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Linz B, Sticht H, Tegtmeyer N, Backert S. Cancer-associated SNPs in bacteria: lessons from Helicobacter pylori. Trends Microbiol 2024; 32:847-857. [PMID: 38485609 DOI: 10.1016/j.tim.2024.02.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 02/01/2024] [Accepted: 02/02/2024] [Indexed: 09/06/2024]
Abstract
Several single-nucleotide polymorphisms (SNPs) in human chromosomes are known to predispose to cancer. However, cancer-associated SNPs in bacterial pathogens were unknown until discovered in the stomach pathogen Helicobacter pylori. Those include an alanine-threonine polymorphism in the EPIYA-B phosphorylation motif of the injected effector protein CagA that affects cancer risk by modifying inflammatory responses and loss of host cell polarity. A serine-to-leucine change in serine protease HtrA is associated with boosted proteolytic cleavage of epithelial junction proteins and introduction of DNA double-strand breaks (DSBs) in host chromosomes, which co-operatively elicit malignant alterations. In addition, H. pylori genome-wide association studies (GWAS) identified several other SNPs potentially associated with increased gastric cancer (GC) risk. Here we discuss the clinical importance, evolutionary origin, and functional advantage of the H. pylori SNPs. These exciting new data highlight cancer-associated SNPs in bacteria, which should be explored in more detail in future studies.
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Affiliation(s)
- Bodo Linz
- Department of Biology, Division of Microbiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, 91058 Erlangen, Germany
| | - Heinrich Sticht
- Division of Bioinformatics, Institute of Biochemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg; 91054 Erlangen, Germany
| | - Nicole Tegtmeyer
- Department of Biology, Division of Microbiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, 91058 Erlangen, Germany
| | - Steffen Backert
- Department of Biology, Division of Microbiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstr. 5, 91058 Erlangen, Germany.
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2
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Kang SM, Kang HS, Chung WH, Kang KT, Kim DH. Structural Perspectives on Metal Dependent Roles of Ferric Uptake Regulator (Fur). Biomolecules 2024; 14:981. [PMID: 39199369 PMCID: PMC11353095 DOI: 10.3390/biom14080981] [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: 06/27/2024] [Revised: 07/27/2024] [Accepted: 08/03/2024] [Indexed: 09/01/2024] Open
Abstract
Iron is crucial for the metabolism and growth of most prokaryotic cells. The ferric uptake regulator (Fur) protein plays a central role in regulating iron homeostasis and metabolic processes in bacteria. It ensures the proper utilization of iron and the maintenance of cellular functions in response to environmental cues. Fur proteins are composed of an N-terminal DNA-binding domain (DBD) and a C-terminal dimerization domain (DD), typically existing as dimers in solution. Fur proteins have conserved metal-binding sites named S1, S2, and S3. Among them, site S2 serves as a regulatory site, and metal binding at S2 results in conformational changes. Additionally, as a transcriptional regulator, Fur specifically binds to a consensus DNA sequence called the Fur box. To elucidate the structural and functional properties of Fur proteins, various structures of metal- or DNA-bound Fur proteins or apo-Fur proteins have been determined. In this review, we focus on the structural properties of Fur proteins according to their ligand-bound state and the drug development strategies targeting Fur proteins. This information provides valuable insights for drug discovery.
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Affiliation(s)
- Sung-Min Kang
- College of Pharmacy, Duksung Women’s University, Seoul 01369, Republic of Korea; (S.-M.K.); (W.-H.C.); (K.-T.K.)
| | - Hoon-Seok Kang
- Interdisciplinary Graduate Program in Advanced Convergence Technology & Science, Jeju National University, Jeju 63243, Republic of Korea;
| | - Woo-Hyun Chung
- College of Pharmacy, Duksung Women’s University, Seoul 01369, Republic of Korea; (S.-M.K.); (W.-H.C.); (K.-T.K.)
| | - Kyu-Tae Kang
- College of Pharmacy, Duksung Women’s University, Seoul 01369, Republic of Korea; (S.-M.K.); (W.-H.C.); (K.-T.K.)
| | - Do-Hee Kim
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Sookmyung Women’s University, Seoul 04310, Republic of Korea
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3
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Vannini A, Pinatel E, Costantini PE, Pelliciari S, Roncarati D, Puccio S, De Bellis G, Scarlato V, Peano C, Danielli A. (Re)-definition of the holo- and apo-Fur direct regulons of Helicobacter pylori. J Mol Biol 2024; 436:168573. [PMID: 38626867 DOI: 10.1016/j.jmb.2024.168573] [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: 12/13/2023] [Revised: 04/09/2024] [Accepted: 04/10/2024] [Indexed: 04/28/2024]
Abstract
Iron homeostasis is a critical process for living organisms because this metal is an essential co-factor for fundamental biochemical activities, like energy production and detoxification, albeit its excess quickly leads to cell intoxication. The protein Fur (ferric uptake regulator) controls iron homeostasis in bacteria by switching from its apo- to holo-form as a function of the cytoplasmic level of ferrous ions, thereby modulating gene expression. The Helicobacter pylori HpFur protein has the rare ability to operate as a transcriptional commutator; apo- and holo-HpFur function as two different repressors with distinct DNA binding recognition properties for specific sets of target genes. Although the regulation of apo- and holo-HpFur in this bacterium has been extensively investigated, we propose a genome-wide redefinition of holo-HpFur direct regulon in H. pylori by integration of RNA-seq and ChIP-seq data, and a large extension of the apo-HpFur direct regulon. We show that in response to iron availability, new coding sequences, non-coding RNAs, toxin-antitoxin systems, and transcripts within open reading frames are directly regulated by apo- or holo-HpFur. These new targets and the more thorough validation and deeper characterization of those already known provide a complete and updated picture of the direct regulons of this two-faced transcriptional regulator.
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Affiliation(s)
- Andrea Vannini
- University of Bologna Department of Pharmacy and Biotechnology, Via Selmi 3, 40126 Bologna, Italy.
| | - Eva Pinatel
- Institute of Biomedical Technologies - National Research Council, Via Fratelli Cervi 93, 20054 Segrate (MI), Italy.
| | - Paolo Emidio Costantini
- University of Bologna Department of Pharmacy and Biotechnology, Via Selmi 3, 40126 Bologna, Italy.
| | - Simone Pelliciari
- Human Genetic Unit, Institute of Genetic and Cancer - University of Edinburgh, Crewe Road, Edinburgh EH4 2XU, UK.
| | - Davide Roncarati
- University of Bologna Department of Pharmacy and Biotechnology, Via Selmi 3, 40126 Bologna, Italy.
| | - Simone Puccio
- Institute of Genetics and Biomedical Research, UoS Milan - National Research Council, Via Manzoni 113, 20089 Rozzano (MI), Italy; Humanitas Clinical and Research Center, Via Manzoni 56, 20089 Rozzano (MI), Italy.
| | - Gianluca De Bellis
- Institute of Biomedical Technologies - National Research Council, Via Fratelli Cervi 93, 20054 Segrate (MI), Italy.
| | - Vincenzo Scarlato
- University of Bologna Department of Pharmacy and Biotechnology, Via Selmi 3, 40126 Bologna, Italy.
| | - Clelia Peano
- Institute of Genetics and Biomedical Research, UoS Milan - National Research Council, Via Manzoni 113, 20089 Rozzano (MI), Italy; Human Technopole, Via Rita Levi Montalcini 1, 20157 Milan, Italy.
| | - Alberto Danielli
- University of Bologna Department of Pharmacy and Biotechnology, Via Selmi 3, 40126 Bologna, Italy.
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4
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Zuo F, Somiah T, Gebremariam HG, Jonsson AB. Lactobacilli Downregulate Transcription Factors in Helicobacter pylori That Affect Motility, Acid Tolerance and Antimicrobial Peptide Survival. Int J Mol Sci 2022; 23:ijms232415451. [PMID: 36555092 PMCID: PMC9779568 DOI: 10.3390/ijms232415451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/22/2022] [Accepted: 11/24/2022] [Indexed: 12/13/2022] Open
Abstract
Helicobacter pylori infection triggers inflammation that may lead to gastritis, stomach ulcers and cancer. Probiotic bacteria, such as Lactobacillus, have been of interest as treatment options, however, little is known about the molecular mechanisms of Lactobacillus-mediated inhibition of H. pylori pathogenesis. In this work, we investigated the effect of Lactobacillus culture supernatants, so-called conditioned medium (CM), from two gastric isolates, L. gasseri and L. oris, on the expression of transcriptional regulators in H. pylori. Among the four known two-component systems (TCSs), i.e., ArsRS, FlgRS, CheAY and CrdRS, the flagellar regulator gene flgR and the acid resistance associated arsS gene were down-regulated by L. gasseri CM, whereas expression of the other TCS-genes remained unaffected. L. gasseri CM also reduced the motility of H. pylori, which is in line with reduced flgR expression. Furthermore, among six transcription factors of H. pylori only the ferric uptake regulator gene fur was regulated by L. gasseri CM. Deletion of fur further led to dramatically increased sensitivity to the antimicrobial peptide LL-37. Taken together, the results highlight that released/secreted factors of some lactobacilli, but not all, downregulate transcriptional regulators involved in motility, acid tolerance and LL-37 sensitivity of H. pylori.
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5
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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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Bacterial Membrane Vesicles as a Novel Strategy for Extrusion of Antimicrobial Bismuth Drug in Helicobacter pylori. mBio 2022; 13:e0163322. [PMID: 36154274 PMCID: PMC9601102 DOI: 10.1128/mbio.01633-22] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Bacterial antibiotic resistance is a major threat to human health. A combination of antibiotics with metals is among the proposed alternative treatments. Only one such combination is successfully used in clinics; it associates antibiotics with the metal bismuth to treat infections by Helicobacter pylori. This bacterial pathogen colonizes the human stomach and is associated with gastric cancer, killing 800,000 individuals yearly. The effect of bismuth in H. pylori treatment is not well understood in particular for sublethal doses such as those measured in the plasma of treated patients. We addressed this question and observed that bismuth induces the formation of homogeneously sized membrane vesicles (MVs) with unique protein cargo content enriched in bismuth-binding proteins, as shown by quantitative proteomics. Purified MVs of bismuth-exposed bacteria were strongly enriched in bismuth as measured by inductively coupled plasma optical emission spectrometry (ICP-OES), unlike bacterial cells from which they originate. Thus, our results revealed a novel function of MVs in bismuth detoxification, where secreted MVs act as tool to discard bismuth from the bacteria. Bismuth also induces the formation of intracellular polyphosphate granules that are associated with changes in nucleoid structure. Nucleoid compaction in response to bismuth was established by immunogold electron microscopy and refined by the first chromosome conformation capture (Hi-C) analysis of H. pylori. Our results reveal that even low doses of bismuth induce profound changes in H. pylori physiology and highlight a novel defense mechanism that involves MV-mediated bismuth extrusion from the bacteria and a probable local DNA protective response where polyphosphate granules are associated with nucleoid compaction.
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7
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Darmawan KK, Karagiannis TC, Hughes JG, Small DM, Hung A. Molecular modeling of lactoferrin for food and nutraceutical applications: insights from in silico techniques. Crit Rev Food Sci Nutr 2022; 63:9074-9097. [PMID: 35503258 DOI: 10.1080/10408398.2022.2067824] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Lactoferrin is a protein, primarily found in milk that has attracted the interest of the food industries due to its health properties. Nevertheless, the instability of lactoferrin has limited its commercial application. Recent studies have focused on encapsulation to enhance the stability of lactoferrin. However, the molecular insights underlying the changes of structural properties of lactoferrin and the interaction with protectants remain poorly understood. Computational approaches have proven useful in understanding the structural properties of molecules and the key binding with other constituents. In this review, comprehensive information on the structure and function of lactoferrin and the binding with various molecules for food purposes are reviewed, with a special emphasis on the use of molecular dynamics simulations. The results demonstrate the application of modeling and simulations to determine key residues of lactoferrin responsible for its stability and interactions with other biomolecular components under various conditions, which are also associated with its functional benefits. These have also been extended into the potential creation of enhanced lactoferrin for commercial purposes. This review provides valuable strategies in designing novel nutraceuticals for food science practitioners and those who have interests in acquiring familiarity with the application of computational modeling for food and health purposes.
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Affiliation(s)
- Kevion K Darmawan
- School of Science, STEM College, RMIT University, Melbourne, Australia
| | - Tom C Karagiannis
- Epigenomic Medicine, Department of Diabetes, Central Clinical School, Monash University, Melbourne, Australia
- Department of Clinical Pathology, The University of Melbourne, Melbourne, Australia
| | - Jeff G Hughes
- School of Science, STEM College, RMIT University, Melbourne, Australia
| | - Darryl M Small
- School of Science, STEM College, RMIT University, Melbourne, Australia
| | - Andrew Hung
- School of Science, STEM College, RMIT University, Melbourne, Australia
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8
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Tsang SH, Avilés-Santa ML, Abnet CC, Brito MO, Daviglus ML, Wassertheil-Smoller S, Castañeda SF, Minnerath S, Talavera GA, Graubard BI, Thyagarajan B, Camargo MC. Seroprevalence and Determinants of Helicobacter pylori Infection in the Hispanic Community Health Study/Study of Latinos. Clin Gastroenterol Hepatol 2022; 20:e438-e451. [PMID: 33667677 PMCID: PMC8410907 DOI: 10.1016/j.cgh.2021.02.042] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 02/22/2021] [Accepted: 02/26/2021] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Helicobacter pylori infection is the primary known risk factor for gastric cancer. Despite the global decline in H. pylori prevalence, this infection remains a major public health concern in developing areas, including Latin America. Our study aimed to determine H. pylori seroprevalence and identified its determinants among Hispanics/Latinos living in the United States (U.S.). METHODS The Hispanic Community Health Study/Study of Latinos (HCHS/SOL) is a population-based sample of self-identified Hispanics/Latinos (n = 16,144) in four U.S. communities, aged 18 to 74 years, recruited from randomly selected households using a stratified two-stage area probability sample design based on sampling households within sampled census block groups weighted for differential response rates. Anti-H. pylori immunoglobulin G antibodies were measured by an enzyme-linked immunosorbent assay using plasma samples. We calculated adjusted seroprevalence (i.e., predicted margins) from multivariable logistic regression models. RESULTS The overall weighted H. pylori seroprevalence was 57% among HCHS/SOL participants, with 38% and 62% seropositivity among U.S.-born and non-U.S.-born individuals, respectively. Age-adjusted prevalence varied by self-reported Hispanic/Latino background, ranging from 47% in Puerto Rican to 72% in Central American backgrounds. Adjusted H. pylori seroprevalence was higher in the following groups: older age, male sex, lower education, non-U.S. born status, smoking, greater number of missing teeth, fewer doctor visits, lower ferritin level, and hepatitis A seropositivity. CONCLUSIONS H. pylori seroprevalence in Hispanics/Latinos remains high and differed significantly by Hispanic/Latino background. H. pylori seropositivity is strongly associated with poor socioeconomic conditions. These findings highlight the ongoing importance of this bacterial infection in the U.S.
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Affiliation(s)
- Sabrina H Tsang
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, Maryland.
| | - M Larissa Avilés-Santa
- Division on Clinical and Health Services Research, National Institute on Health and Health Disparities, Rockville, Maryland
| | - Christian C Abnet
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, Maryland
| | - Maximo O Brito
- Division of Infectious Diseases, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Martha L Daviglus
- Institute for Minority Health Research, University of Illinois at Chicago, Chicago, Illinois
| | | | - Sheila F Castañeda
- Department of Psychology, San Diego State University, San Diego, California
| | - Sharon Minnerath
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, Minnesota
| | - Gregory A Talavera
- Department of Psychology, San Diego State University, San Diego, California
| | - Barry I Graubard
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, Maryland
| | - Bharat Thyagarajan
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, Minnesota
| | - M Constanza Camargo
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, Maryland
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9
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The Associations of Dietary Iron Intake and the Transferrin Receptor ( TFRC) rs9846149 Polymorphism with the Risk of Gastric Cancer: A Case-Control Study Conducted in Korea. Nutrients 2021; 13:nu13082600. [PMID: 34444760 PMCID: PMC8398449 DOI: 10.3390/nu13082600] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 07/21/2021] [Accepted: 07/26/2021] [Indexed: 12/20/2022] Open
Abstract
Background: A positive association between a high iron intake and colorectal cancer has been identified; however, the effect of dietary iron on gastric cancer (GC) remains unclear. Here, we investigate whether dietary iron is related to GC risk and whether the transferrin receptor (TFRC) rs9846149 polymorphism modifies this association. Methods: A case–control study was designed to assess this association among 374 GC patients and 754 healthy controls. A self-administered questionnaire was used to collect information on demographics, medical history and lifestyle. Dietary iron intake was assessed using a semi-quantitative food frequency questionnaire. TFRC rs9846149 was genetically analyzed using the Affymetrix Axiom Exom 319 Array platform. Results: A higher total dietary iron was significantly associated with decreased GC risk [OR = 0.65 (0.45–0.94), p for trend = 0.018]. A similar association was observed with nonheme iron [OR = 0.64 (0.44–0.92), p for trend = 0.018]. Individuals with a major allele of TFRC rs9846149 (CC/GC) and higher intake of total iron had a significantly lower GC risk than those with a lower intake [OR = 0.60 (0.41–0.88), p interaction = 0.035]. Conclusion: Our findings show the protective effects of total dietary iron, especially nonheme iron, against GC risk, and this association can be modified by TFRC rs9846149.
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Rueda-Robles A, Rubio-Tomás T, Plaza-Diaz J, Álvarez-Mercado AI. Impact of Dietary Patterns on H. pylori Infection and the Modulation of Microbiota to Counteract Its Effect. A Narrative Review. Pathogens 2021; 10:875. [PMID: 34358024 PMCID: PMC8308520 DOI: 10.3390/pathogens10070875] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 07/07/2021] [Accepted: 07/09/2021] [Indexed: 12/12/2022] Open
Abstract
Helicobacter pylori (H. pylori) is a Gram-negative bacterium that colonizes the stomach and can induce gastric disease and intra-gastric lesions, including chronic gastritis, peptic ulcers, gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma. This bacterium is responsible for long-term complications of gastric disease. The conjunction of host genetics, immune response, bacterial virulence expression, diet, micronutrient availability, and microbiome structure influence the disease outcomes related to chronic H. pylori infection. In this regard, the consumption of unhealthy and unbalanced diets can induce microbial dysbiosis, which infection with H. pylori may contribute to. However, to date, clinical trials have reported controversial results and current knowledge in this field is inconclusive. Here, we review preclinical studies concerning the changes produced in the microbiota that may be related to H. pylori infection, as well as the involvement of diet. We summarize and discuss the last approaches based on the modulation of the microbiota to improve the negative impact of H. pylori infection and their potential translation from bench to bedside.
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Affiliation(s)
- Ascensión Rueda-Robles
- Center of Biomedical Research, Institute of Nutrition and Food Technology “José Mataix”, University of Granada, Avda. del Conocimiento s/n., Armilla, 18016 Granada, Spain;
| | - Teresa Rubio-Tomás
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036 Barcelona, Spain;
- School of Medicine, University of Crete, 70013 Heraklion, Crete, Greece
| | - Julio Plaza-Diaz
- Children’s Hospital Eastern Ontario Research Institute, Ottawa, ON K1H 8L1, Canada;
- Department of Biochemistry and Molecular Biology II, School of Pharmacy, University of Granada, 18071 Granada, Spain
- Instituto de Investigación Biosanitaria ibs.GRANADA, Complejo Hospitalario Universitario de Granada, 18014 Granada, Spain
| | - Ana I. Álvarez-Mercado
- Center of Biomedical Research, Institute of Nutrition and Food Technology “José Mataix”, University of Granada, Avda. del Conocimiento s/n., Armilla, 18016 Granada, Spain;
- Department of Biochemistry and Molecular Biology II, School of Pharmacy, University of Granada, 18071 Granada, Spain
- Instituto de Investigación Biosanitaria ibs.GRANADA, Complejo Hospitalario Universitario de Granada, 18014 Granada, Spain
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Sánchez-Alonzo K, Silva-Mieres F, Arellano-Arriagada L, Parra-Sepúlveda C, Bernasconi H, Smith CT, Campos VL, García-Cancino A. Nutrient Deficiency Promotes the Entry of Helicobacter pylori Cells into Candida Yeast Cells. BIOLOGY 2021; 10:426. [PMID: 34065788 PMCID: PMC8151769 DOI: 10.3390/biology10050426] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/02/2021] [Accepted: 05/04/2021] [Indexed: 12/14/2022]
Abstract
Helicobacter pylori, a Gram-negative bacterium, has as a natural niche the human gastric epithelium. This pathogen has been reported to enter into Candida yeast cells; however, factors triggering this endosymbiotic relationship remain unknown. The aim of this work was to evaluate in vitro if variations in nutrient concentration in the cultured medium trigger the internalization of H. pylori within Candida cells. We used H. pylori-Candida co-cultures in Brucella broth supplemented with 1%, 5% or 20% fetal bovine serum or in saline solution. Intra-yeast bacteria-like bodies (BLBs) were observed using optical microscopy, while intra-yeast BLBs were identified as H. pylori using FISH and PCR techniques. Intra-yeast H. pylori (BLBs) viability was confirmed using the LIVE/DEAD BacLight Bacterial Viability kit. Intra-yeast H. pylori was present in all combinations of bacteria-yeast strains co-cultured. However, the percentages of yeast cells harboring bacteria (Y-BLBs) varied according to nutrient concentrations and also were strain-dependent. In conclusion, reduced nutrients stresses H. pylori, promoting its entry into Candida cells. The starvation of both H. pylori and Candida strains reduced the percentages of Y-BLBs, suggesting that starving yeast cells may be less capable of harboring stressed H. pylori cells. Moreover, the endosymbiotic relationship between H. pylori and Candida is dependent on the strains co-cultured.
