Linked Life Data

18048936

Source:http://linkedlifedata.com/resource/pubmed/id/18048936

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
Pt 12
pubmed:dateCreated
2007-11-30
pubmed:abstractText
The Gram-positive, spore-forming pathogen Bacillus anthracis is the aetiological agent of anthrax. Its main virulence factors are two toxins and an anti-phagocytic capsule. When B. anthracis is grown in laboratory culture, the highest expression of the anthrax toxin genes occurs during entry into stationary phase, suggesting that nutrient limitation is an environmental cue which induces toxin production. A common bacterial response to starvation is the so-called stringent response, in which the hyperphosphorylated guanosine nucleotide (p)ppGpp is the effector molecule. In Escherichia coli, Bacillus subtilis and other bacteria, accumulation of this molecule leads to down-regulation of stable RNA synthesis and upregulation of the expression of genes involved in survival under nutrient-poor conditions. This study focuses on the stringent response of B. anthracis. We show that in B. anthracis the relA gene is responsible for the synthesis of (p)ppGpp and the stringent down-regulation of stable RNA synthesis upon starvation for the essential amino acids isoleucine, leucine and valine. The deletion of relA did not affect the expression of the virulence gene pagA or virulence in a mouse model of infection. In contrast, spore counts upon growth and sporulation in a defined medium were approximately 10,000-fold lower for the relA deletion mutant than for the parental strain. The contribution of the stringent response to efficient sporulation of B. anthracis is notable, as this suggests that the stringent response may contribute to the persistence of B. anthracis in the natural environment.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
1350-0872
pubmed:author
pubmed:issnType
Print
pubmed:volume
153
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4234-9
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
The stringent response of Bacillus anthracis contributes to sporulation but not to virulence.
pubmed:affiliation
Unité Toxines et Pathogénie Bactérienne, Institut Pasteur, 28 rue du Dr Roux, 75724 Paris Cedex 15, France. w.vanschaik@umcutrecht.nl
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't