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Johnston EL, Guy-Von Stieglitz S, Zavan L, Cross J, Greening DW, Hill AF, Kaparakis-Liaskos M. The effect of altered pH growth conditions on the production, composition, and proteomes of Helicobacter pylori outer membrane vesicles. Proteomics 2024; 24:e2300269. [PMID: 37991474 DOI: 10.1002/pmic.202300269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 10/03/2023] [Accepted: 10/16/2023] [Indexed: 11/23/2023]
Abstract
Gram-negative bacteria release outer membrane vesicles (OMVs) that contain cargo derived from their parent bacteria. Helicobacter pylori is a Gram-negative human pathogen that produces urease to increase the pH of the surrounding environment to facilitate colonization of the gastric mucosa. However, the effect of acidic growth conditions on the production and composition of H. pylori OMVs is unknown. In this study, we examined the production, composition, and proteome of H. pylori OMVs produced during acidic and neutral pH growth conditions. H. pylori growth in acidic conditions reduced the quantity and size of OMVs produced. Additionally, OMVs produced during acidic growth conditions had increased protein, DNA, and RNA cargo compared to OMVs produced during neutral conditions. Proteomic analysis comparing the proteomes of OMVs to their parent bacteria demonstrated significant differences in the enrichment of beta-lactamases and outer membrane proteins between bacteria and OMVs, supporting that differing growth conditions impacts OMV composition. We also identified differences in the enrichment of proteins between OMVs produced during different pH growth conditions. Overall, our findings reveal that growth of H. pylori at different pH levels is a factor that alters OMV proteomes, which may affect their subsequent functions.
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Affiliation(s)
- Ella L Johnston
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Bundoora, Australia
- Research Centre for Extracellular Vesicles, La Trobe University, Bundoora, Australia
| | - Sebastian Guy-Von Stieglitz
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Bundoora, Australia
- Research Centre for Extracellular Vesicles, La Trobe University, Bundoora, Australia
| | - Lauren Zavan
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Bundoora, Australia
- Research Centre for Extracellular Vesicles, La Trobe University, Bundoora, Australia
| | - Jonathon Cross
- Baker Heart and Diabetes Institute, Melbourne, Australia
- Baker Department of Cardiometabolic Health, University of Melbourne, Melbourne, Australia
| | - David W Greening
- Research Centre for Extracellular Vesicles, La Trobe University, Bundoora, Australia
- Baker Heart and Diabetes Institute, Melbourne, Australia
- Baker Department of Cardiometabolic Health, University of Melbourne, Melbourne, Australia
| | - Andrew F Hill
- Research Centre for Extracellular Vesicles, La Trobe University, Bundoora, Australia
- Department of Biochemistry and Chemistry, School of Agriculture, Biomedicine and Environment, La Trobe University, Bundoora, Australia
- Institute for Health and Sport, Victoria University, Melbourne, Victoria, Australia
| | - Maria Kaparakis-Liaskos
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Bundoora, Australia
- Research Centre for Extracellular Vesicles, La Trobe University, Bundoora, Australia
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2
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Patel L, Ailloud F, Suerbaum S, Josenhans C. Single-base resolution quantitative genome methylation analysis in the model bacterium Helicobacter pylori by enzymatic methyl sequencing (EM-Seq) reveals influence of strain, growth phase, and methyl homeostasis. BMC Biol 2024; 22:125. [PMID: 38807090 PMCID: PMC11134628 DOI: 10.1186/s12915-024-01921-1] [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: 01/14/2024] [Accepted: 05/16/2024] [Indexed: 05/30/2024] Open
Abstract
BACKGROUND Bacterial epigenetics is a rapidly expanding research field. DNA methylation by diverse bacterial methyltransferases (MTases) contributes to genomic integrity and replication, and many recent studies extended MTase function also to global transcript regulation and phenotypic variation. Helicobacter pylori is currently one of those bacterial species which possess the highest number and the most variably expressed set of DNA MTases. Next-generation sequencing technologies can directly detect DNA base methylation. However, they still have limitations in their quantitative and qualitative performance, in particular for cytosine methylation. RESULTS As a complementing approach, we used enzymatic methyl sequencing (EM-Seq), a technology recently established that has not yet been fully evaluated for bacteria. Thereby, we assessed quantitatively, at single-base resolution, whole genome cytosine methylation for all methylated cytosine motifs in two different H. pylori strains and isogenic MTase mutants. EM-Seq reliably detected both m5C and m4C methylation. We demonstrated that three different active cytosine MTases in H. pylori provide considerably different levels of average genome-wide single-base methylation, in contrast to isogenic mutants which completely lost specific motif methylation. We found that strain identity and changed environmental conditions, such as growth phase and interference with methyl donor homeostasis, significantly influenced quantitative global and local genome-wide methylation in H. pylori at specific motifs. We also identified significantly hyper- or hypo-methylated cytosines, partially linked to overlapping MTase target motifs. Notably, we revealed differentially methylated cytosines in genome-wide coding regions under conditions of methionine depletion, which can be linked to transcript regulation. CONCLUSIONS This study offers new knowledge on H. pylori global and local genome-wide methylation and establishes EM-Seq for quantitative single-site resolution analyses of bacterial cytosine methylation.
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Affiliation(s)
- Lubna Patel
- Max von Pettenkofer Institute, Chair for Medical Microbiology, Faculty of Medicine, LMU Munich, Pettenkoferstr. 9a, 80336, Munich, Germany
| | - Florent Ailloud
- Max von Pettenkofer Institute, Chair for Medical Microbiology, Faculty of Medicine, LMU Munich, Pettenkoferstr. 9a, 80336, Munich, Germany
| | - Sebastian Suerbaum
- Max von Pettenkofer Institute, Chair for Medical Microbiology, Faculty of Medicine, LMU Munich, Pettenkoferstr. 9a, 80336, Munich, Germany
| | - Christine Josenhans
- Max von Pettenkofer Institute, Chair for Medical Microbiology, Faculty of Medicine, LMU Munich, Pettenkoferstr. 9a, 80336, Munich, Germany.
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3
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Sedarat Z, Taylor-Robinson AW. Helicobacter pylori Outer Membrane Proteins and Virulence Factors: Potential Targets for Novel Therapies and Vaccines. Pathogens 2024; 13:392. [PMID: 38787244 PMCID: PMC11124246 DOI: 10.3390/pathogens13050392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 04/12/2024] [Accepted: 05/07/2024] [Indexed: 05/25/2024] Open
Abstract
Helicobacter pylori is a gastric oncopathogen that infects over half of the world's human population. It is a Gram-negative, microaerophilic, helix-shaped bacterium that is equipped with flagella, which provide high motility. Colonization of the stomach is asymptomatic in up to 90% of people but is a recognized risk factor for developing various gastric disorders such as gastric ulcers, gastric cancer and gastritis. Invasion of the human stomach occurs via numerous virulence factors such as CagA and VacA. Similarly, outer membrane proteins (OMPs) play an important role in H. pylori pathogenicity as a means to adapt to the epithelial environment and thereby facilitate infection. While some OMPs are porins, others are adhesins. The epithelial cell receptors SabA, BabA, AlpA, OipA, HopQ and HopZ have been extensively researched to evaluate their epidemiology, structure, role and genes. Moreover, numerous studies have been performed to seek to understand the complex relationship between these factors and gastric diseases. Associations exist between different H. pylori virulence factors, the co-expression of which appears to boost the pathogenicity of the bacterium. Improved knowledge of OMPs is a major step towards combatting this global disease. Here, we provide a current overview of different H. pylori OMPs and discuss their pathogenicity, epidemiology and correlation with various gastric diseases.
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Affiliation(s)
- Zahra Sedarat
- Cellular & Molecular Research Centre, Shahrekord University of Medical Sciences, Shahrekord 8813833435, Iran;
| | - Andrew W. Taylor-Robinson
- College of Health Sciences, VinUniversity, Gia Lam District, Hanoi 67000, Vietnam
- Center for Global Health, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 1904, USA
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4
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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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5
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Ng HK, Chua KH, Kee BP, Chuah KH, Por LY, Puah SM. Genetic variations of penicillin-binding protein 1A: insights into the current status of amoxicillin-based regimens for Helicobacter pylori eradication in Malaysia. J Med Microbiol 2024; 73. [PMID: 38712922 DOI: 10.1099/jmm.0.001832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2024] Open
Abstract
Introduction. Resistance towards amoxicillin in Helicobacter pylori causes significant therapeutic impasse in healthcare settings worldwide. In Malaysia, the standard H. pylori treatment regimen includes a 14-day course of high-dose proton-pump inhibitor (rabeprazole, 20 mg) with amoxicillin (1000 mg) dual therapy.Hypothesis/Gap Statement. The high eradication rate with amoxicillin-based treatment could be attributed to the primary resistance rates of amoxicillin being relatively low at 0%, however, a low rate of secondary resistance has been documented in Malaysia recently.Aim. This study aims to investigate the amino acid mutations and related genetic variants in PBP1A of H. pylori, correlating with amoxicillin resistance in the Malaysian population.Methodology. The full-length pbp1A gene was amplified via PCR from 50 genomic DNA extracted from gastric biopsy samples of H. pylori-positive treatment-naïve Malaysian patients. The sequences were then compared with reference H. pylori strain ATCC 26695 for mutation and variant detection. A phylogenetic analysis of 50 sequences along with 43 additional sequences from the NCBI database was performed. These additional sequences included both amoxicillin-resistant strains (n=20) and amoxicillin-sensitive strains (n=23).Results. There was a total of 21 variants of amino acids, with three of them located in or near the PBP-motif (SKN402-404). The percentages of these three variants are as follows: K403X, 2%; S405I, 2% and E406K, 16%. Based on the genetic markers identified, the resistance rate for amoxicillin in our sample remained at 0%. The phylogenetic examination suggested that H. pylori might exhibit unique conserved pbp1A sequences within the Malaysian context.Conclusions. Overall, the molecular analysis of PBP1A supported the therapeutic superiority of amoxicillin-based regimens. Therefore, it is crucial to continue monitoring the amoxicillin resistance background of H. pylori with a larger sample size to ensure the sustained effectiveness of amoxicillin-based treatments in Malaysia.
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Affiliation(s)
- Heng Kang Ng
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
| | - Boon Pin Kee
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kee Huat Chuah
- Department of Medicine, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
| | - Lip Yee Por
- Department of Computer System and Technology, Faculty of Computer Science and Information Technology, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
| | - Suat Moi Puah
- Department of Biomedical Science, Faculty of Medicine, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
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6
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Sagoo J, Abedrabbo S, Liu X, Ottemann KM. Helicobacter pylori cheV1 mutants recover semisolid agar migration due to loss of a previously uncharacterized Type IV filament membrane alignment complex homolog. J Bacteriol 2024; 206:e0040623. [PMID: 38446058 PMCID: PMC11025336 DOI: 10.1128/jb.00406-23] [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: 12/04/2023] [Accepted: 02/21/2024] [Indexed: 03/07/2024] Open
Abstract
The bacterial chemotaxis system is a well-understood signaling pathway that promotes bacterial success. Chemotaxis systems comprise chemoreceptors and the CheA kinase, linked by CheW or CheV scaffold proteins. Scaffold proteins provide connections between chemoreceptors and CheA and also between chemoreceptors to create macromolecular arrays. Chemotaxis is required for host colonization by many microbes, including the stomach pathogen Helicobacter pylori. This bacterium builds chemoreceptor-CheA contacts with two distinct scaffold proteins, CheW and CheV1. H. pylori cheW or cheV1 deletion mutants both lose chemoreceptor array formation, but show differing semisolid agar chemotaxis assay behaviors: ∆cheW mutants exhibit total migration failure, whereas ∆cheV1::cat mutants display a 50% reduction. On investigating these varied responses, we found that both mutants initially struggle with migration. However, over time, ∆cheV1::cat mutants develop a stable, enhanced migration capability, termed "migration-able" (Mig+). Whole-genome sequencing analysis of four distinct ∆cheV1::cat Mig+ strains identified single-nucleotide polymorphisms (SNPs) in hpg27_252 (hp0273) that were predicted to truncate the encoded protein. Computational analysis of the hpg27_252-encoded protein revealed it encoded a hypothetical protein that was a remote homolog of the PilO Type IV filament membrane alignment complex protein. Although H. pylori lacks Type IV filaments, our analysis showed it retains an operon of genes for homologs of PilO, PilN, and PilM. Deleting hpg27_252 in the ∆cheV1::cat or wild type strain resulted in enhanced migration in semisolid agar. Our study thus reveals that while cheV1 mutants initially have significant migration defects, they can recover the migration ability through genetic suppressors, highlighting a complex regulatory mechanism in bacterial migration. IMPORTANCE Chemotactic motility, present in over half of bacteria, depends on chemotaxis signaling systems comprising receptors, kinases, and scaffold proteins. In Helicobacter pylori, a stomach pathogen, chemotaxis is crucial for colonization, with CheV1 and CheW as key scaffold proteins. While both scaffolds are essential for building chemoreceptor complexes, their roles vary in other assays. Our research reexamines cheV1 mutants' behavior in semisolid agar, a standard chemotaxis test. Initially, cheV1 mutants exhibited defects similar to those of cheW mutants, but they evolved genetic suppressors that enhanced migration. These suppressors involve mutations in a previously uncharacterized gene, unknown in motility behavior. Our findings highlight the significant chemotaxis defects in cheV1 mutants and identify new elements influencing bacterial motility.
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Affiliation(s)
- Jashwin Sagoo
- Department of Microbiology and Environmental Toxicology, UC Santa Cruz, Santa Cruz, California, USA
| | - Samar Abedrabbo
- Department of Microbiology and Environmental Toxicology, UC Santa Cruz, Santa Cruz, California, USA
| | - Xiaolin Liu
- Department of Microbiology and Environmental Toxicology, UC Santa Cruz, Santa Cruz, California, USA
| | - Karen M. Ottemann
- Department of Microbiology and Environmental Toxicology, UC Santa Cruz, Santa Cruz, California, USA
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7
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Collins J, Osheroff N. Gyrase and Topoisomerase IV: Recycling Old Targets for New Antibacterials to Combat Fluoroquinolone Resistance. ACS Infect Dis 2024; 10:1097-1115. [PMID: 38564341 PMCID: PMC11019561 DOI: 10.1021/acsinfecdis.4c00128] [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: 02/16/2024] [Revised: 03/14/2024] [Accepted: 03/18/2024] [Indexed: 04/04/2024]
Abstract
Beyond their requisite functions in many critical DNA processes, the bacterial type II topoisomerases, gyrase and topoisomerase IV, are the targets of fluoroquinolone antibacterials. These drugs act by stabilizing gyrase/topoisomerase IV-generated DNA strand breaks and by robbing the cell of the catalytic activities of these essential enzymes. Since their clinical approval in the mid-1980s, fluoroquinolones have been used to treat a broad spectrum of infectious diseases and are listed among the five "highest priority" critically important antimicrobial classes by the World Health Organization. Unfortunately, the widespread use of fluoroquinolones has been accompanied by a rise in target-mediated resistance caused by specific mutations in gyrase and topoisomerase IV, which has curtailed the medical efficacy of this drug class. As a result, efforts are underway to identify novel antibacterials that target the bacterial type II topoisomerases. Several new classes of gyrase/topoisomerase IV-targeted antibacterials have emerged, including novel bacterial topoisomerase inhibitors, Mycobacterium tuberculosis gyrase inhibitors, triazaacenaphthylenes, spiropyrimidinetriones, and thiophenes. Phase III clinical trials that utilized two members of these classes, gepotidacin (triazaacenaphthylene) and zoliflodacin (spiropyrimidinetrione), have been completed with positive outcomes, underscoring the potential of these compounds to become the first new classes of antibacterials introduced into the clinic in decades. Because gyrase and topoisomerase IV are validated targets for established and emerging antibacterials, this review will describe the catalytic mechanism and cellular activities of the bacterial type II topoisomerases, their interactions with fluoroquinolones, the mechanism of target-mediated fluoroquinolone resistance, and the actions of novel antibacterials against wild-type and fluoroquinolone-resistant gyrase and topoisomerase IV.
