title: The locus of enterocyte effacement pathogenicity island of enteropathogenic Escherichia coli encodes secretion functions and remnants of transposons at its extreme right end.
abstract: The locus of enterocyte effacement (LEE) is necessary for enteropathogenic Escherichia coli to cause characteristic attaching and effacing lesions in host cells. To determine whether sequences at the extreme right end of the LEE downstream of the espB gene are required for attaching and effacing, we constructed a mutant with an omega-interposon insertion immediately downstream of espB. This mutant is incapable of attaching and effacing, of secreting EspA and EspB and of inducing tyrosine phosphorylation of host cell proteins. These phenotypes are restored by a plasmid containing the extreme right end of the LEE. The nucleotide sequence of this region reveals a relatively low G+C content, remnants of transposons, and several open reading frames. The predicted products of these open reading frames include a potential chaperone, a potential component of the secretion apparatus, and a hypothetical peptide with proline rich repeats reminiscent of several eukaryotic proteins. These data indicate that the extreme right end of the LEE is required for attaching and effacing and reveal information relevant to the origin and function of the LEE.
authors.affiliation: Department of Medicine, University of Maryland School of Medicine, Baltimore 21201, USA. mdonnenb@umabnet.ab.umd.edu
authors.forename: M S
authors.initials: MS
authors.lastname: Donnenberg
authors.forename: L C
authors.initials: LC
authors.lastname: Lai
authors.forename: K A
authors.initials: KA
authors.lastname: Taylor
mesh_terms: D000595:Amino Acid Sequence; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D003001:Cloning, Molecular; D004251:DNA Transposable Elements / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics / Q000472:pathogenicity*; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial / Q000235:genetics*; D018832:Molecular Chaperones / Q000378:metabolism; D008969:Molecular Sequence Data; D016296:Mutagenesis / Q000235:genetics; D009154:Mutation / Q000235:genetics; D016366:Open Reading Frames / Q000235:genetics; D010641:Phenotype; D010957:Plasmids; D017421:Sequence Analysis; D018909:src Homology Domains / Q000235:genetics
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D004251:DNA Transposable Elements; C087863:EaeB protein, E coli; D029968:Escherichia coli Proteins; C102051:EspA protein, E coli; D018832:Molecular Chaperones