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Affiliation(s)
- Kimberly Sánchez-Alonzo
- Laboratory of Bacterial Pathogenicity, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepcion, Concepción 4070386, Chile; (K.S.-A.); (F.S.-M.); (L.A.-A.); (C.P.-S.); (C.T.S.)
| | - Fabiola Silva-Mieres
- Laboratory of Bacterial Pathogenicity, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepcion, Concepción 4070386, Chile; (K.S.-A.); (F.S.-M.); (L.A.-A.); (C.P.-S.); (C.T.S.)
| | - Luciano Arellano-Arriagada
- Laboratory of Bacterial Pathogenicity, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepcion, Concepción 4070386, Chile; (K.S.-A.); (F.S.-M.); (L.A.-A.); (C.P.-S.); (C.T.S.)
| | - Cristian Parra-Sepúlveda
- Laboratory of Bacterial Pathogenicity, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepcion, Concepción 4070386, Chile; (K.S.-A.); (F.S.-M.); (L.A.-A.); (C.P.-S.); (C.T.S.)
| | | | - Carlos T. Smith
- Laboratory of Bacterial Pathogenicity, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepcion, Concepción 4070386, Chile; (K.S.-A.); (F.S.-M.); (L.A.-A.); (C.P.-S.); (C.T.S.)
| | - Víctor L. Campos
- Laboratory of Environmental Microbiology, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepción, Concepción 4070386, Chile;
| | - Apolinaria García-Cancino
- Laboratory of Bacterial Pathogenicity, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepcion, Concepción 4070386, Chile; (K.S.-A.); (F.S.-M.); (L.A.-A.); (C.P.-S.); (C.T.S.)
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12
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Klebba PE, Newton SMC, Six DA, Kumar A, Yang T, Nairn BL, Munger C, Chakravorty S. Iron Acquisition Systems of Gram-negative Bacterial Pathogens Define TonB-Dependent Pathways to Novel Antibiotics. Chem Rev 2021; 121:5193-5239. [PMID: 33724814 PMCID: PMC8687107 DOI: 10.1021/acs.chemrev.0c01005] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Iron is an indispensable metabolic cofactor in both pro- and eukaryotes, which engenders a natural competition for the metal between bacterial pathogens and their human or animal hosts. Bacteria secrete siderophores that extract Fe3+ from tissues, fluids, cells, and proteins; the ligand gated porins of the Gram-negative bacterial outer membrane actively acquire the resulting ferric siderophores, as well as other iron-containing molecules like heme. Conversely, eukaryotic hosts combat bacterial iron scavenging by sequestering Fe3+ in binding proteins and ferritin. The variety of iron uptake systems in Gram-negative bacterial pathogens illustrates a range of chemical and biochemical mechanisms that facilitate microbial pathogenesis. This document attempts to summarize and understand these processes, to guide discovery of immunological or chemical interventions that may thwart infectious disease.
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Affiliation(s)
- Phillip E Klebba
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - Salete M C Newton
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - David A Six
- Venatorx Pharmaceuticals, Inc., 30 Spring Mill Drive, Malvern, Pennsylvania 19355, United States
| | - Ashish Kumar
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - Taihao Yang
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - Brittany L Nairn
- Department of Biological Sciences, Bethel University, 3900 Bethel Drive, St. Paul, Minnesota 55112, United States
| | - Colton Munger
- Department of Biochemistry and Molecular Biophysics, Kansas State University, Manhattan, Kansas 66506, United States
| | - Somnath Chakravorty
- Jacobs School of Medicine and Biomedical Sciences, SUNY Buffalo, Buffalo, New York 14203, United States
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13
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Huang M, Liu M, Liu J, Zhu D, Tang Q, Jia R, Chen S, Zhao X, Yang Q, Wu Y, Zhang S, Huang J, Ou X, Mao S, Gao Q, Sun D, Wang M, Cheng A. Functional characterization of Fur in iron metabolism, oxidative stress resistance and virulence of Riemerella anatipestifer. Vet Res 2021; 52:48. [PMID: 33741064 PMCID: PMC7976709 DOI: 10.1186/s13567-021-00919-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 03/01/2021] [Indexed: 12/11/2022] Open
Abstract
Iron is essential for most bacteria to survive, but excessive iron leads to damage by the Fenton reaction. Therefore, the concentration of intracellular free iron must be strictly controlled in bacteria. Riemerella anatipestifer (R. anatipestifer), a Gram-negative bacterium, encodes the iron uptake system. However, the iron homeostasis mechanism remains largely unknown. In this study, it was shown that compared with the wild type R. anatipestifer CH-1, R. anatipestifer CH-1Δfur was more sensitive to streptonigrin, and this effect was alleviated when the bacteria were cultured in iron-depleted medium, suggesting that the fur mutant led to excess iron accumulation inside cells. Similarly, compared with R. anatipestifer CH-1∆recA, R. anatipestifer CH-1∆recAΔfur was more sensitive to H2O2-induced oxidative stress when the bacteria were grown in iron-rich medium rather than iron-depleted medium. Accordingly, it was shown that R. anatipestifer CH-1∆recAΔfur produced more intracellular ROS than R. anatipestifer CH-1∆recA in iron-rich medium. Electrophoretic mobility shift assays showed that R. anatipestifer CH-1 Fur suppressed the transcription of putative iron uptake genes through binding to their promoter regions. Finally, it was shown that compared with the wild type, R. anatipestifer CH-1Δfur was significantly attenuated in ducklings and that the colonization ability of R. anatipestifer CH-1Δfur in various tissues or organs was decreased. All these results suggested that Fur is important for iron homeostasis in R. anatipestifer and its pathogenic mechanism.
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Affiliation(s)
- Mi Huang
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Mafeng Liu
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Jiajun Liu
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Dekang Zhu
- Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Qianying Tang
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Renyong Jia
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Shun Chen
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Xinxin Zhao
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Qiao Yang
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Ying Wu
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Shaqiu Zhang
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Juan Huang
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Xumin Ou
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Sai Mao
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Qun Gao
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Di Sun
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China.,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China
| | - Mingshu Wang
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China. .,Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China. .,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China.
| | - Anchun Cheng
- Institute of Preventive Veterinary Medicine, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China. .,Research Centre of Avian Disease, College of Veterinary Medicine of Sichuan Agricultural University, Chengdu, 611130, Sichuan, China. .,Key Laboratory of Animal Disease and Human Health of Sichuan Province, Chengdu, 611130, Sichuan, China.
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14
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Carabotti M, Annibale B, Lahner E. Common Pitfalls in the Management of Patients with Micronutrient Deficiency: Keep in Mind the Stomach. Nutrients 2021; 13:nu13010208. [PMID: 33450823 PMCID: PMC7828248 DOI: 10.3390/nu13010208] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 12/31/2020] [Accepted: 01/08/2021] [Indexed: 02/05/2023] Open
Abstract
Micronutrient deficiencies are relatively common, in particular iron and cobalamin deficiency, and may potentially lead to life-threatening clinical consequences when not promptly recognized and treated, especially in elderly patients. The stomach plays an important role in the homeostasis of some important hematopoietic micronutrients like iron and cobalamin, and probably in others equally important such as ascorbic acid, calcium, and magnesium. A key role is played by the corpus oxyntic mucosa composed of parietal cells whose main function is gastric acid secretion and intrinsic factor production. Gastric acid secretion is necessary for the digestion and absorption of cobalamin and the absorption of iron, calcium, and probably magnesium, and is also essential for the absorption, secretion, and activation of ascorbic acid. Several pathological conditions such as Helicobacter pylori-related gastritis, corpus atrophic gastritis, as well as antisecretory drugs, and gastric surgery may interfere with the normal functioning of gastric oxyntic mucosa and micronutrients homeostasis. Investigation of the stomach by gastroscopy plus biopsies should always be considered in the management of patients with micronutrient deficiencies. The current review focuses on the physiological and pathophysiological aspects of gastric acid secretion and the role of the stomach in iron, cobalamin, calcium, and magnesium deficiency and ascorbate homeostasis.
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15
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Intracellular Presence of Helicobacter pylori and Its Virulence-Associated Genotypes within the Vaginal Yeast of Term Pregnant Women. Microorganisms 2021; 9:microorganisms9010131. [PMID: 33430099 PMCID: PMC7827377 DOI: 10.3390/microorganisms9010131] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 11/18/2020] [Accepted: 11/20/2020] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND
Helicobacter pylori transmission routes are not entirely elucidated. Since yeasts are postulated to transmit this pathogen, this study aimed to detect and genotype intracellular H. pylori harbored within vaginal yeast cells. METHODS A questionnaire was used to determine risk factors of H. pylori infection. Samples were seeded on Sabouraud Dextrose Agar and horse blood-supplemented Columbia agar. Isolated yeasts were identified using and observed by optical microscopy searching for intra-yeast H. pylori. Total yeast DNA, from one random sample, was extracted to search for H. pylori virulence genes by PCR and bacterial identification by sequencing. RESULTS 43% of samples contained yeasts, mainly Candida albicans (91%). Microscopy detected bacteria such as bodies and anti-H. pylori antibodies binding particles in 50% of the isolated yeasts. Total DNA extracted showed that 50% of the isolated yeasts were positive for H. pylori 16S rDNA and the sequence showed 99.8% similarity with H. pylori. In total, 32% of H. pylori DNA positive samples were cagA+ vacAs1a vacAm1 dupA-. No relationship was observed between possible H. pylori infection risk factors and vaginal yeasts harboring this bacterium. CONCLUSION
H. pylori having virulent genotypes were detected within vaginal yeasts constituting a risk for vertical transmission of this pathogen.
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16
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Martínez-Torró C, Torres-Puig S, Monge M, Sánchez-Alba L, González-Martín M, Marcos-Silva M, Perálvarez-Marín A, Canals F, Querol E, Piñol J, Pich OQ. Transcriptional response to metal starvation in the emerging pathogen Mycoplasma genitalium is mediated by Fur-dependent and -independent regulatory pathways. Emerg Microbes Infect 2019; 9:5-19. [PMID: 31859607 PMCID: PMC6968530 DOI: 10.1080/22221751.2019.1700762] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Transition metals participate in numerous enzymatic reactions and they are essential for survival in all living organisms. For this reason, bacterial pathogens have evolved dedicated machineries to effectively compete with their hosts and scavenge metals at the site of infection. In this study, we investigated the mechanisms controlling metal acquisition in the emerging human pathogen Mycoplasma genitalium. We observed a robust transcriptional response to metal starvation, and many genes coding for predicted lipoproteins and ABC-transporters were significantly up-regulated. Transcriptional analysis of a mutant strain lacking a metalloregulator of the Fur family revealed the activation of a full operon encoding a putative metal transporter system and a gene coding for a Histidine-rich lipoprotein (Hrl). We recognized a conserved sequence with dyad symmetry within the promoter region of the Fur-regulated genes. Mutagenesis of the predicted Fur operator within the hrl promoter abrogated Fur- and metal-dependent expression of a reporter gene. Metal starvation still impelled a strong transcriptional response in the fur mutant, demonstrating the existence of Fur-independent regulatory pathways controlling metal homeostasis. Finally, analysis of metal accumulation in the wild-type strain and the fur mutant by ICP-MS revealed an important role of Fur in nickel acquisition.
