Alternate thermoregulation and functional binding of Escherichia coli type 1 fimbriae in environmental and animal isolates

Jacqueline Marshall, Yannick Rossez, Geoffrey Mainda, David L. Gally, Tim J. Daniell, Nicola J. Holden*

*Corresponding author for this work

Research output: Contribution to journalLetter

3 Citations (Scopus)

Abstract

Type 1 fimbriae (T1F) are well characterised cell surface organelles expressed by Escherichia coli and required for adherence to mannosylated host tissue. They satisfy molecular Koch's postulates as a virulence determinant and a host-adapted role has been reinforced by reports that T1F expression is repressed at submammalian temperatures. Analysis of a group of 136 environmental and animal E. coli isolates that express T1F at 37°C showed that 28% are also capable of expression at 20°C, in a phase variable manner. The heterogeneous proportions varied widely, and although growth temperature impacted the total proportion expressing T1F, there was no direct correlation between growth at 37°C and 20°C, indicative of differences in thermoregulation of the genetic switch (fimS) that controls phase variation. Specificities of the adhesin (FimH) also varied between the isolates: most bound to α-(1-3) mannan and yeast extracts as expected, but some recognised β-(1-4)-mannans and N-linked glycoproteins from plants, and T1F from two of the isolates mediated binding to plant roots. The results expand our view of a well-described adherence factor to show alternative expression profiles and adhesin specificities, which in turn may confer an advantage for certain isolates in alternative hosts and habitats.

Original languageEnglish
Article numberfnw251
JournalFEMS Microbiology Letters
Volume363
Issue number22
Early online date2 Nov 2016
DOIs
Publication statusPrint publication - Nov 2016
Externally publishedYes

Keywords

  • Adhesin
  • Animals
  • Mannosides
  • Pili
  • Plants
  • T-RLFP

Fingerprint Dive into the research topics of 'Alternate thermoregulation and functional binding of Escherichia coli type 1 fimbriae in environmental and animal isolates'. Together they form a unique fingerprint.

  • Cite this