surface exposed (SE) protein tags and by subcellular fractionation, both of which were analyzed by liquid chromatography tandem mass spectrometry. The merging of proteomics and bioinformatics results allowed identification of 78 OM proteins. These include a number of receptors for TonB-dependent transport, the main component of the BAM system for OM protein biogenesis (BamA), the Lpt system component LptD, which is responsible for insertion of LPS into the OM, and several copies of the major OmpM protein. The annotation of V. parvula's OM proteome markedly extends previous inferences on the nature of the cell envelope of Negativicutes, including the experimental evidence of a BAM/TAM system for OM protein biogenesis and of a complete Lpt system for LPS transport to the OM. It also provides important information on the role of OM components in the lifestyle of Veillonella, such as a possible gene cluster for O-antigen synthesis and a large number of adhesins. Finally, many OM hypothetical proteins were identified, which are priority targets for further characterization.
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Affiliation(s)
- Daniel I. Poppleton
- Unité de Biologie Moléculaire du Gène chez les Extrêmophiles, Département de Microbiologie, Institut PasteurParis, France
| | - Magalie Duchateau
- Unité de Spectrométrie de Masse Structurale et Protéomique, Plateforme Protéomique, Départment de Biologie Structurale et Chime, Institut Pasteur, USR 2000 Centre National de la Recherche ScientifiqueParis, France
| | - Véronique Hourdel
- Unité de Spectrométrie de Masse Structurale et Protéomique, Plateforme Protéomique, Départment de Biologie Structurale et Chime, Institut Pasteur, USR 2000 Centre National de la Recherche ScientifiqueParis, France
| | - Mariette Matondo
- Unité de Spectrométrie de Masse Structurale et Protéomique, Plateforme Protéomique, Départment de Biologie Structurale et Chime, Institut Pasteur, USR 2000 Centre National de la Recherche ScientifiqueParis, France
| | - Jennifer Flechsler
- Pflanzliche Entwicklungsbiologie und Elektronenmikroskopie, Department I. Botanik, Biozentrum der LMU MünchenPlanegg-Martinsried, Germany
| | - Andreas Klingl
- Pflanzliche Entwicklungsbiologie und Elektronenmikroskopie, Department I. Botanik, Biozentrum der LMU MünchenPlanegg-Martinsried, Germany
| | - Christophe Beloin
- Unité de Génétique des Biofilms, Département de Microbiologie, Institut PasteurParis, France
| | - Simonetta Gribaldo
- Unité de Biologie Moléculaire du Gène chez les Extrêmophiles, Département de Microbiologie, Institut PasteurParis, France
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Hutton ML, D'Costa K, Rossiter AE, Wang L, Turner L, Steer DL, Masters SL, Croker BA, Kaparakis-Liaskos M, Ferrero RL. A Helicobacter pylori Homolog of Eukaryotic Flotillin Is Involved in Cholesterol Accumulation, Epithelial Cell Responses and Host Colonization. Front Cell Infect Microbiol 2017; 7:219. [PMID: 28634572 PMCID: PMC5460342 DOI: 10.3389/fcimb.2017.00219] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Accepted: 05/11/2017] [Indexed: 12/12/2022] Open
Abstract
The human pathogen Helicobacter pylori acquires cholesterol from membrane raft domains in eukaryotic cells, commonly known as "lipid rafts." Incorporation of this cholesterol into the H. pylori cell membrane allows the bacterium to avoid clearance by the host immune system and to resist the effects of antibiotics and antimicrobial peptides. The presence of cholesterol in H. pylori bacteria suggested that this pathogen may have cholesterol-enriched domains within its membrane. Consistent with this suggestion, we identified a hypothetical H. pylori protein (HP0248) with homology to the flotillin proteins normally found in the cholesterol-enriched domains of eukaryotic cells. As shown for eukaryotic flotillin proteins, HP0248 was detected in detergent-resistant membrane fractions of H. pylori. Importantly, H. pylori HP0248 mutants contained lower levels of cholesterol than wild-type bacteria (P < 0.01). HP0248 mutant bacteria also exhibited defects in type IV secretion functions, as indicated by reduced IL-8 responses and CagA translocation in epithelial cells (P < 0.05), and were less able to establish a chronic infection in mice than wild-type bacteria (P < 0.05). Thus, we have identified an H. pylori flotillin protein and shown its importance for bacterial virulence. Taken together, the data demonstrate important roles for H. pylori flotillin in host-pathogen interactions. We propose that H. pylori flotillin may be required for the organization of virulence proteins into membrane raft-like structures in this pathogen.
