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1. Helicobacter pylori Adapts to Chronic Infection and Gastric Disease via pH-Responsive BabA-Mediated Adherence

Author

Verena Königer, D. Scott Merrell, Roman Andriiovych Moskalenko, Rainer Haas, Thomas Borén, Sara Henriksson, Jafar Mahdavi, Abhijit Chowdhury, Johan Ögren, Anders Hofer, Jay V. Solnick, Dan Danielsson, Sara K. Lindén, Dag Ilver, Konstantinos S. Papadakos, Susanne Vikström, Jörgen Ådén, Jan Holgersson, Gerhard Gröbner, Alexej Schmidt, Jeanna Bugaytsova, Oscar Björnham, Göran O. Bylund, Rolf Sjöström, Stefan Oscarson, Dionyssios N. Sgouras, Lori M. Hansen, Yevgen A Chernov, Anders Esberg, Kristof Moonens, Christopher Aisenbrey, Charles Kelly, Ludmilla A. Morozova-Roche, Jeannette M. Whitmire, Beatriz Martinez-Gonzalez, Asish K. Mukhopadhyay, Angela Eldridge, Nicklas Strömberg, Robert H. Gilman, Andre Dubois, Lars Engstrand, Staffan Schedin, Brett A. Chromy, Justine Younson, Matthew Goldman, Anna Shevtsova, Macarena P. Quintana-Hayashi, Hui Liu, Magnus Unemo, Lena Rakhimova, Anna Åberg, Sebastian Suerbaum, Anna Arnqvist, Pär Gideonsson, Maréne Landström, Douglas E. Berg, Kristoffer Brännström, Anders Olofsson, Melissa Mendez, G. Balakrish Nair, Han Remaut, Umeå University, School of Life Sciences, University of Nottingham, UK (UON), Sahlgrenska Academy at University of Gothenburg [Göteborg], Université libre de Bruxelles (ULB), VIB-VUB Center for Structural Biology [Bruxelles], VIB [Belgium], Sumy State University, Max Von Pettenkofer Institute (MVP), Ludwig-Maximilians-Universität München (LMU), Uniformed Services University of the Health Sciences (USUHS), King‘s College London, Johns Hopkins Bloomberg School of Public Health [Baltimore], Johns Hopkins University (JHU), School of Digestive and Liver Diseases [Kolkata] (SDLD), National Institute of Cholera and Enteric Diseases, Translational Health Science and Technology Institute [Faridabad] (THSTI), Institut Pasteur Hellénique, Réseau International des Instituts Pasteur (RIIP), Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Karolinska Institutet [Stockholm], Örebro University Hospital [Örebro, Sweden], Hannover Medical School [Hannover] (MHH), German Center for Infection Research - partner site Hannover-Braunschweig (DZIF), School of Chemistry and Chemical Biology (UCD), University College Dublin [Dublin] (UCD), University of California [Davis] (UC Davis), University of California, German Center for Infection Research, Partnersite Munich (DZIF), Département d'Informatique [Bruxelles] (ULB), Faculté des Sciences [Bruxelles] (ULB), Université libre de Bruxelles (ULB)-Université libre de Bruxelles (ULB), University of California [San Diego] (UC San Diego), This work was supported by grants from Vetenskapsrådet (VR/M) to T.B. and S.K.L., Cancerfonden to T.B. and A.A., VR/NT to A.A. and S. Schedin, Formas to S.K.L., the J.C. Kempe and Seth M. Kempe Memorial Foundation, the Knut and Alice Wallenberg Foundation (2012.0090) to T.B. and M.L., European Union Seventh Framework Program GastricGlycoExplorer ITN grant number 316929 to T.B. and Y.A.C., Magn. Bergvall’s Foundation to S. Schedin, DFG (SFB 900/A1) to S. Suerbaum, DFG (HA2697/16-1) to R.H., FP6 ANR-06-PATHO-00701 ERA-NET and Actions Concertées Inter-Pasteuriennes (ACIP) (2006) to D.N.S., NIH R01DK063041 to D.E.B., NIH CA082312 to D.S.M., NIH AI070803 and AI081037 to J.V.S., CSIR project, India (No. 37(1640)/14/EMR –II) to A.K.M., and VIB and FWO (grants: G033717N and 12H8416N) to K.M. and H.R., This paper is dedicated to the memory of our friend, collaborator, and co-author Dr. Andre Dubois, a great scientist who contributed importantly both intellectually and materially to this project. We thank S. Michopoulos and G. Mantzaris for H. pylori clinical isolates and Ö. Furberg (NoPolo.se), N. Ulander (softplanbangkok.com), S. Lindström, and M. Borén for the digital movie, tech, art, and figure work, respectively., Vrije Universiteit Brussel, Basic (bio-) Medical Sciences, Structural Biology Brussels, and Department of Bio-engineering Sciences

