Linked Life Data

10510231

Source:http://linkedlifedata.com/resource/pubmed/id/10510231

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1999-11-4
pubmed:abstractText
Enteropathogenic Escherichia coli (EPEC) secretes several Esps (E. coli-secreted proteins) that are required for full virulence. Insertion of the bacterial protein Tir into the host epithelial cell membrane is facilitated by a type III secretion apparatus, and at least EspA and EspB are required for Tir translocation. An EPEC outer membrane protein, intimin, interacts with Tir on the host membrane to establish intimate attachment and formation of a pedestal-like structure. In this study, we identified a Tir chaperone, CesT, whose gene is located between tir and eae (which encodes intimin). A mutation in cesT abolished Tir secretion into culture supernatants and significantly decreased the amount of Tir in the bacterial cytoplasm. In contrast, this mutation did not affect the secretion of the Esp proteins. The level of tir mRNA was not affected by the cesT mutation, indicating that CesT acts at the post-transcriptional level. The cesT mutant could not induce host cytoskeletal rearrangements, and displayed the same phenotype as the tir mutant. Gel overlay and GST pulldown assays demonstrated that CesT specifically interacts with Tir, but not with other Esp proteins. Furthermore, by using a series of Tir deletion derivatives, we determined that the CesT binding domain is located within the first 100 amino-terminal residues of Tir, and that the pool of Tir in the bacterial cytoplasm was greatly reduced when this domain was disrupted. Interestingly, this domain was not sufficient for Tir secretion, and at least the first 200 residues of Tir were required for efficient secretion. Gel filtration studies showed that Tir-CesT forms a large multimeric complex. Collectively, these results indicate that CesT is a Tir chaperone that may act as an anti-degradation factor by specifically binding to its amino-terminus, forming a multimeric stabilized complex.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0950-382X
pubmed:author
pubmed:issnType
Print
pubmed:volume
33
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1162-75
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:10510231-Amino Acid Sequence, pubmed-meshheading:10510231-Bacterial Proteins, pubmed-meshheading:10510231-Base Sequence, pubmed-meshheading:10510231-Binding Sites, pubmed-meshheading:10510231-DNA, Bacterial, pubmed-meshheading:10510231-DNA Primers, pubmed-meshheading:10510231-Escherichia coli, pubmed-meshheading:10510231-Escherichia coli Proteins, pubmed-meshheading:10510231-Genes, Bacterial, pubmed-meshheading:10510231-HeLa Cells, pubmed-meshheading:10510231-Humans, pubmed-meshheading:10510231-Macromolecular Substances, pubmed-meshheading:10510231-Molecular Chaperones, pubmed-meshheading:10510231-Molecular Sequence Data, pubmed-meshheading:10510231-Mutation, pubmed-meshheading:10510231-RNA, Bacterial, pubmed-meshheading:10510231-RNA, Messenger, pubmed-meshheading:10510231-Receptors, Cell Surface, pubmed-meshheading:10510231-Sequence Deletion, pubmed-meshheading:10510231-Transcription, Genetic, pubmed-meshheading:10510231-Virulence
pubmed:year
1999
pubmed:articleTitle
Enteropathogenic Escherichia coli translocated intimin receptor, Tir, requires a specific chaperone for stable secretion.
pubmed:affiliation
Biotechnology Laboratory, University of British Columbia, Vancouver, BC, Canada V6T 1Z3.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't