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Affiliation(s)
- Melanie L. Hutton
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical ResearchMelbourne, VIC, Australia
| | - Kimberley D'Costa
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical ResearchMelbourne, VIC, Australia
| | - Amanda E. Rossiter
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical ResearchMelbourne, VIC, Australia
| | - Lin Wang
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical ResearchMelbourne, VIC, Australia
| | - Lorinda Turner
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical ResearchMelbourne, VIC, Australia
| | - David L. Steer
- Monash Biomedical Proteomics Facility, Monash UniversityMelbourne, VIC, Australia
| | - Seth L. Masters
- Inflammation Division, The Walter and Eliza Hall InstituteMelbourne, VIC, Australia
| | - Ben A. Croker
- Inflammation Division, The Walter and Eliza Hall InstituteMelbourne, VIC, Australia
| | - Maria Kaparakis-Liaskos
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical ResearchMelbourne, VIC, Australia
| | - Richard L. Ferrero
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical ResearchMelbourne, VIC, Australia
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Microbiology, Monash UniversityMelbourne, VIC, Australia
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Bernardini G, Figura N, Ponzetto A, Marzocchi B, Santucci A. Application of proteomics to the study of Helicobacter pylori and implications for the clinic. Expert Rev Proteomics 2017; 14:477-490. [PMID: 28513226 DOI: 10.1080/14789450.2017.1331739] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Helicobacter pylori (H. pylori) is a gram-negative bacterium that colonizes the gastric epithelium and mucous layer of more than half the world's population. H. pylori is a primary human pathogen, responsible for the development of chronic gastritis, peptic ulceration and gastric cancer. Proteomics is impacting several aspects of medical research: understanding the molecular basis of infection and disease manifestation, identification of therapeutic targets and discovery of clinically relevant biomarkers. Areas covered: The main aim of the present review is to provide a comprehensive overview of the contribution of proteomics to the study of H. pylori infection pathophysiology. In particular, we focused on the role of the bacterium and its most important virulence factor, CagA, in the progression of gastric cells transformation and cancer progression. We also discussed the proteomic approaches aimed at the investigation of the host response to bacterial infection. Expert commentary: In the field of proteomics of H. pylori, comprehensive analysis of clinically relevant proteins (functional proteomics) rather than entire proteomes will result in important medical outcomes. Finally, we provided an outlook on the potential development of proteomics in H. pylori research.
