FimH adhesin of type 1 pili is assembled into a fibrillar tip structure in the Enterobacteriaceae.

Published

Journal Article

Type 1 pili are heteropolymeric mannosebinding fibers produced by all members of the Enterobacteriaceae family. The bulk of the fiber is composed of FimA. Two macromolecular complexes responsible for mediating an interaction with mannose-containing receptors were purified from fimA- Escherichia coli by mannose affinity chromatography and ion-exchange chromatography. One complex contained only the mannose-binding adhesin, FimH, associated with FimG, a minor component of the type 1 pilus. In the other complex the FimG-FimH moiety was loosely associated with a chaperone-minor subunit complex (FimC-FimF), possibly representing an intermediate in tip fibrilla assembly. The FimC chaperone has also been shown to form a preassembly complex with FimH that has been purified and characterized previously. Purified FimC did not bind to the FimG-FimH complex but did recognize FimH dissociated from the FimG-FimH complex. Quick-freeze deep-etch electron microscopy revealed that the FimG-FimH complex had a thin fibrillar architecture. High-resolution electron microscopy of type 1 pili revealed that a 16-nm fibrillar tip structure with an architecture identical to that of the FimG-FimH complex was joined end-to-end to the pilus rod. In a fimH- deletion mutant, the tip fibrillae joined to pilus rods were approximately 3 nm in length. The full-length tip fibrilla was restored by complementation with the fimH gene in trans. The bipartite nature of the type 1 pilus was also demonstrated on pili purified from clinical isolates of members of the Enterobacteriaceae family arguing that it is a conserved feature of the type 1 pilus.

Full Text

Duke Authors

Cited Authors

  • Jones, CH; Pinkner, JS; Roth, R; Heuser, J; Nicholes, AV; Abraham, SN; Hultgren, SJ

Published Date

  • March 14, 1995

Published In

Volume / Issue

  • 92 / 6

Start / End Page

  • 2081 - 2085

PubMed ID

  • 7892228

Pubmed Central ID

  • 7892228

International Standard Serial Number (ISSN)

  • 0027-8424

Digital Object Identifier (DOI)

  • 10.1073/pnas.92.6.2081

Language

  • eng

Conference Location

  • United States