title: The Hek outer membrane protein of Escherichia coli is an auto-aggregating adhesin and invasin.
abstract: Escherichia coli is the principal gram-negative causative agent of sepsis and meningitis in neonates. The pathogenesis of meningitis due to E. coli K1 involves mucosal colonization, transcytosis of epithelial cells, survival in the blood stream and eventually invasion of the meninges. The latter two aspects have been well characterized at a molecular level in the last decade. Less is known about the early stages of pathogenesis, i.e. adhesion to and invasion of gastrointestinal cells. Here, the characterization of the Hek protein is reported, which is expressed by neonatal meningitic E. coli (NMEC) and is localized to the outer membrane. It is demonstrated that this protein can cause agglutination of red blood cells and can mediate autoaggregation. Escherichia coli expressing this protein can adhere to and invade epithelial cells. So far, this is the first outer membrane protein in NMEC to be directly implicated in epithelial cell invasion.
authors.affiliation: Department of Microbiology, Moyne Institute, Trinity College Dublin, Dublin, Ireland.
authors.forename: Robert P
authors.initials: RP
authors.lastname: Fagan
authors.forename: Stephen G J
authors.initials: SG
authors.lastname: Smith
mesh_terms: D018829:Adhesins, Bacterial; D018830:Adhesins, Escherichia coli / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001422:Bacterial Adhesion; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D016466:CHO Cells; D002460:Cell Line; D006224:Cricetinae; D003412:Cricetulus; D004847:Epithelial Cells / Q000382:microbiology*; D004912:Erythrocytes / Q000382:microbiology; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity* / Q000502:physiology; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D006384:Hemagglutination; D006801:Humans; D007231:Infant, Newborn; D020814:Meningitis, Escherichia coli / Q000382:microbiology
chemical_list: D018829:Adhesins, Bacterial; D018830:Adhesins, Escherichia coli; D001425:Bacterial Outer Membrane Proteins; D029968:Escherichia coli Proteins; C520238:HEK protein, E coli