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Affiliation(s)
- Jessica
A. Collins
- Department
of Biochemistry, Vanderbilt University School
of Medicine, Nashville, Tennessee 37232, United States
| | - Neil Osheroff
- Department
of Biochemistry, Vanderbilt University School
of Medicine, Nashville, Tennessee 37232, United States
- Department
of Medicine (Hematology/Oncology), Vanderbilt
University School of Medicine, Nashville, Tennessee 37232, United States
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8
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Fonseca D, Alves PM, Neto E, Custódio B, Guimarães S, Moura D, Annis F, Martins M, Gomes A, Teixeira C, Gomes P, Pereira RF, Freitas P, Parreira P, Martins MCL. One-Pot Microfluidics to Engineer Chitosan Nanoparticles Conjugated with Antimicrobial Peptides Using "Photoclick" Chemistry: Validation Using the Gastric Bacterium Helicobacter pylori. ACS APPLIED MATERIALS & INTERFACES 2024; 16:14533-14547. [PMID: 38482690 PMCID: PMC10982938 DOI: 10.1021/acsami.3c18772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 02/27/2024] [Accepted: 02/29/2024] [Indexed: 04/04/2024]
Abstract
Surface bioconjugation of antimicrobial peptides (AMP) onto nanoparticles (AMP-NP) is a complex, multistep, and time-consuming task. Herein, a microfluidic system for the one-pot production of AMP-NP was developed. Norbornene-modified chitosan was used for NP production (NorChit-NP), and thiolated-AMP was grafted on their surface via thiol-norbornene "photoclick" chemistry over exposure of two parallel UV LEDs. The MSI-78A was the AMP selected due to its high activity against a high priority (level 2) antibiotic-resistant gastric pathogen: Helicobacter pylori (H. pylori). AMP-NP (113 ± 43 nm; zeta potential 14.3 ± 7 mV) were stable in gastric settings without a cross-linker (up to 5 days in pH 1.2) and bactericidal against two highly pathogenic H. pylori strains (1011 NP/mL with 96 μg/mL MSI-78A). Eradication was faster for H. pylori 26695 (30 min) than for H. pylori J99 (24 h), which was explained by the lower minimum bactericidal concentration of soluble MSI-78A for H. pylori 26695 (32 μg/mL) than for H. pylori J99 (128 μg/mL). AMP-NP was bactericidal by inducing H. pylori cell membrane alterations, intracellular reorganization, generation of extracellular vesicles, and leakage of cytoplasmic contents (transmission electron microscopy). Moreover, NP were not cytotoxic against two gastric cell lines (AGS and MKN74, ATCC) at bactericidal concentrations. Overall, the designed microfluidic setup is a greener, simpler, and faster approach than the conventional methods to obtain AMP-NP. This technology can be further explored for the bioconjugation of other thiolated-compounds.
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Affiliation(s)
- Diana
R. Fonseca
- i3S
− Instituto de Investigação e Inovação
em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal
- Instituto
Nacional de Engenharia Biomédica, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal
- Faculdade
de Engenharia, Departamento de Engenharia Metalúrgica e de
Materiais, Universidade do Porto, R. Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Pedro M. Alves
- i3S
− Instituto de Investigação e Inovação
em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal
- Instituto
Nacional de Engenharia Biomédica, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal
- Faculdade
de Engenharia, Departamento de Engenharia Metalúrgica e de
Materiais, Universidade do Porto, R. Dr. Roberto Frias, 4200-465 Porto, Portugal
- LAQV-REQUIMTE,
Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 685, 4169-007 Porto, Portugal
| | - Estrela Neto
- i3S
− Instituto de Investigação e Inovação
em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal
- Instituto
Nacional de Engenharia Biomédica, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Beatriz Custódio
- i3S
− Instituto de Investigação e Inovação
em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal
- Instituto
Nacional de Engenharia Biomédica, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal
- ICBAS−Instituto
de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 4050-313 Porto, Portugal
| | - Sofia Guimarães
- i3S
− Instituto de Investigação e Inovação
em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal
- Instituto
Nacional de Engenharia Biomédica, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Duarte Moura
- i3S
− Instituto de Investigação e Inovação
em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal
- Instituto
Nacional de Engenharia Biomédica, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal
- Faculdade
de Engenharia, Departamento de Engenharia Metalúrgica e de
Materiais, Universidade do Porto, R. Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Francesca Annis
- i3S
− Instituto de Investigação e Inovação
em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal
- Instituto
Nacional de Engenharia Biomédica, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Marco Martins
- INL, International
Iberian Nanotechnology Laboratory, Av. Mte. José Veiga s/n, 4715-330 Braga, Portugal
| | - Ana Gomes
- LAQV-REQUIMTE,
Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 685, 4169-007 Porto, Portugal
| | - Cátia Teixeira
- LAQV-REQUIMTE,
Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 685, 4169-007 Porto, Portugal
| | - Paula Gomes
- LAQV-REQUIMTE,
Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre 685, 4169-007 Porto, Portugal
| | - Rúben F. Pereira
- i3S
− Instituto de Investigação e Inovação
em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal
- Instituto
Nacional de Engenharia Biomédica, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal
- ICBAS−Instituto
de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 4050-313 Porto, Portugal
| | - Paulo Freitas
- INL, International
Iberian Nanotechnology Laboratory, Av. Mte. José Veiga s/n, 4715-330 Braga, Portugal
- INESC-MN,
INESC Microsystems and Nanotechnologies, Rua Alves Redol 9, 1000-029 Lisboa, Portugal
| | - Paula Parreira
- i3S
− Instituto de Investigação e Inovação
em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal
- Instituto
Nacional de Engenharia Biomédica, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal
| | - M. Cristina L. Martins
- i3S
− Instituto de Investigação e Inovação
em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal
- Instituto
Nacional de Engenharia Biomédica, Universidade do Porto, R. Alfredo Allen 208, 4200-135 Porto, Portugal
- ICBAS−Instituto
de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 4050-313 Porto, Portugal
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9
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Martini C, Araba V, Beniani M, Armoa Ortiz P, Simmons M, Chalbi M, Mellouk A, El Bakkouri M, Calmettes C. Unraveling the crystal structure of the HpaA adhesin: insights into cell adhesion function and epitope localization of a Helicobacter pylori vaccine candidate. mBio 2024; 15:e0295223. [PMID: 38376163 PMCID: PMC10936181 DOI: 10.1128/mbio.02952-23] [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: 10/30/2023] [Accepted: 01/26/2024] [Indexed: 02/21/2024] Open
Abstract
Helicobacter pylori is a bacterium that exhibits strict host restriction to humans and non-human primates, and the bacterium is widely acknowledged as a significant etiological factor in the development of chronic gastritis, peptic ulcers, and gastric cancers. The pathogenic potential of this organism lies in its adeptness at colonizing the gastric mucosa, which is facilitated by a diverse repertoire of virulence factors, including adhesins that promote the attachment of the bacteria to the gastric epithelium. Among these adhesins, HpaA stands out due to its conserved nature and pivotal role in establishing H. pylori colonization. Moreover, this lipoprotein holds promise as an antigen for the development of effective H. pylori vaccines, thus attracting considerable attention for in-depth investigations into its molecular function and identification of binding determinants. Here, we present the elucidation of the crystallographic structure of HpaA at 2.9 Å resolution. The folding adopts an elongated protein shape, which is distinctive to the Helicobacteraceae family, and features an apical domain extension that plays a critical role in the cell-adhesion activity on gastric epithelial cells. Our study also demonstrates the ability of HpaA to induce TNF-α expression in macrophages, highlighting a novel role as an immunoregulatory effector promoting the pro-inflammatory response in vitro. These findings not only contribute to a deeper comprehension of the multifaceted role of HpaA in H. pylori pathogenesis but also establish a fundamental basis for the design and development of structure-based derivatives, aimed at enhancing the efficacy of H. pylori vaccines. IMPORTANCE Helicobacter pylori is a bacterium that can cause chronic gastritis, peptic ulcers, and gastric cancers. The bacterium adheres to the lining of the stomach using proteins called adhesins. One of these proteins, HpaA, is particularly important for H. pylori colonization and is considered a promising vaccine candidate against H. pylori infections. In this work, we determined the atomic structure of HpaA, identifying a characteristic protein fold to the Helicobacter family and delineating specific amino acids that are crucial to support the attachment to the gastric cells. Additionally, we discovered that HpaA can trigger the production of TNF-α, a proinflammatory molecule, in macrophages. These findings provide valuable insights into how H. pylori causes disease and suggest that HpaA has a dual role in both attachment and immune activation. This knowledge could contribute to the development of improved vaccine strategies for preventing H. pylori infections.
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Affiliation(s)
- Cyrielle Martini
- Institut National de la Recherche Scientifique (INRS), Centre Armand Frappier Santé Biotechnologie, Institut Pasteur International Network, Laval, Québec, Canada
| | - Victoria Araba
- Institut National de la Recherche Scientifique (INRS), Centre Armand Frappier Santé Biotechnologie, Institut Pasteur International Network, Laval, Québec, Canada
| | - Meriem Beniani
- Institut National de la Recherche Scientifique (INRS), Centre Armand Frappier Santé Biotechnologie, Institut Pasteur International Network, Laval, Québec, Canada
| | - Paula Armoa Ortiz
- Institut National de la Recherche Scientifique (INRS), Centre Armand Frappier Santé Biotechnologie, Institut Pasteur International Network, Laval, Québec, Canada
| | - Mimi Simmons
- National Research Council of Canada (NRC), Human Health Therapeutics Research Center, Montréal, Québec, Canada
| | - Mariem Chalbi
- Institut National de la Recherche Scientifique (INRS), Centre Armand Frappier Santé Biotechnologie, Institut Pasteur International Network, Laval, Québec, Canada
| | - Abdelkader Mellouk
- Institut National de la Recherche Scientifique (INRS), Centre Armand Frappier Santé Biotechnologie, Institut Pasteur International Network, Laval, Québec, Canada
| | - Majida El Bakkouri
- National Research Council of Canada (NRC), Human Health Therapeutics Research Center, Montréal, Québec, Canada
| | - Charles Calmettes
- Institut National de la Recherche Scientifique (INRS), Centre Armand Frappier Santé Biotechnologie, Institut Pasteur International Network, Laval, Québec, Canada
- PROTEO, the Quebec Network for Research on Protein Function, Structure, and Engineering, Québec city, Québec, Canada
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10
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Dhindwal P, Boniecki MT, Moore SA. Helicobacter pylori FlgN binds its substrate FlgK and the flagellum ATPase FliI in a similar manner observed for the FliT chaperone. Protein Sci 2024; 33:e4882. [PMID: 38151822 PMCID: PMC10804663 DOI: 10.1002/pro.4882] [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: 07/28/2023] [Revised: 12/19/2023] [Accepted: 12/20/2023] [Indexed: 12/29/2023]
Abstract
In bacterial flagellum biogenesis, secretion of the hook-filament junction proteins FlgK and FlgL and completion of the flagellum requires the FlgN chaperone. Similarly, the related FliT chaperone is necessary for the secretion of the filament cap protein FliD and binds the flagellar export gate protein FlhA and the flagellum ATPase FliI. FlgN and FliT require FliJ for effective substrate secretion. In Helicobacter pylori, neither FlgN, FliT, nor FliJ have been annotated. We demonstrate that the genome location of HP1120 is identical to that of flgN in other flagellated bacteria and that HP1120 is the homolog of Campylobacter jejuni FlgN. A modeled HP1120 structure contains three α-helices and resembles the FliT chaperone, sharing a similar substrate-binding pocket. Using pulldowns and thermophoresis, we show that both HP1120 and a HP1120Δ126-144 deletion mutant bind to FlgK with nanomolar affinity, but not to the filament cap protein FliD, confirming that HP1120 is FlgN. Based on size-exclusion chromatography and multi-angle light scattering, H. pylori FlgN binds to FlgK with 1:1 stoichiometry. Overall structural similarities between FlgN and FliT suggest that substrate recognition on FlgN primarily involves an antiparallel coiled-coil interface between the third helix of FlgN and the C-terminal helix of the substrate. A FlgNΔ126-144 N100A, Y103A, S111I triple mutant targeting this interface significantly impairs the binding of FlgK. Finally, we demonstrate that FlgNΔ126-144 , like FliT, binds with sub-micromolar affinity to the flagellum ATPase FliI or its N-terminal domain. Hence FlgN and FliT likely couple delivery of low-abundance export substrates to the flagellum ATPase FliI.
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Affiliation(s)
- Poonam Dhindwal
- Department of Biochemistry, Microbiology and ImmunologyCollege of Medicine, University of SaskatchewanSaskatoonCanada
| | - Michal T. Boniecki
- Department of Biochemistry, Microbiology and ImmunologyCollege of Medicine, University of SaskatchewanSaskatoonCanada
| | - Stanley A. Moore
- Department of Biochemistry, Microbiology and ImmunologyCollege of Medicine, University of SaskatchewanSaskatoonCanada
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11
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Zimmerman EH, Ramsey EL, Hunter KE, Villadelgado SM, Phillips CM, Shipman RT, Forsyth MH. The Helicobacter pylori methylome is acid-responsive due to regulation by the two-component system ArsRS and the type I DNA methyltransferase HsdM1 (HP0463). J Bacteriol 2024; 206:e0030923. [PMID: 38179929 PMCID: PMC10810217 DOI: 10.1128/jb.00309-23] [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: 09/23/2023] [Accepted: 12/14/2023] [Indexed: 01/06/2024] Open
Abstract
In addition to its role in genome protection, DNA methylation can regulate gene expression. In this study, we characterized the impact of acidity, phase variation, and the ArsRS TCS on the expression of the Type I m6A DNA methyltransferase HsdM1 (HP0463) of Helicobacter pylori 26695 and their subsequent effects on the methylome. Transcription of hsdM1 increases at least fourfold in the absence of the sensory histidine kinase ArsS, the major acid-sensing protein of H. pylori. hsdM1 exists in the phase-variable operon hsdR1-hsdM1. Phase-locking hsdR1 (HP0464), the restriction endonuclease gene, has significant impacts on the transcription of hsdM1. To determine the impacts of methyltransferase transcription patterns on the methylome, we conducted methylome sequencing on samples cultured at pH 7 or pH 5. We found differentially methylated motifs between these growth conditions and that deletions of arsS and/or hsdM1 interfere with the epigenetic acid response. Deletion of arsS leads to altered activity of HsdM1 and multiple other methyltransferases under both pH conditions indicating that the ArsRS TCS, in addition to direct effects on regulon transcription during acid acclimation, may also indirectly impact gene expression via regulation of the methylome. We determined the target motif of HsdM1 (HP0463) to be the complementary bipartite sequence pair 5'-TCAm6AVN6TGY-3' and 3'-AGTN6GAm6ACA-5'. This complex regulation of DNA methyltransferases, and thus differential methylation patterns, may have implications for the decades-long persistent infection by H. pylori. IMPORTANCE This study expands the possibilities for complex, epigenomic regulation in Helicobacter pylori. We demonstrate that the H. pylori methylome is plastic and acid sensitive via the two-component system ArsRS and the DNA methyltransferase HsdM1. The control of a methyltransferase by ArsRS may allow for a layered response to changing acidity. Likely, an early response whereby ArsR~P affects regulon expression, including the methyltransferase hsdM1. Then, a somewhat later effect as the altered methylome, due to altered HsdM1 expression, subsequently alters the expression of other genes involved in acclimation. The intermediate methylation of certain motifs supports the hypothesis that methyltransferases play a regulatory role. Untangling this additional web of regulation could play a key role in understanding H. pylori colonization and persistence.
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Affiliation(s)
| | - Erin L. Ramsey
- Department of Biology, William & Mary, Williamsburg, Virginia, USA
| | | | | | | | - Ryan T. Shipman
- Department of Biology, William & Mary, Williamsburg, Virginia, USA
| | - Mark H. Forsyth
- Department of Biology, William & Mary, Williamsburg, Virginia, USA
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12
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Mitchell SL, Kearns DB, Carlson EE. Penicillin-binding protein redundancy in Bacillus subtilis enables growth during alkaline shock. Appl Environ Microbiol 2024; 90:e0054823. [PMID: 38126750 PMCID: PMC10807460 DOI: 10.1128/aem.00548-23] [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: 04/03/2023] [Accepted: 11/13/2023] [Indexed: 12/23/2023] Open
Abstract
Penicillin-binding proteins (PBPs) play critical roles in cell wall construction, cell shape maintenance, and bacterial replication. Bacteria maintain a diversity of PBPs, indicating that despite their apparent functional redundancy, there is differentiation across the PBP family. Apparently-redundant proteins can be important for enabling an organism to cope with environmental stressors. In this study, we evaluated the consequence of environmental pH on PBP enzymatic activity in Bacillus subtilis. Our data show that a subset of PBPs in B. subtilis change activity levels during alkaline shock and that one PBP isoform is rapidly modified to generate a smaller protein (i.e., PBP1a to PBP1b). Our results indicate that a subset of the PBPs are favored for growth under alkaline conditions, while others are readily dispensable. Indeed, we found that this phenomenon could also be observed in Streptococcus pneumoniae, implying that it may be generalizable across additional bacterial species and further emphasizing the evolutionary benefit of maintaining many, seemingly-redundant periplasmic enzymes.IMPORTANCEMicrobes adapt to ever-changing environments and thrive over a vast range of conditions. While bacterial genomes are relatively small, significant portions encode for "redundant" functions. Apparent redundancy is especially pervasive in bacterial proteins that reside outside of the inner membrane. While conditions within the cytoplasm are carefully controlled, those of the periplasmic space are largely determined by the cell's exterior environment. As a result, proteins within this environmentally exposed region must be capable of functioning under a vast array of conditions, and/or there must be several similar proteins that have evolved to function under a variety of conditions. This study examines the activity of a class of enzymes that is essential in cell wall construction to determine if individual proteins might be adapted for activity under particular growth conditions. Our results indicate that a subset of these proteins are preferred for growth under alkaline conditions, while others are readily dispensable.