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Affiliation(s)
- Giulia Bernardini
- a Dipartimento di Biotecnologie , Chimica e Farmacia, Università degli Studi di Siena , Siena , Italy
| | - Natale Figura
- a Dipartimento di Biotecnologie , Chimica e Farmacia, Università degli Studi di Siena , Siena , Italy
| | - Antonio Ponzetto
- b Dipartimento di Scienze Mediche , Università degli Studi di Torino , Torino , Italy
| | - Barbara Marzocchi
- a Dipartimento di Biotecnologie , Chimica e Farmacia, Università degli Studi di Siena , Siena , Italy
| | - Annalisa Santucci
- a Dipartimento di Biotecnologie , Chimica e Farmacia, Università degli Studi di Siena , Siena , Italy
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39
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Merino E, Flores-Encarnación M, Aguilar-Gutiérrez GR. Functional interaction and structural characteristics of unique components of Helicobacter pylori T4SS. FEBS J 2017; 284:3540-3549. [PMID: 28470874 DOI: 10.1111/febs.14092] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 03/14/2017] [Accepted: 04/26/2017] [Indexed: 12/25/2022]
Abstract
The Helicobacter pylori infection of the human gastric mucosa causes chronic active gastritis and peptic ulcers and is associated with the development of gastric cancer. Epidemiological studies show that these gastric diseases are related to virulent H. pylori strains that harbor the cytotoxin-associated gene pathogenicity island (cag PAI). The cag PAI is a DNA insertion in the H. pylori chromosome that encodes ~ 27 proteins, including the oncoprotein CagA. Approximately 20 of these proteins have been designated as cag type IV secretion system (T4SS) components. However, only 11 of these proteins share function, structure, and/or sequence similarities with the prototypical VirB/VirD4 T4SS of Agrobacterium tumefaciens. The VirB/VirD4 orthologs of the cag T4SS of H. pylori are required for CagA translocation and stimulate the gastric epithelial cells to produce and secrete interleukin-8 (IL-8). The cag PAI encodes eight additional proteins, such as Cag3 (Cagδ/HP0522), CagM (Cag16/HP0537), CagU (Cag11/HP0531), CagI (Cag19/HP0540), and CagH (Cag20/HP0541), which are also required for the translocation of CagA and IL-8 secretion, meanwhile CagF (Cag22/HP0543), CagG (Cag21/HP0542), and CagZ (Cag6/HP0526) are just required for the translocation of CagA. However, relatively little is known about their functions and structural organization because they exhibit a nondetectable sequence similarity with T4SS components in the current databases. In this review, we conducted an exhaustive analysis of the literature to present the biochemistry, putative role, localization, and interactions of each of these eight additional cag T4SS components.
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Affiliation(s)
- Enrique Merino
- Enrique Merino, Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Marcos Flores-Encarnación
- Marcos Flores-Encarnación, Laboratorio de Microbiología Molecular y Celular, Facultad de Medicina, Benemérita Universidad Autónoma de Puebla, Puebla, México
| | - Germán Rubén Aguilar-Gutiérrez
- Germán Rubén Aguilar-Gutiérrez, Centro de Investigación Sobre Enfermedades Infecciosas, Instituto Nacional de Salud Pública, Cuernavaca, Morelos, México
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40
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Bastos PAD, da Costa JP, Vitorino R. A glimpse into the modulation of post-translational modifications of human-colonizing bacteria. J Proteomics 2016; 152:254-275. [PMID: 27888141 DOI: 10.1016/j.jprot.2016.11.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 10/22/2016] [Accepted: 11/07/2016] [Indexed: 12/19/2022]
Abstract
Protein post-translational modifications (PTMs) are a key bacterial feature that holds the capability to modulate protein function and responses to environmental cues. Until recently, their role in the regulation of prokaryotic systems has been largely neglected. However, the latest developments in mass spectrometry-based proteomics have allowed an unparalleled identification and quantification of proteins and peptides that undergo PTMs in bacteria, including in species which directly or indirectly affect human health. Herein, we address this issue by carrying out the largest and most comprehensive global pooling and comparison of PTM peptides and proteins from bacterial species performed to date. Data was collected from 91 studies relating to PTM bacterial peptides or proteins identified by mass spectrometry-based methods. The present analysis revealed that there was a considerable overlap between PTMs across species, especially between acetylation and other PTMs, particularly succinylation. Phylogenetically closer species may present more overlapping phosphoproteomes, but environmental triggers also contribute to this proximity. PTMs among bacteria were found to be extremely versatile and diverse, meaning that the same protein may undergo a wide variety of different modifications across several species, but it could also suffer different modifications within the same species.
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Affiliation(s)
- Paulo André Dias Bastos
- Department of Medical Sciences, Institute for Biomedicine-iBiMED, University of Aveiro, Aveiro, Portugal; Department of Chemistry, University of Aveiro, Portugal
| | | | - Rui Vitorino
- Department of Medical Sciences, Institute for Biomedicine-iBiMED, University of Aveiro, Aveiro, Portugal; Department of Physiology and Cardiothoracic Surgery, Faculty of Medicine, University of Porto, Porto, Portugal.