Subjects
0301 basic medicine, MESH: Hydrogen-Ion Concentration, Gastric acidity, MESH: Helicobacter Infections/pathology, MESH: Helicobacter pylori/physiology, Disease, adaptation, Bacterial Adhesion, polymorphism, acid responsiveness, MESH: Bacterial Adhesion, Bacterial, Hydrogen-Ion Concentration, gastric acidity, Adhesins, 3. Good health, Cell and molecular biology, medicine.anatomical_structure, Infectious Diseases, MESH: Gastric Mucosa/microbiology, Medical Microbiology, 030106 microbiology, Immunology, Digestive Diseases - (Peptic Ulcer), Biology, blood group antigen-binding adhesion, Microbiology, Helicobacter Infections, diversity, Vaccine Related, 03 medical and health sciences, Virology, ABO blood group system, Biodefense, Gastric mucosa, medicine, MESH: Helicobacter Infections/microbiology, multimerization, Adhesins, Bacterial, subpopulations, Helicobacter pylori, Prevention, gastric cancer, MESH: Adhesins, Bacterial/metabolism, biology.organism_classification, [SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology, MESH: Gastric Mucosa/pathology, Bacterial adhesin, Chronic infection, 030104 developmental biology, Emerging Infectious Diseases, Gastric Mucosa, Parasitology, Digestive Diseases
Abstract

The BabA adhesin mediates high-affinity binding of Helicobacter pylori to the ABO blood group antigen-glycosylated gastric mucosa. Here we show that BabA is acid responsive-binding is reduced at low pH and restored by acid neutralization. Acid responsiveness differs among strains; often correlates with different intragastric regions and evolves during chronic infection and disease progression; and depends on pH sensor sequences in BabA and on pH reversible formation of high-affinity binding BabA multimers. We propose that BabA's extraordinary reversible acid responsiveness enables tight mucosal bacterial adherence while also allowing an effective escape from epithelial cells and mucus that are shed into the acidic bactericidal lumen andthat bio-selection and changes in BabA bindingproperties through mutation and recombination with babA-related genes are selected by differencesamong individuals and by changes in gastric acidity over time. These processes generate diverse H.pylori subpopulations, in which BabA's adaptive evolution contributes to H.pylori persistence and overt gastric disease.

Published
2017

2. Actin activates Pseudomonas aeruginosa ExoY nucleotidyl cyclase toxin and ExoY-like effector domains from MARTX toxins

Author

Undine Mechold, Abdelkader Namane, Cosmin Saveanu, Vasily Ogryzko, Alexander Belyy, Daniel Ladant, Lina Worpenberg, Souad Fellous, Dorothée Raoux-Barbot, Christien Merrifield, Elodie Assayag, Violaine David, Louis Renault, Véronique Henriot, Biochimie des Interactions Macromoléculaires / Biochemistry of Macromolecular Interactions, Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS), Gamaleya Research Center, Génétique des Interactions Macromoléculaires, Signalisation, noyaux et innovations en cancérologie (UMR8126), Université Paris-Sud - Paris 11 (UP11)-Institut Gustave Roussy (IGR)-Centre National de la Recherche Scientifique (CNRS), Institut de Biologie Intégrative de la Cellule (I2BC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), This project was funded by the Institut Pasteur under #PTR425 to U.M. and C.S. and by CNRS. A.B. was supported by a stipend from the Pasteur—Paris University (PPU) International PhD Program. We acknowledge the core facilities of Imagerie-Gif,(http://www.i2bc.paris-saclay.fr), supported by ‘France-BioImaging’ (ANR-10-INBS-04-01). This paper is dedicated to the memory of Vasily Ogryzko (1960–2016)., ANR-10-INBS-0004,France-BioImaging,Développment d'une infrastructure française distribuée coordonnée(2010), Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS), Biochimie des Interactions Macromoléculaires, Institut Pasteur [Paris]-Centre National de la Recherche Scientifique ( CNRS ), Signalisation, noyaux et innovations en cancérologie ( UMR8126 ), Université Paris-Sud - Paris 11 ( UP11 ) -Institut Gustave Roussy ( IGR ) -Centre National de la Recherche Scientifique ( CNRS ), Institut de Biologie Intégrative de la Cellule ( I2BC ), Université Paris-Sud - Paris 11 ( UP11 ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay-Centre National de la Recherche Scientifique ( CNRS ), and ANR-10-INBS-04-01/10-INBS-0004,France-BioImaging,Développment d'une infrastructure française distribuée coordonnée ( 2010 )

