Project description:Objectives: determination of transcription start sites in Vibrio harveyi genome and discovery of new transcripts Methods: we performed differential seqencing of total RNA isolated from o.n. control Vibrio harveyi cultures. Sample treatment with Terminator EXonuclease (TEX) allowed differenciation of primary and secondary transcripts, helping in the definition of transcription start sites (TSS) Results: by data-mining RNA-seq data and performing some Northern Blot experiments we were able to detect new putative small-RNAs, along with these results, a more deep analisys of our RNA-seq data will give futher insight into genetic organization of Vibrio harveyi genome to help in its investigation
Project description:In this research, we used RNA-sequencing technology to detect genome-wide differentially expressed genes in spleen and gill of Vibrio harveyi -infected Takifugu rubripes.This high-throughput sequencing could help us to understand new mechanisms of action of V. harveyi induced aquaculture fish disease.
Project description:In marine Vibrio species, chitin-induced natural transformation enables bacteria to take up DNA from the external environment and integrate it into their genome via homologous recombination. Expression of the master competence regulator TfoX bypasses the need for chitin induction and drives expression of the genes required for competence in several Vibrio species. Here, we show that TfoX expression in two Vibrio campbellii strains, DS40M4 and NBRC 15631, enables high frequencies of natural transformation. Conversely, transformation was not achieved in the model quorum-sensing strain V. campbellii BB120 (previously classified as Vibrio harveyi). Surprisingly, we find that quorum sensing is not required for transformation in V. campbellii DS40M4. This result is in contrast to Vibrio cholerae that requires the quorum-sensing regulator HapR to activate the competence regulator QstR. However, similar to V. cholerae, QstR is necessary for transformation in DS40M4. To investigate the difference in transformation frequencies between BB120 and DS40M4, we used previously studied V. cholerae competence genes to inform a comparative genomics analysis coupled with transcriptomics. BB120 encodes homologs of all known competence genes, but most of these genes were not induced by ectopic expression of TfoX, which likely accounts for the non-functional natural transformation in this strain. Comparison of transformation frequencies among Vibrio species indicates a wide disparity among even closely related strains, with Vibrio vulnificus having the lowest functional transformation frequency. We show that ectopic expression of both TfoX and QstR is sufficient to produce a significant increase in transformation frequency in Vibrio vulnificus.
Project description:Vibrio harveyi is an important pathogen in aquaculture, which can cause severe organ damage and metabolic disorders in fish. The organ damage of hybrid grouper caused by Vibrio harveyi was verified through transcriptional analysis.
Project description:Vibrio harveyi is an important pathogen in aquaculture, which can cause severe intestinal damage and metabolic disorders in fish. The intestinal damage of hybrid grouper caused by Vibrio harveyi was verified through transcriptional analysis.
Project description:Vibrio harveyi, a significant pathogen in aquaculture, can lead to severe gut damage and metabolic disorders in fish. Verification via Transcriptome Sequencing of the gut damage caused by Vibrio harveyi in Hybrid Groupers and the Alleviating Effect of oligochitosan Feeding.
Project description:Vibrio harveyi, a significant pathogen in aquaculture, can lead to severe liver damage and metabolic disorders in fish. Verification via Transcriptome Sequencing of the Hepatic Damage Caused by Vibrio harveyi in Hybrid Groupers and the Alleviating Effect of Chitosan Oligosaccharide Feeding.