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41
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Karlsson R, Thorell K, Hosseini S, Kenny D, Sihlbom C, Sjöling Å, Karlsson A, Nookaew I. Comparative Analysis of Two Helicobacter pylori Strains using Genomics and Mass Spectrometry-Based Proteomics. Front Microbiol 2016; 7:1757. [PMID: 27891114 PMCID: PMC5104757 DOI: 10.3389/fmicb.2016.01757] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 10/19/2016] [Indexed: 12/20/2022] Open
Abstract
Helicobacter pylori, a gastroenteric pathogen believed to have co-evolved with humans over 100,000 years, shows significant genetic variability. This motivates the study of different H. pylori strains and the diseases they cause in order to identify determinants for disease evolution. In this study, we used proteomics tools to compare two H. pylori strains. Nic25_A was isolated in Nicaragua from a patient with intestinal metaplasia, and P12 was isolated in Europe from a patient with duodenal ulcers. Differences in the abundance of surface proteins between the two strains were determined with two mass spectrometry-based methods, label-free quantification (MaxQuant) or the use of tandem mass tags (TMT). Each approach used a lipid-based protein immobilization (LPITM) technique to enrich peptides of surface proteins. Using the MaxQuant software, we found 52 proteins that differed significantly in abundance between the two strains (up- or downregulated by a factor of 1.5); with TMT, we found 18 proteins that differed in abundance between the strains. Strain P12 had a higher abundance of proteins encoded by the cag pathogenicity island, while levels of the acid response regulator ArsR and its regulatory targets (KatA, AmiE, and proteins involved in urease production) were higher in strain Nic25_A. Our results show that differences in protein abundance between H. pylori strains can be detected with proteomic approaches; this could have important implications for the study of disease progression.
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Affiliation(s)
- Roger Karlsson
- Nanoxis Consulting ABGothenburg, Sweden; Department of Infectious Diseases, Sahlgrenska Academy, University of GothenburgGothenburg, Sweden
| | - Kaisa Thorell
- Department of Microbiology and Immunology, University of GothenburgGothenburg, Sweden; Department of Biology and Biological Engineering, Chalmers University of TechnologyGothenburg, Sweden
| | - Shaghayegh Hosseini
- Department of Biology and Biological Engineering, Chalmers University of Technology Gothenburg, Sweden
| | - Diarmuid Kenny
- Proteomics Core Facility, Sahlgrenska Academy, University of Gothenburg Gothenburg, Sweden
| | - Carina Sihlbom
- Proteomics Core Facility, Sahlgrenska Academy, University of Gothenburg Gothenburg, Sweden
| | - Åsa Sjöling
- Department of Microbiology and Immunology, University of Gothenburg Gothenburg, Sweden
| | | | - Intawat Nookaew
- Department of Biology and Biological Engineering, Chalmers University of TechnologyGothenburg, Sweden; Department of Biomedical Informatics, College of Medicine, University of Arkansas for Medical Sciences, Little RockAR, USA
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Szewczyk J, Collet JF. The Journey of Lipoproteins Through the Cell: One Birthplace, Multiple Destinations. Adv Microb Physiol 2016; 69:1-50. [PMID: 27720009 DOI: 10.1016/bs.ampbs.2016.07.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Bacterial lipoproteins are a very diverse group of proteins characterized by the presence of an N-terminal lipid moiety that serves as a membrane anchor. Lipoproteins have a wide variety of crucial functions, ranging from envelope biogenesis to stress response. In Gram-negative bacteria, lipoproteins can be targeted to various destinations in the cell, including the periplasmic side of the cytoplasmic or outer membrane, the cell surface or the external milieu. The sorting mechanisms have been studied in detail in Escherichia coli, but exceptions to the rules established in this model bacterium exist in other bacteria. In this chapter, we will present the current knowledge on lipoprotein sorting in the cell. Our particular focus will be on the surface-exposed lipoproteins that appear to be much more common than previously assumed. We will discuss the different targeting strategies, provide numerous examples of surface-exposed lipoproteins and discuss the techniques used to assess their surface exposure.
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Affiliation(s)
- J Szewczyk
- WELBIO, Brussels, Belgium; de Duve Institute, Université catholique de Louvain, Brussels, Belgium
| | - J-F Collet
- WELBIO, Brussels, Belgium; de Duve Institute, Université catholique de Louvain, Brussels, Belgium.
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43
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A Nonoligomerizing Mutant Form of Helicobacter pylori VacA Allows Structural Analysis of the p33 Domain. Infect Immun 2016; 84:2662-70. [PMID: 27382020 PMCID: PMC4995914 DOI: 10.1128/iai.00254-16] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 06/24/2016] [Indexed: 12/17/2022] Open
Abstract
Helicobacter pylori secretes a pore-forming VacA toxin that has structural features and activities substantially different from those of other known bacterial toxins. VacA can assemble into multiple types of water-soluble flower-shaped oligomeric structures, and most VacA activities are dependent on its capacity to oligomerize. The 88-kDa secreted VacA protein can undergo limited proteolysis to yield two domains, designated p33 and p55. The p33 domain is required for membrane channel formation and intracellular toxic activities, and the p55 domain has an important role in mediating VacA binding to cells. Previous studies showed that the p55 domain has a predominantly β-helical structure, but no structural data are available for the p33 domain. We report here the purification and analysis of a nonoligomerizing mutant form of VacA secreted by H. pylori The nonoligomerizing 88-kDa mutant protein retains the capacity to enter host cells but lacks detectable toxic activity. Analysis of crystals formed by the monomeric protein reveals that the β-helical structure of the p55 domain extends into the C-terminal portion of p33. Fitting the p88 structural model into an electron microscopy map of hexamers formed by wild-type VacA (predicted to be structurally similar to VacA membrane channels) reveals that p55 and the β-helical segment of p33 localize to peripheral arms but do not occupy the central region of the hexamers. We propose that the amino-terminal portion of p33 is unstructured when VacA is in a monomeric form and that it undergoes a conformational change during oligomer assembly.
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Konovalova A, Silhavy TJ. Outer membrane lipoprotein biogenesis: Lol is not the end. Philos Trans R Soc Lond B Biol Sci 2016; 370:rstb.2015.0030. [PMID: 26370942 DOI: 10.1098/rstb.2015.0030] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Bacterial lipoproteins are lipid-anchored proteins that contain acyl groups covalently attached to the N-terminal cysteine residue of the mature protein. Lipoproteins are synthesized in precursor form with an N-terminal signal sequence (SS) that targets translocation across the cytoplasmic or inner membrane (IM). Lipid modification and SS processing take place at the periplasmic face of the IM. Outer membrane (OM) lipoproteins take the localization of lipoproteins (Lol) export pathway, which ends with the insertion of the N-terminal lipid moiety into the inner leaflet of the OM. For many lipoproteins, the biogenesis pathway ends here. We provide examples of lipoproteins that adopt complex topologies in the OM that include transmembrane and surface-exposed domains. Biogenesis of such lipoproteins requires additional steps beyond the Lol pathway. In at least one case, lipoprotein sequences reach the cell surface by being threaded through the lumen of a beta-barrel protein in an assembly reaction that requires the heteropentomeric Bam complex. The inability to predict surface exposure reinforces the importance of experimental verification of lipoprotein topology and we will discuss some of the methods used to study OM protein topology.
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Affiliation(s)
- Anna Konovalova
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, Washington Road, Princeton, NJ 08544, USA
| | - Thomas J Silhavy
- Department of Molecular Biology, Lewis Thomas Laboratory, Princeton University, Washington Road, Princeton, NJ 08544, USA
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Foegeding NJ, Caston RR, McClain MS, Ohi MD, Cover TL. An Overview of Helicobacter pylori VacA Toxin Biology. Toxins (Basel) 2016; 8:toxins8060173. [PMID: 27271669 PMCID: PMC4926140 DOI: 10.3390/toxins8060173] [Citation(s) in RCA: 129] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Revised: 05/18/2016] [Accepted: 05/27/2016] [Indexed: 12/11/2022] Open
Abstract
The VacA toxin secreted by Helicobacter pylori enhances the ability of the bacteria to colonize the stomach and contributes to the pathogenesis of gastric adenocarcinoma and peptic ulcer disease. The amino acid sequence and structure of VacA are unrelated to corresponding features of other known bacterial toxins. VacA is classified as a pore-forming toxin, and many of its effects on host cells are attributed to formation of channels in intracellular sites. The most extensively studied VacA activity is its capacity to stimulate vacuole formation, but the toxin has many additional effects on host cells. Multiple cell types are susceptible to VacA, including gastric epithelial cells, parietal cells, T cells, and other types of immune cells. This review focuses on the wide range of VacA actions that are detectable in vitro, as well as actions of VacA in vivo that are relevant for H. pylori colonization of the stomach and development of gastric disease.
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Affiliation(s)
- Nora J Foegeding
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - Rhonda R Caston
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - Mark S McClain
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - Melanie D Ohi
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37232, USA.
| | - Timothy L Cover
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN 37212, USA.
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Molecular and Structural Analysis of the Helicobacter pylori cag Type IV Secretion System Core Complex. mBio 2016; 7:e02001-15. [PMID: 26758182 PMCID: PMC4725015 DOI: 10.1128/mbio.02001-15] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Bacterial type IV secretion systems (T4SSs) can function to export or import DNA, and can deliver effector proteins into a wide range of target cells. Relatively little is known about the structural organization of T4SSs that secrete effector proteins. In this report, we describe the isolation and analysis of a membrane-spanning core complex from the Helicobacter pylori cag T4SS, which has an important role in the pathogenesis of gastric cancer. We show that this complex contains five H. pylori proteins, CagM, CagT, Cag3, CagX, and CagY, each of which is required for cag T4SS activity. CagX and CagY are orthologous to the VirB9 and VirB10 components of T4SSs in other bacterial species, and the other three Cag proteins are unique to H. pylori. Negative stain single-particle electron microscopy revealed complexes 41 nm in diameter, characterized by a 19-nm-diameter central ring linked to an outer ring by spoke-like linkers. Incomplete complexes formed by Δcag3 or ΔcagT mutants retain the 19-nm-diameter ring but lack an organized outer ring. Immunogold labeling studies confirm that Cag3 is a peripheral component of the complex. The cag T4SS core complex has an overall diameter and structural organization that differ considerably from the corresponding features of conjugative T4SSs. These results highlight specialized features of the H. pylori cag T4SS that are optimized for function in the human gastric mucosal environment. Type IV secretion systems (T4SSs) are versatile macromolecular machines that are present in many bacterial species. In this study, we investigated a T4SS found in the bacterium Helicobacter pylori. H. pylori is an important cause of stomach cancer, and the H. pylori T4SS contributes to cancer pathogenesis by mediating entry of CagA (an effector protein regarded as a “bacterial oncoprotein”) into gastric epithelial cells. We isolated and analyzed the membrane-spanning core complex of the H. pylori T4SS and showed that it contains unique proteins unrelated to components of T4SSs in other bacterial species. These results constitute the first structural analysis of the core complex from this important secretion system.
