Chaperone-usher fimbriae of Escherichia coli

PLoS One. 2013;8(1):e52835. doi: 10.1371/journal.pone.0052835. Epub 2013 Jan 30.

Abstract

Chaperone-usher (CU) fimbriae are adhesive surface organelles common to many Gram-negative bacteria. Escherichia coli genomes contain a large variety of characterised and putative CU fimbrial operons, however, the classification and annotation of individual loci remains problematic. Here we describe a classification model based on usher phylogeny and genomic locus position to categorise the CU fimbrial types of E. coli. Using the BLASTp algorithm, an iterative usher protein search was performed to identify CU fimbrial operons from 35 E. coli (and one Escherichia fergusonnii) genomes representing different pathogenic and phylogenic lineages, as well as 132 Escherichia spp. plasmids. A total of 458 CU fimbrial operons were identified, which represent 38 distinct fimbrial types based on genomic locus position and usher phylogeny. The majority of fimbrial operon types occupied a specific locus position on the E. coli chromosome; exceptions were associated with mobile genetic elements. A group of core-associated E. coli CU fimbriae were defined and include the Type 1, Yad, Yeh, Yfc, Mat, F9 and Ybg fimbriae. These genes were present as intact or disrupted operons at the same genetic locus in almost all genomes examined. Evaluation of the distribution and prevalence of CU fimbrial types among different pathogenic and phylogenic groups provides an overview of group specific fimbrial profiles and insight into the ancestry and evolution of CU fimbriae in E. coli.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Escherichia coli / genetics*
  • Escherichia coli / metabolism
  • Escherichia coli Proteins / genetics*
  • Evolution, Molecular
  • Fimbriae, Bacterial / genetics
  • Fimbriae, Bacterial / metabolism*
  • Genome, Bacterial
  • Molecular Chaperones / genetics*
  • Molecular Chaperones / metabolism
  • Phylogeny

Substances

  • CfaC protein, E coli
  • Escherichia coli Proteins
  • Molecular Chaperones

Grant support

This work was supported by grants from the Australian National Health and Medical Research Council (631654 and APP1012076). MAS is the recipient of an Australian Research Council (ARC) Future Fellowship (FT100100662). SAB is the recipient of an ARC Australian Research Fellowship (DP0881247). MT is the recipient of an ARC Discovery Early Career Researcher Award(DE130101169). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.