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Affiliation(s)
| | - Daniel B. Kearns
- Department of Biology, Indiana University, Bloomington, Indiana, USA
| | - Erin E. Carlson
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota, USA
- Departments of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota, USA
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN, United States
- Department of Pharmacology, University of Minnesota, Minneapolis, MN, United States
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13
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Saberi S, Shans N, Ghaffari S, Esmaeili M, Mohammadi M. The role of CEACAMs versus integrins in Helicobacter pylori CagA translocation: a systematic review. Microbes Infect 2024; 26:105246. [PMID: 37926369 DOI: 10.1016/j.micinf.2023.105246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 10/24/2023] [Accepted: 10/30/2023] [Indexed: 11/07/2023]
Abstract
The delivery of Helicobacter pylori CagA into host cells was long believed to occur through the integrin cell surface receptors. However, the role of CEACAM receptors has recently been highlighted, instead. Here, we have categorized the existing experimental evidence according to whether deletion, upregulation, downregulation, or inhibition of the target ligands (T4SS or HopQ) or receptors (integrins or CEACAMs), result in alterations in CagA phosphorylation, cell elongation, or IL-8 production. According to our analysis, the statistics favor the essence of most of the T4SS constituents and the involvement of HopQ adhesin in all three functions. Concerning the integrin family, the collected data is controversial, but yielding towards it being dispensable or involved in CagA translocation. Yet, regarding cell elongation, more events are showing β1 integrin being involved, than αvβ4 being inhibitory. Concerning IL-8 secretion, again there are more events showing α5, β1 and β6 integrins to be involved, than those showing inhibitory roles for β1, β4 and β6 integrins. Finally, CEACAM 1, 3, and 5 are identified as mostly essential or involved in CagA phosphorylation, whereasCEACAM 4, 7, and 8 are found dispensable and CEACAM6 is under debate. Conversely, CEACAM1, 5 and 6 appear mostly dispensable for cell elongation. Noteworthy is the choice of cell type, bacterial strain, multiplicity and duration of infection, as well as the sensitivity of the detection methods, all of which can affect the variably obtained results.
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Affiliation(s)
- Samaneh Saberi
- HPGC Research Group, Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Nazanin Shans
- HPGC Research Group, Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Saba Ghaffari
- HPGC Research Group, Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Maryam Esmaeili
- HPGC Research Group, Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Marjan Mohammadi
- HPGC Research Group, Department of Medical Biotechnology, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran.
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14
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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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15
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Zhao X, Feng J, Zhang J, Han Z, Hu Y, Shao HH, Li T, Xia J, Lei K, Wang W, Lai F, Lin Y, Liu B, Zhang K, Zhang C, Yang Q, Luo X, Zhang H, Li C, Zhang W, Wu S. Discovery and druggability evaluation of pyrrolamide-type GyrB/ParE inhibitor against drug-resistant bacterial infection. Acta Pharm Sin B 2023; 13:4945-4962. [PMID: 38045053 PMCID: PMC10692473 DOI: 10.1016/j.apsb.2023.08.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 08/07/2023] [Accepted: 08/18/2023] [Indexed: 12/05/2023] Open
Abstract
The bacterial ATP-competitive GyrB/ParE subunits of type II topoisomerase are important anti-bacterial targets to treat super drug-resistant bacterial infections. Herein we discovered novel pyrrolamide-type GyrB/ParE inhibitors based on the structural modifications of the candidate AZD5099 that was withdrawn from the clinical trials due to safety liabilities such as mitochondrial toxicity. The hydroxyisopropyl pyridazine compound 28 had a significant inhibitory effect on Gyrase (GyrB, IC50 = 49 nmol/L) and a modest inhibitory effect on Topo IV (ParE, IC50 = 1.513 μmol/L) of Staphylococcus aureus. It also had significant antibacterial activities on susceptible and resistant Gram-positive bacteria with a minimum inhibitory concentration (MIC) of less than 0.03 μg/mL, which showed a time-dependent bactericidal effect and low frequencies of spontaneous resistance against S. aureus. Compound 28 had better protective effects than the positive control drugs such as DS-2969 (5) and AZD5099 (6) in mouse models of sepsis induced by methicillin-resistant Staphylococcus aureus (MRSA) infection. It also showed better bactericidal activities than clinically used vancomycin in the mouse thigh MRSA infection models. Moreover, compound 28 has much lower mitochondrial toxicity than AZD5099 (6) as well as excellent therapeutic indexes and pharmacokinetic properties. At present, compound 28 has been evaluated as a pre-clinical drug candidate for the treatment of drug-resistant Gram-positive bacterial infection. On the other hand, compound 28 also has good inhibitory activities against stubborn Gram-negative bacteria such as Escherichia coli (MIC = 1 μg/mL), which is comparable with the most potent pyrrolamide-type GyrB/ParE inhibitors reported recently. In addition, the structure-activity relationships of the compounds were also studied.
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Affiliation(s)
| | | | | | - Zunsheng Han
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Yuhua Hu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Hui-Hui Shao
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Tianlei Li
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Jie Xia
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Kangfan Lei
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Weiping Wang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Fangfang Lai
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Yuan Lin
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Bo Liu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Kun Zhang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Chi Zhang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Qingyun Yang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Xinyu Luo
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Hanyilan Zhang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Chuang Li
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Wenxuan Zhang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Song Wu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
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16
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Augustine J, Baksh KA, Prosser RS, Zamble DB. Insights into the Allosteric Response to Acidity by the Helicobacter pylori NikR Transcription Factor. Biochemistry 2023; 62:3265-3275. [PMID: 37917856 DOI: 10.1021/acs.biochem.3c00356] [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: 11/04/2023]
Abstract
Helicobacter pylori NikR (HpNikR) is a nickel-responsive transcription factor that regulates genes involved in nickel homeostasis, which is essential for the survival of this pathogen within the acidic human stomach. HpNikR also responds to drops in pH and regulates genes controlling acid acclimation of the bacteria, independently of nickel. We previously showed that nickel binding biases the conformational ensemble of HpNikR to the more DNA-binding competent states via an allosteric network of residues encompassing the nickel binding sites and the interface between the metal- and DNA-binding domains. Here, we examine how acidity promotes this response using 19F-NMR, mutagenesis, and DNA-binding studies. 19F-NMR revealed that a drop in pH from 7.6 to 6.0 does little to shift the conformational ensemble of HpNikR to the DNA binding-compatible cis conformer. Nevertheless, DNA-binding affinities of apo-HpNikR at pH 6.0 and Ni(II)-HpNikR at pH 7.6 are comparable for the ureA promoter. Histidine residues of the nickel binding sites were shown to be important for pH-dependent DNA binding and thus likely impart positive charge to the protein, initiating long-range electrostatic interactions with DNA that induce DNA complexation. The results point to a different DNA-binding mechanism in response to acidity compared to the conformational selection mechanism in response to nickel and overall provide new insights into the influence of pH on HpNikR activity, which contributes to H. pylori viability.
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Affiliation(s)
- Jerry Augustine
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Karina A Baksh
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Robert Scott Prosser
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Deborah B Zamble
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada
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17
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Botting JM, Tachiyama S, Gibson KH, Liu J, Starai VJ, Hoover TR. FlgV forms a flagellar motor ring that is required for optimal motility of Helicobacter pylori. PLoS One 2023; 18:e0287514. [PMID: 37976320 PMCID: PMC10655999 DOI: 10.1371/journal.pone.0287514] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 06/07/2023] [Indexed: 11/19/2023] Open
Abstract
Flagella-driven motility is essential for Helicobacter pylori to colonize the human stomach, where it causes a variety of diseases, including chronic gastritis, peptic ulcer disease, and gastric cancer. H. pylori has evolved a high-torque-generating flagellar motor that possesses several accessories not found in the archetypical Escherichia coli motor. FlgV was one of the first flagellar accessory proteins identified in Campylobacter jejuni, but its structure and function remain poorly understood. Here, we confirm that deletion of flgV in H. pylori B128 and a highly motile variant of H. pylori G27 (G27M) results in reduced motility in soft agar medium. Comparative analyses of in-situ flagellar motor structures of wild-type, ΔflgV, and a strain expressing FlgV-YFP showed that FlgV forms a ring-like structure closely associated with the junction of two highly conserved flagellar components: the MS and C rings. The results of our studies suggest that the FlgV ring has adapted specifically in Campylobacterota to support the assembly and efficient function of the high-torque-generating motors.
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Affiliation(s)
- Jack M. Botting
- Department of Microbiology, University of Georgia, Athens, Georgia, United States of America
| | - Shoichi Tachiyama
- Microbial Sciences Institute, Yale University, West Haven, Connecticut, United States of America
- Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, Connecticut, United States of America
| | - Katherine H. Gibson
- Department of Microbiology, University of Georgia, Athens, Georgia, United States of America
| | - Jun Liu
- Microbial Sciences Institute, Yale University, West Haven, Connecticut, United States of America
- Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, Connecticut, United States of America
| | - Vincent J. Starai
- Department of Microbiology, University of Georgia, Athens, Georgia, United States of America
| | - Timothy R. Hoover
- Department of Microbiology, University of Georgia, Athens, Georgia, United States of America
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18
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Tran SC, McClain MS, Cover TL. Role of the CagY antenna projection in Helicobacter pylori Cag type IV secretion system activity. Infect Immun 2023; 91:e0015023. [PMID: 37638724 PMCID: PMC10501215 DOI: 10.1128/iai.00150-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 07/07/2023] [Indexed: 08/29/2023] Open
Abstract
Helicobacter pylori strains containing the cag pathogenicity island (PAI) are associated with the development of gastric adenocarcinoma and peptic ulcer disease. The cag PAI encodes a secreted effector protein (CagA) and a type IV secretion system (Cag T4SS). Cag T4SS activity is required for the delivery of CagA and non-protein substrates into host cells. The Cag T4SS outer membrane core complex (OMCC) contains a channel-like domain formed by helix-loop-helix elements (antenna projections, AP) from 14 copies of the CagY protein (a VirB10 ortholog). Similar VirB10 antenna regions are present in T4SS OMCCs from multiple bacterial species and are predicted to span the outer membrane. In this study, we investigated the role of the CagY antenna region in Cag T4SS OMCC assembly and Cag T4SS function. An H. pylori mutant strain with deletion of the entire CagY AP (∆AP) retained the capacity to produce CagY and assemble an OMCC, but it lacked T4SS activity (CagA translocation and IL-8 induction in AGS gastric epithelial cells). In contrast, a mutant strain with Gly-Ser substitutions in the unstructured CagY AP loop retained Cag T4SS activity. Mutants containing CagY AP loops with shortened lengths were defective in CagA translocation and exhibited reduced IL-8-inducing activity compared to control strains. These data indicate that the CagY AP region is required for Cag T4SS activity and that Cag T4SS activity can be modulated by altering the length of the CagY AP unstructured loop.
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Affiliation(s)
- Sirena C. Tran
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, 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
| | - Timothy L. Cover
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- 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
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee, USA
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19
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Sharafutdinov I, Tegtmeyer N, Linz B, Rohde M, Vieth M, Tay ACY, Lamichhane B, Tuan VP, Fauzia KA, Sticht H, Yamaoka Y, Marshall BJ, Backert S. A single-nucleotide polymorphism in Helicobacter pylori promotes gastric cancer development. Cell Host Microbe 2023; 31:1345-1358.e6. [PMID: 37490912 DOI: 10.1016/j.chom.2023.06.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 05/23/2023] [Accepted: 06/27/2023] [Indexed: 07/27/2023]
Abstract
Single-nucleotide polymorphisms (SNPs) in various human genes are key factors in carcinogenesis. However, whether SNPs in bacterial pathogens are similarly crucial in cancer development is unknown. Here, we analyzed 1,043 genomes of the stomach pathogen Helicobacter pylori and pinpointed a SNP in the serine protease HtrA (position serine/leucine 171) that significantly correlates with gastric cancer. Our functional studies reveal that the 171S-to-171L mutation triggers HtrA trimer formation and enhances proteolytic activity and cleavage of epithelial junction proteins occludin and tumor-suppressor E-cadherin. 171L-type HtrA, but not 171S-HtrA-possessing H. pylori, inflicts severe epithelial damage, enhances injection of oncoprotein CagA into epithelial cells, increases NF-κB-mediated inflammation and cell proliferation through nuclear accumulation of β-catenin, and promotes host DNA double-strand breaks, collectively triggering malignant changes. These findings highlight the 171S/L HtrA mutation as a unique bacterial cancer-associated SNP and as a potential biomarker for risk predictions in H. pylori infections.
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Affiliation(s)
- Irshad Sharafutdinov
- Division of Microbiology, Department of Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Nicole Tegtmeyer
- Division of Microbiology, Department of Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Bodo Linz
- Division of Microbiology, Department of Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Manfred Rohde
- Central Facility for Microscopy, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany
| | - Michael Vieth
- Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Klinikum Bayreuth, 95445 Bayreuth, Germany
| | - Alfred Chin-Yen Tay
- Helicobacter Research Laboratory, Marshall Centre for Infectious Diseases Research and Training, School of Pathology and Laboratory Medicine, University of Western Australia, 6009 Perth, Australia
| | - Binit Lamichhane
- Helicobacter Research Laboratory, Marshall Centre for Infectious Diseases Research and Training, School of Pathology and Laboratory Medicine, University of Western Australia, 6009 Perth, Australia
| | - Vo Phuoc Tuan
- Department of Endoscopy, Choray Hospital, Ho Chi Minh, Vietnam; Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Yufu, Oita, Japan
| | - Kartika Afrida Fauzia
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Yufu, Oita, Japan; Department of Public Health and Preventive Medicine, Faculty of Medicine, Universitas Airlangga, Surabaya, Indonesia
| | - Heinrich Sticht
- Division of Bioinformatics, Institute of Biochemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Yufu, Oita, Japan; Department of Medicine, Gastroenterology and Hepatology Section, Baylor College of Medicine, Houston, TX 77030, USA
| | - Barry J Marshall
- Helicobacter Research Laboratory, Marshall Centre for Infectious Diseases Research and Training, School of Pathology and Laboratory Medicine, University of Western Australia, 6009 Perth, Australia; University of Western Australia, Marshall Centre, M504, Crawley, WA, Australia; Marshall Laboratory of Biomedical Engineering, School of Biomedical Engineering, Shenzhen University Health Science Center, Shenzhen, China
| | - Steffen Backert
- Division of Microbiology, Department of Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany.
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20
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Katsande PM, Nguyen VD, Nguyen TLP, Nguyen TKC, Mills G, Bailey DMD, Christie G, Hong HA, Cutting SM. Prophylactic immunization to Helicobacter pylori infection using spore vectored vaccines. Helicobacter 2023; 28:e12997. [PMID: 37314018 PMCID: PMC10909515 DOI: 10.1111/hel.12997] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 05/08/2023] [Accepted: 05/23/2023] [Indexed: 06/15/2023]
Abstract
BACKGROUND Helicobacter pylori infection remains a major public health threat leading to gastrointestinal illness and increased risk of gastric cancer. Mostly affecting populations in developing countries no vaccines are yet available and the disease is controlled by antimicrobials which, in turn, are driving the emergence of AMR. MATERIALS AND METHODS We have engineered spores of Bacillus subtilis to display putative H. pylori protective antigens, urease subunit A (UreA) and subunit B (UreB) on the spore surface. Following oral dosing of mice with these spores, we evaluated immunity and colonization in animals challenged with H. pylori. RESULTS Oral immunization with spores expressing either UreA or UreB showed antigen-specific mucosal responses (fecal sIgA) including seroconversion and hyperimmunity. Following challenge, colonization by H. pylori was significantly reduced by up to 1-log. CONCLUSIONS This study demonstrates the utility of bacterial spores for mucosal vaccination to H. pylori infection. The heat stability and robustness of Bacillus spores coupled with their existing use as probiotics make them an attractive solution for either protection against H. pylori infection or potentially for therapy and control of active infection.
