Linked Life Data

10692151

Source:http://linkedlifedata.com/resource/pubmed/id/10692151

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2000-4-18
pubmed:abstractText
Plasmid-encoded fimbriae (Pef) expressed by Salmonella typhimurium mediate adhesion to mouse intestinal epithelium. The pef operon shares features with the Escherichia coli pyelonephritis-associated pilus (pap) operon, which is under methylation-dependent transcriptional regulation. These features include conserved DNA GATC box sites in the upstream regulatory region as well as homologues of the PapI and PapB regulatory proteins. Unlike Pap fimbriae, which are expressed in a variety of laboratory media, Pef fimbriae were expressed only in acidic, rich broth under standing culture conditions. Analysis of S. typhimurium grown under these conditions indicated that Pef production was regulated by a phase variation mechanism, in which the bacterial population was skewed between fimbrial expression (phase ON) and non-expression (phase OFF) states. Leucine-responsive regulatory protein (Lrp) and DNA adenine methylase (Dam) were required for pef transcription. In contrast, the histone-like protein (H-NS) and the stationary-phase sigma factor (RpoS) repressed pef transcription. Methylation of the pef GATC II site appeared to be required for pef fimbrial expression based on analysis of a GCTC II mutant that did not express Pef fimbriae. Analysis of the DNA methylation states of pef GATC sites indicated that, under acidic growth conditions, which induced Pef production, most GATC I sites were non-methylated, whereas GATC II and GATC X were predominantly methylated. The methylation protection at GATC I and GATC II was dependent upon Lrp and was modulated by PefI. Together, these results indicate that Pef production is regulated by DNA methylation, which is the first example of methylation-dependent gene regulation outside of E. coli.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0950-382X
pubmed:author
pubmed:issnType
Print
pubmed:volume
35
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
728-42
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
DNA methylation-dependent regulation of pef expression in Salmonella typhimurium.
pubmed:affiliation
Department of Pathology, University of Utah Health Sciences Center, Salt Lake City, UT 84132, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.