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A Fast and Reliable Pipeline for Bacterial Transcriptome Analysis Case study: Serine-dependent Gene Regulation in Streptococcus pneumoniae
10:18

A Fast and Reliable Pipeline for Bacterial Transcriptome Analysis Case study: Serine-dependent Gene Regulation in Streptococcus pneumoniae

Published on: April 25, 2015

Regulation of gene expression in Streptococcus pneumoniae by response regulator 09 is strain dependent

Wouter T Hendriksen1, Nuno Silva, Hester J Bootsma

  • 1Department of Pediatrics, Erasmus MC-Sophia Children's Hospital, Rotterdam, The Netherlands.

Journal of Bacteriology
|November 7, 2006
PubMed

Insights

Response regulator 09 (RR09) in Streptococcus pneumoniae exhibits strain-specific virulence regulation. Mutants showed altered gene expression, impacting competence and sugar uptake pathways differently between strains D39 and TIGR4.

Area of Science:

  • Microbiology
  • Genetics
  • Molecular Biology

Background:

  • Streptococcus pneumoniae virulence factors are strain-specific.
  • Response regulator 09 (RR09) is implicated in bacterial pathogenesis.
  • Understanding RR09's role is crucial for developing targeted interventions.

Purpose of the Study:

  • To investigate the role of RR09 in Streptococcus pneumoniae virulence.
  • To analyze strain-specific transcriptional changes mediated by RR09.
  • To assess the impact of RR09 on key virulence-associated pathways.

Main Methods:

  • Murine pneumonia infection model.
  • Intranasal infection with wild-type and rr09 mutant strains (TIGR4, D39).
  • Microarray analysis to compare transcriptional profiles.
  • Construction and virulence testing of specific gene mutants (D39Deltasp0063).

Main Results:

  • TIGR4 rr09 mutant (TIGR4Deltarr09) showed attenuated virulence in mice.
  • Microarray analysis revealed distinct transcriptional profiles for D39 and TIGR4 rr09 mutants.
  • Upregulation of competence genes (e.g., comAB) in D39Deltarr09; regulation of rlrA islet genes by RR09 in TIGR4.
  • Downregulation of phosphotransferase systems (PTSs) in D39Deltarr09, but not TIGR4.
  • Mutation in sp0063 did not affect virulence, indicating complex regulation.

Conclusions:

  • RR09 plays a strain-specific role in Streptococcus pneumoniae virulence.
  • RR09 regulates distinct sets of genes, including competence and PTSs, in different strains.
  • Gene expression differences observed in vitro were confirmed in vivo during infection.

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