Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

MgrA acts as a repressor of the rlrA pathogenicity islet

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 . This is manifested phenotypically by a decrease in adherence to epithelial cells in tissue culture since rlrA pathogenicity islet contains genes mediating adherence. Set of arrays organized by shared biological context, such as organism, tumors types, processes, etc. Computed

ORGANISM(S): Streptococcus pneumoniae

SUBMITTER: Elizabeth Joyce

PROVIDER: E-GEOD-3107 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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MgrA, an orthologue of Mga, Acts as a transcriptional repressor of the genes within the rlrA pathogenicity islet in Streptococcus pneumoniae.

Hemsley Carolyn C Joyce Elizabeth E Hava David L DL Kawale Amita A Camilli Andrew A

Journal of bacteriology 20031101 22

Streptococcus pneumoniae normally resides in the human nasopharynx in a nondisease state. In response to unknown triggers this organism 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. Characterization of S. pneumoniae regulatory networks has been a recent area of interest, but despite inroads little is known about regulation of virulence genes in this pathogen. A pu ...[more]

PMID: 14594838

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Dataset Information

MgrA acts as a repressor of the rlrA pathogenicity islet

Publications

MgrA, an orthologue of Mga, Acts as a transcriptional repressor of the genes within the rlrA pathogenicity islet in Streptococcus pneumoniae.

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