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Aurass P, Gerlach T, Becher D, Voigt B, Karste S, Bernhardt J, Riedel K, Hecker M, Flieger A. Life Stage-specific Proteomes of Legionella pneumophila Reveal a Highly Differential Abundance of Virulence-associated Dot/Icm effectors. Mol Cell Proteomics 2015; 15:177-200. [PMID: 26545400 DOI: 10.1074/mcp.m115.053579] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Indexed: 12/28/2022] Open
Abstract
Major differences in the transcriptional program underlying the phenotypic switch between exponential and post-exponential growth of Legionella pneumophila were formerly described characterizing important alterations in infection capacity. Additionally, a third state is known where the bacteria transform in a viable but nonculturable state under stress, such as starvation. We here describe phase-related proteomic changes in exponential phase (E), postexponential phase (PE) bacteria, and unculturable microcosms (UNC) containing viable but nonculturable state cells, and identify phase-specific proteins. We present data on different bacterial subproteomes of E and PE, such as soluble whole cell proteins, outer membrane-associated proteins, and extracellular proteins. In total, 1368 different proteins were identified, 922 were quantified and 397 showed differential abundance in E/PE. The quantified subproteomes of soluble whole cell proteins, outer membrane-associated proteins, and extracellular proteins; 841, 55, and 77 proteins, respectively, were visualized in Voronoi treemaps. 95 proteins were quantified exclusively in E, such as cell division proteins MreC, FtsN, FtsA, and ZipA; 33 exclusively in PE, such as motility-related proteins of flagellum biogenesis FlgE, FlgK, and FliA; and 9 exclusively in unculturable microcosms soluble whole cell proteins, such as hypothetical, as well as transport/binding-, and metabolism-related proteins. A high frequency of differentially abundant or phase-exclusive proteins was observed among the 91 quantified effectors of the major virulence-associated protein secretion system Dot/Icm (> 60%). 24 were E-exclusive, such as LepA/B, YlfA, MavG, Lpg2271, and 13 were PE-exclusive, such as RalF, VipD, Lem10. The growth phase-related specific abundance of a subset of Dot/Icm virulence effectors was confirmed by means of Western blotting. We therefore conclude that many effectors are predominantly abundant at either E or PE which suggests their phase specific function. The distinct temporal or spatial presence of such proteins might have important implications for functional assignments in the future or for use as life-stage specific markers for pathogen analysis.
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Affiliation(s)
- Philipp Aurass
- From the ‡Robert Koch-Institut, Wernigerode Branch, Division of Enteropathogenic Bacteria and Legionella (FG11), Burgstr. 37, 38855 Wernigerode, Germany
| | - Thomas Gerlach
- From the ‡Robert Koch-Institut, Wernigerode Branch, Division of Enteropathogenic Bacteria and Legionella (FG11), Burgstr. 37, 38855 Wernigerode, Germany
| | - Dörte Becher
- §Institute for Microbiology, Ernst-Moritz-Arndt University Greifswald, Friedrich-Ludwig-Jahn-Str. 15, 17487 Greifswald, Germany
| | - Birgit Voigt
- §Institute for Microbiology, Ernst-Moritz-Arndt University Greifswald, Friedrich-Ludwig-Jahn-Str. 15, 17487 Greifswald, Germany
| | - Susanne Karste
- From the ‡Robert Koch-Institut, Wernigerode Branch, Division of Enteropathogenic Bacteria and Legionella (FG11), Burgstr. 37, 38855 Wernigerode, Germany
| | - Jörg Bernhardt
- §Institute for Microbiology, Ernst-Moritz-Arndt University Greifswald, Friedrich-Ludwig-Jahn-Str. 15, 17487 Greifswald, Germany
| | - Katharina Riedel
- §Institute for Microbiology, Ernst-Moritz-Arndt University Greifswald, Friedrich-Ludwig-Jahn-Str. 15, 17487 Greifswald, Germany
| | - Michael Hecker
- §Institute for Microbiology, Ernst-Moritz-Arndt University Greifswald, Friedrich-Ludwig-Jahn-Str. 15, 17487 Greifswald, Germany
| | - Antje Flieger
- From the ‡Robert Koch-Institut, Wernigerode Branch, Division of Enteropathogenic Bacteria and Legionella (FG11), Burgstr. 37, 38855 Wernigerode, Germany;
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Snider CA, Voss BJ, McDonald WH, Cover TL. Supporting data for analysis of the Helicobacter pylori exoproteome. Data Brief 2015; 5:560-3. [PMID: 26958609 PMCID: PMC4773364 DOI: 10.1016/j.dib.2015.10.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 10/06/2015] [Accepted: 10/06/2015] [Indexed: 01/25/2023] Open
Abstract
The goal of this research was to analyze the composition of the Helicobacter pylori exoproteome at multiple phases of bacterial growth (Snider et al., 2015) [1]. H. pylori was grown in a serum-free medium and at serial time points, aliquots were centrifuged and fractionated to yield culture supernatant, a soluble cellular fraction, and a membrane fraction. Samples were analyzed by single dimensional LC-MS/MS analyses and multidimensional protein identification technology (MudPIT). Here we present data showing the numbers of assigned spectra and proportional abundance of individual proteins in each of the samples analyzed, along with a calculation of the level of enrichment of individual proteins in the supernatant compared to the soluble cellular fraction.