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Affiliation(s)
| | - Van Duy Nguyen
- Institute of Biotechnology and EnvironmentNha Trang UniversityNha TrangVietnam
| | | | - Thi Kim Cuc Nguyen
- Institute of Biotechnology and EnvironmentNha Trang UniversityNha TrangVietnam
| | - Gabrielle Mills
- Department of Chemical Engineering & BiotechnologyUniversity of CambridgeCambridgeUK
| | - David M. D. Bailey
- Department of Chemical Engineering & BiotechnologyUniversity of CambridgeCambridgeUK
| | - Graham Christie
- Department of Chemical Engineering & BiotechnologyUniversity of CambridgeCambridgeUK
| | - Huynh Anh Hong
- Department of Biological SciencesRoyal Holloway University of LondonEghamUK
| | - Simon M. Cutting
- Department of Biological SciencesRoyal Holloway University of LondonEghamUK
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21
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Gómez-Garzón C, Payne SM. Divide and conquer: genetics, mechanism, and evolution of the ferrous iron transporter Feo in Helicobacter pylori. Front Microbiol 2023; 14:1219359. [PMID: 37469426 PMCID: PMC10353542 DOI: 10.3389/fmicb.2023.1219359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 06/14/2023] [Indexed: 07/21/2023] Open
Abstract
Introduction Feo is the most widespread and conserved system for ferrous iron uptake in bacteria, and it is important for virulence in several gastrointestinal pathogens. However, its mechanism remains poorly understood. Hitherto, most studies regarding the Feo system were focused on Gammaproteobacterial models, which possess three feo genes (feoA, B, and C) clustered in an operon. We found that the human pathogen Helicobacter pylori possesses a unique arrangement of the feo genes, in which only feoA and feoB are present and encoded in distant loci. In this study, we examined the functional significance of this arrangement. Methods Requirement and regulation of the individual H. pylori feo genes were assessed through in vivo assays and gene expression profiling. The evolutionary history of feo was inferred via phylogenetic reconstruction, and AlphaFold was used for predicting the FeoA-FeoB interaction. Results and Discussion Both feoA and feoB are required for Feo function, and feoB is likely subjected to tight regulation in response to iron and nickel by Fur and NikR, respectively. Also, we established that feoA is encoded in an operon that emerged in the common ancestor of most, but not all, helicobacters, and this resulted in feoA transcription being controlled by two independent promoters. The H. pylori Feo system offers a new model to understand ferrous iron transport in bacterial pathogens.
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Affiliation(s)
- Camilo Gómez-Garzón
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX, United States
| | - Shelley M. Payne
- Department of Molecular Biosciences, University of Texas at Austin, Austin, TX, United States
- John Ring LaMontagne Center for Infectious Disease, The University of Texas at Austin, Austin, TX, United States
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22
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Bugaytsova JA, Piddubnyi A, Tkachenko I, Rakhimova L, Edlund JO, Thorell K, Marcotte H, Lundquist A, Schön K, Lycke N, Suerbaum S, Schulz C, Malfertheiner P, Hansen LM, Solnick JV, Moskalenko R, Hammarström L, Borén T. Vaccination with Helicobacter pylori attachment proteins protects against gastric cancer. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.25.542131. [PMID: 37461695 PMCID: PMC10349987 DOI: 10.1101/2023.05.25.542131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 07/24/2023]
Abstract
Most cases of gastric cancer are caused by chronic Helicobacter pylori infection, but the lack of early onco-diagnostics and a high risk for antibiotic resistance hampers early intervention through eradication of H. pylori infection by antibiotics. We reported on a protective mechanism where H. pylori gastric mucosal attachment can be reduced by natural antibodies that block the binding of its attachment protein BabA. Here we show that challenge infection with H. pylori induced response of such blocking antibodies in both human volunteers and in rhesus macaques, that mucosal vaccination with BabA protein antigen induced blocking antibodies in rhesus macaques, and that vaccination in a mouse model induced blocking antibodies that reduced gastric mucosal inflammation, preserved the gastric juice acidity, and fully protected the mice from gastric cancer caused by H. pylori.
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Affiliation(s)
- Jeanna A. Bugaytsova
- Department Medical Biochemistry and Biophysics, Umeå University, SE90187 Umeå, Sweden
- SUMEYA, The Ukrainian-Swedish Research Center, Sumy State University, 40022 Sumy, Ukraine
| | - Artem Piddubnyi
- Department Medical Biochemistry and Biophysics, Umeå University, SE90187 Umeå, Sweden
- SUMEYA, The Ukrainian-Swedish Research Center, Sumy State University, 40022 Sumy, Ukraine
- Department of Pathology, Medical Institute, Sumy State University, 40007 Sumy, Ukraine
| | - Iryna Tkachenko
- Department Medical Biochemistry and Biophysics, Umeå University, SE90187 Umeå, Sweden
- Department of Public Health, Medical Institute, Sumy State University, 40007 Sumy, Ukraine
| | - Lena Rakhimova
- Department Medical Biochemistry and Biophysics, Umeå University, SE90187 Umeå, Sweden
- Present address: Department of Odontology, Umea University, SE90187 Umeå, Sweden
| | - Johan Olofsson Edlund
- Department Medical Biochemistry and Biophysics, Umeå University, SE90187 Umeå, Sweden
- The Biochemical Imaging Center Umeå (BICU), Umeå University, SE90187 Umeå, Sweden
| | - Kaisa Thorell
- Department of Chemistry and Molecular Biology, University of Gothenburg, SE40530, Gothenburg, Sweden
| | - Harold Marcotte
- Department Medical Biochemistry and Biophysics, Umeå University, SE90187 Umeå, Sweden
- Department of Biosciences and Nutrition, Karolinska Institutet, SE14183, Huddinge, Sweden
| | - Anders Lundquist
- Department of Statistics, USBE, Umeå University, SE90187 Umeå, Sweden
- Umeå Center for Functional Brain Imaging, Umeå University, SE90187 Umeå, Sweden
| | - Karin Schön
- Department of Microbiology & Immunology, University of Gothenburg, Gothenburg, Sweden
| | - Nils Lycke
- Department of Microbiology & Immunology, University of Gothenburg, Gothenburg, Sweden
- Deceased, December 2022
| | - Sebastian Suerbaum
- Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, 30625 Hannover, Germany
- German Center for Infection Research (DZIF), Hannover-Braunschweig Site, 30625 Hannover, Germany
- Max von Pettenkofer Institute of Hygiene and Medical Microbiology, LMU Munich, 80336 Munich, Germany
- German Center for Infection Research (DZIF), Munich Site, 80336 Munich, Germany
| | - Christian Schulz
- Department of Gastroenterology, Hepatology and Infectious Diseases, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
- Department of Medicine II, University Hospital, LMU Munich, Munich, Germany
| | - Peter Malfertheiner
- Department of Gastroenterology, Hepatology and Infectious Diseases, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
- Department of Medicine II, University Hospital, LMU Munich, Munich, Germany
| | - Lori M. Hansen
- Departments of Medicine and Microbiology and Immunology, Center for Immunology and Infectious Disease, University of California Davis, Davis, CA 95616, USA
| | - Jay V. Solnick
- Departments of Medicine and Microbiology and Immunology, Center for Immunology and Infectious Disease, University of California Davis, Davis, CA 95616, USA
- California National Primate Research Center, University of California Davis School of Medicine, Davis, CA 95616, USA
| | - Roman Moskalenko
- SUMEYA, The Ukrainian-Swedish Research Center, Sumy State University, 40022 Sumy, Ukraine
- Department of Pathology, Medical Institute, Sumy State University, 40007 Sumy, Ukraine
| | - Lennart Hammarström
- Department of Biosciences and Nutrition, Karolinska Institutet, SE14183, Huddinge, Sweden
| | - Thomas Borén
- Department Medical Biochemistry and Biophysics, Umeå University, SE90187 Umeå, Sweden
- SUMEYA, The Ukrainian-Swedish Research Center, Sumy State University, 40022 Sumy, Ukraine
- Lead contact
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23
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Alfaray RI, Saruuljavkhlan B, Fauzia KA, Torres RC, Thorell K, Dewi SR, Kryukov KA, Matsumoto T, Akada J, Vilaichone RK, Miftahussurur M, Yamaoka Y. Global Antimicrobial Resistance Gene Study of Helicobacter pylori: Comparison of Detection Tools, ARG and Efflux Pump Gene Analysis, Worldwide Epidemiological Distribution, and Information Related to the Antimicrobial-Resistant Phenotype. Antibiotics (Basel) 2023; 12:1118. [PMID: 37508214 PMCID: PMC10376887 DOI: 10.3390/antibiotics12071118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 06/15/2023] [Accepted: 06/25/2023] [Indexed: 07/30/2023] Open
Abstract
We conducted a global-scale study to identify H. pylori antimicrobial-resistant genes (ARG), address their global distribution, and understand their effect on the antimicrobial resistance (AMR) phenotypes of the clinical isolates. We identified ARG using several well-known tools against extensive bacterial ARG databases, then analyzed their correlation with clinical antibiogram data from dozens of patients across countries. This revealed that combining multiple tools and databases, followed by manual selection of ARG from the annotation results, produces more conclusive results than using a single tool or database alone. After curation, the results showed that H. pylori has 42 ARG against 11 different antibiotic classes (16 genes related to single antibiotic class resistance and 26 genes related to multidrug resistance). Further analysis revealed that H. pylori naturally harbors ARG in the core genome, called the 'Set of ARG commonly found in the Core Genome of H. pylori (ARG-CORE)', while ARG-ACC-the ARG in the accessory genome-are exclusive to particular strains. In addition, we detected 29 genes of potential efflux pump-related AMR that were mostly categorized as ARG-CORE. The ARG distribution appears to be almost similar either by geographical or H. pylori populations perspective; however, some ARG had a unique distribution since they tend to be found only in a particular region or population. Finally, we demonstrated that the presence of ARG may not directly correlate with the sensitive/resistance phenotype of clinical patient isolates but may influence the minimum inhibitory concentration phenotype.
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Affiliation(s)
- Ricky Indra Alfaray
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Oita 879-5593, Japan
- Helicobacter pylori and Microbiota Study Group, Institute of Tropical Disease, Universitas Airlangga, Surabaya 60286, Indonesia
| | - Batsaikhan Saruuljavkhlan
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Oita 879-5593, Japan
| | - Kartika Afrida Fauzia
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Oita 879-5593, Japan
- Helicobacter pylori and Microbiota Study Group, Institute of Tropical Disease, Universitas Airlangga, Surabaya 60286, Indonesia
- Department of Public Health and Preventive Medicine, Faculty of Medicine, Universitas Airlangga, Surabaya 60132, Indonesia
| | - Roberto C Torres
- The Center for Microbes, Development and Health, Key Laboratory of Molecular Virology and Immunology, Institute Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai 200031, China
| | - Kaisa Thorell
- Department of Chemistry and Molecular Biology, Faculty of Science, University of Gothenburg, 405 30 Gothenburg, Sweden
| | - Selva Rosyta Dewi
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Oita 879-5593, Japan
- Helicobacter pylori and Microbiota Study Group, Institute of Tropical Disease, Universitas Airlangga, Surabaya 60286, Indonesia
| | - Kirill A Kryukov
- Biological Networks Laboratory, Department of Informatics, National Institute of Genetics, Shizuoka 411-8540, Japan
| | - Takashi Matsumoto
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Oita 879-5593, Japan
| | - Junko Akada
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Oita 879-5593, Japan
| | - Ratha-Korn Vilaichone
- Gastroenterology Unit, Department of Medicine, Faculty of Medicine, Thammasat University Hospital, Khlong Nueng 12120, Pathumthani, Thailand
- Center of Excellence in Digestive Diseases, Thammasat University, Thailand Science Research and Innovation Fundamental Fund, Bualuang ASEAN Chair Professorship at Thammasat University, Khlong Nueng 12121, Pathumthani, Thailand
- Department of Medicine, Chulabhorn International College of Medicine (CICM), Thammasat University, Khlong Nueng 12121, Pathumthani, Thailand
- Division of Gastroentero-Hepatology, Department of Internal Medicine, Faculty of Medicine, Dr. Soetomo Teaching Hospital, Universitas Airlangga, Surabaya 60286, Indonesia
| | - Muhammad Miftahussurur
- Helicobacter pylori and Microbiota Study Group, Institute of Tropical Disease, Universitas Airlangga, Surabaya 60286, Indonesia
- Division of Gastroentero-Hepatology, Department of Internal Medicine, Faculty of Medicine, Dr. Soetomo Teaching Hospital, Universitas Airlangga, Surabaya 60286, Indonesia
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Faculty of Medicine, Oita University, Oita 879-5593, Japan
- Division of Gastroentero-Hepatology, Department of Internal Medicine, Faculty of Medicine, Dr. Soetomo Teaching Hospital, Universitas Airlangga, Surabaya 60286, Indonesia
- The Research Center for GLOBAL and LOCAL Infectious Diseases (RCGLID), Oita University, Oita 870-1192, Japan
- Department of Medicine, Gastroenterology and Hepatology Section, Baylor College of Medicine, Houston, TX 77030, USA
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24
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Phuc BH, Tuan VP, Binh TT, Tung PH, Tri TD, Dung HDQ, Thuan NPM, Fauzia KA, Tshibangu-Kabamba E, Alfaray RI, Saruuljavkhlan B, Matsumoto T, Akada J, Yamaoka Y. Comparative genomics of two Vietnamese Helicobacter pylori strains, CHC155 from a non-cardia gastric cancer patient and VN1291 from a duodenal ulcer patient. Sci Rep 2023; 13:8869. [PMID: 37258611 DOI: 10.1038/s41598-023-35527-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 05/19/2023] [Indexed: 06/02/2023] Open
Abstract
Helicobacter pylori is involved in the etiology and severity of several gastroduodenal diseases; however, plasticity of the H. pylori genome makes complete genome assembly difficult. We report here the full genomes of H. pylori strains CHC155 and VN1291 isolated from a non-cardia gastric cancer patient and a duodenal ulcer patient, respectively, and their virulence demonstrated by in vitro infection. Whole-genome sequences were obtained by combining long- and short-reads with a hybrid-assembly approach. Both CHC155 and VN1291 genome possessed four kinds of genomic island: a cag pathogenicity island (cagPAI), two type 4 secretion system islands within an integrative and conjugative element (tfs ICE), and prophage. CHC155 and VN1291 carried East Asian-type cagA and vacA s1m1, and outer membrane protein genes, including two copies of oipA. Corresponded to genetic determinants of antibiotic resistance, chromosomal mutations were identified in CHC155 (rdxA, gyrA, and 23S rRNA) and VN1291 (rdxA, 23S rRNA, and pbp1A). In vitro infection of AGS cells by both strains induced the cell scattering phenotype, tyrosine phosphorylation of CagA, and promoted high levels of IL8 secretion, indicating fully intact phenotypes of the cagPAI. Virulence genes in CHC155 and VN1291 genomes are crucial for H. pylori pathogenesis and are risk factors in the development of gastric cancer and duodenal ulcer. Our in vitro studies indicate that the strains CHC155 and VN1291 carry the pathogenic potential.
