Skip to Main content Skip to Navigation
Theses

Identification des facteurs de pathogénicité de la bactérie Vibrio tapetis, responsable de la maladie de l'anneau brun chez la palourde japonaise Ruditapes philippinarum et de mortalités chez les poissons marins

Abstract : The main objective of this thesis is to study the mechanisms related to the pathogenicity of V. tapetis. For this purpose, we developed 2 research axes. The first one aimed at studying the virulence of V. tapetis by answering the following 2 issues: What are the genes involved in the virulence of V. tapetis? and Are there host-specific markers of the virulence of V. tapetis? The second research axis concerned pathogen-host interactions and addressed the following 2 issues: What are the genes expressed during infection in the host? and What are the modulations in the animal associated with pH and temperature during infection? The main findings of this thesis are: (i) V. tapetis, in the context of BRD, induces a down expression of genes involved in the immune response anda deregulation of genes involved in the stabilization and synthesis of actin filaments (ii) This pathogen also induces a decrease in lysosomal activity on exposed hemocytes (iii) The effect of V. tapetis on the actin cytoskeleton and on the decrease in lysosomal activity is independent of the type IV secretion system (T4SS) (iv) The type IV secretion system (T4SS) is involved in the development of BRD but is not essential to induce this disease (v) In the context of BRD and of the loss of hemocyte adhesions properties in vitro, V. tapetis is able to modulate the pH of extrapallial fluids, respectively in the first days and hours of infection (vi) Finally, the "strains typing" approach based on MALDITOF makes it possible to discriminate between V. tapetis strains according to their pathogenicity with regard to Manila clam.
Document type :
Theses
Complete list of metadata

Cited literature [348 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-02969604
Contributor : Abes Star :  Contact
Submitted on : Friday, October 16, 2020 - 5:00:08 PM
Last modification on : Wednesday, November 3, 2021 - 5:29:24 AM
Long-term archiving on: : Sunday, January 17, 2021 - 11:29:05 PM

File

These-2019-SML-Microbiologie-R...
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-02969604, version 1

Collections

Citation

Alexandra Rahmani. Identification des facteurs de pathogénicité de la bactérie Vibrio tapetis, responsable de la maladie de l'anneau brun chez la palourde japonaise Ruditapes philippinarum et de mortalités chez les poissons marins. Microbiologie et Parasitologie. Université de Bretagne occidentale - Brest, 2019. Français. ⟨NNT : 2019BRES0059⟩. ⟨tel-02969604⟩

Share

Metrics

Record views

202

Files downloads

206