Dispersed cells represent a distinct stage in the transition from bacterial biofilm to planktonic lifestyles

Nat Commun. 2014 Jul 21;5:4462. doi: 10.1038/ncomms5462.

Abstract

Bacteria assume distinct lifestyles during the planktonic and biofilm modes of growth. Increased levels of the intracellular messenger c-di-GMP determine the transition from planktonic to biofilm growth, while a reduction causes biofilm dispersal. It is generally assumed that cells dispersed from biofilms immediately go into the planktonic growth phase. Here we use single-nucleotide resolution transcriptomic analysis to show that the physiology of dispersed cells from Pseudomonas aeruginosa biofilms is highly different from those of planktonic and biofilm cells. In dispersed cells, the expression of the small regulatory RNAs RsmY and RsmZ is downregulated, whereas secretion genes are induced. Dispersed cells are highly virulent against macrophages and Caenorhabditis elegans compared with planktonic cells. In addition, they are highly sensitive towards iron stress, and the combination of a biofilm-dispersing agent, an iron chelator and tobramycin efficiently reduces the survival of the dispersed cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biofilms / drug effects
  • Biofilms / growth & development
  • Caenorhabditis elegans / microbiology
  • Cells, Cultured
  • Cyclic GMP / analogs & derivatives
  • Cyclic GMP / genetics
  • Gene Expression Regulation, Bacterial
  • Iron Chelating Agents / pharmacology
  • Macrophages / microbiology
  • Mice
  • Mutation
  • Oligopeptides / metabolism
  • Pseudomonas aeruginosa / drug effects
  • Pseudomonas aeruginosa / genetics
  • Pseudomonas aeruginosa / pathogenicity*
  • Pseudomonas aeruginosa / physiology*
  • RNA, Bacterial / genetics
  • Transcriptome

Substances

  • Iron Chelating Agents
  • Oligopeptides
  • RNA, Bacterial
  • bis(3',5')-cyclic diguanylic acid
  • pyoverdin
  • Cyclic GMP

Associated data

  • SRA/SRP041868