Linked Life Data

18248436

Source:http://linkedlifedata.com/resource/pubmed/id/18248436

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2008-2-18
pubmed:abstractText
The Salmonella SpvB protein possesses ADP-ribosyl transferase activity. SpvB, acting as an intracellular toxin, covalently modifies monomeric actin, leading to loss of F-actin filaments in Salmonella-infected human macrophages. Using defined Salmonella mutants, different functional components of the SPI-2 type three secretion system (TTSS), ssaV, spiC, sseB, sseC, and sseD, were found to be required for SpvB-mediated actin depolymerization in human macrophages. Expression of SpvB protein in Salmonella was not affected by any of the SPI-2 mutants and the effects of these loci were not due to reduced numbers of intracellular bacteria. Interestingly, the major SPI-2 virulence effector, SifA, is not required for SpvB action. Further, caspase-3 activation is an additional marker of cytotoxicity in Salmonella-infected human macrophages. Caspase-3 activity depended on SpvB and SPI-2 TTSS function, but not on SifA. These human macrophage cell culture results were corroborated by virulence studies in mice. Using competitive infection of mice with mixed inocula of single and double mutants, spvBmut1 mutation did not have an effect independent of ssaJ mutation, essential for SPI-2 TTSS function. In contrast, competitive infection studies in mice confirmed that SpvB and SifA have independent virulence effects, as predicted by the macrophage studies.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0928-8244
pubmed:author
pubmed:issnType
Print
pubmed:volume
52
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
194-201
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Identification of Salmonella SPI-2 secretion system components required for SpvB-mediated cytotoxicity in macrophages and virulence in mice.
pubmed:affiliation
Department of Medicine 0640, School of Medicine, University of California at San Diego, La Jolla, CA 92093-0640, USA. shbrowne@ucsd.edu
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural