Identification of competence pheromone responsive genes in Streptococcus pneumoniae by use of DNA microarrays

摘要: Summary Natural genetic transformation in Streptococcus pneumoniae is controlled part by a quorum-sensing system mediated peptide pheromone called competence-stimulating (CSP), which acts to coordinate transient activation of genes required for competence. To characterize the transcriptional response and regulatory events occurring when cells are exposed competence pheromone, we constructed DNA microarrays analysed temporal expression profiles 1817 among 2129 unique predicted open reading frames present S. TIGR4 genome (84%). After CSP stimulation, responsive exhibited four temporally distinct profiles: early, late delayed gene induction, repression. At least eight early participate regulation including comX, encodes an alternative sigma factor. Late were dependent on ComX CSP-induced expression, many playing important roles transformation. Genes class (third wave) appear be stress related. repressed during include ribosomal protein loci other involved synthesis. This study increased number identified CSP-responsive from approximately 40 188. Given relatively large induced (6% genome), it was interest determine provide functions essential Many subjected disruption mutagenesis, allowing us establish that 124 CSP-inducible genes, 67 individually dispensable transformation, whereas 23