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Grants
- 21K08010 Ministry of Education, Culture, Sports, Science and Technology, Japan
- 21K07898 Ministry of Education, Culture, Sports, Science and Technology, Japan
- 221S0002 Ministry of Education, Culture, Sports, Science and Technology, Japan
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Affiliation(s)
- Bui Hoang Phuc
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Oita, Japan
- Faculty of Applied Technology, Van Lang University, Ho Chi Minh City, Vietnam
| | - Vo Phuoc Tuan
- Department of Endoscopy, Cho Ray Hospital, Ho Chi Minh City, Vietnam
| | - Tran Thanh Binh
- Department of Endoscopy, Cho Ray Hospital, Ho Chi Minh City, Vietnam
| | - Pham Huu Tung
- Department of Endoscopy, Cho Ray Hospital, Ho Chi Minh City, Vietnam
| | - Tran Dinh Tri
- Department of Endoscopy, Cho Ray Hospital, Ho Chi Minh City, Vietnam
| | - Ho Dang Quy Dung
- Department of Endoscopy, Cho Ray Hospital, Ho Chi Minh City, Vietnam
| | | | - Kartika Afrida Fauzia
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Oita, Japan
- Department of Public Health and Preventive Medicine, Faculty of Medicine, Universitas Airlangga, Surabaya, 60115, Indonesia
- Helicobacter pylori and Microbiota Study Group, Institute of Tropical Disease, Universitas Airlangga, Surabaya, 60115, Indonesia
| | - Evariste Tshibangu-Kabamba
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Oita, Japan
- Department of Parasitology, Graduate School of Medicine, Osaka Metropolitan University, Osaka, Japan
| | - Ricky Indra Alfaray
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Oita, Japan
- Helicobacter pylori and Microbiota Study Group, Institute of Tropical Disease, Universitas Airlangga, Surabaya, 60115, Indonesia
| | - Batsaikhan Saruuljavkhlan
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Oita, Japan
| | - Takashi Matsumoto
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Oita, Japan
| | - Junko Akada
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Oita, Japan
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Oita, Japan.
- Research Center for GLOBAL and LOCAL Infectious Diseases, Oita University, Yufu, Oita, Japan.
- Department of Medicine, Gastroenterology and Hepatology Section, Baylor College of Medicine, Houston, TX, USA.
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25
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Gupta N, Kumar A, Verma VK. Strategies adopted by gastric pathogen Helicobacter pylori for a mature biofilm formation: Antimicrobial peptides as a visionary treatment. Microbiol Res 2023; 273:127417. [PMID: 37267815 DOI: 10.1016/j.micres.2023.127417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 05/15/2023] [Accepted: 05/21/2023] [Indexed: 06/04/2023]
Abstract
Enormous efforts in recent past two decades to eradicate the pathogen that has been prevalent in half of the world's population have been problematic. The biofilm formed by Helicobacter pylori provides resistance towards innate immune cells, various combinatorial antibiotics, and human antimicrobial peptides, despite the fact that these all are potent enough to eradicate it in vitro. Biofilm provides the opportunity to secrete various virulence factors that strengthen the interaction between host and pathogen helping in evading the innate immune system and ultimately leading to persistence. To our knowledge, this review is the first of its kind to explain briefly the journey of H. pylori starting with the chemotaxis, the mechanism for selecting the site for colonization, the stress faced by the pathogen, and various adaptations to evade these stress conditions by forming biofilm and the morphological changes acquired by the pathogen in mature biofilm. Furthermore, we have explained the human GI tract antimicrobial peptides and the reason behind the failure of these AMPs, and how encapsulation of Pexiganan-A(MSI-78A) in a chitosan microsphere increases the efficiency of eradication.
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Affiliation(s)
- Nidhi Gupta
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Marg, New Delhi 110021, India.
| | - Atul Kumar
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Marg, New Delhi 110021, India
| | - Vijay Kumar Verma
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Marg, New Delhi 110021, India.
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Zarzecka U, Tegtmeyer N, Sticht H, Backert S. Trimer stability of Helicobacter pylori HtrA is regulated by a natural mutation in the protease domain. Med Microbiol Immunol 2023:10.1007/s00430-023-00766-9. [PMID: 37183214 DOI: 10.1007/s00430-023-00766-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 04/26/2023] [Indexed: 05/16/2023]
Abstract
The human pathogen Helicobacter pylori is a major risk factor for gastric disease development. Serine protease HtrA is an important bacterial virulence factor that cleaves the cell junction proteins occludin, claudin-8 and E-cadherin, which causes gastric tissue damage. Using casein zymography, we discovered that HtrA trimer stability varies in clinical H. pylori strains. Subsequent sequence analyses revealed that HtrA trimer stability correlated with the presence of leucine or serine residue at position 171. The importance of these amino acids in determining trimer stability was confirmed by leucine-to-serine swapping experiments using isogenic H. pylori mutant strains as well as recombinant HtrA proteins. In addition, this sequence position displays a high sequence variability among various bacterial species, but generally exhibits a preference for hydrophilic amino acids. This natural L/S171 polymorphism in H. pylori may affect the protease activity of HtrA during infection, which could be of clinical importance and may determine gastric disease development.
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Affiliation(s)
- Urszula Zarzecka
- Division of Microbiology, Department of Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
- Department of General and Medical Biochemistry, Faculty of Biology, University of Gdańsk, Gdańsk, Poland
| | - Nicole Tegtmeyer
- Division of Microbiology, Department of Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Heinrich Sticht
- Division of Bioinformatics, Institute of Biochemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Steffen Backert
- Division of Microbiology, Department of Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
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McClain MS, Bryant KN, McDonald WH, Algood HMS, Cover TL. Identification of an Essential LolD-Like Protein in Helicobacter pylori. J Bacteriol 2023; 205:e0005223. [PMID: 36971548 PMCID: PMC10127691 DOI: 10.1128/jb.00052-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 02/24/2023] [Indexed: 03/29/2023] Open
Abstract
The localization of lipoprotein (Lol) system is used by Gram-negative bacteria to export lipoproteins to the outer membrane. Lol proteins and models of how Lol transfers lipoproteins from the inner to the outer membrane have been extensively characterized in the model organism Escherichia coli, but in numerous bacterial species, lipoprotein synthesis and export pathways deviate from the E. coli paradigm. For example, in the human gastric bacterium Helicobacter pylori, a homolog of the E. coli outer membrane component LolB is not found, E. coli LolC and LolE correspond to a single inner membrane component (LolF), and a homolog of the E. coli cytoplasmic ATPase LolD has not been identified. In the present study, we sought to identify a LolD-like protein in H. pylori. We used affinity-purification mass spectrometry to identify interaction partners of the H. pylori ATP-binding cassette (ABC) family permease LolF and identified the ABC family ATP-binding protein HP0179 as its interaction partner. We engineered H. pylori to conditionally express HP0179 and showed that HP0179 and its conserved ATP binding and ATP hydrolysis motifs are essential for H. pylori growth. We then performed affinity purification-mass spectrometry using HP0179 as the bait and identified LolF as its interaction partner. These results indicate that H. pylori HP0179 is a LolD-like protein and provide a more complete understanding of lipoprotein localization processes in H. pylori, a bacterium in which the Lol system deviates from the E. coli paradigm. IMPORTANCE Lipoproteins are critical in Gram-negative-bacteria for cell surface assembly of LPS, insertion of outer membrane proteins, and sensing envelope stress. Lipoproteins also contribute to bacterial pathogenesis. For many of these functions, lipoproteins must localize to the Gram-negative outer membrane. Transporting lipoproteins to the outer membrane involves the Lol sorting pathway. Detailed analyses of the Lol pathway have been performed in the model organism Escherichia coli, but many bacteria utilize altered components or are missing essential components of the E. coli Lol pathway. Identifying a LolD-like protein in Helicobacter pylori is important to better understand the Lol pathway in diverse bacterial classes. This becomes particularly relevant as lipoprotein localization is targeted for antimicrobial development.
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Affiliation(s)
- Mark S. McClain
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection Immunology and Inflammation, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Kaeli N. Bryant
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - W. Hayes McDonald
- Proteomics Laboratory, Mass Spectrometry Research Center, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Holly M. Scott Algood
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection Immunology and Inflammation, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee, USA
| | - Timothy L. Cover
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Vanderbilt Institute for Infection Immunology and Inflammation, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee, USA
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Thai THN, Nguyen HP, Nguyen THY, Nguyen TBH, Nguyen TH, Nguyen TMN, Ha TMT. Genetic diversity of the oipA gene among Helicobacter pylori isolates and clinical outcome in Vietnam. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2023; 112:105438. [PMID: 37105346 DOI: 10.1016/j.meegid.2023.105438] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 04/19/2023] [Accepted: 04/22/2023] [Indexed: 04/29/2023]
Abstract
Outer inflammatory protein A (OipA), which is encoded by the oipA gene, can induce interleukin-8 secretion in gastric epithelial cells. The functional status of the oipA gene is regulated by the slipped-strand mispairing mechanism based on the CT dinucleotide repeat number in the 5' region. This study aimed to investigate the oipA functional status ("on/off") of Helicobacter pylori (H. pylori) and its association with gastroduodenal diseases in southwestern Vietnam. The cross-sectional study was conducted on 173H. pylori isolates from 173 patients with gastroduodenal diseases. Sanger sequencing was used to determine the functional status of oipA. Multivariable logistic regression analysis was performed to identify the association between oipA status and gastroduodenal diseases. The oipA "on" status accounted for 96% of H. pylori isolates. Twenty-five CT repeat patterns of the oipA 5' signal region were observed, five of which were novel CT repeat patterns. The oipA "on" status was found in 100%, 97.8%, and 86.8% of H. pylori isolates from patients with peptic ulcer, precancerous lesions, and chronic gastritis, respectively (p < 0.01). The oipA "on" status was related to gastric precancerous lesions versus chronic gastritis (adjusted OR = 7.39, 95% CI: 1.35-40.59, p = 0.021) and peptic ulcers versus chronic gastritis (adjusted OR = 12.79, 95% CI: 1.19-1760.32, p = 0.033). Our data show a high prevalence of the oipA "on" status, which was associated with precancerous gastric lesions and peptic ulcers. Moreover, genetic diversity in the number and pattern of CT dinucleotide repeat of oipA among Vietnamese H. pylori strains was identified.
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Affiliation(s)
- Thi Hong Nhung Thai
- Department of Internal Medicine, University of Medicine and Pharmacy, Hue University, Hue, Viet Nam; Department of Internal Medicine, Faculty of Medicine, Can Tho University of Medicine and Pharmacy, Can Tho, Viet Nam
| | - Hong Phong Nguyen
- Department of Pathology and Forensic Medicine, Faculty of Medicine, Can Tho University of Medicine and Pharmacy, Can Tho, Viet Nam
| | - Thi Hai Yen Nguyen
- Department of Microbiology, Faculty of Medicine, Can Tho University of Medicine and Pharmacy, Can Tho, Viet Nam
| | - Thi Be Hai Nguyen
- Department of Microbiology, Faculty of Medicine, Can Tho University of Medicine and Pharmacy, Can Tho, Viet Nam
| | - Thai Hoa Nguyen
- Department of Internal Medicine, Faculty of Medicine, Can Tho University of Medicine and Pharmacy, Can Tho, Viet Nam
| | - Thi Mai Ngan Nguyen
- Department of Medical Genetics, University of Medicine and Pharmacy, Hue University, Hue, Viet Nam
| | - Thi Minh Thi Ha
- Department of Medical Genetics, University of Medicine and Pharmacy, Hue University, Hue, Viet Nam; Institute of Biomedicine, University of Medicine and Pharmacy, Hue University, Hue, Viet Nam.
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Xiao S, Zhang L, Wang X, Li W, Wang X. The signal conversion strategy using the lytic transglycosylase Cag4-double nanoporous gold co-catalysis for the rapid screening of drugs against Helicobacter pylori infection. Biosens Bioelectron 2023; 233:115345. [PMID: 37116248 DOI: 10.1016/j.bios.2023.115345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 04/03/2023] [Accepted: 04/21/2023] [Indexed: 04/30/2023]
Abstract
The cag pathogenicity island (cagPAI) is the main virulence factor of gastric carcinoma induced by Helicobacter pylori (H. pylori). The lytic transglycosylase Cag4 is an important component that assists in the translocation of the bacterial oncoprotein CagA and maintains the peptidoglycan cycle. The allosteric regulation of Cag4 has been preliminarily demonstrated to inhibit H. pylori infection. Unfortunately, a rapid screening technology for allosteric regulators of Cag4 has not been established. In this study, a novel Cag4-double nanoporous gold (NPG) biosensor based on enzyme-inorganic co-catalysis was constructed using the heterologously expressed H. pylori 26695 Cag4 as the biological recognition element for screening Cag4 allosteric regulators. The results showed that chitosan or carboxymethyl chitosan was a mixed Cag4 inhibitor combining non-competition with uncompetition. The inhibition constants were Ki' Chitosan = 0.88909 mg/mL and Ki' Carboxymethyl chitosan = 1.13480 mg/mL, respectively. Surprisingly, D-(+)-cellobiose showed the activation effect of Cag4 on E. coli MG1655 cell wall lysis by decreasing the Ka value by 29.7% and increasing the Vmax value by 71.3%. In addition, molecular docking revealed the importance of the polarity of the C2 substituent group with glucose as the main structure in the Cag4 allosteric regulator. This study provides a fast and useful platform for screening potential new drugs based on the Cag4 allosteric regulator.
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Affiliation(s)
- Sa Xiao
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, PR China
| | - Lei Zhang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, PR China
| | - Xiaolei Wang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, PR China
| | - Wenjuan Li
- Key Laboratory for Experimental Teratology of Chinese Ministry of Education, The Shandong Provincial Key Laboratory of Infection and Immunology, Department of Microbiology, School of Basic Medical Sciences, Shandong University, Jinan, 250012, PR China.
| | - Xia Wang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, PR China.
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Dinh T, Dao O, Killivalavan A, Ngo D, Lee KH. Crystal structure of the apurinic/apyrimidinic endonuclease XthA (HP1526 protein) from Helicobacter pylori. Biochem Biophys Res Commun 2023; 663:8-15. [PMID: 37116395 DOI: 10.1016/j.bbrc.2023.04.047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 04/17/2023] [Indexed: 04/30/2023]
Abstract
Helicobacter pylori is a bacterium that causes gastritis, peptic ulcer disease and adenocarcinoma while infecting human stomach. In the stomach H. pylori is under stresses caused by reactive oxygen and nitrogen species from host immune response, which causes oxidative DNA damage. The DNA damage in single base is repaired by base excision repair (BER) and/or nucleotide incision repair (NIR) pathways. H. pylori retains a minimal set of enzymes involved in the BER and NIR pathways. The HP1526 protein is a single apurinic/apyrimidinic (AP) endonuclease homologous to E. coli Xth protein but little is known for its structure up to now. In this study, the structure of the recombinant HP1526 protein from H. pylori (HpXthA) has been determined at a high resolution of 1.84 Å. From the structural analysis the HpXthA was found to belong to the Xth-like AP endonuclease family carrying the common fold of a central bilayer β-sheet flanked by α-helices with a divalent metal ion bound. A Mn2+ ion and a 1,3-butanediol were unusually found and modeled around the active site. Structural and sequence comparisons among the AP endonucleases show well-conserved residues for metal and DNA binding and for catalysis. Interestingly, the presence of a small polar residue Ser201 of the HpXthA commonly found in NIR-proficient AP endonucleases instead of an aspartate residue in NIR-deficient enzymes suggests that the HpXthA retain a nucleotide incision repair activity.
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Affiliation(s)
- Thom Dinh
- Department of Convergence Medical Science (BK21Plus), Gyeongsang National University, Jinju, 52727, Republic of Korea; Department of Microbiology, School of Medicine, Gyeongsang National University, Jinju, 52727, Republic of Korea
| | - Oanh Dao
- Department of Convergence Medical Science (BK21Plus), Gyeongsang National University, Jinju, 52727, Republic of Korea; Department of Microbiology, School of Medicine, Gyeongsang National University, Jinju, 52727, Republic of Korea
| | - Asaithambi Killivalavan
- Department of Convergence Medical Science (BK21Plus), Gyeongsang National University, Jinju, 52727, Republic of Korea; Department of Microbiology, School of Medicine, Gyeongsang National University, Jinju, 52727, Republic of Korea; PMBBRC, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Duong Ngo
- Department of Convergence Medical Science (BK21Plus), Gyeongsang National University, Jinju, 52727, Republic of Korea; Department of Microbiology, School of Medicine, Gyeongsang National University, Jinju, 52727, Republic of Korea
| | - Kon Ho Lee
- Department of Convergence Medical Science (BK21Plus), Gyeongsang National University, Jinju, 52727, Republic of Korea; Department of Microbiology, School of Medicine, Gyeongsang National University, Jinju, 52727, Republic of Korea; PMBBRC, Gyeongsang National University, Jinju, 52828, Republic of Korea; Institue of Health Sciences, Gyeongsang National University, Jinju, 52727, Republic of Korea.
