Binding of intimin from enteropathogenic Escherichia coli to Tir and to host cells

Elizabeth L. Hartland, Miranda Batchelor, Robin M. Delahay, Christine Hale, Stephen Matthews, Gordon Dougan, Stuart Knutton, Ian Connerton, Gad Frankel

Research output: Contribution to journalArticleResearchpeer-review

165 Citations (Scopus)

Abstract

Enteropathogenic Escherichia coli (EPEC) induce characteristic attaching and effacing (A/E) lesions on epithelial cells. This event is mediated, in part, by binding of the bacterial outer membrane protein, intimin, to a second EPEC protein, Tir (translocated intimin receptor), which is exported by the bacteria and integrated into the host cell plasma membrane. In this study, we have localized the intimin-binding domain of Tir to a central 107-amino-acid region, designated Tir-M. We provide evidence that both the amino- and carboxy-termini of Tir are located within the host cell. In addition, using immunogold labelling electron microscopy, we have confirmed that intimin can bind independently to host cells even in the absence of Tir. This Tir-independent interaction and the ability of EPEC to induce A/E lesions requires an intact lectin-like module residing at the carboxy-terminus of the intimin polypeptide. Using the yeast two-hybrid system and gel overlays, we show that intimin can bind both Tir and Tir-M even when the lectin-like domain is disrupted. These data provide strong evidence that intimin interacts not only with Tir but also in a lectin-like manner with a host cell intimin receptor.

Original languageEnglish
Pages (from-to)151-158
Number of pages8
JournalMolecular Microbiology
Volume32
Issue number1
DOIs
Publication statusPublished - 19 Apr 1999
Externally publishedYes

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