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Affiliation(s)
- Carlos Martínez-Torró
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Sergi Torres-Puig
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Marta Monge
- Vall d'Hebron Institute of Oncology (VHIO), Barcelona, Spain
| | - Lucía Sánchez-Alba
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Miguel González-Martín
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Marina Marcos-Silva
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Alex Perálvarez-Marín
- Biophysics Unit, Department of Biochemistry and Molecular Biology, School of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Francesc Canals
- Vall d'Hebron Institute of Oncology (VHIO), Barcelona, Spain
| | - Enrique Querol
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Jaume Piñol
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Oscar Q Pich
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Barcelona, Spain
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17
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Khajanchi BK, Xu J, Grim CJ, Ottesen AR, Ramachandran P, Foley SL. Global transcriptomic analyses of Salmonella enterica in Iron-depleted and Iron-rich growth conditions. BMC Genomics 2019; 20:490. [PMID: 31195964 PMCID: PMC6567447 DOI: 10.1186/s12864-019-5768-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 05/03/2019] [Indexed: 02/06/2023] Open
Abstract
Background Salmonella enterica possess several iron acquisition systems, encoded on the chromosome and plasmids. Recently, we demonstrated that incompatibility group (Inc) FIB plasmid-encoded iron acquisition systems (Sit and aerobactin) likely play an important role in persistence of Salmonella in human intestinal epithelial cells (Caco-2). In this study, we sought to determine global transcriptome analyses of S. enterica in iron-rich (IR) and iron-depleted (ID) growth conditions. Results The number of differentially-expressed genes were substantially higher for recipient (SE819) (n = 966) and transconjugant (TC) (n = 945) compared to the wild type (WT) (SE163A) (n = 110) strain in ID as compared to IR growth conditions. Several virulence-associated factors including T3SS, flagellin, cold-shock protein (cspE), and regulatory genes were upregulated in TC in ID compared to IR conditions. Whereas, IS1 and acrR/tetR transposases located on the IncFIB plasmid, ferritin and several regulatory genes were downregulated in TC in ID conditions. Enterobactin transporter (entS), iron ABC transporter (fepCD), colicin transporter, IncFIB-encoded enolase, cyclic di-GMP regulator (cdgR) and other regulatory genes of the WT strain were upregulated in ID compared to IR conditions. Conversely, ferritin, ferrous iron transport protein A (feoA), IncFIB-encoded IS1 and acrR/tetR transposases and ArtA toxin of WT were downregulated in ID conditions. SDS-PAGE coupled with LC-MS/MS analyses revealed that siderophore receptor proteins such as chromosomally-encoded IroN and, IncFIB-encoded IutA were upregulated in WT and TC in ID growth conditions. Both chromosome and IncFIB plasmid-encoded SitA was overexpressed in WT, but not in TC or recipient in ID conditions. Increased expression of flagellin was detected in recipient and TC, but not in WT in ID conditions. Conclusion Iron concentrations in growth media influenced differential gene expressions both at transcriptional and translational levels, including genes encoded on the IncFIB plasmid. Limited iron availability within the host may promote pathogenic Salmonella to differentially express subsets of genes encoded by chromosome and/or plasmids, facilitating establishment of successful infection. Electronic supplementary material The online version of this article (10.1186/s12864-019-5768-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Bijay K Khajanchi
- National Center for Toxicological Research, U. S. Food and Drug Administration, Jefferson, AR, USA.
| | - Joshua Xu
- National Center for Toxicological Research, U. S. Food and Drug Administration, Jefferson, AR, USA
| | - Christopher J Grim
- Center for Food Safety and Applied Nutrition, U. S. Food and Drug Administration, Laurel, MD, USA
| | - Andrea R Ottesen
- Center for Food Safety and Applied Nutrition, U. S. Food and Drug Administration, College Park, MD, USA
| | - Padmini Ramachandran
- Center for Food Safety and Applied Nutrition, U. S. Food and Drug Administration, College Park, MD, USA
| | - Steven L Foley
- National Center for Toxicological Research, U. S. Food and Drug Administration, Jefferson, AR, USA.
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18
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Thioredoxin H (TrxH) contributes to adversity adaptation and pathogenicity of Edwardsiella piscicida. Vet Res 2019; 50:26. [PMID: 30992061 PMCID: PMC6466703 DOI: 10.1186/s13567-019-0645-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 02/26/2019] [Indexed: 12/11/2022] Open
Abstract
Thioredoxins (Trxs) play an important role in defending against oxidative stress and keeping disulfide bonding correct to maintain protein function. Edwardsiella piscicida, a severe fish pathogen, has been shown to encode several thioredoxins including TrxA, TrxC, and TrxH, but their biological roles remain unknown. In this study, we characterized TrxH of E. piscicida (named TrxHEp) and examined its expression and function. TrxHEp is composed of 125 residues and possesses typical thioredoxin H motifs. Expression of trxHEp was upregulated under conditions of oxidative stress, iron starvation, low pH, and during infection of host cells. trxHEp expression was also regulated by ferric uptake regulator (Fur), an important global regulatory of E. piscicida. Compared to the wild type TX01, a markerless trxHEp in-frame mutant strain TX01∆trxH exhibited markedly compromised tolerance of the pathogen to hydrogen peroxide, acid stress, and iron deficiency. Deletion of trxHEp significantly retarded bacterial biofilm growth and decreased resistance against serum killing. Pathogenicity analysis shows that the inactivation of trxHEp significantly impaired the ability of E. piscicida to invade host cells, reproduce in macrophages, and infect host tissues. Introduction of a trans-expressed trxH gene restored the lost virulence of TX01∆trxH. There is likely to be a complex relationship of functional complementation or expression regulation between TrxH and another two thioredoxins, TrxA and TrxC, of E. piscicida. This is the first functional report of TrxH in fish pathogens, and the findings suggest that TrxHEp is essential for coping with adverse circumstances and contributes to host infection of E. piscicida.
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19
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Guo Y, Guan C, Wan H, Zhang Z, Li H, Sun H, Xia W. Inactivation of NikR from Helicobacter pylori by a bismuth drug. J Inorg Biochem 2019; 196:110685. [PMID: 30999221 DOI: 10.1016/j.jinorgbio.2019.03.025] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 03/21/2019] [Accepted: 03/28/2019] [Indexed: 01/18/2023]
Abstract
The NikR protein is an essential DNA regulator of Helicobacter pylori, a human pathogen, which infects almost half of the world's population. Herein, we comprehensively characterized the interaction of a bismuth drug with Helicobacter pylori NikR. We show that Bi(III) can occupy the high-affinity Ni(II) site of NikR. The highly-conserved residue Cys107 at this site is critical for Bi(III) binding. Importantly, such a binding disassembles physiologically functional NikR tetramer into inactive dimer, leading to abrogation of the DNA-binding capability of NikR. Bi(III)-binding also significantly disturbs regulatory function of Helicobacter pylori NikR in vivo. Therefore, NikR might serve as a potential intracellular target of a bismuth drug.
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Affiliation(s)
- Yu Guo
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou, China, 510275
| | - Chujun Guan
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou, China, 510275
| | - Heiyu Wan
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou, China, 510275
| | - Zhengrui Zhang
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou, China, 510275
| | - Hongyan Li
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Hongzhe Sun
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
| | - Wei Xia
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou, China, 510275.
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20
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Noto JM, Chopra A, Loh JT, Romero-Gallo J, Piazuelo MB, Watson M, Leary S, Beckett AC, Wilson KT, Cover TL, Mallal S, Israel DA, Peek RM. Pan-genomic analyses identify key Helicobacter pylori pathogenic loci modified by carcinogenic host microenvironments. Gut 2018; 67:1793-1804. [PMID: 28924022 PMCID: PMC5857411 DOI: 10.1136/gutjnl-2017-313863] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 06/30/2017] [Accepted: 07/15/2017] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Helicobacter pylori is the strongest risk factor for gastric cancer; however, the majority of infected individuals do not develop disease. Pathological outcomes are mediated by complex interactions among bacterial, host and environmental constituents, and two dietary factors linked with gastric cancer risk are iron deficiency and high salt. We hypothesised that prolonged adaptation of H. pylori to in vivo carcinogenic microenvironments results in genetic modification important for disease. DESIGN Whole genome sequencing of genetically related H. pylori strains that differ in virulence and targeted H. pylori sequencing following prolonged exposure of bacteria to in vitro carcinogenic conditions were performed. RESULTS A total of 180 unique single nucleotide polymorphisms (SNPs) were identified among the collective genomes when compared with a reference H. pylori genome. Importantly, common SNPs were identified in isolates harvested from iron-depleted and high salt carcinogenic microenvironments, including an SNP within fur (FurR88H). To investigate the direct role of low iron and/or high salt, H. pylori was continuously cultured in vitro under low iron or high salt conditions to assess fur genetic variation. Exposure to low iron or high salt selected for the FurR88H variant after only 5 days. To extend these results, fur was sequenced in 339 clinical H. pylori strains. Among the isolates examined, 17% (40/232) of strains isolated from patients with premalignant lesions harboured the FurR88H variant, compared with only 6% (6/107) of strains from patients with non-atrophic gastritis alone (p=0.0034). CONCLUSION These results indicate that specific genetic variation arises within H. pylori strains during in vivo adaptation to conditions conducive for gastric carcinogenesis.
