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E-GEOD-13325 - Streptococcus agalactiae genes controlled by the MtaR transcription factor

Released on 29 October 2008, last updated on 27 June 2012
Streptococcus agalactiae
Samples (6)
Array (1)
Protocols (8)
The purpose of this study was to determine what S. agalactiae genes are under the control of the MtaR regulatory protein. Inactivation of the Streptococcus agalactiae mtaR gene resulted in the downregulation of 11 genes and the upregulation of 1 gene in the mtaR mutant. Genes involved in the uptake of methionine and a gene involved in the degradation of peptides were downregulated. Also, genes involved in the transport and biosynthesis of arginine were downregulated. The gene encoding the virulence factor cspA was downregulated, as well as a gene showing similarity to plasminogen activators. Thus, the expression of genes involved in both metabolic functions and virulence are under the influence of mtaR. Three cultures of an mtaR insertional mutant (DS101) and three cultures of the isogenic wild-type strain (COH1) were grown in a chemically-defined medium. Cells were disrupted with glass-bead and RNA was isolated by a Trizol method. A custom Affymetrix chip was utilized for microarray analysis. Genes were considered differentially-expressed if they showed a >2.0-fold difference in expression between the strains and a Bayesian (Cyber-T) t-test value of <0.001. The posterior probability of differential expression (PPDE) (< p) value for the genes identified was >0.964.
Experiment type
transcription profiling by array 
Daniel Wilson Shelver <>, Daniel Shelver, Joshua D Bryan, Roxanne Liles
Investigation descriptionE-GEOD-13325.idf.txt
Sample and data relationshipE-GEOD-13325.sdrf.txt
Raw data (1)
Processed data (1)
Array designA-GEOD-7515.adf.txt
R ExpressionSetE-GEOD-13325.eSet.r