Project description:We wanted to identify genes regulated by the two-component signal transduction system RR/HK06 in Streptococcus pneumoniae. We used microarray in order to discover regulated genes, investigating the effects of the over-expression of RR06 in TIGR4 (serotype 4). Keywords: Gene Regulation
Project description:We wanted to identify genes regulated by the two-component signal transduction system RR/HK06 in Streptococcus pneumoniae. We used microarray in order to discover regulated genes, investigating the effects of the over-expression of RR06 in D39 (serotype 2). Keywords: Gene Regulation
Project description:The polyamine transport operon in Streptococcus pneumoniae TIGR4 is necessary for survival in murine models of pneumococcal pneumonia. To date, there is no description of polyamine transport dependent pneumococcal gene expression. In this study, we compared gene expression between the wild-type and transport deficient (potABCD) TIGR4 by RNA-Seq analysis.
Project description:The polyamine biosynthesis gene, speE, in Streptococcus pneumoniae TIGR4 is necessary for survival in murine models of pneumococcal pneumonia. To date, there is no description of polyamine biosynthesis dependent pneumococcal gene expression. In this study, we compared gene expression between the wild-type and biosynthesis deficient (speE) TIGR4 by RNA-Seq analysis.
Project description:The aim of this experiment is to determine the difference in protein expression, if any, in a mouse model of pneumococcal pneumonia using wild type and a polyamine transport operon deletion mutant strain of S. pneumoniae TIGR4, using expression proteomics. Eight week old female C57bl/6 mice were used in this study. The experimental design had two groups of 3 animals each that were administered 50 µL 1 X 107 CFU wild type S. pneumoniae TIGR4 or S. pneumoniae TIGR4 ΔpotABCD strain by intranasal instillation. The control group with three animals received 50 µL PBS. Mice were euthanized 4 hr and 12 hr post infection and lung tissues were harvested. The control group animals were euthanized 12 hr post infection.
Project description:We used a combination of adherence assays, mutagenesis and functional genomics to identify novel factors involved in adherence. This work identifies a list of novel potential pneumococcal adherence determinants. S. pneumoniae TIGR4 transcriptome was sequenced using RNA-Seq on the Illumina GA. High-quality, single ended, 36bp reads were mapped to the TIGR4 genome.
Project description:Recent murine studies have demonstrated that the role of response regulator 09 (RR09) of S. pneumoniae in virulence varies between strains. In the present study, we used a murine pneumonia model of infection to assess the virulence of a TIGR4 rr09-mutant, and found that TIGR4Δrr09 was attenuated after intranasal infection. Further, we investigated the in vitro transcriptional changes in pneumococcal rr09 mutants of two strains, D39 and TIGR4, by microarray analysis. The transcriptional profiles of the rr09 mutants in both strains displayed clear differences compared to their parental wild-type. In D39Δrr09 but not TIGR4Δrr09, genes involved in competence (e.g. comAB) were upregulated. In TIGR4, genes located on the rlrA pathogenicity islet, absent in the D39 genome, appeared to be regulated by RR09. Furthermore, several phosphotransferase systems (PTSs), believed to be involved in sugar uptake (e.g., sp0060-sp0066), were strongly downregulated in D39Δrr09, while not regulated by RR09 in TIGR4. To address the role of one of these PTS in virulence, D39Δsp0063 was constructed and tested in a murine infection model. No difference in virulence compared to the wild-type was found, indicating that downregulation of this gene alone is not the cause of the avirulent phenotype of D39Δrr09. Finally, expression of rr09 and three of our identified RR09 targets were assessed during infection in mice. This in vivo experiment confirmed differences in expression between TIGR4 wild-type and rr09-mutant, as well as between wild-type D39 and TIGR4. In conclusion, our results indicate strain specific regulation of pneumococcal gene expression by RR09. Keywords: Genetic modification
Project description:Recent murine studies have demonstrated that the role of response regulator 09 (RR09) of S. pneumoniae in virulence varies between strains. In the present study, we used a murine pneumonia model of infection to assess the virulence of a TIGR4 rr09-mutant, and found that TIGR4Δrr09 was attenuated after intranasal infection. Further, we investigated the in vitro transcriptional changes in pneumococcal rr09 mutants of two strains, D39 and TIGR4, by microarray analysis. The transcriptional profiles of the rr09 mutants in both strains displayed clear differences compared to their parental wild-type. In D39Δrr09 but not TIGR4Δrr09, genes involved in competence (e.g. comAB) were upregulated. In TIGR4, genes located on the rlrA pathogenicity islet, absent in the D39 genome, appeared to be regulated by RR09. Furthermore, several phosphotransferase systems (PTSs), believed to be involved in sugar uptake (e.g., sp0060-sp0066), were strongly downregulated in D39Δrr09, while not regulated by RR09 in TIGR4. To address the role of one of these PTS in virulence, D39Δsp0063 was constructed and tested in a murine infection model. No difference in virulence compared to the wild-type was found, indicating that downregulation of this gene alone is not the cause of the avirulent phenotype of D39Δrr09. Finally, expression of rr09 and three of our identified RR09 targets were assessed during infection in mice. This in vivo experiment confirmed differences in expression between TIGR4 wild-type and rr09-mutant, as well as between wild-type D39 and TIGR4. In conclusion, our results indicate strain-specific regulation of pneumococcal gene expression by RR09. Keywords: genetic modification