Transcription profiling of Salmonella typhimurium isolated from mice bone marrow derived macrophages with and without NADPH oxidase
ABSTRACT: NADPH dependent phagocytic oxidase, by producing hydroxyradicals such as hydrogen peroxide, is essential for host defense against Salmonella infection. We used gene array analysis to identify Salmonella enterica serovar Typhimurium genes regulated by NADPH dependent phagocytic oxidase intracellularly in comparison to those expressed in vitro by hydrogen peroxide.
Project description:DNA microarrays were used to provide a global transcriptional profile of S. typhimurium during the intracellular growth phase of infection pathogenesis following infection of macrophages.
Project description:The integration host factor, IHF, is a DNA-binding and -bending protein with roles in local DNA structural organization and transcriptional regulation in Gram-negative bacteria. This heterodimeric protein is composed of the two highly homologous subunits IHF alpha and IHF beta. DNA microarray analysis was used to define the regulon of genes subject to IHF control in Salmonella enterica serovar Typhimurium. The transcription profile of the wild type was compared with those of mutants deficient in IHF alpha, IHF beta, or both IHF alpha and IHF beta. Our data reveal a new connection between IHF and the expression of genes required by the bacterium to undergo the physiological changes associated with the transition from exponential growth to stationary phase. When a mutant lacking IHF entered stationary phase, it displayed downregulated expression of classic stationary-phase genes in the absence of any concomitant change in expression of the RpoS sigma factor. Purified IHF was found to bind to the regulatory regions of stationary-phase genes indicating an auxiliary and direct role for IHF in RpoS-dependent gene activation. Loss of IHF also had a profound influence on expression of the major virulence genes and epithelial cell invasion, indicating a role in co-ordinating regulation of the pathogenic traits with adaptation to stationary phase. Although the three mutants showed considerable overlaps in the genes affected by the ihf lesions, the observed patterns were not identical, showing that S. Typhimurium has not one but three overlapping IHF regulons.
Project description:Array-CGH was done with 5 prostate cancer cell lines and 13 prostate cancer xenografts to create genomic profiles of copy number alterations. The profiles were used to identify common alterations and define minimal regions of copy number changes. A normal female to normal male hybridisation was done to check the experimental conditions.
Project description:Whole genome expression analyses between wild-type Mycobacterium tuberculosis H37Rv and the isogenic mprA::Kmr mutant. Expression analyses between these strains were conducted following growth under physiological conditions, or following exposure to non-inhibitory concentrations of SDS or Triton X-100.
Project description:Gene expression profiling of TRAMP-C2, transgenic adenocarcinoma of mouse prostate, cell line. The experiment was done to see which genes were over- or underexpressed in the cell line. The results were combined with aCGH results of the same samples (experiment Gene copy number profiling of TRAMP-C2 cell line using aCGH) to see, whether the copy number status had any effect on gene expression.