Project description:FabR ChIP-chip on Salmonella enterica subsp. enterica serovar Typhimurium SL1344 using anti-Myc antibody against strain with chromosomally 9Myc-tagged FabR (IP samples) and wildtype strain (mock IP samples)
Project description:To investigate the effects of MccY on Salmonella Typhimurium, Ton system genes mutants were constructed and RNA-seq analysis were performed.
Project description:Investigation of whole genome gene expression level changes in a Salmonella enterica serovar Typhimurium UK1 delta-iacP mutant, compared to the wild-type strain. IacP is resoponsible for the secretion of virulence effector proteins via the type III secretion system, thereby contributing the virulence of S. Typhimurium. The mutants analyzed in this study are further described in Kim et al. 2011. Role of Salmonella Pathogenicity Island 1 Protein IacP in Salmonella enterica Serovar Typhimurium Pathogenesis. Infection and Immunity 79(4):1440-1450 (PMID 21263021).
Project description:Investigation of whole genome gene expression level changes in a Salmonella enterica serovar Typhimurium 14028 delta GidA mutant The mutant described in this study is further analyzed in Shippy, D. C., N. M. Eakley, P. N. Bochsler, and A. A. Fadl. 2011. Biological and virulence characteristics of Salmonella enterica serovar Typhimurium following deletion of glucose-inhibited division (gidA) gene. Microb Pathog.
Project description:Bifidobacterium thermophilum RBL67 (RBL67), a human fecal isolate and promising probiotic candidate, showed antagonistic and protective effects against Salmonella and Listeria in vitro. However, the underlying mechanisms fostering these health-related effects remain unknown. Therefor the transcriptome response of RBL67 and Salmonella enterica subsp. enterica serovar Typhimurium N-15 (N-15) in co-culture compared to the response in their respective mono-cultures. RNA was extracted from culture samples taken after 4 (N-15) or 5 h (RBL67) and RNAseq was performed on an Illumina HiSeq 2000 sequencer. Three biological replciates were performed resulting in 12 data sets: 3 RBL67 mono culture, 3 N15 mono-culture, 3 RBL67 co-culture, 3 N15 co-culture. Our study provided first insights into probiotic-pathogen interaction on transcriptional level and suggests a mechanism for how probiotic organisms can protect the host from infections.
Project description:Infection with Salmonella enterica serovar Typhi in humans causes the systemic, life-threatening disease typhoid fever. In the laboratory, typhoid fever can be modeled through the inoculation of susceptible mice with Salmonella enterica serovar Typhimurium. The ensuing disease is characterized by systemic dissemination and colonization of many organs, including the liver, spleen and gallbladder. Using this murine model, we previously characterized the interactions between Salmonella Typhimurium and host cells in the gallbladder and showed that this pathogen can successfully invade gallbladder epithelial cells and proliferate. Additionally, we showed that Salmonella Typhimurium can use bile phospholipids to grow at high rates. These abilities are likely important for quick colonization of the gallbladder during typhoid fever and further pathogen dissemination through fecal shedding. To further characterize the interactions between Salmonella and the gallbladder environment we compared the transcriptome of Salmonella cultures grown in LB or physiological murine bile. Our data showed that many genes involved in bacterial central metabolism are affected by bile, with the citric acid cycle being repressed and alternative respiratory systems being activated. Additionally, our study revealed a new aspect of Salmonella interactions with bile through the identification of phoP as a bile-responsive gene. Repression of phoP expression does not involve PhoPQ sensing of a bile component. Due to its critical role in Salmonella virulence, further studies in this area will likely reveal aspects of the interaction between Salmonella and bile that are relevant to disease.
Project description:Bacterial transcription networks typically consist of hundreds of transcription factors and thousands of promoters. However, current attempts to map bacterial promoters have failed to report the true complexity of bacterial transcription. The differential RNA-seq (dRNA-seq) approaches only identified a subset of promoters because they involved few growth conditions. Here, we present a simplified approach for global promoter identification in bacteria, based upon the analysis of RNA-seq data from multiple environmental conditions. RNA was extracted from Salmonella enterica serovar Typhimurium (S. Typhimurium) grown in 22 different environmental conditions, which were devised to reflect the pathogenic lifestyle of S. Typhimurium. Individual RNA samples were combined into two pools for sequencing. In just two runs of strand-specific RNA-seq and dRNA-seq of the pooled sample we identified 3701 promoters (Pool sample). In further experiments, we found that individual in vitro conditions stimulate the expression of about 60% of the S. Typhimurium genome, whereas the suite of 22 conditions induced expression of 87% of S. Typhimurium genes. We discovered environmental conditions that induce many genes within Salmonella pathogenicity islands and identified 78 new sRNAs. In S. Typhimurium there is now experimental evidence for 280 sRNAs, and we classified them in terms of location and Hfq-binding.
Project description:Summary: Salmonella enterica serovar Typhimurium strain 14028s transcriptome response to tomato medium (TM) and tomato root exudates (TX) compared to minimal medium (MM). Purpose: Salmonella mRNA profile, when grown in different media was compared to minimal medium to reveal environment specific transcriptional changes. Methods: mRNA profiles were generated using Illumina HiSeq in triplicates. The sequences were analysed using Bowtie2 followed by Cufflinks.