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Affiliation(s)
- Jennifer M Noto
- Department of Medicine, Division of Gastroenterology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Abha Chopra
- Institute for Immunology and Infectious Diseases, Murdoch University, Murdoch, Australia
| | - John T Loh
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Judith Romero-Gallo
- Department of Medicine, Division of Gastroenterology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - M Blanca Piazuelo
- Department of Medicine, Division of Gastroenterology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Mark Watson
- Institute for Immunology and Infectious Diseases, Murdoch University, Murdoch, Australia
| | - Shay Leary
- Institute for Immunology and Infectious Diseases, Murdoch University, Murdoch, Australia
| | - Amber C Beckett
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Keith T Wilson
- Department of Medicine, Division of Gastroenterology, Vanderbilt University Medical Center, Nashville, Tennessee, USA,Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA,Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, Tennessee, USA,Department of Cancer Biology, 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 Veterans Affairs, Tennessee Valley Healthcare System, Nashville, Tennessee, USA,Department of Medicine, Division of Infectious Diseases, Vanderbilt University, Nashville, Tennessee, USA
| | - Simon Mallal
- Institute for Immunology and Infectious Diseases, Murdoch University, Murdoch, Australia,Department of Medicine, Division of Infectious Diseases, Vanderbilt University, Nashville, Tennessee, USA
| | - Dawn A Israel
- Department of Medicine, Division of Gastroenterology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Richard M Peek
- Department of Medicine, Division of Gastroenterology, Vanderbilt University Medical Center, Nashville, Tennessee, USA,Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA,Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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21
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Kell DB, Pretorius E. No effects without causes: the Iron Dysregulation and Dormant Microbes hypothesis for chronic, inflammatory diseases. Biol Rev Camb Philos Soc 2018; 93:1518-1557. [PMID: 29575574 PMCID: PMC6055827 DOI: 10.1111/brv.12407] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 02/12/2018] [Accepted: 02/15/2018] [Indexed: 12/11/2022]
Abstract
Since the successful conquest of many acute, communicable (infectious) diseases through the use of vaccines and antibiotics, the currently most prevalent diseases are chronic and progressive in nature, and are all accompanied by inflammation. These diseases include neurodegenerative (e.g. Alzheimer's, Parkinson's), vascular (e.g. atherosclerosis, pre-eclampsia, type 2 diabetes) and autoimmune (e.g. rheumatoid arthritis and multiple sclerosis) diseases that may appear to have little in common. In fact they all share significant features, in particular chronic inflammation and its attendant inflammatory cytokines. Such effects do not happen without underlying and initially 'external' causes, and it is of interest to seek these causes. Taking a systems approach, we argue that these causes include (i) stress-induced iron dysregulation, and (ii) its ability to awaken dormant, non-replicating microbes with which the host has become infected. Other external causes may be dietary. Such microbes are capable of shedding small, but functionally significant amounts of highly inflammagenic molecules such as lipopolysaccharide and lipoteichoic acid. Sequelae include significant coagulopathies, not least the recently discovered amyloidogenic clotting of blood, leading to cell death and the release of further inflammagens. The extensive evidence discussed here implies, as was found with ulcers, that almost all chronic, infectious diseases do in fact harbour a microbial component. What differs is simply the microbes and the anatomical location from and at which they exert damage. This analysis offers novel avenues for diagnosis and treatment.
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Affiliation(s)
- Douglas B. Kell
- School of ChemistryThe University of Manchester, 131 Princess StreetManchesterLancsM1 7DNU.K.
- The Manchester Institute of BiotechnologyThe University of Manchester, 131 Princess StreetManchesterLancsM1 7DNU.K.
- Department of Physiological SciencesStellenbosch University, Stellenbosch Private Bag X1Matieland7602South Africa
| | - Etheresia Pretorius
- Department of Physiological SciencesStellenbosch University, Stellenbosch Private Bag X1Matieland7602South Africa
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22
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Beckett AC, Loh JT, Chopra A, Leary S, Lin AS, McDonnell WJ, Dixon BREA, Noto JM, Israel DA, Peek RM, Mallal S, Algood HMS, Cover TL. Helicobacter pylori genetic diversification in the Mongolian gerbil model. PeerJ 2018; 6:e4803. [PMID: 29796347 PMCID: PMC5961626 DOI: 10.7717/peerj.4803] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 04/30/2018] [Indexed: 12/12/2022] Open
Abstract
Helicobacter pylori requires genetic agility to infect new hosts and establish long-term colonization of changing gastric environments. In this study, we analyzed H. pylori genetic adaptation in the Mongolian gerbil model. This model is of particular interest because H. pylori-infected gerbils develop a high level of gastric inflammation and often develop gastric adenocarcinoma or gastric ulceration. We analyzed the whole genome sequences of H. pylori strains cultured from experimentally infected gerbils, in comparison to the genome sequence of the input strain. The mean annualized single nucleotide polymorphism (SNP) rate per site was 1.5e−5, which is similar to the rates detected previously in H. pylori-infected humans. Many of the mutations occurred within or upstream of genes associated with iron-related functions (fur, tonB1, fecA2, fecA3, and frpB3) or encoding outer membrane proteins (alpA, oipA, fecA2, fecA3, frpB3 and cagY). Most of the SNPs within coding regions (86%) were non-synonymous mutations. Several deletion or insertion mutations led to disruption of open reading frames, suggesting that the corresponding gene products are not required or are deleterious during chronic H. pylori colonization of the gerbil stomach. Five variants (three SNPs and two deletions) were detected in isolates from multiple animals, which suggests that these mutations conferred a selective advantage. One of the mutations (FurR88H) detected in isolates from multiple animals was previously shown to confer increased resistance to oxidative stress, and we now show that this SNP also confers a survival advantage when H. pylori is co-cultured with neutrophils. Collectively, these analyses allow the identification of mutations that are positively selected during H. pylori colonization of the gerbil model.
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Affiliation(s)
- Amber C Beckett
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - John T Loh
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Abha Chopra
- Institute for Immunology and Infectious Diseases, Murdoch University, Murdoch, Australia
| | - Shay Leary
- Institute for Immunology and Infectious Diseases, Murdoch University, Murdoch, Australia
| | - Aung Soe Lin
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Wyatt J McDonnell
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Beverly R E A Dixon
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Jennifer M Noto
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Dawn A Israel
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Richard M Peek
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, United States of America.,Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America
| | - Simon Mallal
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, United States of America.,Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America.,Institute for Immunology and Infectious Diseases, Murdoch University, Murdoch, Australia
| | - Holly M Scott Algood
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America.,Tennessee Valley Healthcare System, Veterans Affairs, Nashville, TN, United States of America
| | - Timothy L Cover
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN, United States of America.,Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, United States of America.,Tennessee Valley Healthcare System, Veterans Affairs, Nashville, TN, United States of America
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23
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Abstract
Antibiotics have saved millions of lives over the past decades. However, the accumulation of so many antibiotic resistance genes by some clinically relevant pathogens has begun to lead to untreatable infections worldwide. The current antibiotic resistance crisis will require greater efforts by governments and the scientific community to increase the research and development of new antibacterial drugs with new mechanisms of action. A major challenge is the identification of novel microbial targets, essential for in vivo growth or pathogenicity, whose inhibitors can overcome the currently circulating resistome of human pathogens. In this article, we focus on the potential high value of bacterial transcriptional regulators as targets for the development of new antibiotics, discussing in depth the molecular role of these regulatory proteins in bacterial physiology and pathogenesis. Recent advances in the search for novel compounds that inhibit the biological activity of relevant transcriptional regulators in pathogenic bacteria are reviewed.
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24
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Zou DM, Sun WL. Reply to “Iron Overload and Hepatitis C Virus Infection”. Chin Med J (Engl) 2018; 131:252. [PMID: 29336381 PMCID: PMC5776863 DOI: 10.4103/0366-6999.222336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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25
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He X, Liao X, Li H, Xia W, Sun H. Bismuth-Induced Inactivation of Ferric Uptake Regulator from Helicobacter pylori. Inorg Chem 2017; 56:15041-15048. [DOI: 10.1021/acs.inorgchem.7b02380] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Xiaojun He
- MOE Key Laboratory
of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou 510275, China
| | - Xiangwen Liao
- MOE Key Laboratory
of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou 510275, China
| | - Hongyan Li
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, S.A.R, China
| | - Wei Xia
- MOE Key Laboratory
of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou 510275, China
| | - Hongzhe Sun
- MOE Key Laboratory
of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-sen University, Guangzhou 510275, China
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, S.A.R, China
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26
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Site-specific His/Asp phosphoproteomic analysis of prokaryotes reveals putative targets for drug resistance. BMC Microbiol 2017; 17:123. [PMID: 28545444 PMCID: PMC5445275 DOI: 10.1186/s12866-017-1034-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 05/15/2017] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Phosphorylation of amino acid residues on proteins is an important and common post-translational modification in both eukaryotes and prokaryotes. Most research work has been focused on phosphorylation of serine, threonine or tyrosine residues, whereas phosphorylation of other amino acids are significantly less clear due to the controversy on their stability under standard bioanalytical conditions. RESULTS Here we applied a shotgun strategy to analyze the histidine and aspartate phosphorylations in different microbes. Our results collectively indicate that histidine and aspartate phosphorylations frequently occur also in proteins that are not part of the two-component systems. Noticeably, a number of the modified proteins are pathogenesis-related or essential for survival in host. These include the zinc ion periplasmic transporter ZnuA in Acinetobacter baumannii SK17, the multidrug and toxic compound extrusion (MATE) channel YeeO in Klebsiella pneumoniae NTUH-K2044, branched amino acid transporter AzlC in Vibrio vulnificus and the RNA-modifying pseudouridine synthase in Helicobacter pylori. CONCLUSIONS In summary, histidine and aspartate phosphorylation is likely to be ubiquitous and to take place in proteins of various functions. This work also sheds light into how these functionally important proteins and potential drug targets might be regulated at a post-translational level.
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Feng J, Shi Q, Zhou G, Wang L, Chen A, Xie X, Huang X, Hu W. Improved production of poly-γ-glutamic acid with low molecular weight under high ferric ion concentration stress in Bacillus licheniformis ATCC 9945a. Process Biochem 2017. [DOI: 10.1016/j.procbio.2017.02.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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28
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Zepeda Gurrola RC, Fu Y, Rodríguez Luna IC, Benítez Cardoza CG, López López MDJ, López Vidal Y, Gutíerrez GRA, Rodríguez Pérez MA, Guo X. Novel protein interactions with an actin homolog (MreB) of Helicobacter pylori determined by bacterial two-hybrid system. Microbiol Res 2017; 201:39-45. [PMID: 28602400 DOI: 10.1016/j.micres.2017.04.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 03/24/2017] [Accepted: 04/22/2017] [Indexed: 02/06/2023]
Abstract
The bacterium Helicobacter pylori infects more than 50% of the world population and causes several gastroduodenal diseases, including gastric cancer. Nevertheless, we still need to explore some protein interactions that may be involved in pathogenesis. MreB, an actin homolog, showed some special characteristics in previous studies, indicating that it could have different functions. Protein functions could be realized via protein-protein interactions. In the present study, the MreB protein from H. pylori 26695 fused with two tags 10×His and GST in tandem was overexpressed and purified from Escherchia coli. The purified recombinant protein was used to perform a pull-down assay with H. pylori 26695 cell lysate. The pulled-down proteins were identified by mass spectrometry (MALDI-TOF), in which the known important proteins related to morphogenesis were absent but several proteins related to pathogenesis process were observed. The bacterial two-hybrid system was further used to evaluate the protein interactions and showed that new interactions of MreB respectively with VacA, UreB, HydB, HylB and AddA were confirmed but the interaction MreB-MreC was not validated. These results indicated that the protein MreB in H. pylori has a distinct interactome, does not participate in cell morphogenesis via MreB-MreC but could be related to pathogenesis.
