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La Réponse Au NO Au Centre De La Pathogenèse Bactérienne Et Cible D’Antibiotiques Innovants Constance Porrini

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La Réponse Au NO Au Centre De La Pathogenèse Bactérienne Et Cible D’Antibiotiques Innovants Constance Porrini La réponse au NO au centre de la pathogenèse bactérienne et cible d’antibiotiques innovants Constance Porrini To cite this version: Constance Porrini. La réponse au NO au centre de la pathogenèse bactérienne et cible d’antibiotiques innovants. Médecine humaine et pathologie. Université Paris-Saclay, 2020. Français. NNT : 2020UP- ASA008. tel-03175216 HAL Id: tel-03175216 https://pastel.archives-ouvertes.fr/tel-03175216 Submitted on 19 Mar 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. La réponse au NO au centre de la pathogenèse bactérienne et cible d’antibiotiques innovants Thèse de doctorat de l'université Paris-Saclay École doctorale n°581, Agriculture, Alimentation, Biologie, Environnement, Santé - ABIES Spécialité de doctorat : Microbiologie INRAE, AgroParisTech, Micalis Institute, 78350, Jouy-en-Josas, France Référent : AgroParisTech Thèse présentée et soutenue à Paris-Saclay, le 12 juin 2020, par Constance PORRINI Composition du Jury Stéphanie BURY-MONE Présidente Professeure, Université Paris-Saclay Véronique BROUSSOLLE Rapporteur et Examinatrice Directrice de Recherche, INRAE Centre Provence-Alpes-Côte d'Azur Olivier DUSSURGET Rapporteur et Examinateur Professeur, Université Paris-Diderot Priscilla BRANCHU Examinatrice Chargée de Recherche, INRAE Centre Occitanie-Toulouse 8 Nalini RAMA RAO Directrice de thèse Directrice de Recherche, INRAE Centre IdF-Jouy-en-Josas-Antony : 2020UPASA00 : NNT Thèse deThèse doctorat 2 REMERCIEMENTS J’ai réalisé ce travail à l’Institut Micalis de l’INRAE de Jouy-en-Josas, financé par l’IDI Paris Saclay (Initiative Doctorale Interdisciplinaire), sous la direction du Dr Nalini Rama Rao. Je la remercie de m’avoir accueillie dans l’équipe pendant ces trois années. Je remercie également chaque membre de l’équipe PIMs passé et présent pour leur accueil chaleureux et leur joie de vivre. Plus particulièrement, je remercie Lucie Lebreuilly et Fairouz Gzara pour leur aide au laboratoire et sur le manuscrit. Jasmina Vidic pour son énergie et son inspiration, et Rozenn Dervyn pour tout ce qu’elle m’a enseigné, toutes nos discussions, tous ses conseils et son grand cœur. Je remercie également Cyprien Guérin et Pierre Nicolas de l’unité Maiage pour leur immense aide en bio-informatique et en statistique. Je remercie également Stéphane Aymerich, Directeur de l’Institut Micalis, ainsi que mes collègues qui étaient à mes côtés, plus particulièrement Élise Borezée-Durant, Damien Lipuma, Vincent Saillant, les copains du volley et du « Repas DéJeunes » et les ITs qui partageaient bien plus qu’un couloir : Franck Gérard, Emmanuel Cuervo et Momar Mbow. Je remercie également l’école Doctorale ABIES, son directeur et directeur adjoint Alexandre Pery et Pierre Larraufie et mon comité de thèse, les Dr Shaynoor Dramsi et Marion Leclerc. Je remercie tous mes amis et ma famille qui sont une source d’inspiration et sur qui je peux toujours compter, et plus particulièrement Méliné Négroni, François Berthelot, Alison Dominguez et Océane Bataille pour leur aide dans la rédaction. Je remercie mon père Jean Porrini pour toute son aide et ses conseils depuis toujours. Enfin, je remercie Emeric Gaffiero pour son soutien inconditionnel pendant toutes ces années. 3 A mon fils Léo 4 La réponse au NO au centre de la pathogenèse bactérienne et cible d’antibiotiques innovants RÉSUMÉ Le NO ou monoxyde d’azote est un radical libre très réactif omniprésent dans le monde du vivant. Il est capable de modifier les bases d’ADN, les lipides membranaires, l’activité des enzymes… Il a de nombreux rôles biologiques chez les animaux, les plantes, les champignons et les bactéries. Il est notamment produit par les cellules de l’immunité innée pour lutter contre les infections. Pour infecter l’hôte, certaines bactéries pathogènes ont mis au point des mécanismes de résistance à ce stress. Bacillus cereus, est une bactérie pathogène qui est capable de résister au NO. Cependant ces mécanismes ne sont pas tout à fait élucidés. La protéine Mfd est connue comme pouvant réparer les lésions du NO sur l’ADN et augmenter la résistance au stress NO. D’une part, une approche transcriptomique sur Bacillus cereus a permis de mettre en évidence, une région du génome particulièrement activée en présence de NO. Cette région contient des gènes qui codent pour une protéine de réparation des dommages causés par le NO, une enzyme de métabolisme de l’azote et des enzymes de biosynthèse du sirohème, un groupement ferreux. D’autre part, un inhibiteur de la protéine Mfd a été testé pour son efficacité antibactérienne sur Bacillus cereus et sur quatre bactéries responsables d’infections en impasse thérapeutique à cause de l’apparition de résistances aux antibiotiques. MOTS-CLÉS Monoxyde d'azote, pathogène, Bacillus cereus, antibiotique, réponse immunitaire. 5 Table des matières Introduction ................................................................................................................................. 10 I. Le monoxyde d’azote ........................................................................................................... 11 A. Le NO chez les mammifères.................................................................................................................13 B. Propriétés biologiques du NO et des RNS ............................................................................................21 C. Le NO dans le monde procaryote .........................................................................................................28 II. Bactérie modèle : Bacillus cereus ........................................................................................ 43 A. Le groupe Bacillus cereus ....................................................................................................................43 B. Toxines et facteurs de virulence ...........................................................................................................44 C. La pathogénicité du groupe B. cereus ...................................................................................................50 III. Les antibiotiques .............................................................................................................. 53 A. Histoire : Découvertes et mises au point...............................................................................................53 B. Classes et cibles des antibiotiques actuels ............................................................................................55 C. La résistance aux antibiotiques .............................................................................................................58 D. Quels espoirs ? Quelles options ............................................................................................................65 E. Les bactéries ESKAPE .........................................................................................................................70 Chapitre 1 : Caractérisation d’une région clé impliquée dans la réponse au stress NO de Bacillus cereus .............................................................................................................................. 74 I. Introduction ......................................................................................................................... 77 II. Material and method ........................................................................................................... 79 III. Results .............................................................................................................................. 82 A. Resistance of B. cereus to NO stress ....................................................................................................82 B. A 6 genes region over activated by nitric oxide in the early response ..................................................85 C. Organization and regulation of the region of interest ...........................................................................86 D. Specificity to NO stress ........................................................................................................................89 IV. Discussion ........................................................................................................................ 90 Chapitre 2 : La réponse au NO cible d’un antibiotique innovant - Un inhibiteur dirigé contre Mfd-................................................................................................................................... 94 I. Introduction ......................................................................................................................... 94 II. Matériels et méthodes.......................................................................................................... 95 III. Résultats........................................................................................................................... 95 A. ..............................................................................................................................................................95
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