Role of type 1 fimbriae and mannose in the development of Escherichia coli K12 biofilm: from initial cell adhesion to biofilm formation

Biofouling. 2009;25(5):401-11. doi: 10.1080/08927010902833443.


The influence of type 1 fimbriae, mannose-sensitive structures, on biofilm development and maturation has been examined by the use of three isogenic Escherichia coli K12 strains: wild type, fimbriated, and non-fimbriated. Experiments with the three strains were done in minimal medium or Luria-Bertani broth supplemented with different concentrations of d-mannose. The investigation consisted of: (1) characterizing the bacterial surface of the three strains with respect to hydrophilicity and surface charge, (2) investigating the effect of type 1 fimbriae on bacterial adhesion rate and reversibility of initial adhesion on glass surfaces, and (3) verifying the role of type 1 fimbriae and exopolysaccharides (EPS) in biofilm maturation. The results suggest that type 1 fimbriae are not required for the initial bacterial adhesion on glass surfaces as the non-fimbriated cells had higher adhesion rates and irreversible deposition. Type 1 fimbriae, however, are critical for subsequent biofilm development. It was hypothesized that in the biofilm maturation step, the cells synthesize mannose-rich EPS, which functions as a 'conditioning film' that can be recognized by the type 1 fimbriae.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Adhesion / drug effects*
  • Biofilms / drug effects
  • Biofilms / growth & development*
  • Escherichia coli K12 / drug effects
  • Escherichia coli K12 / growth & development*
  • Escherichia coli K12 / metabolism
  • Glass
  • Mannose / metabolism
  • Mannose / pharmacology*
  • Receptors, Immunologic / genetics
  • Receptors, Immunologic / metabolism
  • Receptors, Immunologic / physiology*


  • Receptors, Immunologic
  • fimbriae receptor, type 1
  • Mannose