Project description:The gene expression of Salmonella enterica Typhimurium MB282 residing in the food vacuole (phagosome) of Tetrahymena was analyzed by microarray.
Project description:au07-07_salmonella - infection with Salmonella or Pseudomonas or E. coli. Identification of genes involved in early Arabidopsis response to pathogenic and non-pathogenic bacteria. Arabidopsis thaliana Col-0 seedlings were infected for 2 hours with a) Salmonella typhimurium strain 14028s, b) Pseudomonas syringae DC3000 or c) Escherichia coli DH5A Keywords: treated vs untreated comparison
Project description:We report the application of RNA sequencing to assess the expression dynamics of miRNAs and their isoforms over time upon infection with a panel of six intracellular bacteria (Mycobacterium tuberculosis H37Rv, Mycobacterium tuberculosis Beijing strain GC1237, Mycobacterium bovis BCG, Salmonella typhimurium strain Keller, Staphloccocus epidermidis and Yersinia pseudotuberculosis)
Project description:We used microarrays to detail the global programme of gene expression in human macrophages infected in vitro with HIV-1 or not and then subjected to contact with Salmonella Typhimurium ST313 or ST19 strains; we identified distinct classes of differentially regulated genes during this process
Project description:au07-07_salmonella - infection with Salmonella or Pseudomonas or E. coli. Identification of genes involved in early Arabidopsis response to pathogenic and non-pathogenic bacteria. Arabidopsis thaliana Col-0 seedlings were infected for 2 hours with a) Salmonella typhimurium strain 14028s, b) Pseudomonas syringae DC3000 or c) Escherichia coli DH5A Keywords: treated vs untreated comparison 6 dye-swap - CATMA arrays
Project description:DNA supercoiling is essential for all living cells because it controls all processes involving DNA. In bacteria, global DNA supercoiling results from the opposing activities of topoisomerase I, which relaxes DNA, and DNA gyrase, which compacts DNA. These enzymes are widely conserved, sharing >91% amino acid identity between the closely related species Escherichia coli and Salmonella enterica serovar Typhimurium. Why, then, do E. coli and Salmonella exhibit different DNA supercoiling when experiencing the same conditions? We now report that this surprising difference reflects disparate activation of their DNA gyrases by the polyamine spermidine and its precursor putrescine. In vitro, Salmonella DNA gyrase activity was sensitive to changes in putrescine concentration within the physiological range, whereas activity of the E. coli enzyme was not. In vivo, putrescine activated the Salmonella DNA gyrase and spermidine the E. coli enzyme. High extracellular Mg2+ decreased DNA supercoiling exclusively in Salmonella by reducing the putrescine concentration. Our results establish the basis for the differences in global DNA supercoiling between E. coli and Salmonella, define a signal transduction pathway regulating DNA supercoiling, and identify potential targets for antibacterial agents.
Project description:Longitudinal analysis of Salmonella typhimurium mRNA from superspeader mouse cecal content and stool compared to in vitro Salmonella typhimurium mRNA.
Project description:OmpR is a DNA binding protein belonging to the OmpR/EnvZ two component system. This system is known to sense changes in osmolarity in Escherichia coli. Recently, OmpR in Salmonella enterica serovar Typhimurium was found to be activated by acidic pH and DNA relaxation. In this study, ChIP-on-chip was employed to ascertain the genome-wide distribution of OmpR in Salmonella Typhimurium and Escherichia coli in acidic and neutral pH. In addition we investigated the affect of DNA relaxation on OmpR binding in Salmonella Typhimurium.
Project description:Bacterial pathogens rapidly change and adapt their proteome to cope with the environment in host cells and secret effector proteins to hijack host targets to ensure their survival and proliferation during infection. Excessive host proteins make it difficult to profile pathogens’ proteome dynamics by conventional proteomics. It is even more challenging to map pathogen-host protein-protein interactions in real time, given the low abundance of bacterial effectors and weak and transient interactions they may be involved. Here, we report a method for selectively labeling of bacterial proteome using a bifunctional amino acid, photo-ANA, equipped with a bioorthogonal handle and a photoreactive warhead, which enables simultaneous analysis of bacterial proteome reprogramming and pathogen-host protein interactions of Salmonella Typhimurium during infection. Using photo-ANA, we discovered temporal and distinct protein synthesis changes inside host cells and identified FLOT1/2 as the novel host interactors of Salmonella Typhimurium effector PipB2 in late stage of infection.
