Project description:YerA41 is a myoviridae bacteriophage that was originally isolated due its ability to infect Yersinia ruckeri bacteria, the causative agent of enteric redmouth disease of salmonid fish. Several attempts to determine its genomic DNA sequence using traditional and next generation sequencing technologies failed, indicating that the phage genome is modified such way that it is an unsuitable template for PCR amplification and sequencing. To determine the YerA41 genome sequence we isolated RNA from phage-infected Y. ruckeri cells at different time points post-infection, and sequenced it. The host-genome specific reads were substracted and de novo assembly was performed on the unaligned reads.
Project description:Characterization of the renal transcriptomic response to Yersinia ruckeri/Conseuqences of early life stage thyroid suppression on long-term immune function and the immune response in the fathead minnow (Pimephales promelas)
Project description:Bacteriophages are potent therapeutics against biohazardous bacteria that are rapidly acquiring multidrug resistance. However, routine administration of bacteriophage therapy is currently impeded by a lack of safe phage production methodologies and insufficient phage characterization. We thus developed a versatile cell-free platform for host-independent production of phages targeting gram-positive and gram-negative bacteria. A few microliters of a one-pot reaction produces effective doses of phages against potentially antibiotic-resistant bacteria such as enterohemorrhagic E. coli (EAEC) and Yersinia pestis, which also possibly pose threats as biological warfare agents. We also introduce a method for transient, non-genomic phage engineering to safely confer additional functions, such as a purification tag or bioluminescence for host detection, for only one replication cycle. Using high-resolution and time-resolved mass spectrometry, we validated the expression of 40 hypothetical proteins from two different phages (T7 and CLB-P3) and identified genes in the genome of phage T7 that express exceptionally late during phage replication. Our comprehensive methodology thus allows for accelerated reverse and forward phage engineering as well as for safe and customized production of clinical-grade therapeutic bacteriophages.
Project description:Juvenile rainbow trout were exposed to two different concentrations of 17β-estradiol (E2) (2 or 20 mg/kg feed), and then infected with three concentrations of Yersinia ruckeri, a bacterial pathogen causing massive losses in wild and farmed salmonid populations. Infection with Y. ruckeri caused mortality of trout, and this effect was significantly enhanced by simultaneous exposure to high E2 dose. Analysis of hepatic gene expression profiles revealed complex regulations of pathways involved in immune responses, stress responses and detoxicification pathways. E2 markedly reduced expression of several genes implicated in xenobiotic metabolism. The results suggest that the interaction between pathogen and E2 interfered with the fish’s capability of clearing toxic compounds. The findings of the current study add to our understanding of multiple exposure responses in fish.
Project description:RNA-sequencing was preformed from RNA isolated from bacteria infected with the bacteriophage. In order to reveal the phage-host interactions between φR1-37 and Yersinia enterocolitica throughout the phage infection cycle, both the transcriptomes were scrutinized during all the stages of infection.
Project description:Juvenile rainbow trout were exposed to two different concentrations of 17M-NM-2-estradiol (E2) (2 or 20 mg/kg feed), and then infected with three concentrations of Yersinia ruckeri, a bacterial pathogen causing massive losses in wild and farmed salmonid populations. Infection with Y. ruckeri caused mortality of trout, and this effect was significantly enhanced by simultaneous exposure to high E2 dose. Analysis of hepatic gene expression profiles revealed complex regulations of pathways involved in immune responses, stress responses and detoxicification pathways. E2 markedly reduced expression of several genes implicated in xenobiotic metabolism. The results suggest that the interaction between pathogen and E2 interfered with the fishM-bM-^@M-^Ys capability of clearing toxic compounds. The findings of the current study add to our understanding of multiple exposure responses in fish. Microarray analyses compared 3 groups of pathogen infected fish: no estrogen treatment (NE2), low (LE2) and high (HE2) doses of hormone