title: Retraction of enteropathogenic E. coli type IV pili promotes efficient host cell colonization, effector translocation and tight junction disruption.
abstract: Type IV pili (Tfp) play a primary role in mediating the adherence of pathogenic bacteria to their hosts. The pilus filament can retract with an immense force. However, the role of this activity in microbial pathogenesis has not been rigorously explored. Experiments performed on volunteers suggested that the retraction capacity of enteropathogenic Escherichia coli (EPEC) Tfp is required for full virulence. Here we review our recent study(1) in which we showed that the retraction capacity of the EPEC Tfp facilitates tight-junction disruption and actin-rich pedestal formation by promoting efficient bacterial protein effector translocation into epithelial host cells. We also present new data using live imaging confocal microscopy suggesting that EPEC adheres to monolayers in microcolonies and that Tfp retraction facilitates significant changes in the microcolony shape, which may be critical for efficient effector delivery. Our studies hence suggest novel insights into the role of pili retraction in EPEC pathogenesis.
authors.affiliation: Department of Cell and Developmental Biology, Institute of Life Sciences, Hebrew University of Jerusalem, Jerusalem, Israel. aroeti@cc.huji.ac.il
authors.forename: Benjamin
authors.initials: B
authors.lastname: Aroeti
authors.forename: Gil
authors.initials: G
authors.lastname: Friedman
authors.forename: Efrat
authors.initials: E
authors.lastname: Zlotkin-Rivkin
authors.forename: Michael S
authors.initials: MS
authors.lastname: Donnenberg
mesh_terms: D000818:Animals; D001422:Bacterial Adhesion; D002460:Cell Line; D054308:Enteropathogenic Escherichia coli / Q000472:pathogenicity*; D004847:Epithelial Cells / Q000382:microbiology*; D029968:Escherichia coli Proteins / Q000378:metabolism; D010861:Fimbriae, Bacterial / Q000378:metabolism*; D006801:Humans; D008853:Microscopy; D021381:Protein Transport; D019108:Tight Junctions / Q000382:microbiology*; D014774:Virulence; D037521:Virulence Factors / Q000378:metabolism*
chemical_list: D029968:Escherichia coli Proteins; D037521:Virulence Factors