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: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: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.
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:The heterogeneity of bacterial cells in biofilms is an important property. We performed single-cell sequencing to profile heterogeneous cell populations within Vibrio alginolyticus biofilm. Our analysis has revealed the key functional compartments for the composition and development of biofilms
Project description:The Manila clam (Ruditapes philippinarum) is a cultured bivalve species with high worldwide commercial importance. Nevertheless, diseases can cause high economical losses. For this reason, the study of immune genes in bivalve mollusks has increased in the last years. The present work describes the construction of the first R. philippinarum microarray containing immune-related hemocyte sequences and its application for the study of the gene transcription profiles of hemocytes from clams challenged with Vibrio alginolyticus through a time course. A comparative analysis of gene expression was conducted between R. philippinarum infected and non-infected by V. alginolyticus clam hemocytes. Clams (n=100) were notched in the shell next to the adductor muscles and injected with 100 µl of Vibrio alginolyticus, strain TA15, (10^8 UFC/ml in PBS) to mimic an intramuscular infection. Controls (n=100) were injected with 100 µl of PBS. After stimulation, clams were returned to the tanks and maintained at 15ºC until sampling at 3, 8, 24, and 72 hours after challenge Hemolymph (1 ml) was withdrawn from the adductor muscle of the clams with a 0.5mm diameter (25G) disposable needle. Hemolymph from four individuals was pooled and biological replicates were taken at each sampling point. Hemolymph was centrifuged at 4°C at 3000 g for 10 minutes. The pellet was resuspended in 250 µl of Trizol (Invitrogen). Total RNA isolation was conducted following the manufacturer's specifications in combination with the RNeasy mini kit (Qiagen) for RNA purification after DNase I treatment. Gene expression profiling was performed using an R. philippinarum oligo-DNA microarray of 13,671 probes based on single-colour detection (Cyanine-3 only). Microarrays were scanned with Agilent scanner G2565BA at a resolution of 5 microns; all slides were scanned twice at two different sensitivity settings (XDRHi 100% and XDRLo 10%); the scanner software created a unique ID for each pair of XDR scans and saved it to both scan image files. Feature Extraction (FE) 9.5 used XDR ID to link the pairs of scans together automatically when extracting data. The signal left after all the FE processing steps have been completed is ProcessedSignal that contains the Multiplicatively Detrended, Background-Subtracted Signal.
Project description:We report ChIP-seq for C/EBPb and ATF4 in human mesenchymal stem cells and in a cell-free system using naked genomic DNA. ChIP-Seq for GR, RNA Polymerase II, and H3K27 acetylation in hMSCs cultured under different adipogenic conditions are also presented. hMSCs cultured at high or low cell seeding densities in the presence or absence of adipogenic induction cocktail