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Kugler T, Taradin G. HELICOBACTER AND HEPATOBILIARY DISEASES: UPDATE 2023. ARQUIVOS DE GASTROENTEROLOGIA 2023; 60:271-281. [PMID: 37556754 DOI: 10.1590/s0004-2803.202302023-15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 04/28/2023] [Indexed: 08/11/2023]
Abstract
•Clinical studies have shown that hepatobiliary diseases of inflammatory and neoplastic origin are associated with Helicobacter infection. •Translocation and the ascending pathway are putative mechanisms for Helicobacter spp to enter the hepatobiliary system. •H. pylori infection has a systemic effect through the activity of pro-inflammatory cytokines, TNF-α, leukotrienes, interferon-β, interferon-γ, and acute phase proteins. •Histopathological confirmation is needed to present that H. pylori eradication prevents or improves hepatobiliary disease progression. Helicobacter Pylori (H. pylori) is one of the main infectious causes of gastroduodenal diseases, however, its role in developing different extragastric diseases has been proven. The possible involvement of H. pylori in the pathogenesis of cardiovascular, metabolic, neurodegenerative, skin, and hepatobiliary diseases is suggested. The bacterium has been found in tissue samples from the liver, biliary tract, and gallstones of animals and humans. However, the role of H. pylori infection in the pathogenesis of liver and biliary diseases has not been finally established. The histopathological confirmation of the positive effect of H. pylori eradication is needed. In addition, there are discussions on the clinical significance of other Helicobacter species. The review presents the data available for and against the involvement of H. pylori in hepatobi-liary disease development and progression.
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Affiliation(s)
- Tatyana Kugler
- Donetsk National Medical University, Faculty of postgraduate education, Department of Therapy, Donetsk Oblast, Ucrânia
| | - Gennady Taradin
- Donetsk National Medical University, Faculty of postgraduate education, Department of Therapy, Donetsk Oblast, Ucrânia
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Suerbaum S, Ailloud F. Genome and population dynamics during chronic infection with Helicobacter pylori. Curr Opin Immunol 2023; 82:102304. [PMID: 36958230 DOI: 10.1016/j.coi.2023.102304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 02/21/2023] [Accepted: 02/22/2023] [Indexed: 03/25/2023]
Abstract
Helicobacter pylori is responsible for one of the most prevalent bacterial infections worldwide. Chronic infection typically leads to chronic active gastritis. Clinical sequelae, including peptic ulcers, mucosa-associated lymphoid tissue lymphoma or, most importantly, gastric adenocarcinoma develop in 10-15% of cases. H. pylori is characterized by extensive inter-strain diversity which is the result of a high mutation rate, recombination, and a large repertoire of restriction-modification systems. This diversity is thought to be a major contributor to H. pylori's persistence and exceptional aptitude to adapt to the gastric environment and evade the immune system. This review covers efforts in the last decade to characterize and understand the multiple layers of H. pylori's diversity in different biological contexts.
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Affiliation(s)
- Sebastian Suerbaum
- Max von Pettenkofer Institute for Hygiene and Medical Microbiology, Medical Faculty, LMU Munich, Pettenkoferstr. 9a, 80336 Munich, Germany; DZIF German Centre for Infection Research, Munich Partner Site, Pettenkoferstr. 9a, 80336 Munich, Germany; German National Reference Centre for Helicobacter pylori, Pettenkoferstr. 9a, 80336 Munich, Germany.
| | - Florent Ailloud
- Max von Pettenkofer Institute for Hygiene and Medical Microbiology, Medical Faculty, LMU Munich, Pettenkoferstr. 9a, 80336 Munich, Germany; DZIF German Centre for Infection Research, Munich Partner Site, Pettenkoferstr. 9a, 80336 Munich, Germany
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Mitchell SL, Kearns DB, Carlson EE. Penicillin-binding protein redundancy in Bacillus subtilis enables growth during alkaline shock. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.20.533529. [PMID: 36993441 PMCID: PMC10055284 DOI: 10.1101/2023.03.20.533529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
Penicillin-binding proteins (PBPs) play critical roles in cell wall construction, cell shape, and bacterial replication. Bacteria maintain a diversity of PBPs, indicating that despite their apparent functional redundancy, there is differentiation across the PBP family. Seemingly redundant proteins can be important for enabling an organism to cope with environmental stressors. We sought to evaluate the consequence of environmental pH on PBP enzymatic activity in Bacillus subtilis. Our data show that a subset of B. subtilis PBPs change activity levels during alkaline shock and that one PBP isoform is rapidly modified to generate a smaller protein (i.e., PBP1a to PBP1b). Our results indicate that a subset of the PBPs are preferred for growth under alkaline conditions, while others are readily dispensable. Indeed, we found that this phenomenon could also be observed in Streptococcus pneumoniae, implying that it may be generalizable across additional bacterial species and further emphasizing the evolutionary benefit of maintaining many, seemingly redundant periplasmic enzymes.
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Affiliation(s)
| | - Daniel B. Kearns
- Department of Biology, Indiana University, Bloomington, Indiana 47405
| | - Erin E. Carlson
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455
- Departments of Medicinal Chemistry, Biochemistry, Molecular Biology and Biophysics, and Pharmacology, University of Minnesota, Minneapolis, Minnesota 55455
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A Positively Selected fur-R88H Mutation Enhances Helicobacter pylori Fitness in a High-Salt Environment and Alters Fur-Dependent Regulation of Gene Expression. Infect Immun 2023; 91:e0042022. [PMID: 36633416 PMCID: PMC9933627 DOI: 10.1128/iai.00420-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Both Helicobacter pylori infection and a high-salt diet are risk factors for gastric cancer. We previously showed that a mutation in fur (encoding the ferric uptake regulator variant Fur-R88H) was positively selected in H. pylori strains isolated from experimentally infected Mongolian gerbils receiving a high-salt diet. In the present study, we report that continuous H. pylori growth in high-salt conditions in vitro also leads to positive selection of the fur-R88H mutation. Competition experiments with strains containing wild-type fur or fur-R88H, each labeled with unique nucleotide barcodes, showed that the fur-R88H mutation enhances H. pylori fitness under high-salt conditions but reduces H. pylori fitness under routine culture conditions. The fitness advantage of the fur-R88H mutant under high-salt conditions was abrogated by the addition of supplemental iron. To test the hypothesis that the fur-R88H mutation alters the regulatory properties of Fur, we compared the transcriptional profiles of strains containing wild-type fur or fur-R88H. Increased transcript levels of fecA2, which encodes a predicted TonB-dependent outer membrane transporter, were detected in the fur-R88H variant compared to those in the strain containing wild-type fur under both high-salt and routine conditions. Competition experiments showed that fecA2 contributes to H. pylori fitness under both high-salt and routine conditions. These results provide new insights into mechanisms by which the fur-R88H mutation confers a selective advantage to H. pylori in high-salt environments.
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Integrative proteomic characterization of adenocarcinoma of esophagogastric junction. Nat Commun 2023; 14:778. [PMID: 36774361 PMCID: PMC9922290 DOI: 10.1038/s41467-023-36462-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 02/02/2023] [Indexed: 02/13/2023] Open
Abstract
The incidence of adenocarcinoma of the esophagogastric junction (AEG) has been rapidly increasing in recent decades, but its molecular alterations and subtypes are still obscure. Here, we conduct proteomics and phosphoproteomics profiling of 103 AEG tumors with paired normal adjacent tissues (NATs), whole exome sequencing of 94 tumor-NAT pairs, and RNA sequencing in 83 tumor-NAT pairs. Our analysis reveals an extensively altered proteome and 252 potential druggable proteins in AEG tumors. We identify three proteomic subtypes with significant clinical and molecular differences. The S-II subtype signature protein, FBXO44, is demonstrated to promote tumor progression and metastasis in vitro and in vivo. Our comparative analyses reveal distinct genomic features in AEG subtypes. We find a specific decrease of fibroblasts in the S-III subtype. Further phosphoproteomic comparisons reveal different kinase-phosphosubstrate regulatory networks among AEG subtypes. Our proteogenomics dataset provides valuable resources for understanding molecular mechanisms and developing precision treatment strategies of AEG.
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Kuo CJ, Ke JN, Kuo T, Lin CY, Hsieh SY, Chiu YF, Wu HY, Huang MZ, Bui NN, Chiu CH, Chiu CT, Lai CH. Multiple amino acid substitutions in penicillin-binding protein-1A confer amoxicillin resistance in refractory Helicobacter pylori infection. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2023; 56:40-47. [PMID: 35995672 DOI: 10.1016/j.jmii.2022.07.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Revised: 06/06/2022] [Accepted: 07/21/2022] [Indexed: 02/07/2023]
Abstract
BACKGROUND Amoxicillin resistance in Helicobacter pylori is mainly associated with mutations in penicillin-binding protein-1A (PBP-1A). However, the specific amino acid substitutions in PBP-1A that confer amoxicillin resistance in H. pylori remain to be investigated. OBJECTIVE This study aimed to investigate the molecular mechanism underlying amoxicillin resistance in patients with refractory H. pylori infection. METHODS Esophagogastroduodenoscopy (EGD) was performed in patients with persistent H. pylori infection after at least two courses of H. pylori eradication therapy between January-2018 to March-2021. Refractory H. pylori was cultured from the gastric biopsy specimens. Antibiotic susceptibility testing was conducted to determine the minimum inhibitory concentrations (MICs). Sequence analysis of pbp-1A was performed for amoxicillin-resistant strains. RESULTS Thirty-nine successfully cultured isolates were classified as refractory H. pylori isolates, and seventeen isolates were resistant to amoxicillin (MIC > 0.125 mg/L). Sequence analysis of resistant strains showed multiple mutations in the C-terminal region of PBP-1A that conferred amoxicillin resistance in H. pylori. However, the number of PBP-1A mutations did not correlate with the high MICs of amoxicillin-resistant isolates. Notably, some amino acid substitutions were identified in all Taiwanese isolates with history of eradication failure but not in published amoxicillin-susceptible strains, suggesting that the mutations may play a role in conferring antibiotic resistance to these strains. CONCLUSIONS Our results show that amoxicillin resistance in refractory H. pylori is highly correlated with numerous PBP-1A mutations that are strain specific. Continuous improvements in diagnostic tools, particularly molecular analysis approaches, can help to optimize current antimicrobial regimens.
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Affiliation(s)
- Chia-Jung Kuo
- Department of Gastroenterology and Hepatology, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan; School of Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Jun-Nong Ke
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Tony Kuo
- Department of Gastroenterology and Hepatology, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan; School of Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Cheng-Yu Lin
- Department of Gastroenterology and Hepatology, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan; School of Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Sen-Yung Hsieh
- Department of Gastroenterology and Hepatology, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan; School of Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan; Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Ya-Fang Chiu
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan; Molecular Infectious Disease Research Center, Department of Laboratory Medicine, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan; Department of Microbiology and Immunology, Research Center for Emerging Viral Infections, Chang Gung University, Taoyuan, Taiwan
| | - Hui-Yu Wu
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Mei-Zi Huang
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Ngoc-Niem Bui
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan; Faculty of Medicine, Can Tho University of Medicine and Pharmacy, Can Tho, Viet Nam
| | - Cheng-Hsun Chiu
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan; Department of Pediatrics, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan; Molecular Infectious Disease Research Center, Department of Laboratory Medicine, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan
| | - Cheng-Tang Chiu
- Department of Gastroenterology and Hepatology, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan; School of Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Chih-Ho Lai
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan; Molecular Infectious Disease Research Center, Department of Laboratory Medicine, Chang Gung Memorial Hospital at Linkou, Taoyuan, Taiwan; Department of Microbiology and Immunology, Research Center for Emerging Viral Infections, Chang Gung University, Taoyuan, Taiwan; Department of Medical Research, School of Medicine, China Medical University and Hospital, Taichung, Taiwan; Department of Nursing, Asia University, Taichung, Taiwan.
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Mechanism of regulation of the Helicobacter pylori Cagβ ATPase by CagZ. Nat Commun 2023; 14:479. [PMID: 36717564 PMCID: PMC9886983 DOI: 10.1038/s41467-023-36218-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 01/20/2023] [Indexed: 02/01/2023] Open
Abstract
The transport of the CagA effector into gastric epithelial cells by the Cag Type IV secretion system (Cag T4SS) of Helicobacter pylori (H. pylori) is critical for pathogenesis. CagA is recruited to Cag T4SS by the Cagβ ATPase. CagZ, a unique protein in H. pylori, regulates Cagβ-mediated CagA transport, but the underlying mechanisms remain unclear. Here we report the crystal structure of the cytosolic region of Cagβ, showing a typical ring-like hexameric assembly. The central channel of the ring is narrow, suggesting that CagA must unfold for transport through the channel. Our structure of CagZ in complex with the all-alpha domain (AAD) of Cagβ shows that CagZ adopts an overall U-shape and tightly embraces Cagβ. This binding mode of CagZ is incompatible with the formation of the Cagβ hexamer essential for the ATPase activity. CagZ therefore inhibits Cagβ by trapping it in the monomeric state. Based on these findings, we propose a refined model for the transport of CagA by Cagβ.
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Zhang J, Hai X, Wang S, Zhu F, Gu Y, Meng G, Zhang Q, Liu L, Wu H, Zhang S, Zhang T, Wang X, Sun S, Zhou M, Jia Q, Song K, Niu K. Helicobacter pylori infection increase the risk of subclinical hyperthyroidism in middle-aged and elderly women independent of dietary factors: Results from the Tianjin chronic low-grade systemic inflammation and health cohort study in China. Front Nutr 2023; 10:1002359. [PMID: 36950328 PMCID: PMC10025335 DOI: 10.3389/fnut.2023.1002359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Accepted: 02/06/2023] [Indexed: 03/08/2023] Open
Abstract
Background Prospective studies on the association between Helicobacter pylori (H. pylori) infection and subclinical hyperthyroidism are limited. We, therefore, designed a large-scale cohort study to explore the association between H. pylori infection and the risk of subclinical hyperthyroidism in women. Methods This prospective cohort study investigated 2,713 participants. H. pylori infection was diagnosed with the carbon 13 breath test. Subclinical hyperthyroidism was defined as serum thyroid-stimulating hormone levels are low or undetectable but free thyroxine and tri-iodothyronine concentrations are normal. Propensity score matching (PSM) analyses and Cox proportional hazards regression models were used to estimate the association between H. pylori infection and subclinical hyperthyroidism. Results A total of 1,025 PS-matched pairs of H. pylori infection women were generated after PSM. During 6 years of follow-up, the incidence rate of subclinical hyperthyroidism was 7.35/1,000 person-years. After adjusting potential confounding factors (including iodine intake in food and three main dietary patterns score), the multivariable hazard ratio (HR; 95% confidence intervals) of subclinical hyperthyroidism by H. pylori infection was 2.49 (1.36, 4.56). Stratified analyses suggested a potential effect modification by age, the multivariable HR (95% confidence intervals) was 2.85 (1.45, 5.61) in participants aged ≥ 40 years and 0.70 (0.08, 6.00) in participants aged < 40 years (P for interaction = 0.048). Conclusion Our prospective study first indicates that H. pylori infection is significantly associated with the risk of subclinical hyperthyroidism independent of dietary factors among Chinese women, especially in middle-aged and older individuals.Clinical Trial Registration:https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000031137, identifier UMIN000027174.
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Affiliation(s)
- Juanjuan Zhang
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
| | - Xinghua Hai
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
- School of Public Health of Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Siyu Wang
- School of Public Health of Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Fan Zhu
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
| | - Yeqing Gu
- Institute of Radiation Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China
- *Correspondence: Yeqing Gu,
| | - Ge Meng
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
| | - Qing Zhang
- Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China
| | - Li Liu
- Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China
| | - Hongmei Wu
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
| | - Shunming Zhang
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
| | - Tingjing Zhang
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
| | - Xing Wang
- Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China
| | - Shaomei Sun
- Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China
| | - Ming Zhou
- Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China
| | - Qiyu Jia
- Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China
| | - Kun Song
- Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China
| | - Kaijun Niu
- Nutritional Epidemiology Institute and School of Public Health, Tianjin Medical University, Tianjin, China
- School of Public Health of Tianjin University of Traditional Chinese Medicine, Tianjin, China
- Institute of Radiation Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, China
- Health Management Centre, Tianjin Medical University General Hospital, Tianjin, China
- Tianjin Key Laboratory of Environment, Nutrition and Public Health, Tianjin, China
- Center for International Collaborative Research on Environment, Nutrition and Public Health, Tianjin, China
- Kaijun Niu,
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39
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Yamaoka Y, Saruuljavkhlan B, Alfaray RI, Linz B. Pathogenomics of Helicobacter pylori. Curr Top Microbiol Immunol 2023; 444:117-155. [PMID: 38231217 DOI: 10.1007/978-3-031-47331-9_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
The human stomach bacterium Helicobacter pylori, the causative agent of gastritis, ulcers and adenocarcinoma, possesses very high genetic diversity. H. pylori has been associated with anatomically modern humans since their origins over 100,000 years ago and has co-evolved with its human host ever since. Predominantly intrafamilial and local transmission, along with genetic isolation, genetic drift, and selection have facilitated the development of distinct bacterial populations that are characteristic for large geographical areas. H. pylori utilizes a large arsenal of virulence and colonization factors to mediate the interaction with its host. Those include various adhesins, the vacuolating cytotoxin VacA, urease, serine protease HtrA, the cytotoxin-associated genes pathogenicity island (cagPAI)-encoded type-IV secretion system and its effector protein CagA, all of which contribute to disease development. While many pathogenicity-related factors are present in all strains, some belong to the auxiliary genome and are associated with specific phylogeographic populations. H. pylori is naturally competent for DNA uptake and recombination, and its genome evolution is driven by extraordinarily high recombination and mutation rates that are by far exceeding those in other bacteria. Comparative genome analyses revealed that adaptation of H. pylori to individual hosts is associated with strong selection for particular protein variants that facilitate immune evasion, especially in surface-exposed and in secreted virulence factors. Recent studies identified single-nucleotide polymorphisms (SNPs) in H. pylori that are associated with the development of severe gastric disease, including gastric cancer. Here, we review the current knowledge about the pathogenomics of H. pylori.
