Linked Life Data

16531115

Source:http://linkedlifedata.com/resource/pubmed/id/16531115

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4-5
pubmed:dateCreated
2006-7-11
pubmed:abstractText
In this investigation, we identify the CodY protein from Streptococcus pyogenes as a pleiotropic transcription regulator with global features. The notion that acquisition of nutrients by this polyauxotrophic organism is the primary event occurring during the establishment of infection and that virulence expression is a result of this quest, led us to study the action of codY and relA genes on transcriptional gene expression under different nutritional conditions using complex and chemically defined media. Real-time reverse transcription PCR was used to determine the extent to which inactivation of codY and relA affects the mRNA levels of selected transcription factors, virulence genes, transporters, and genes encoding metabolic enzymes. The results show that CodY and RelA did not affect the expression of each other but that both exhibited strong negative autoregulatory properties. Genes negatively controlled by the relA-directed stringent response to amino acid starvation included, besides relA itself, transporters, metabolic enzymes, and at least two virulence genes (graB and speH). The expression of many genes of all four groups studied proved to be subject to direct or indirect control by CodY, often in a nutritional status-dependent fashion. One of the most important results implicates CodY in growth phase-dependent positive transcriptional regulation of pel/sagA and mga, loci that themselves positively affect the expression of numerous virulence factors. Increasing the cellular activity of nicotinamidase in both a codY mutant and wild-type background induced extensive transcriptional reprogramming, altering, among others, the growth phase-dependent transcription pattern of the genes for cysteine protease (speB) and several transporters. Inasmuch as CodY influenced the expression of other regulators (pel/sagA, mga, covRS, ropB, pyrR), its action is amplified and expands the complex regulatory network that governs gene expression in S. pyogenes.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
1438-4221
pubmed:author
pubmed:issnType
Print
pubmed:volume
296
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
259-75
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Linking the nutritional status of Streptococcus pyogenes to alteration of transcriptional gene expression: the action of CodY and RelA.
pubmed:affiliation
Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73190, USA. horst-malke@ouhsc.edu
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural