Project description:Bdellovibrio bacteriovorus is a Gram-negative bacterium that is a pathogen of other Gram-negative bacteria, including many bacteria which are pathogens of humans, animals and plants. As such Bdellovibrio has potential as a biocontrol agent, or living antibiotic. B. bacteriovorus HD100 has a large genome and it is not yet known which of it encodes the molecular machinery and genetic control of predatory processes. We have tried to fill this knowledge-gap using mixtures of predator and prey mRNAs to monitor changes in Bdellovibrio gene expression at a timepoint of early-stage prey infection and prey killing in comparison to control cultures of predator and prey alone and also in comparison to Bdellovibrio growing axenically (in a prey-or host independent “HI” manner) on artificial media containing peptone and tryptone. From this we have highlighted genes of the early predatosome with predicted roles in prey killing and digestion and have gained insights into possible regulatory mechanisms as Bdellovibrio enter and establish within the prey bdelloplast. Approximately seven percent of all Bdellovibrio genes were significantly up-regulated at 30 minutes of infection- but not in HI growth- implicating the role of these genes in prey digestion. Five percent were down-regulated significantly, implicating their role in free-swimming, attack-phase physiology. This study gives the first post- genomic insight into the predatory process and reveals some of the important genes that Bdellovibrio expresses inside the prey bacterium during the initial attack. Keywords: Transcriptional analysis
Project description:Bdellovibrio bacteriovorus 109J is a predatory bacterium which lives by predating on other Gram-negative bacteria to obtain the nutrients it needs for replication and survival. Here, we evaluated the effects a bacterial signaling molecule called diffusible signaling factor (DSF) have on B. bacteriovorus 109J transcriptomics.
Project description:Bdellovibrio bacteriovorus is a Gram-negative bacterium that is a pathogen of other Gram-negative bacteria, including many bacteria which are pathogens of humans, animals and plants. As such Bdellovibrio has potential as a biocontrol agent, or living antibiotic. B. bacteriovorus HD100 has a large genome and it is not yet known which of it encodes the molecular machinery and genetic control of predatory processes. We have tried to fill this knowledge-gap using mixtures of predator and prey mRNAs to monitor changes in Bdellovibrio gene expression at a timepoint of early-stage prey infection and prey killing in comparison to control cultures of predator and prey alone and also in comparison to Bdellovibrio growing axenically (in a prey-or host independent âHIâ manner) on artificial media containing peptone and tryptone. From this we have highlighted genes of the early predatosome with predicted roles in prey killing and digestion and have gained insights into possible regulatory mechanisms as Bdellovibrio enter and establish within the prey bdelloplast. Approximately seven percent of all Bdellovibrio genes were significantly up-regulated at 30 minutes of infection- but not in HI growth- implicating the role of these genes in prey digestion. Five percent were down-regulated significantly, implicating their role in free-swimming, attack-phase physiology. This study gives the first post- genomic insight into the predatory process and reveals some of the important genes that Bdellovibrio expresses inside the prey bacterium during the initial attack. Keywords: Transcriptional analysis 3 replicates of attack phase cells and 3 replicates of 30 minutes post-infection cells were analysed on individual arrays. Replicate 3 was normalized separately.
Project description:The transcriptional response of E. coli being predated by Bdellovibrio bacteriovorus Keywords: Transcriptional analysis 5 biological replicates with 2 technical replicates each of E. coli cells only and E. coli cells 15 minutes post-infection arrays 4 arrays, with samples swapped for each biological replicate. Gel image files generated by the ImageQuant scanning software. Each raw data txt file has the "control" samples which are the E. coli samples reading on the entire array and thus with the 2 technical replicates, and the "data" samples to which it is compared by Arrayvision. the "data" samples of ec1 to ec5 are Bdellovibrio only controls 2 technical replicates). The "data" samples of t1 to t5 are the test samples. Hence t1 to t5 are the raw data files for samples test1 to test10 and ec1 to ec5 are the raw data files for all of samples ec-1 to ec-10 and bd-1 to bd-10.