Genetic evidence that the Vibrio cholerae monolayer is a distinct stage in biofilm development

Mol Microbiol. 2004 Apr;52(2):573-87. doi: 10.1111/j.1365-2958.2004.04000.x.

Abstract

Biofilm development is conceived as a developmental process in which free swimming cells attach to a surface, first transiently and then permanently, as a single layer. This monolayer of immobilized cells gives rise to larger cell clusters that eventually develop into the biofilm, a three-dimensional structure consisting of large pillars of bacteria interspersed with water channels. Previous studies have shown that efficient development of the Vibrio cholerae biofilm requires a combination of pili, flagella and exopolysaccharide. Little is known, however, regarding the requirements for monolayer formation by wild-type V. cholerae. In this work, we have isolated the wild-type V. cholerae monolayer and demonstrated that the environmental signals, bacterial structures, and transcription profiles that induce and stabilize the monolayer state are unique. Cells in a monolayer are specialized to maintain their attachment to a surface. The surface itself activates mannose-sensitive haemagglutinin type IV pilus (MSHA)-mediated attachment, which is accompanied by repression of flagellar gene transcription. In contrast, cells in a biofilm are specialized to maintain intercellular contacts. Progression to this stage occurs when exopolysaccharide synthesis is induced by environmental monosaccharides. We propose a model for biofilm development in natural environments in which cells form a stable monolayer on a surface. As biotic surfaces are degraded with subsequent release of carbohydrates, the monolayer develops into a biofilm.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Biofilms / growth & development*
  • Culture Media
  • Fimbriae Proteins / genetics
  • Fimbriae Proteins / metabolism
  • Flagella / genetics*
  • Gene Expression Regulation, Bacterial*
  • Hemagglutinins / genetics
  • Hemagglutinins / metabolism
  • Mannose / metabolism
  • Mannose-Binding Lectin
  • Methylmannosides / metabolism
  • Methylmannosides / pharmacology
  • Movement
  • Polysaccharides, Bacterial / metabolism
  • RNA, Bacterial / analysis
  • RNA, Bacterial / isolation & purification
  • Reverse Transcriptase Polymerase Chain Reaction
  • Transcription, Genetic
  • Vibrio cholerae / genetics*
  • Vibrio cholerae / growth & development*

Substances

  • Bacterial Proteins
  • Culture Media
  • Hemagglutinins
  • Mannose-Binding Lectin
  • Methylmannosides
  • MshA protein, Vibrio cholerae
  • Polysaccharides, Bacterial
  • RNA, Bacterial
  • Fimbriae Proteins
  • methylmannoside
  • Mannose