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Affiliation(s)
- Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, 1-1, Idaigaoka, Hasama-machi, Yufu Oita, 879-5593, Japan
- Department of Medicine, Gastroenterology and Hepatology Section, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Batsaikhan Saruuljavkhlan
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, 1-1, Idaigaoka, Hasama-machi, Yufu Oita, 879-5593, Japan
| | - Ricky Indra Alfaray
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, 1-1, Idaigaoka, Hasama-machi, Yufu Oita, 879-5593, Japan
- Helicobacter pylori and Microbiota Study Group, Universitas Airlangga, Surabaya, 60286, East Java, Indonesia
| | - Bodo Linz
- Division of Microbiology, Department Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, 91058, Erlangen, Germany.
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40
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Kumar S, Mehrotra T, Talukdar D, Verma J, Chandra Karmakar B, Paul S, Chaudhuri S, Kumari Pragasam A, Bakshi S, Kumari S, Chawla M, Purohit A, Porey Karmakar S, Mutreja A, Banerjee S, Ray A, Ramamurthy T, Mukhopadyay AK, Das B. Region-specific genomic signatures of multidrug-resistant Helicobacter pylori isolated from East and South India. Gene 2022; 847:146857. [PMID: 36100116 DOI: 10.1016/j.gene.2022.146857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 08/08/2022] [Accepted: 08/29/2022] [Indexed: 11/19/2022]
Abstract
Helicobacter pylori is a ubiquitous bacterium and contributes significantly to the burden of chronic gastritis, peptic ulcers, and gastric cancer across the world. Adaptive phenotypes and virulence factors in H. pylori are heterogeneous and dynamic. However, limited information is available about the molecular nature of antimicrobial resistance phenotypes and virulence factors of H. pylori strains circulating in India. In the present study, we analyzed the whole genome sequences of 143 H. pylori strains, of which 32 are isolated from two different regions (eastern and southern) of India. Genomic repertoires of individual strains show distinct region-specific signatures. We observed lower resistance phenotypes and genotypes in the East Indian (Kolkata) H. pylori isolates against amoxicillin and furazolidone antibiotics, whereas higher resistance phenotypes to metronidazole and clarithromycin. Also, at molecular level, a greater number of AMR genes were observed in the east Indian H. pylori isolates as compared to the southern Indian isolates. From our findings, we suggest that metronidazole and clarithromycin antibiotics should be used judicially in the eastern India. However, no horizontally acquired antimicrobial resistance gene was observed in the current H. pylori strains. The comparative genome analysis shows that the number of genes involved in virulence, disease and resistance of H. pylori isolated from two different regions of India is significantly different. Single-nucleotide polymorphisms (SNPs) based phylogenetic analysis distinguished H. pylori strains into different clades according to their geographical locations. Conditionally beneficial functions including antibiotic resistance phenotypes that are linked with faster evolution rates in the Indian isolates.
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Affiliation(s)
- Shakti Kumar
- Molecular Genetics Laboratory, Infection and Immunology Division, Translational Health Science and Technology Institute, Faridabad, India
| | - Tanshi Mehrotra
- Molecular Genetics Laboratory, Infection and Immunology Division, Translational Health Science and Technology Institute, Faridabad, India
| | - Daizee Talukdar
- Molecular Genetics Laboratory, Infection and Immunology Division, Translational Health Science and Technology Institute, Faridabad, India
| | - Jyoti Verma
- Molecular Genetics Laboratory, Infection and Immunology Division, Translational Health Science and Technology Institute, Faridabad, India
| | - Bipul Chandra Karmakar
- Division of Bacteriology, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Sangita Paul
- Division of Bacteriology, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Sujit Chaudhuri
- Department of Gastroenterology, AMRI Hospital, Salt Lake, Kolkata, India
| | - Agila Kumari Pragasam
- Molecular Genetics Laboratory, Infection and Immunology Division, Translational Health Science and Technology Institute, Faridabad, India
| | - Susmita Bakshi
- Molecular Genetics Laboratory, Infection and Immunology Division, Translational Health Science and Technology Institute, Faridabad, India
| | - Shashi Kumari
- Molecular Genetics Laboratory, Infection and Immunology Division, Translational Health Science and Technology Institute, Faridabad, India
| | - Meenal Chawla
- Molecular Genetics Laboratory, Infection and Immunology Division, Translational Health Science and Technology Institute, Faridabad, India
| | - Ayushi Purohit
- Molecular Genetics Laboratory, Infection and Immunology Division, Translational Health Science and Technology Institute, Faridabad, India
| | - Sonali Porey Karmakar
- Molecular Genetics Laboratory, Infection and Immunology Division, Translational Health Science and Technology Institute, Faridabad, India
| | - Ankur Mutreja
- Department of Medicine, Addenbrookes Hospital, University of Cambridge, Cambridge CB20QQ, United Kingdom
| | - Sayantan Banerjee
- Department of Microbiology, All India Institute of Medical Sciences, Kalyani, India
| | - Animesh Ray
- Department of Medicine, All India Institute of Medical Science, New Delhi, India
| | - Thandavarayan Ramamurthy
- Division of Bacteriology, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Asish K Mukhopadyay
- Division of Bacteriology, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Bhabatosh Das
- Molecular Genetics Laboratory, Infection and Immunology Division, Translational Health Science and Technology Institute, Faridabad, India.
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Baksh KA, Augustine J, Sljoka A, Prosser RS, Zamble DB. Mechanistic insights into the nickel-dependent allosteric response of the Helicobacter pylori NikR transcription factor. J Biol Chem 2022; 299:102785. [PMID: 36502919 PMCID: PMC9860126 DOI: 10.1016/j.jbc.2022.102785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 11/30/2022] [Accepted: 12/03/2022] [Indexed: 12/13/2022] Open
Abstract
In Helicobacter pylori, the nickel-responsive NikR transcription factor plays a key role in regulating intracellular nickel concentrations, which is an essential process for survival of this pathogen in the acidic human stomach. Nickel binding to H. pylori NikR (HpNikR) allosterically activates DNA binding to target promoters encoding genes involved in nickel homeostasis and acid adaptation, to either activate or repress their transcription. We previously showed that HpNikR adopts an equilibrium between an open conformation and DNA-binding competent cis and trans states. Nickel binding slows down conformational exchange between these states and shifts the equilibrium toward the binding-competent states. The protein then becomes stabilized in a cis conformation upon binding the ureA promoter. Here, we investigate how nickel binding creates this response and how it is transmitted to the DNA-binding domains. Through mutagenesis, DNA-binding studies, and computational methods, the allosteric response to nickel was found to be propagated from the nickel-binding sites to the DNA-binding domains via the β-sheets of the metal-binding domain and a network of residues at the inter-domain interface. Our computational results suggest that nickel binding increases protein rigidity to slow down the conformational exchange. A thymine base in the ureA promoter sequence, known to be critical for high affinity DNA binding by HpNikR, was also found to be important for the allosteric response, while a modified version of this promoter further highlighted the importance of the DNA sequence in modulating the response. Collectively, our results provide insights into regulation of a key protein for H. pylori survival.
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Affiliation(s)
- Karina A. Baksh
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Jerry Augustine
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - Adnan Sljoka
- RIKEN Center for Advanced Intelligence Project, RIKEN, Chuo-ku, Tokyo, Japan,For correspondence: R. Scott Prosser; Adnan Sljoka
| | - R. Scott Prosser
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada,Department of Chemistry, University of Toronto, Toronto, Ontario, Canada,For correspondence: R. Scott Prosser; Adnan Sljoka
| | - Deborah B. Zamble
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada,Department of Chemistry, University of Toronto, Toronto, Ontario, Canada
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Guevara-Tique AA, Torres RC, Bravo MM, Carvajal Carmona LG, Echeverry de Polanco MM, Bohórquez ME, Torres J. Recombination events drives the emergence of Colombian Helicobacter pylori subpopulations with self-identity ancestry. Virulence 2022; 13:1146-1160. [PMID: 35838227 PMCID: PMC9291697 DOI: 10.1080/21505594.2022.2095737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Helicobacter pylori have coevolved with mankind since its origins, adapting to different human groups. In America, H. pylori has evolved into several subpopulations. We analysed the genome of 154 Colombian strains along with 1,091 strains from worldwide populations to discern the ancestry and adaption to Colombian people. Population structure and ancestry was inferred with FineStructure and ChromoPainter. Phylogenetic relationship and the relative effect of recombination were analysing the core SNPs. Also, a Fst index was calculated to identify the gene variants with the strongest fixation in the Colombian subpopulations compared to their parent population hspSWEurope. FineStructure allowed the identification of two Colombian subpopulations, the previously described hspSWEuropeColombia and a novel subpopulation named hspColombia, that included three subgroups following their geographic origin. Colombian subpopulations represent an admixture of European, African and Indigenous ancestry; although some genomes showed a high proportion of self identity, suggesting an advanced adaption to these mestizo Colombian groups. We found that recombination is more important that punctual mutations in H. pylori genome diversity, 13.9 more important in hspSWEurope, 12.5 in hspSWEColombia and 10.5 in hspColombia, reflecting the divergence of these subpopulations. Fst analysis identified 82 SNPs fixed in 26 genes of the hspColombia subpopulation that encode for outer membrane and central metabolism proteins. Strongest fixation indexes were identified in genes encoding HofC, HopE, FrpB-4 and Sialidase A. These findings demonstrate that H. pylori has evolved in Colombia to give rise to subpopulations with a self identity ancestry, reflected in allele changes on genes encoding for outer membrane proteins.
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Affiliation(s)
- Alix A Guevara-Tique
- Grupo de Investigación en Citogenética, Filogenia y Evolución de Poblaciones, Departamento de Ciencias y Ciencias de la Salud, Universidad del Tolima, Tolima, Colombia
| | - Roberto C Torres
- The Center for Microbes, Development and Health, CAS Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China
| | - Maria M Bravo
- Laboratorio de Inmunología, Instituto Nacional de Cancerología, Bogotá, D. C., Colombia
| | - Luis G Carvajal Carmona
- Genome Center, Department of Biochemistry and Molecular Medicine, School of Medicine-University of California, Davis, California, USA
| | - María M Echeverry de Polanco
- Grupo de Investigación en Citogenética, Filogenia y Evolución de Poblaciones, Departamento de Ciencias y Ciencias de la Salud, Universidad del Tolima, Tolima, Colombia
| | - Mabel E Bohórquez
- Grupo de Investigación en Citogenética, Filogenia y Evolución de Poblaciones, Departamento de Ciencias y Ciencias de la Salud, Universidad del Tolima, Tolima, Colombia.,Medicine Program, Department of Health Sciences, Tolima University, Tolima, Colombia
| | - Javier Torres
- c Unidad de Investigación en Enfermedades Infecciosas, UMAE Pediatria, Instituto Mexicano del Seguro Social, México
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Somiah T, Gebremariam HG, Zuo F, Smirnova K, Jonsson AB. Lactate causes downregulation of Helicobacter pylori adhesin genes sabA and labA while dampening the production of proinflammatory cytokines. Sci Rep 2022; 12:20064. [PMID: 36414643 PMCID: PMC9681763 DOI: 10.1038/s41598-022-24311-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 11/14/2022] [Indexed: 11/24/2022] Open
Abstract
Chronic inflammation induced by Helicobacter pylori is strongly associated with gastric cancer development, which is influenced by both bacterial virulence and host genetics. The sialic acid-binding adhesin SabA and the MUC5AC-binding adhesin LabA are important H. pylori virulence factors that facilitate adhesion of the bacterium, which is a crucial step in colonization. Lactate utilization has been reported to play a key role in the pathogenicity of different bacterial species. However, this is poorly understood in H. pylori. In this study, we investigated the effect of lactate on H. pylori adhesin gene expression and the regulation of host inflammatory cytokines. We show that the bacterial adhesins SabA and LabA were downregulated at the transcriptional level during incubation of H. pylori with lactate. Downregulation of sabA required the involvement of the two-component system ArsRS, while labA was regulated via the CheA/CheY system, indicating differences in the regulation of these genes in response to lactate. The levels of the proinflammatory cytokines TNF and IL-6 in H. pylori-stimulated macrophages were reduced when lactate was present. Interestingly, glucose did not prevent the secretion of these cytokines. Taken together, our data suggest that lactate affects H. pylori adhesin gene expression and the host response upon infection.
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Affiliation(s)
- Tanvi Somiah
- grid.10548.380000 0004 1936 9377Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrheniusväg 20C, 10691 Stockholm, Sweden
| | - Hanna G. Gebremariam
- grid.10548.380000 0004 1936 9377Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrheniusväg 20C, 10691 Stockholm, Sweden
| | - Fanglei Zuo
- grid.10548.380000 0004 1936 9377Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrheniusväg 20C, 10691 Stockholm, Sweden
| | - Ksenija Smirnova
- grid.10548.380000 0004 1936 9377Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrheniusväg 20C, 10691 Stockholm, Sweden
| | - Ann-Beth Jonsson
- grid.10548.380000 0004 1936 9377Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Svante Arrheniusväg 20C, 10691 Stockholm, Sweden
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44
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Insights into the Orchestration of Gene Transcription Regulators in Helicobacter pylori. Int J Mol Sci 2022; 23:ijms232213688. [PMID: 36430169 PMCID: PMC9696931 DOI: 10.3390/ijms232213688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 10/31/2022] [Accepted: 11/04/2022] [Indexed: 11/09/2022] Open
Abstract
Bacterial pathogens employ a general strategy to overcome host defenses by coordinating the virulence gene expression using dedicated regulatory systems that could raise intricate networks. During the last twenty years, many studies of Helicobacter pylori, a human pathogen responsible for various stomach diseases, have mainly focused on elucidating the mechanisms and functions of virulence factors. In parallel, numerous studies have focused on the molecular mechanisms that regulate gene transcription to attempt to understand the physiological changes of the bacterium during infection and adaptation to the environmental conditions it encounters. The number of regulatory proteins deduced from the genome sequence analyses responsible for the correct orchestration of gene transcription appears limited to 14 regulators and three sigma factors. Furthermore, evidence is accumulating for new and complex circuits regulating gene transcription and H. pylori virulence. Here, we focus on the molecular mechanisms used by H. pylori to control gene transcription as a function of the principal environmental changes.