Subjects
0301 basic medicine, Science, Bacterial Toxins, General Physics and Astronomy, macromolecular substances, Saccharomyces cerevisiae, [SDV.BC]Life Sciences [q-bio]/Cellular Biology, [ SDV.MP.BAC ] Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology, Filamentous actin, Cyclase, Article, General Biochemistry, Genetics and Molecular Biology, Type three secretion system, Adenylyl cyclase, 03 medical and health sciences, Cyclic nucleotide, chemistry.chemical_compound, Bacterial Proteins, ExoY, Type III Secretion Systems, Adenylate cyclase, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, [ SDV.BBM ] Life Sciences [q-bio]/Biochemistry, Molecular Biology, Actin, Multidisciplinary, Virulence, Mass spectrometry, [ SDV.BC ] Life Sciences [q-bio]/Cellular Biology, Chemistry, Effector, General Chemistry, Transfection, Guanylate cyclase, [SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology, Actins, 3. Good health, Cell biology, 030104 developmental biology, Glucosyltransferases, Mutation, Pseudomonas aeruginosa, Protein Binding
Abstract

The nucleotidyl cyclase toxin ExoY is one of the virulence factors injected by the Pseudomonas aeruginosa type III secretion system into host cells. Inside cells, it is activated by an unknown eukaryotic cofactor to synthesize various cyclic nucleotide monophosphates. ExoY-like adenylate cyclases are also found in Multifunctional-Autoprocessing Repeats-in-ToXin (MARTX) toxins produced by various Gram-negative pathogens. Here we demonstrate that filamentous actin (F-actin) is the hitherto unknown cofactor of ExoY. Association with F-actin stimulates ExoY activity more than 10,000 fold in vitro and results in stabilization of actin filaments. ExoY is recruited to actin filaments in transfected cells and alters F-actin turnover. Actin also activates an ExoY-like adenylate cyclase MARTX effector domain from Vibrio nigripulchritudo. Finally, using a yeast genetic screen, we identify actin mutants that no longer activate ExoY. Our results thus reveal a new sub-group within the class II adenylyl cyclase family, namely actin-activated nucleotidyl cyclase (AA-NC) toxins., The ExoY toxin is injected by Pseudomonas aeruginosa into host cells, where it is activated by an unknown host factor. Here the authors identify such factor as filamentous actin.

Published
2016

3. Synchrotron FTIR microspectroscopy of Escherichia coli at single-cell scale under silver-induced stress conditions

Author

Claire Saulou, Muriel Mercier-Bonin, Isabelle Fourquaux, Paul Dumas, Claude Maranges, Frédéric Jamme, Muriel Cocaign-Bousquet, Laurence Girbal, Génie et Microbiologie des Procédés Alimentaires (GMPA), Institut National de la Recherche Agronomique (INRA)-AgroParisTech, Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés (LISBP), Institut National de la Recherche Agronomique (INRA)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT), Unité de recherche sur les Biopolymères, Interactions Assemblages (BIA), Institut National de la Recherche Agronomique (INRA), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT), Centre de Microscopie Électronique Appliquée à la Biologie (CMEAB), Toulouse Réseau Imagerie-Genotoul ( TRI-Genotoul), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), The authors gratefully acknowledge the 'BioPleasure' project of the Research National Agency (ANR-07-BLAN-0196-01) for funding., The research described in this paper was performed at the French national synchrotron facility SOLEIL (Gif-sur- Yvette, France), using the SMIS beamline (proposal no 20090556)., ANR-07-BLAN-0196,BIOPLEASURE,Plasma - surface engineering for biofilm prevention(2007), AgroParisTech-Institut National de la Recherche Agronomique (INRA), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées, Institut National des Sciences Appliquées (INSA), Hôpital de Rangueil, CHU Toulouse [Toulouse]-CHU Toulouse [Toulouse]-Toulouse Réseau Imagerie-Genotoul ( TRI-Genotoul), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National de la Recherche Agronomique (INRA), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Hôpital de Rangueil, and CHU Toulouse [Toulouse]-CHU Toulouse [Toulouse]

Subjects
In situ, Analytical chemistry, medicine.disease_cause, Biochemistry, Analytical Chemistry, 03 medical and health sciences, Stress, Physiological, Spectroscopy, Fourier Transform Infrared, medicine, Escherichia coli, Fourier transform infrared spectroscopy, [SDV.BBM.BC]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biochemistry [q-bio.BM], Protein secondary structure, 030304 developmental biology, 0303 health sciences, biology, Ionic silver, 030306 microbiology, Chemistry, Synchrotron FTIR-ATR microspectroscopy, Single-cell scale, [CHIM.MATE]Chemical Sciences/Material chemistry, biology.organism_classification, [SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology, [SDV.BBM.BC]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biomolecules [q-bio.BM], Antibacterial effect, Transmission electron microscopy, Attenuated total reflection, Ultrastructure, Biophysics, Silver Nitrate, Single-Cell Analysis, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, Synchrotrons, Bacteria
Abstract