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Affiliation(s)
| | - Bradley J Voss
- Department of Pathology, Microbiology and Immunology, Nashville, TN, USA
| | - W Hayes McDonald
- Proteomics Laboratory, Mass Spectrometry Research Center, Nashville, TN, USA; Department of Biochemistry, Nashville, TN, USA
| | - Timothy L Cover
- Department of Medicine, Nashville, TN, USA; Department of Pathology, Microbiology and Immunology, Nashville, TN, USA; Vanderbilt University School of Medicine; Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN, USA
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Glatter T, Ahrné E, Schmidt A. Comparison of Different Sample Preparation Protocols Reveals Lysis Buffer-Specific Extraction Biases in Gram-Negative Bacteria and Human Cells. J Proteome Res 2015; 14:4472-85. [PMID: 26412744 DOI: 10.1021/acs.jproteome.5b00654] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
We evaluated different in-solution and FASP-based sample preparation strategies for absolute protein quantification. Label-free quantification (LFQ) was employed to compare different sample preparation strategies in the bacterium Pseudomonas aeruginosa and human embryonic kidney cells (HEK), and organismal-specific differences in general performance and enrichment of specific protein classes were noted. The original FASP protocol globally enriched for most proteins in the bacterial sample, whereas the sodium deoxycholate in-solution strategy was more efficient with HEK cells. Although detergents were found to be highly suited for global proteome analysis, higher intensities were obtained for high-abundant nucleic acid-associated protein complexes, like the ribosome and histone proteins, using guanidine hydrochloride. Importantly, we show for the first time that the observable total proteome mass of a sample strongly depends on the sample preparation protocol, with some protocols resulting in a significant underestimation of protein mass due to incomplete protein extraction of biased protein groups. Furthermore, we demonstrate that some of the observed abundance biases can be overcome by incorporating a nuclease treatment step or, alternatively, a correction factor for complementary sample preparation approaches.
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Affiliation(s)
- Timo Glatter
- Proteomics Core Facility, Biozentrum, University of Basel , 4056 Basel, Switzerland
| | - Erik Ahrné
- Proteomics Core Facility, Biozentrum, University of Basel , 4056 Basel, Switzerland
| | - Alexander Schmidt
- Proteomics Core Facility, Biozentrum, University of Basel , 4056 Basel, Switzerland
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Helicobacter pylori adaptation in vivo in response to a high-salt diet. Infect Immun 2015; 83:4871-83. [PMID: 26438795 DOI: 10.1128/iai.00918-15] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 09/30/2015] [Indexed: 12/21/2022] Open
Abstract
Helicobacter pylori exhibits a high level of intraspecies genetic diversity. In this study, we investigated whether the diversification of H. pylori is influenced by the composition of the diet. Specifically, we investigated the effect of a high-salt diet (a known risk factor for gastric adenocarcinoma) on H. pylori diversification within a host. We analyzed H. pylori strains isolated from Mongolian gerbils fed either a high-salt diet or a regular diet for 4 months by proteomic and whole-genome sequencing methods. Compared to the input strain and output strains from animals fed a regular diet, the output strains from animals fed a high-salt diet produced higher levels of proteins involved in iron acquisition and oxidative-stress resistance. Several of these changes were attributable to a nonsynonymous mutation in fur (fur-R88H). Further experiments indicated that this mutation conferred increased resistance to high-salt conditions and oxidative stress. We propose a model in which a high-salt diet leads to high levels of gastric inflammation and associated oxidative stress in H. pylori-infected animals and that these conditions, along with the high intraluminal concentrations of sodium chloride, lead to selection of H. pylori strains that are most fit for growth in this environment.
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