Selection of Vibrio crassostreae relies on a plasmid expressing a type 6 secretion system cytotoxic for host immune cells - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Environmental Microbiology Année : 2019

Selection of Vibrio crassostreae relies on a plasmid expressing a type 6 secretion system cytotoxic for host immune cells

Résumé

Pacific oyster mortality syndrome affects juveniles of Crassostrea gigas oysters and threatens the sustainability of commercial and natural stocks of this species. Vibrio crassostreae (V. crassostreae) has been repeatedly isolated from diseased animals, and the majority of the strains have been demonstrated to be virulent for oysters. In this study, we showed that oyster farms exhibited a high prevalence of a virulence plasmid carried by V. crassostreae, while oysters, at an adult stage, were reservoirs of this virulent population. The pathogenicity of V. crassostreae depends on a novel transcriptional regulator, which activates the bidirectional promoter of a type 6 secretion system (T6SS) genes cluster. Both the T6SS and a second chromosomal virulence factor, r5.7, are necessary for virulence but act independently to cause haemocyte (oyster immune cell) cytotoxicity. A phylogenetically closely related T6SS was identified in V. aestuarianus and V. tapetis, which infect adult oysters and clams respectively. We propose that haemocyte cytotoxicity is a lethality trait shared by a broad range of mollusc pathogens, and we speculate that T6SS was involved in parallel evolution of pathogen for molluscs.
Fichier principal
Vignette du fichier
Piel et al. - Selection of Vibrio crassostreae relies on a plasm.pdf (1.19 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)
Loading...

Dates et versions

hal-02298754 , version 1 (27-09-2019)

Identifiants

Citer

Damien Piel, Maxime Bruto, Adèle James, Yannick Labreuche, Christophe Lambert, et al.. Selection of Vibrio crassostreae relies on a plasmid expressing a type 6 secretion system cytotoxic for host immune cells. Environmental Microbiology, 2019, ⟨10.1111/1462-2920.14776⟩. ⟨hal-02298754⟩
68 Consultations
191 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More