International audience; The present work was focused on elucidating biochemical changes in the model bacterium Escherichia coli exposed to ionic silver mediated stress, at a single-cell scale. In order to achieve this, in situ synchrotron Fourier-transform infrared (sFTIR) microspectroscopy was performed, for the first time, on individual cells by attenuated total reflectance (ATR) combined with the use of zinc-selenide hemisphere for high spatial resolution. In a first part, the potential of the method was evaluated on bacteria subjected to a lethal 100 μM AgNO3 concentration for 2 h compared to untreated 100 % viable cells. Differences in cell composition were assessed for the C–H stretching and protein spectral regions, indicating that the inhibitory action was targeted against both fatty acids and proteins. Transmission electron microscopy (TEM) confirmed morphological damages of the cell ultrastructure. The relevance of ATR-sFTIR microspectroscopy for highlighting the heterogeneity in Ag+-mediated effects within a given bacterial population was also pointed out. In a second part, cells were exposed to sub-lethal Ag+ concentrations (

Published
2013

4. Characterization of Staphylococcus aureus strains associated with food poisoning outbreaks in France

Author

Jacques-Antoine Hennekinne, Annaëlle Kerouanton, L. Petit, C. Letertre, Anne Brisabois, O. Chesneau, M.L. De Buyser, Agence Française de Sécurité Sanitaire des Aliments (AFSSA), Agents antibactériens, Institut Pasteur [Paris], We acknowledge the technical assistance of Trinh Tam Dao, Marie-Odile Delbart, Muriel Marault, and Anne Morvan. We dedicate this paper to the memory of Névine El Solh who contributed to the phage-typing and who passed away in January 2005., and Institut Pasteur [Paris] (IP)

Subjects
Salmonella, Enterotoxin, MESH: Base Sequence, medicine.disease_cause, SmaI, Disease Outbreaks, MESH: Genotype, Enterotoxins, Genotype, MESH: Staphylococcus aureus, MESH: Enterotoxins, Cluster Analysis, MESH: Disease Outbreaks, MESH: Phylogeny, Phylogeny, 2. Zero hunger, 0303 health sciences, General Medicine, PFGE, 3. Good health, Electrophoresis, Gel, Pulsed-Field, Phenotype, MESH: Electrophoresis, Gel, Pulsed-Field, Staphylococcus aureus, MESH: Staphylococcal Food Poisoning, France, Staphylococcal Food Poisoning, Food Contamination, Biology, MESH: Phenotype, Microbiology, Food-poisoning, 03 medical and health sciences, medicine, Pulsed-field gel electrophoresis, Humans, MESH: Food Microbiology, 030304 developmental biology, MESH: Humans, Base Sequence, 030306 microbiology, Outbreak, MESH: Food Contamination, MESH: Cluster Analysis, [SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology, MESH: France, Food Microbiology, Food Science
Abstract

International audience; Enterotoxins produced by Staphylococcus aureus are responsible for staphylococcal food-poisoning outbreaks (SFPO). In France, SFPO are the second cause of food-borne diseases after Salmonella. However, very little is known about the strains involved. The objective of this study was to characterize the staphylococcal strains related to these SFPO through phenotypic and genotypic analyses. A total of 178 coagulase-positive staphylococcal isolates recovered from 31 SFPO (1981-2002) were screened through biotyping. Thirty-three strains representative of the different biotypes in each SFPO were further examined for SmaI macrorestriction-type, phage-type, resistance to various antimicrobial drugs, presence of staphylococcal enterotoxin (se) genes sea to sei, and production of enterotoxins SEA to SED. All these 33 strains were identified as S. aureus species: 27 were of human biotypes and six ovine or non-host-specific biotypes. Most (74.1%) strains reacted with group III phages. Eleven strains were resistant to at least two classes of antibiotics and among them, two were resistant to methicillin. Twenty-nine strains carried one or several of the eight se genes tested; the gene sea was most common (n=23), and often linked to sed (n=12) or seh (n=5). The novel se genes seg-i were in all cases associated with se genes sea to sed except for one strain which carried only seg and sei. Pulsed-Field Gel Electrophoresis (PFGE) of SmaI macrorestriction digests of the 33 strains discriminated 32 PFGE patterns grouped into nine biotype-specific clusters. All five strains carrying sea and seh were grouped together into the same sub-cluster. Three of the four se-gene-negative strains were in one PFGE cluster: all four should be tested for se genes not included in this study and, if negative, be further investigated for the presence of unidentified SEs.

Published
2007