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Affiliation(s)
| | - Yajuan Fu
- Centro de Biotecnología Genómica, Instituto Politécnico Nacional, Cd. Reynosa Tamaulipas, Mexico
| | | | | | | | - Yolanda López Vidal
- Facultad de Medicina, División de Investigación, Universidad Nacional Autónoma de Mexico
| | - Germán Rubén Aguilar Gutíerrez
- Centro de Investigación sobre Enfermedades Infecciosas, Instituto Nacional de Salud Pública, Cuernavaca, Morelos, Mexico
| | - Mario A Rodríguez Pérez
- Centro de Biotecnología Genómica, Instituto Politécnico Nacional, Cd. Reynosa Tamaulipas, Mexico
| | - Xianwu Guo
- Centro de Biotecnología Genómica, Instituto Politécnico Nacional, Cd. Reynosa Tamaulipas, Mexico.
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29
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De la Cruz MA, Ares MA, von Bargen K, Panunzi LG, Martínez-Cruz J, Valdez-Salazar HA, Jiménez-Galicia C, Torres J. Gene Expression Profiling of Transcription Factors of Helicobacter pylori under Different Environmental Conditions. Front Microbiol 2017; 8:615. [PMID: 28443084 PMCID: PMC5385360 DOI: 10.3389/fmicb.2017.00615] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 03/27/2017] [Indexed: 12/22/2022] Open
Abstract
Helicobacter pylori is a Gram-negative bacterium that colonizes the human gastric mucosa and causes peptic ulcers and gastric carcinoma. H. pylori strain 26695 has a small genome (1.67 Mb), which codes for few known transcriptional regulators that control bacterial metabolism and virulence. We analyzed by qRT-PCR the expression of 16 transcriptional regulators in H. pylori 26695, including the three sigma factors under different environmental conditions. When bacteria were exposed to acidic pH, urea, nickel, or iron, the sigma factors were differentially expressed with a particularly strong induction of fliA. The regulatory genes hrcA, hup, and crdR were highly induced in the presence of urea, nickel, and iron. In terms of biofilm formation fliA, flgR, hp1021, fur, nikR, and crdR were induced in sessile bacteria. Transcriptional expression levels of rpoD, flgR, hspR, hp1043, and cheY were increased in contact with AGS epithelial cells. Kanamycin, chloramphenicol, and tetracycline increased or decreased expression of regulatory genes, showing that these antibiotics affect the transcription of H. pylori. Our data indicate that environmental cues which may be present in the human stomach modulate H. pylori transcription.
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Affiliation(s)
- Miguel A De la Cruz
- Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias, Hospital de Pediatria, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro SocialMexico City, Mexico
| | - Miguel A Ares
- Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias, Hospital de Pediatria, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro SocialMexico City, Mexico
| | | | - Leonardo G Panunzi
- CNRS UMR7280, Inserm, U1104, Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2Marseille, France
| | - Jessica Martínez-Cruz
- Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias, Hospital de Pediatria, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro SocialMexico City, Mexico
| | - Hilda A Valdez-Salazar
- Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias, Hospital de Pediatria, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro SocialMexico City, Mexico
| | - César Jiménez-Galicia
- Laboratorio Clínico, Unidad Médica de Alta Especialidad, Hospital de Pediatría, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro SocialMexico City, Mexico
| | - Javier Torres
- Unidad de Investigación Médica en Enfermedades Infecciosas y Parasitarias, Hospital de Pediatria, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro SocialMexico City, Mexico
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30
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Hudak L, Jaraisy A, Haj S, Muhsen K. An updated systematic review and meta-analysis on the association between Helicobacter pylori infection and iron deficiency anemia. Helicobacter 2017; 22. [PMID: 27411077 DOI: 10.1111/hel.12330] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND We conducted an updated systematic review and meta-analysis to examine the prevalence of depleted iron stores among persons infected with Helicobacter pylori compared to uninfected ones. We also assessed the impact of anti-H. pylori eradication therapy plus iron therapy on ferritin and hemoglobin levels compared to iron therapy alone. METHODS A literature search was conducted using the databases Medline, the Cochrane Library, Cochrane Central Register of Controlled Trials, EMBASE, and the Science Citation Index Expanded. Observational studies with methodological quality score of 13 (median score) and above, on a scale of 0-16, and all randomized controlled trials (RCTs) were eligible for the meta-analyses. Pooled point estimates and 95% confidence intervals (CI) were obtained using the random effects model. RESULTS Compared to uninfected persons, H. pylori-infected individuals showed increased likelihood of iron deficiency anemia (14 observational studies); pooled OR 1.72 (95% CI 1.23-2.42); iron deficiency (pooled OR 1.33; 95% CI 1.15-1.54; 30 studies); and anemia (pooled OR 1.15; 95% CI 1.00-1.32; 23 studies). Meta-analyses of seven RCTs showed increased ferritin, standardized mean difference (SMD) 0.53 (95% 0.21-0.85), but not hemoglobin, SMD 0.36 (95% -0.07 to 0.78), Pv=.1, following anti-H. pylori eradication therapy plus iron therapy as compared with iron therapy alone. Significant heterogeneity was found among studies, as well as evidence of publication bias. CONCLUSIONS Current evidence indicates increased likelihood of depleted iron stores in relation to H. pylori infection. H. pylori eradication therapy, added to iron therapy, might be beneficial in increasing ferritin and hemoglobin levels.
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Affiliation(s)
- Lauren Hudak
- Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ameen Jaraisy
- Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Saeda Haj
- Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Khitam Muhsen
- Department of Epidemiology and Preventive Medicine, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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31
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Whitmire JM, Merrell DS. Use of Random and Site-Directed Mutagenesis to Probe Protein Structure-Function Relationships: Applied Techniques in the Study of Helicobacter pylori. Methods Mol Biol 2017; 1498:461-480. [PMID: 27709595 DOI: 10.1007/978-1-4939-6472-7_31] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Mutagenesis is a valuable tool to examine the structure-function relationships of bacterial proteins. As such, a wide variety of mutagenesis techniques and strategies have been developed. This chapter details a selection of random mutagenesis methods and site-directed mutagenesis procedures that can be applied to an array of bacterial species. Additionally, the direct application of the techniques to study the Helicobacter pylori Ferric Uptake Regulator (Fur) protein is described. The varied approaches illustrated herein allow the robust investigation of the structural-functional relationships within a protein of interest.
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Affiliation(s)
- Jeannette M Whitmire
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD, 20814, USA
| | - D Scott Merrell
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD, 20814, USA.
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32
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Dietary Composition Influences Incidence of Helicobacter pylori-Induced Iron Deficiency Anemia and Gastric Ulceration. Infect Immun 2016; 84:3338-3349. [PMID: 27620719 DOI: 10.1128/iai.00479-16] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 09/02/2016] [Indexed: 12/17/2022] Open
Abstract
Epidemiologic studies have provided conflicting data regarding an association between Helicobacter pylori infection and iron deficiency anemia (IDA) in humans. Here, a Mongolian gerbil model was used to investigate a potential role of H. pylori infection, as well as a possible role of diet, in H. pylori-associated IDA. Mongolian gerbils (either H. pylori infected or uninfected) received a normal diet or one of three diets associated with increased H. pylori virulence: high-salt, low-iron, or a combination of a high-salt and low-iron diet. In an analysis of all infected animals compared to uninfected animals (independent of diet), H. pylori-infected gerbils had significantly lower hemoglobin values than their uninfected counterparts at 16 weeks postinfection (P < 0.0001). The mean corpuscular volume (MCV) and serum ferritin values were significantly lower in H. pylori-infected gerbils than in uninfected gerbils, consistent with IDA. Leukocytosis and thrombocytosis were also detected in infected gerbils, indicating the presence of a systemic inflammatory response. In comparison to uninfected gerbils, H. pylori-infected gerbils had a higher gastric pH, a higher incidence of gastric ulcers, and a higher incidence of fecal occult blood loss. Anemia was associated with the presence of gastric ulceration but not gastric cancer. Infected gerbils consuming diets with a high salt content developed gastric ulcers significantly more frequently than gerbils consuming a normal-salt diet, and the lowest hemoglobin levels were in infected gerbils consuming a high-salt/low-iron diet. These data indicate that H. pylori infection can cause IDA and that the composition of the diet influences the incidence and severity of H. pylori-induced IDA.
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33
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Mathieu S, Cissé C, Vitale S, Ahmadova A, Degardin M, Pérard J, Colas P, Miras R, Boturyn D, Covès J, Crouzy S, Michaud-Soret I. From Peptide Aptamers to Inhibitors of FUR, Bacterial Transcriptional Regulator of Iron Homeostasis and Virulence. ACS Chem Biol 2016; 11:2519-28. [PMID: 27409249 DOI: 10.1021/acschembio.6b00360] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
FUR (Ferric Uptake Regulator) protein is a global transcriptional regulator that senses iron status and controls the expression of genes involved in iron homeostasis, virulence, and oxidative stress. Ubiquitous in Gram-negative bacteria and absent in eukaryotes, FUR is an attractive antivirulence target since the inactivation of the fur gene in various pathogens attenuates their virulence. The characterization of 13-aa-long anti-FUR linear peptides derived from the variable part of the anti-FUR peptide aptamers, that were previously shown to decrease pathogenic E. coli strain virulence in a fly infection model, is described herein. Modeling, docking, and experimental approaches in vitro (activity and interaction assays, mutations) and in cells (yeast two-hybrid assays) were combined to characterize the interactions of the peptides with FUR, and to understand their mechanism of inhibition. As a result, reliable structure models of two peptide-FUR complexes are given. Inhibition sites are mapped in the groove between the two FUR subunits where DNA should also bind. Another peptide behaves differently and interferes with the dimerization itself. These results define these novel small peptide inhibitors as lead compounds for inhibition of the FUR transcription factor.
