Project description:Vibrio alginolyticus is a Gram-negative marine bacterium. A limited population of the organisms causes acute gastroenteritis in humans. In this study, Vibrio alginolyticus wild type strain EPGS is compared with the mutants of Ser-Thr kinase PpkA and phosphatase PppA, after cultured for 7h, in Luria-Bertani containing medium 3 % NaCl at 30 C. Our goal is to determine the ppkA and pppA regulon.
Project description:Vibrio alginolyticus is a Gram-negative marine bacterium. A limited population of the organisms causes acute gastroenteritis in humans. In this study, Vibrio alginolyticus wild type strain EPGS is compared with the mutants of Ser-Thr kinase PpkA and phosphatase PppA, after cultured for 7h, in Luria-Bertani containing medium 3 % NaCl at 30 C. Our goal is to determine the ppkA and pppA regulon. Three wild type and five mutant Vibrio alginolyticus samples were compared.
Project description:In recent years, due to the influence of climate change and rising sea temperature, the incidence of Vibrio alginolyticus infections is increasing, and becoming the second most common Vibrio species reported in human illness. Therefore, better understanding of the pathogenic mechanism of V. alginolyticus infection is urgently needed. Vvrr1 (Vibrio virulence regulatory RNA 1) is a new found ncRNA predicted to be closely related to the adhesion ability of V. alginolyticus through the previous RNA-seq. In this study, the target genes of Vvrr1 were fully screened and verified by constructing Vvrr1 over-expressed strains and proteome sequencing technology.
Project description:RNA-seq analysis demonstrated that VqsA (18672) controls ~275 genes' expression in V. alginolyticus. Collectively, our data established that VqsA plays essential roles in QS regulation and may facilitate the illumination of the mechanisms bacterial cells sense environmental signals and integrate them into coordinated QS responses.
Project description:Vibrio species distribute ubiquitously in marine and coastal environments, with implications for severe infectious diseases in human and marine animals. However, precisely what defensive strategies the host employ against Vibrio pathogens with distinct virulence remain poorly understood. Being an ecologically relevant host, the oyster Crassostrea hongkongensis serves as an excellent model for elucidating mechanisms underlying host-Vibrio interactions. In this study, we generated one mutant Vibrio alginolyticus strains (V. alginolyticus△VSCC) with attenuated virulence by knocking out the VSCC encoding gene, one of the core components of type III secretion systems (T3SSs), based on the evidence that V. alginolyticus△VSCC infection leads to a marked reduction in the apoptotic rate of hemocyte hosts, compared to V. alginolyticusWT control. In comparative proteomics, it was revealed that distinct immune responses were elicited upon encounter with V. alginolyticus strains of different virulence. Quite strikingly, the peroxisomal and apoptotic pathways are activated by V. alginolyticusWT infection, whereas phagocytosis and cell adhesion were enhanced in V. alginolyticus△VSCC infection. Collectively, we conclude that adaptation in host immune responses is determined in part by pathogen virulence, which safeguards elimination of invading bacteria in efficient and timely manners.
