Linked Life Data

19684070

Source:http://linkedlifedata.com/resource/pubmed/id/19684070

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
Pt 11
pubmed:dateCreated
2009-11-2
pubmed:abstractText
Shiga-toxigenic Escherichia coli (STEC) colonizing the bowel are exposed to a variety of short-chain fatty acids (SCFAs), including acetate, propionate and butyrate, produced by gut microflora. However, the total concentrations and relative amounts of SCFAs in the lumen vary with intestinal niche. Here we report that conditions simulating SCFA concentrations present in the human gut trigger expression of the iha gene, which encodes an adherence-conferring outer-membrane protein of pathogenic E. coli. We show that growth under conditions simulating colonic, but not ileal, SCFA concentrations increases iha expression in three tested STEC strains, with the strongest expression detected in LEE-negative STEC O113:H21 strain 98NK2. Expression of iha is known to be subject to Fur-mediated iron repression in O157:H7 STEC, and the same occurs in 98NK2. However, exogenous iron did not repress iha expression in the presence of colonic SCFAs in either 98NK2 or the O157:H7 strain EDL933. Moreover, exposure to the iron chelator 2,2'-dipyridyl caused no further enhancement of iha expression over that induced by colonic SCFAs. These findings indicate that SCFAs regulate iha expression in STEC independently of iron. Increased expression of iha under colonic but not ileal SCFA conditions possibly may contribute to preferential colonization of the human colon by STEC.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1465-2080
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
155
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3554-63
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Differential effects of short-chain fatty acids and iron on expression of iha in Shiga-toxigenic Escherichia coli.
pubmed:affiliation
Research Centre for Infectious Diseases, School of Molecular and Biomedical Science, University of Adelaide, South Australia, 5005, Australia.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't