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Affiliation(s)
- Sophie Mathieu
- CNRS,
Laboratoire
de Chimie et Biologie des Métaux (LCBM) UMR 5249 CNRS-CEA-UJF, F-38054 Grenoble, France
- CEA, LCBM, F-38054 Grenoble, France
- Univ. Grenoble Alpes,
LCBM, F-38054 Grenoble, France
| | - Cheickna Cissé
- CNRS,
Laboratoire
de Chimie et Biologie des Métaux (LCBM) UMR 5249 CNRS-CEA-UJF, F-38054 Grenoble, France
- CEA, LCBM, F-38054 Grenoble, France
- Univ. Grenoble Alpes,
LCBM, F-38054 Grenoble, France
| | - Sylvia Vitale
- CNRS,
Laboratoire
de Chimie et Biologie des Métaux (LCBM) UMR 5249 CNRS-CEA-UJF, F-38054 Grenoble, France
- CEA, LCBM, F-38054 Grenoble, France
- Univ. Grenoble Alpes,
LCBM, F-38054 Grenoble, France
| | - Aynur Ahmadova
- CNRS,
Laboratoire
de Chimie et Biologie des Métaux (LCBM) UMR 5249 CNRS-CEA-UJF, F-38054 Grenoble, France
- CEA, LCBM, F-38054 Grenoble, France
- Univ. Grenoble Alpes,
LCBM, F-38054 Grenoble, France
| | - Mélissa Degardin
- CNRS,
Laboratoire
de Chimie et Biologie des Métaux (LCBM) UMR 5249 CNRS-CEA-UJF, F-38054 Grenoble, France
- CEA, LCBM, F-38054 Grenoble, France
- Univ. Grenoble Alpes,
LCBM, F-38054 Grenoble, France
- Univ. Grenoble
Alpes, DCM UMR 5250, F-38000 Grenoble, France
- CNRS, DCM UMR
5250, F-38000 Grenoble, France
| | - Julien Pérard
- CNRS,
Laboratoire
de Chimie et Biologie des Métaux (LCBM) UMR 5249 CNRS-CEA-UJF, F-38054 Grenoble, France
- CEA, LCBM, F-38054 Grenoble, France
- Univ. Grenoble Alpes,
LCBM, F-38054 Grenoble, France
| | - Pierre Colas
- P2I2 Group, Protein Phosphorylation
and Human Disease Unit, CNRS Unité de Service et de Recherche
USR3151, Station Biologique de Roscoff, F-29680 Roscoff, France
| | - Roger Miras
- CNRS,
Laboratoire
de Chimie et Biologie des Métaux (LCBM) UMR 5249 CNRS-CEA-UJF, F-38054 Grenoble, France
- CEA, LCBM, F-38054 Grenoble, France
- Univ. Grenoble Alpes,
LCBM, F-38054 Grenoble, France
| | - Didier Boturyn
- Univ. Grenoble
Alpes, DCM UMR 5250, F-38000 Grenoble, France
- CNRS, DCM UMR
5250, F-38000 Grenoble, France
| | - Jacques Covès
- Univ. Grenoble
Alpes, IBS, F-38044 Grenoble, France
- CNRS, IBS, F-38044 Grenoble, France
- CEA, IBS, F-38044 Grenoble, France
| | - Serge Crouzy
- CNRS,
Laboratoire
de Chimie et Biologie des Métaux (LCBM) UMR 5249 CNRS-CEA-UJF, F-38054 Grenoble, France
- CEA, LCBM, F-38054 Grenoble, France
- Univ. Grenoble Alpes,
LCBM, F-38054 Grenoble, France
| | - Isabelle Michaud-Soret
- CNRS,
Laboratoire
de Chimie et Biologie des Métaux (LCBM) UMR 5249 CNRS-CEA-UJF, F-38054 Grenoble, France
- CEA, LCBM, F-38054 Grenoble, France
- Univ. Grenoble Alpes,
LCBM, F-38054 Grenoble, France
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Wang Y, Tsang CN, Xu F, Kong PW, Hu L, Wang J, Chu IK, Li H, Sun H. Bio-coordination of bismuth in Helicobacter pylori revealed by immobilized metal affinity chromatography. Chem Commun (Camb) 2016; 51:16479-82. [PMID: 26391105 DOI: 10.1039/c5cc04958j] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Over 300 Bi-binding peptides from 166 proteins in H. pylori were identified by Bi-IMAC. Bi(3+) exhibits high selectivity towards peptide enriched by cysteines and histidines with dominated motif patterns of CXnC, CXnH and HXnH. Structural rationalization and functional categorization on the identified Bi-binding peptides and proteins provide an insight into the inhibitory action of bismuth drugs.
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Affiliation(s)
- Yuchuan Wang
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.
| | - Cheuk-Nam Tsang
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.
| | - Feng Xu
- Centre for Genomic Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China
| | - Pak-Wing Kong
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.
| | - Ligang Hu
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.
| | - Junwen Wang
- Centre for Genomic Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China
| | - Ivan Keung Chu
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.
| | - Hongyan Li
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.
| | - Hongzhe Sun
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.
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Pérard J, Covès J, Castellan M, Solard C, Savard M, Miras R, Galop S, Signor L, Crouzy S, Michaud-Soret I, de Rosny E. Quaternary Structure of Fur Proteins, a New Subfamily of Tetrameric Proteins. Biochemistry 2016; 55:1503-15. [DOI: 10.1021/acs.biochem.5b01061] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Julien Pérard
- CNRS, Laboratoire de Chimie et Biologie
des Métaux
(LCBM), UMR 5249, CNRS-CEA-UJF, F-38054 Grenoble, France
- CEA, LCBM, F-38054 Grenoble, France
- Univ. Grenoble Alpes, LCBM, F-38054 Grenoble, France
| | - Jacques Covès
- Univ. Grenoble Alpes, IBS, F-38044 Grenoble, France
- CNRS, IBS, F-38044 Grenoble, France
- CEA, IBS, F-38044 Grenoble, France
| | - Mathieu Castellan
- Univ. Grenoble Alpes, IBS, F-38044 Grenoble, France
- CNRS, IBS, F-38044 Grenoble, France
- CEA, IBS, F-38044 Grenoble, France
| | - Charles Solard
- Univ. Grenoble Alpes, IBS, F-38044 Grenoble, France
- CNRS, IBS, F-38044 Grenoble, France
- CEA, IBS, F-38044 Grenoble, France
| | - Myriam Savard
- Univ. Grenoble Alpes, IBS, F-38044 Grenoble, France
- CNRS, IBS, F-38044 Grenoble, France
- CEA, IBS, F-38044 Grenoble, France
| | - Roger Miras
- CNRS, Laboratoire de Chimie et Biologie
des Métaux
(LCBM), UMR 5249, CNRS-CEA-UJF, F-38054 Grenoble, France
- CEA, LCBM, F-38054 Grenoble, France
- Univ. Grenoble Alpes, LCBM, F-38054 Grenoble, France
| | - Sandra Galop
- CNRS, Laboratoire de Chimie et Biologie
des Métaux
(LCBM), UMR 5249, CNRS-CEA-UJF, F-38054 Grenoble, France
- CEA, LCBM, F-38054 Grenoble, France
- Univ. Grenoble Alpes, LCBM, F-38054 Grenoble, France
| | - Luca Signor
- Univ. Grenoble Alpes, IBS, F-38044 Grenoble, France
- CNRS, IBS, F-38044 Grenoble, France
- CEA, IBS, F-38044 Grenoble, France
| | - Serge Crouzy
- CNRS, Laboratoire de Chimie et Biologie
des Métaux
(LCBM), UMR 5249, CNRS-CEA-UJF, F-38054 Grenoble, France
- CEA, LCBM, F-38054 Grenoble, France
- Univ. Grenoble Alpes, LCBM, F-38054 Grenoble, France
| | - Isabelle Michaud-Soret
- CNRS, Laboratoire de Chimie et Biologie
des Métaux
(LCBM), UMR 5249, CNRS-CEA-UJF, F-38054 Grenoble, France
- CEA, LCBM, F-38054 Grenoble, France
- Univ. Grenoble Alpes, LCBM, F-38054 Grenoble, France
| | - Eve de Rosny
- Univ. Grenoble Alpes, IBS, F-38044 Grenoble, France
- CNRS, IBS, F-38044 Grenoble, France
- CEA, IBS, F-38044 Grenoble, France
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36
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Expansion of the tetracycline-dependent regulation toolbox for Helicobacter pylori. Appl Environ Microbiol 2015; 81:7969-80. [PMID: 26362986 DOI: 10.1128/aem.02191-15] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 09/01/2015] [Indexed: 01/19/2023] Open
Abstract
In an effort to gain greater understanding of the biology and infection processes of Helicobacter pylori, we have expanded the functionality of the tetracycline-dependent gene regulation (tet) system to provide more improved and versatile genetic control and facilitate the generation of conditional mutants to study essential genes. Second-generation tetracycline-responsive H. pylori uPtetO5 promoters were based on the mutated core ureA promoter. Single point mutations at either the ribosomal binding site or the start codon were introduced to shift the regulatory range of three uPtetO5 derivatives. All promoters were tested for regulation by TetR and revTetR using dapD, a gene essential to peptidoglycan biosynthesis, as a reporter. All tet promoters were effectively regulated by both TetR and revTetR, and their regulation windows overlapped so as to cover a broad range of expression levels. tet promoters uPtetO5m1 and uPtetO5m2 could be sufficiently silenced by both TetR and revTetR so that the conditional mutants could not grow in the absence of diaminopimelic acid (DAP). Furthermore, through the use of these inducible promoters, we reveal that insufficient DAP biosynthesis results in viable cells with altered morphology. Overall, the development and optimization of tet regulation for H. pylori will not only permit the study of essential genes but also facilitate investigations into gene dosage effects on H. pylori physiology.
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Hung CL, Cheng HH, Hsieh WC, Tsai ZTY, Tsai HK, Chu CH, Hsieh WP, Chen YF, Tsou Y, Lai CH, Wang WC. The CrdRS two-component system in Helicobacter pylori responds to nitrosative stress. Mol Microbiol 2015; 97:1128-41. [PMID: 26082024 DOI: 10.1111/mmi.13089] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/09/2015] [Indexed: 11/28/2022]
Abstract
Helicobacter pylori inhabits the gastric mucosa where it senses and responds to various stresses via a two-component systems (TCSs) that enable its persistent colonization. The aim of this study was to investigate whether any of the three paired TCSs (ArsRS, FleRS and CrdRS) in H. pylori respond to nitrosative stress. The results showed that the expression of crdS was significantly increased upon exposure to nitric oxide (NO). crdS-knockout (ΔcrdS) and crdR/crdS-knockout (ΔcrdRS) H. pylori, but not arsS-knockout (ΔarsS) or fleS-knockout (ΔfleS) H. pylori, showed a significant loss of viability upon exposure to NO compared with wild-type strain. Knockin crdS (ΔcrdS-in) significantly restored viability in the presence of NO. Global transcriptional profiling analysis of wild-type and ΔcrdS H. pylori in the presence or absence of NO showed that 101 genes were differentially expressed, including copper resistance determinant A (crdA), transport, binding and envelope proteins. The CrdR binding motifs were investigated by competitive electrophoretic mobility shift assay, which revealed that the two AC-rich regions in the crdA promoter region are required for binding. These results demonstrate that CrdR-crdA interaction enables H. pylori to survive under nitrosative stress.
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Affiliation(s)
- Chiu-Lien Hung
- Department of Biochemistry and Molecular Medicine, University of California Davis Comprehensive Cancer Center, Sacramento, California, USA.,Institute of Molecular and Cellular Biology & Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Hsin-Hung Cheng
- Institute of Molecular and Cellular Biology & Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Wan-Chen Hsieh
- Institute of Molecular and Cellular Biology & Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Zing Tsung-Yeh Tsai
- Bioinformatics Program, Taiwan International Graduate Program, Academia Sinica, Taipei, Taiwan
| | - Huai-Kuang Tsai
- Bioinformatics Program, Taiwan International Graduate Program, Academia Sinica, Taipei, Taiwan
| | - Chia-Han Chu
- Biomedical Science and Engineering Center, National Tsing Hua University, Hsinchu, Taiwan
| | - Wen-Ping Hsieh
- Institute of Statistics, National Tsing Hua University, Hsinchu, Taiwan
| | - Yi-Fan Chen
- Institute of Molecular and Cellular Biology & Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Yu Tsou
- Institute of Molecular and Cellular Biology & Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Chih-Ho Lai
- Department of Nursing, Asia University, Taichung, Taiwan.,Graduate Institute of Basic Medical Science, School of Medicine, China Medical University, Taichung, Taiwan.,Department of Microbiology and Immunology, Chang Gung University, Taoyuan, Taiwan
| | - Wen-Ching Wang
- Institute of Molecular and Cellular Biology & Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan.,Biomedical Science and Engineering Center, National Tsing Hua University, Hsinchu, Taiwan
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38
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Interplay between iron homeostasis and virulence: Fur and RyhB as major regulators of bacterial pathogenicity. Vet Microbiol 2015; 179:2-14. [PMID: 25888312 DOI: 10.1016/j.vetmic.2015.03.024] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 03/23/2015] [Accepted: 03/25/2015] [Indexed: 11/21/2022]
Abstract
In bacteria-host interactions, competition for iron is critical for the outcome of the infection. As a result of its redox properties, this metal is essential for the growth and proliferation of most living organisms, including pathogenic bacteria. This metal is also potentially toxic, making the precise maintenance of iron homeostasis necessary for survival. Iron acquisition and storage control is mediated in most bacteria by the global ferric uptake regulator (Fur) and iron-responsive small regulatory non-coding RNAs (RyhB in the model organism Escherichia coli). While the role of these regulators in iron homeostasis is well documented in both pathogenic and non-pathogenic bacteria, many recent studies also demonstrate that these regulators are involved in the virulence of pathogenic bacteria. By sensing iron availability in the environment, Fur and RyhB are able to regulate, either directly or indirectly via other transcriptional regulators or modulation of intracellular iron concentration, many virulence determinants of pathogenic bacteria. Iron is thus both a nutritional and regulatory element, allowing bacteria to adapt to various host environments by adjusting expression of virulence factors. In this review, we present evidences that Fur and RyhB are the major regulators of this adaptation, as they are involved in diverse functions ranging from iron homeostasis to regulation of virulence by mediating key pathogen responses such as invasion of eukaryotic cells, toxin production, motility, quorum sensing, stress resistance or biofilm formation. Therefore, Fur and RyhB play a major role in regulating an adaptative response during bacterial infections, making them important targets in the fight against pathogenic bacteria.
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39
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Cissé C, Mathieu SV, Abeih MBO, Flanagan L, Vitale S, Catty P, Boturyn D, Michaud-Soret I, Crouzy S. Inhibition of the ferric uptake regulator by peptides derived from anti-FUR peptide aptamers: coupled theoretical and experimental approaches. ACS Chem Biol 2014; 9:2779-86. [PMID: 25238402 DOI: 10.1021/cb5005977] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The FUR protein (ferric uptake regulator) is an iron-dependent global transcriptional regulator. Specific to bacteria, FUR is an attractive antibacterial target since virulence is correlated to iron bioavailability. Recently, four anti-FUR peptide aptamers, composed of 13 amino acid variable loops inserted into a thioredoxinA scaffold, were identified, which were able to interact with Escherichia coli FUR (EcFUR), inhibit its binding to DNA and to decrease the virulence of pathogenic E. coli in a fly infection model. The first characterization of anti-FUR linear peptides (pF1 6 to 13 amino acids) derived from the variable part of the F1 anti-FUR peptide aptamer is described herein. Theoretical and experimental approaches, in original combination, were used to study interactions of these peptides with FUR in order to understand their mechanism of inhibition. After modeling EcFUR by homology, docking with Autodock was combined with molecular dynamics simulations in implicit solvent to take into account the flexibility of the partners. All calculations were cross-checked either with other programs or with experimental data. As a result, reliable structures of EcFUR and its complex with pF1 are given and an inhibition pocket formed by the groove between the two FUR subunits is proposed. The location of the pocket was validated through experimental mutation of key EcFUR residues at the site of proposed peptide interaction. Cyclisation of pF1, mimicking the peptide constraint in F1, improved inhibition. The details of the interactions between peptide and protein were analyzed and a mechanism of inhibition of these anti-FUR molecules is proposed.
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Affiliation(s)
- Cheickna Cissé
- CEA, Laboratoire
de Chimie et Biologie des Métaux
(LCBM), F-38000 Grenoble, France
- CNRS, LCBM, F-38000 Grenoble, France
- Univ. Grenoble Alpes, LCBM, F-38000 Grenoble, France
| | - Sophie V. Mathieu
- CEA, Laboratoire
de Chimie et Biologie des Métaux
(LCBM), F-38000 Grenoble, France
- CNRS, LCBM, F-38000 Grenoble, France
- Univ. Grenoble Alpes, LCBM, F-38000 Grenoble, France
| | - Mohamed B. Ould Abeih
- CEA, Laboratoire
de Chimie et Biologie des Métaux
(LCBM), F-38000 Grenoble, France
- CNRS, LCBM, F-38000 Grenoble, France
- Univ. Grenoble Alpes, LCBM, F-38000 Grenoble, France
| | - Lindsey Flanagan
- CEA, Laboratoire
de Chimie et Biologie des Métaux
(LCBM), F-38000 Grenoble, France
- CNRS, LCBM, F-38000 Grenoble, France
- Univ. Grenoble Alpes, LCBM, F-38000 Grenoble, France
| | - Sylvia Vitale
- CEA, Laboratoire
de Chimie et Biologie des Métaux
(LCBM), F-38000 Grenoble, France
- CNRS, LCBM, F-38000 Grenoble, France
- Univ. Grenoble Alpes, LCBM, F-38000 Grenoble, France
| | - Patrice Catty
- CEA, Laboratoire
de Chimie et Biologie des Métaux
(LCBM), F-38000 Grenoble, France
- CNRS, LCBM, F-38000 Grenoble, France
- Univ. Grenoble Alpes, LCBM, F-38000 Grenoble, France
| | - Didier Boturyn
- Univ. Grenoble Alpes, DCM, CRNS, UMR 5250, F-38000 Grenoble, France
| | - Isabelle Michaud-Soret
- CEA, Laboratoire
de Chimie et Biologie des Métaux
(LCBM), F-38000 Grenoble, France
- CNRS, LCBM, F-38000 Grenoble, France
- Univ. Grenoble Alpes, LCBM, F-38000 Grenoble, France
| | - Serge Crouzy
- CEA, Laboratoire
de Chimie et Biologie des Métaux
(LCBM), F-38000 Grenoble, France
- CNRS, LCBM, F-38000 Grenoble, France
- Univ. Grenoble Alpes, LCBM, F-38000 Grenoble, France
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40
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Abstract
Although the composition of the gut microbiota and its symbiotic contribution to key host physiological functions are well established, little is known as yet about the bacterial factors that account for this symbiosis. We selected Lactobacillus casei as a model microorganism to proceed to genomewide identification of the functions required for a symbiont to establish colonization in the gut. As a result of our recent development of a transposon-mutagenesis tool that overcomes the barrier that had prevented L. casei random mutagenesis, we developed a signature-tagged mutagenesis approach combining whole-genome reverse genetics using a set of tagged transposons and in vivo screening using the rabbit ligated ileal loop model. After sequencing transposon insertion sites in 9,250 random mutants, we assembled a library of 1,110 independent mutants, all disrupted in a different gene, that provides a representative view of the L. casei genome. By determining the relative quantity of each of the 1,110 mutants before and after the in vivo challenge, we identified a core of 47 L. casei genes necessary for its establishment in the gut. They are involved in housekeeping functions, metabolism (sugar, amino acids), cell wall biogenesis, and adaptation to environment. Hence we provide what is, to our knowledge, the first global functional genomics analysis of L. casei symbiosis.
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41
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McClain MS, Duncan SS, Gaddy JA, Cover TL. Control of gene expression in Helicobacter pylori using the Tet repressor. J Microbiol Methods 2013; 95:336-41. [PMID: 24113399 PMCID: PMC3856897 DOI: 10.1016/j.mimet.2013.09.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Revised: 09/25/2013] [Accepted: 09/30/2013] [Indexed: 01/15/2023]
Abstract
The lack of a versatile system to control gene expression in Helicobacter pylori has hampered efforts to study H. pylori physiology and pathogenesis. To overcome these limitations, we evaluated the utility of an inducible system based on the well-characterized Tet repressor (TetR) and Tet operator (tetO). As validation of this system, we introduced three copies of tetO into the promoter region upstream of the cagUT operon (encoding two virulence factors required for function of the H. pylori Cag type IV secretion system) and expressed tetR by introducing a codon-optimized gene into the chromosomal ureA locus. Introduction of the tetO copies upstream of cagUT did not disrupt promoter activity, as determined by immunoblotting for CagT. The subsequent introduction of tetR, however, did repress CagT synthesis. Production of CagT was restored when strains were cultured in the presence of the inducer, anhydrotetracycline. To demonstrate one potential application of this new tool, we analyzed the function of the Cag type IV secretion system. When the modified H. pylori strains were co-cultured with AGS cells, activity of the Cag type IV secretion system was dependent on the presence of anhydrotetracycline as evidenced by inducer-dependent induction of IL-8 secretion, CagA translocation, and appearance of type IV secretion system pili at the bacteria-host interface. These studies demonstrate the effectiveness of the tetR-tetO system to control gene expression in H. pylori and provide an improved system for studying H. pylori physiology and pathogenesis.
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Affiliation(s)
- Mark S. McClain
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Stacy S. Duncan
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Jennifer A. Gaddy
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee, United States of America
| | - Timothy L. Cover
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee, United States of America
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42
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Abstract
Gastric adenocarcinoma is a leading cause of cancer-related death worldwide, and Helicobacter pylori infection is one of the strongest known risk factors for this malignancy. H. pylori strains exhibit a high level of genetic diversity, and the risk of gastric cancer is higher in persons carrying certain strain types (for example, those that contain a cag pathogenicity island or type s1 vacA alleles) than in persons carrying other strain types. Additional risk factors for gastric cancer include specific human genetic polymorphisms and specific dietary preferences (for example, a high-salt diet or a diet deficient in fruits and vegetables). Finally, iron-deficiency anemia is a risk factor for gastric cancer. Recent studies have provided evidence that several dietary risk factors for gastric cancer directly impact H. pylori virulence. In this review article, we discuss mechanisms by which diet can modulate H. pylori virulence and thereby influence gastric cancer risk.
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Affiliation(s)
- Timothy L Cover
- Division of Infectious Diseases; Vanderbilt University School of Medicine; Nashville, TN USA,Department of Pathology, Microbiology, and Immunology; Vanderbilt University School of Medicine; Nashville, TN USA,Veterans Affairs Tennessee Valley Healthcare System; Nashville, TN USA
| | - Richard M Peek, Jr
- Division of Gastroenterology, Department of Medicine; Vanderbilt University School of Medicine; Nashville, TN USA,Correspondence to: Richard M Peek, Jr,
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