title: Biogenesis of the bundle-forming pilus of enteropathogenic Escherichia coli: reconstitution of fimbriae in recombinant E. coli and role of DsbA in pilin stability--a review.
abstract: Enteropathogenic Escherichia coli (EPEC) adhere to tissue culture cells in a distinct pattern known as localized adherence (LA). We have defined two loci necessary for LA. A plasmid-encoded gene cluster encodes bundlin, the major structural subunit of a type-IV fimbria called the bundle-forming pilus (BFP), a prepilin peptidase necessary for processing of pre-bundlin to its mature form, and twelve other proteins. Under the control of an exogenous promoter, these 14 genes are sufficient for the biogenesis of BFP in a heterologous E. coli host. The chromosomal gene dsbA, which encodes a periplasmic disulfide-bond oxidoreductase, is also required for LA. In the absence of DsbA protein, bundlin is made but rapidly degraded. Pre-bundlin is also rapidly degraded in the absence of DsbA, suggesting that the prepilin is a transcytoplasmic protein simultaneously accessible to enzymes on both sides of the inner membrane. These studies offer a fresh perspective on the biogenesis of type-IV pili.
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: H Z
authors.initials: HZ
authors.lastname: Zhang
authors.forename: K D
authors.initials: KD
authors.lastname: Stone
mesh_terms: D001422:Bacterial Adhesion; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D010450:Endopeptidases; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity; D029968:Escherichia coli Proteins; D036781:Fimbriae Proteins; D010861:Fimbriae, Bacterial / Q000737:chemistry / Q000378:metabolism*; D005798:Genes, Bacterial; D007535:Isomerases / Q000235:genetics / Q000378:metabolism*; D019704:Protein Disulfide-Isomerases; D011499:Protein Processing, Post-Translational; D011994:Recombinant Proteins / Q000378:metabolism
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; C104901:BfpA protein, E coli; D029968:Escherichia coli Proteins; D011994:Recombinant Proteins; D036781:Fimbriae Proteins; D010450:Endopeptidases; C067127:prepilin peptidase protein, Bacteria; D007535:Isomerases; D019704:Protein Disulfide-Isomerases