Transcription profiling of Streptococcus pneumoniae strain D39, a serotype 2 strain of pneumococcus vs isogenic deletion mutant, (delta)luxS, time series

ABSTRACT: Streptococcus pneumoniae normally resides in the human nasopharynx in a non-disease state. In response to yet unknown triggers it can descend to the lower respiratory tract and/or invade the bloodstream. Regulation and activation of virulence genes play essential roles in this process of disease development. A putative transcriptional regulator in S. pneumoniae, MgrA, with homology to a virulence gene activator, mga, of Group A streptococcus (GAS) was previously identified as being required for development of pneumonia in a murine model. In this work we confirm that mgrA is required for both nasopharyngeal carriage and pneumonia. Transcriptional profiling by microarray technology through the growth course of a strain that bears a deletion of mgrA (AC1500) with that of a strain that over expresses Mgra (AC1481) is used to show that MgrA acts as a repressor of the previously characterized rlrA pathogenicity islet. This is manifested phenotypically by a decrease in adherence to epithelial cells in tissue culture since rlrA pathogenicity islet contains genes mediating adherence.

ORGANISM(S): Streptococcus pneumoniae

SUBMITTER: Elizabeth Joyce 

PROVIDER: E-SMDB-2166 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress