The Tir-binding region of enterohaemorrhagic Escherichia coli intimin is sufficient to trigger actin condensation after bacterial-induced host cell signalling
UMass Chan Affiliations
Department of Molecular Genetics and MicrobiologyGraduate School of Biomedical Sciences
Document Type
Journal ArticlePublication Date
1999-12-14Keywords
Actins; *Adhesins, Bacterial; Bacterial Adhesion; Bacterial Outer Membrane Proteins; Bacterial Proteins; Binding Sites; Carcinoma, Hepatocellular; *Carrier Proteins; Cell Membrane; Escherichia coli; *Escherichia coli Proteins; Humans; Peptide Fragments; Receptors, Cell Surface; Recombinant Fusion Proteins; Signal Transduction; Tumor Cells, CulturedLife Sciences
Medicine and Health Sciences
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Show full item recordAbstract
Enterohaemorrhagic Escherichia coli (EHEC) has emerged as an important agent of diarrhoeal disease. Attachment to host cells, an essential step during intestinal colonization by EHEC, is associated with the formation of a highly organized cytoskeletal structure containing filamentous actin, termed an attaching and effacing (A/E) lesion, directly beneath bound bacteria. The outer membrane protein intimin is required for the formation of this structure, as is Tir, a bacterial protein that is translocated into the host cell and is thought to function as a receptor for intimin. To understand intimin function better, we fused EHEC intimin to a homologous protein, Yersinia pseudotuberculosis invasin, or to maltose-binding protein. The N-terminal 539 amino acids of intimin were sufficient to promote outer membrane localization of the C-terminus of invasin and, conversely, the N-terminal 489 amino acids of invasin were sufficient to promote the localization of the C-terminus of intimin. The C-terminal 181 residues of intimin were sufficient to bind mammalian cells that had been preinfected with an enteropathogenic E. coli strain that expresses Tir but not intimin. Binding of intimin derivatives to preinfected cells correlated with binding to recombinant Tir protein. Finally, the 181-residue minimal Tir-binding region of intimin, when purified and immobilized on latex beads, was sufficient to trigger A/E lesions on preinfected mammalian cells.Source
Mol Microbiol. 1999 Oct;34(1):67-81.
DOI
10.1046/j.1365-2958.1999.01574.xPermanent Link to this Item
http://hdl.handle.net/20.500.14038/34109PubMed ID
10540286Related Resources
ae974a485f413a2113503eed53cd6c53
10.1046/j.1365-2958.1999.01574.x
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