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45
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Dobaño C, Ramírez-Morros A, Alonso S, Rubio R, Ruiz-Olalla G, Vidal-Alaball J, Macià D, Catalina QM, Vidal M, Casanovas AF, Prados de la Torre E, Barrios D, Jiménez A, Zanoncello J, Melero NR, Carolis C, Izquierdo L, Aguilar R, Moncunill G, Ruiz-Comellas A. Sustained seropositivity up to 20.5 months after COVID-19. BMC Med 2022; 20:379. [PMID: 36224590 PMCID: PMC9556137 DOI: 10.1186/s12916-022-02570-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 09/15/2022] [Indexed: 01/09/2023] Open
Abstract
This study evaluated the persistence of IgM, IgA, and IgG to SARS-CoV-2 spike and nucleocapsid antigens up to 616 days since the onset of symptoms in a longitudinal cohort of 247 primary health care workers from Barcelona, Spain, followed up since the start of the pandemic. The study also assesses factors affecting antibody levels, including comorbidities and the responses to variants of concern as well as the frequency of reinfections. Despite a gradual and significant decline in antibody levels with time, seropositivity to five SARS-CoV-2 antigens combined was always higher than 90% over the whole study period. In a subset of 23 participants who had not yet been vaccinated by November 2021, seropositivity remained at 95.65% (47.83% IgM, 95.65% IgA, 95.65% IgG). IgG seropositivity against Alpha and Delta predominant variants was comparable to that against the Wuhan variant, while it was lower for Gamma and Beta (minority) variants and for IgA and IgM. Antibody levels at the time point closest to infection were associated with age, smoking, obesity, hospitalization, fever, anosmia/hypogeusia, chest pain, and hypertension in multivariable regression models. Up to 1 year later, just before the massive roll out of vaccination, antibody levels were associated with age, occupation, hospitalization, duration of symptoms, anosmia/hypogeusia, fever, and headache. In addition, tachycardia and cutaneous symptoms associated with slower antibody decay, and oxygen supply with faster antibody decay. Eight reinfections (3.23%) were detected in low responders, which is consistent with a sustained protective role for anti-spike naturally acquired antibodies. Stable persistence of IgG and IgA responses and cross-recognition of the predominant variants circulating in the 2020-2021 period indicate long-lasting and largely variant-transcending humoral immunity in the initial 20.5 months of the pandemic, in the absence of vaccination.
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Affiliation(s)
- Carlota Dobaño
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Carrer Roselló 153 (CEK building), E-08036, Barcelona, Spain. .,CIBER de Enfermedades Infecciosas, Barcelona, Spain.
| | - Anna Ramírez-Morros
- Unitat de Suport a la Recerca de la Catalunya Central, Fundació Institut Universitari per a la recerca a l'Atenció Primària de Salut Jordi Gol i Gurina, Sant Fruitós de Bages, Spain
| | - Selena Alonso
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Carrer Roselló 153 (CEK building), E-08036, Barcelona, Spain
| | - Rocío Rubio
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Carrer Roselló 153 (CEK building), E-08036, Barcelona, Spain
| | - Gemma Ruiz-Olalla
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Carrer Roselló 153 (CEK building), E-08036, Barcelona, Spain
| | - Josep Vidal-Alaball
- Unitat de Suport a la Recerca de la Catalunya Central, Fundació Institut Universitari per a la recerca a l'Atenció Primària de Salut Jordi Gol i Gurina, Sant Fruitós de Bages, Spain.,Grup de Promoció de la Salut en l'Àmbit Rural (ProSaARu), Institut Català de la Salut, Sant Fruitós de Bages, Spain.,Facultat de Medicina, Universitat de Vic-Universitat Central de Catalunya (UVIC-UCC), Vic, Spain
| | - Dídac Macià
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Carrer Roselló 153 (CEK building), E-08036, Barcelona, Spain.,CIBER de Enfermedades Infecciosas, Barcelona, Spain
| | - Queralt Miró Catalina
- Unitat de Suport a la Recerca de la Catalunya Central, Fundació Institut Universitari per a la recerca a l'Atenció Primària de Salut Jordi Gol i Gurina, Sant Fruitós de Bages, Spain
| | - Marta Vidal
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Carrer Roselló 153 (CEK building), E-08036, Barcelona, Spain
| | - Aina Fuster Casanovas
- Unitat de Suport a la Recerca de la Catalunya Central, Fundació Institut Universitari per a la recerca a l'Atenció Primària de Salut Jordi Gol i Gurina, Sant Fruitós de Bages, Spain
| | - Esther Prados de la Torre
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Carrer Roselló 153 (CEK building), E-08036, Barcelona, Spain
| | - Diana Barrios
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Carrer Roselló 153 (CEK building), E-08036, Barcelona, Spain
| | - Alfons Jiménez
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Carrer Roselló 153 (CEK building), E-08036, Barcelona, Spain
| | - Jasmina Zanoncello
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Carrer Roselló 153 (CEK building), E-08036, Barcelona, Spain
| | - Natalia Rodrigo Melero
- Biomolecular Screening and Protein Technologies Unit, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Carlo Carolis
- Biomolecular Screening and Protein Technologies Unit, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Luis Izquierdo
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Carrer Roselló 153 (CEK building), E-08036, Barcelona, Spain.,CIBER de Enfermedades Infecciosas, Barcelona, Spain
| | - Ruth Aguilar
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Carrer Roselló 153 (CEK building), E-08036, Barcelona, Spain
| | - Gemma Moncunill
- ISGlobal, Hospital Clínic - Universitat de Barcelona, Barcelona, Carrer Roselló 153 (CEK building), E-08036, Barcelona, Spain.,CIBER de Enfermedades Infecciosas, Barcelona, Spain
| | - Anna Ruiz-Comellas
- Unitat de Suport a la Recerca de la Catalunya Central, Fundació Institut Universitari per a la recerca a l'Atenció Primària de Salut Jordi Gol i Gurina, Sant Fruitós de Bages, Spain.,Grup de Promoció de la Salut en l'Àmbit Rural (ProSaARu), Institut Català de la Salut, Sant Fruitós de Bages, Spain.,Facultat de Medicina, Universitat de Vic-Universitat Central de Catalunya (UVIC-UCC), Vic, Spain.,Centre d'Atenció Primària (CAP) Sant Joan de Vilatorrada. Gerència Territorial de la Catalunya Central, Institut Català de la Salut, Sant Fruitós de Bages, Spain
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Teng KW, Hsieh KS, Hung JS, Wang CJ, Liao EC, Chen PC, Lin YH, Wu DC, Lin CH, Wang WC, Chan HL, Huang SK, Kao MC. Helicobacter pylori employs a general protein glycosylation system for the modification of outer membrane adhesins. Gut Microbes 2022; 14:2130650. [PMID: 36206406 PMCID: PMC9553153 DOI: 10.1080/19490976.2022.2130650] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Helicobacter pylori infection is associated with the development of several gastric diseases including gastric cancer. To reach a long-term colonization in the host stomach, H. pylori employs multiple outer membrane adhesins for binding to the gastric mucosa. However, due to the redundancy of adhesins that complement the adhesive function of bacteria, targeting each individual adhesin alone usually achieves nonideal outcomes for preventing bacterial adhesion. Here, we report that key adhesins AlpA/B and BabA/B in H. pylori are modified by glycans and display a two-step molecular weight upshift pattern from the cytoplasm to the inner membrane and from the inner membrane to the outer membrane. Nevertheless, this upshift pattern is missing when the expression of some enzymes related to lipopolysaccharide (LPS) biosynthesis, including the LPS O-antigen assembly and ligation enzymes WecA, Wzk, and WaaL, is disrupted, indicating that the underlying mechanisms and the involved enzymes for the adhesin glycosylation are partially shared with the LPS biosynthesis. Loss of the adhesin glycosylation not only reduces the protease resistance and the stability of the tested adhesins but also changes the adhesin-binding ability. In addition, mutations in the LPS biosynthesis cause a significant reduction in bacterial adhesion in the in vitro cell-line model. The current findings reveal that H. pylori employs a general protein glycosylation system related to LPS biosynthesis for adhesin modification and its biological significance. The enzymes required for adhesin glycosylation rather than the adhesins themselves are potentially better drug targets for preventing or treating H. pylori infection.
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Affiliation(s)
- Kai-Wen Teng
- Institute of Molecular Medicine, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Kai-Siang Hsieh
- Institute of Molecular Medicine, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Ji-Shiuan Hung
- Institute of Molecular Medicine, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Chun-Jen Wang
- Institute of Molecular Medicine, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - En-Chi Liao
- Institute of Bioinformatics and Structural Biology, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan,Department of Medical Science, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Pei-Chun Chen
- Institute of Molecular Medicine, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Ying-Hsuan Lin
- Institute of Molecular Medicine, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Deng-Chyang Wu
- Division of Gastroenterology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chun-Hung Lin
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Wen-Ching Wang
- Institute of Molecular and Cellular Biology, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan,Department of Life Science, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Hong-Lin Chan
- Institute of Bioinformatics and Structural Biology, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan,Department of Medical Science, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Shau-Ku Huang
- National Institute of Environmental Health Sciences, National Health Research Institutes, Zhunan, Taiwan
| | - Mou-Chieh Kao
- Institute of Molecular Medicine, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan,Department of Life Science, College of Life Science, National Tsing Hua University, Hsinchu, Taiwan,CONTACT Mou-Chieh Kao Institute of Molecular Medicine, College of Life Science, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu 300044, Taiwan
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The Helicobacter pylori UvrC Nuclease Is Essential for Chromosomal Microimports after Natural Transformation. mBio 2022; 13:e0181122. [PMID: 35876509 PMCID: PMC9426483 DOI: 10.1128/mbio.01811-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Helicobacter pylori is a Gram-negative bacterial carcinogenic pathogen that infects the stomachs of half of the human population. It is a natural mutator due to a deficient DNA mismatch repair pathway and is naturally competent for transformation. As a result, it is one of the most genetically diverse human bacterial pathogens. The length of chromosomal imports in H. pylori follows an unusual bimodal distribution consisting of macroimports with a mean length of 1,645 bp and microimports with a mean length of 28 bp. The mechanisms responsible for this import pattern were unknown. Here, we used a high-throughput whole-genome transformation assay to elucidate the role of nucleotide excision repair pathway (NER) components on import length distribution. The data show that the integration of microimports depended on the activity of the UvrC endonuclease, while none of the other components of the NER pathway was required. Using H. pylori site-directed mutants, we showed that the widely conserved UvrC nuclease active sites, while essential for protection from UV light, one of the canonical NER functions, are not required for generation of microimports. A quantitative analysis of recombination patterns based on over 1,000 imports from over 200 sequenced recombinant genomes showed that microimports occur frequently within clusters of multiple imports, strongly suggesting they derive from a single strand invasion event. We propose a hypothetical model of homologous recombination in H. pylori, involving a novel function of UvrC, that reconciles the available experimental data about recombination patterns in H. pylori. IMPORTANCE Helicobacter pylori is one of the most common and genetically diverse human bacterial pathogens. It is responsible for chronic gastritis and represents the main risk factor for gastric cancer. In H. pylori, DNA fragments can be imported by recombination during natural transformation. The length of those fragments determines how many potentially beneficial or deleterious alleles are acquired and thus influences adaptation to the gastric niche. Here, we used a transformation assay to examine imported fragments across the chromosome. We show that UvrC, an endonuclease involved in DNA repair, is responsible for the specific integration of short DNA fragments. This suggests that short and long fragments are imported through distinct recombination pathways. We also show that short fragments are frequently clustered with longer fragments, suggesting that both pathways may be mechanistically linked. These findings provide a novel basis to explain how H. pylori can fine-tune the genetic diversity acquired by transformation.
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Exploiting Violet-Blue Light to Kill Campylobacter jejuni: Analysis of Global Responses, Modeling of Transcription Factor Activities, and Identification of Protein Targets. mSystems 2022; 7:e0045422. [PMID: 35924857 PMCID: PMC9426514 DOI: 10.1128/msystems.00454-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Campylobacter jejuni is a microaerophilic foodborne zoonotic pathogen of worldwide concern as the leading cause of bacterial gastroenteritis. Many strains are increasingly antibiotic resistant and new methods of control are required to reduce food-chain contamination. One possibility is photodynamic inactivation (PDI) using violet-blue (VB) light, to which C. jejuni is highly susceptible. Here, we show that flavin and protoporphyrin IX are major endogenous photosensitizers and that exposure of cells to VB light increases intracellular reactive oxygen species (ROS) to high levels, as indicated by a dichlorodihydrofluorescein reporter. Unusually for an oxygen-respiring bacterium, C. jejuni employs several ROS-sensitive iron-sulfur cluster enzymes in central metabolic pathways; we show that VB light causes rapid inactivation of both pyruvate and 2-oxoglutarate oxidoreductases, thus interrupting the citric acid cycle. Cells exposed to VB light also lose heme from c-type cytochromes, restricting electron transport, likely due to irreversible oxidation of heme-ligating cysteine residues. Evaluation of global gene expression changes by RNAseq and probabilistic modeling showed a two-stage protein damage/oxidative stress response to VB light, driven by specific regulators, including HspR, PerR, Fur, and RacR. Deletion mutant analysis showed that superoxide dismutase and the cytochrome CccA were particularly important for VB light survival and that abolishing repression of chaperones and oxidative stress resistance genes by HcrA, HspR, or PerR increased tolerance to VB light. Our results explain the high innate sensitivity of C. jejuni to VB light and provide new insights that may be helpful in exploiting PDI for novel food-chain interventions to control this pathogen. IMPORTANCE Campylobacteriosis caused by C. jejuni is one of the most widespread zoonotic enteric diseases worldwide and represents an enormous human health and economic burden, compounded by the emergence of antibiotic-resistant strains. New interventions are urgently needed to reduce food-chain contamination. Although UV light is well known to be bactericidal, it is highly mutagenic and problematic for continuous exposure in food production facilities; in contrast, narrow spectrum violet-blue (VB) light is much safer. We confirmed that C. jejuni is highly susceptible to VB light and then identified some of the global regulatory networks involved in responding to photo-oxidative damage. The identification of damaged cellular components underpins efforts to develop commercial applications of VB light-based technologies.
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Holtrup S, Greger M, Mayer B, Specht M, Waidner B. Insights Into the Helical Shape Complex of Helicobacter pylori. Front Microbiol 2022; 13:929194. [PMID: 36090072 PMCID: PMC9448923 DOI: 10.3389/fmicb.2022.929194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 06/13/2022] [Indexed: 11/13/2022] Open
Abstract
One important factor that promotes the colonization of the upper digestive system of the human pathogen Helicobacter pylori is its helical cell shape. The bacteria cell shape is predominantly defined by its peptidoglycan cell wall. In rod-shaped species, PG synthesis is mediated by two dynamic molecular machines that facilitate growth along the perpendicular axis and the septum, called the elongasome and the divisome, respectively. Furthermore, many bacteria evolved additional mechanisms to locally change PG synthesis patterns to generate diverse cell shapes. Recent work characterizing cell shape mutants of Helicobacter pylori revealed a novel mechanism for the generation of a twisted helix from a rod, including PG-modifying enzymes as well as additional proteins such as the bactofilin homolog CcmA or the membrane proteins Csd5 and Csd7. In this study, we investigate the localization and dynamics of CcmA and Csd7 using live-cell imaging. We also address the question of how these change in the presence or absence of the putative interaction partners.
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Affiliation(s)
- Sven Holtrup
- LOEWE Center for Synthetic Microbiology, Marburg, Germany
- Department of Biochemistry and Chemistry, Philipps University of Marburg, Marburg, Germany
| | - Maximilian Greger
- LOEWE Center for Synthetic Microbiology, Marburg, Germany
- Department of Biochemistry and Chemistry, Philipps University of Marburg, Marburg, Germany
| | - Benjamin Mayer
- LOEWE Center for Synthetic Microbiology, Marburg, Germany
- Department of Biochemistry and Chemistry, Philipps University of Marburg, Marburg, Germany
| | - Mara Specht
- LOEWE Center for Synthetic Microbiology, Marburg, Germany
| | - Barbara Waidner
- LOEWE Center for Synthetic Microbiology, Marburg, Germany
- Department of Biochemistry and Chemistry, Philipps University of Marburg, Marburg, Germany
- *Correspondence: Barbara Waidner,
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50
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Xia X. Multiple regulatory mechanisms for pH homeostasis in the gastric pathogen, Helicobacter pylori. ADVANCES IN GENETICS 2022; 109:39-69. [PMID: 36334916 DOI: 10.1016/bs.adgen.2022.07.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Acid-resistance in gastric pathogen Helicobacter pylori requires the coordination of four essential processes to regulate urease activity. Firstly, urease expression above a base level needs to be finely tuned at different ambient pH. Secondly, as nickel is needed to activate urease, nickel homeostasis needs to be maintained by proteins that import and export nickel ions, and sequester, store and release nickel when needed. Thirdly, urease accessary proteins that activate urease activity by nickel insertion need to be expressed. Finally, a reliable source of urea needs to be maintained by both intrinsic and extrinsic sources of urea. Two-component systems (arsRS and flgRS), as well as a nickel response regulator (NikR), sense the change in pH and act on a variety of genes to accomplish the function of acid resistance without causing cellular overalkalization and nickel toxicity. Nickel storage proteins also feature built-in switches to store nickel at neutral pH and release nickel at low pH. This review summarizes the current status of H. pylori research and highlights a number of hypotheses that need to be tested.
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Affiliation(s)
- Xuhua Xia
- Department of Biology, University of Ottawa, Ottawa, Canada; Ottawa Institute of Systems Biology, Ottawa, Canada.
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