A bacterial cell-cell communication signal with cross-kingdom structural analogues

Mol Microbiol. 2004 Feb;51(3):903-12. doi: 10.1046/j.1365-2958.2003.03883.x.


Extracellular signals are the key components of microbial cell-cell communication systems. This report identified a diffusible signal factor (DSF), which regulates virulence in Xanthomonas campestris pv. campestris, as cis-11-methyl-2-dodecenoic acid, an alpha,beta unsaturated fatty acid. Analysis of DSF derivatives established the double bond at the alpha,beta positions as the most important structural feature for DSF biological activity. A range of bacterial pathogens, including several Mycobacterium species, also displayed DSF-like activity. Furthermore, DSF is structurally and functionally related to farnesoic acid (FA), which regulates morphological transition and virulence by Candida albicans, a fungal pathogen. Similar to FA, which is also an alpha,beta unsaturated fatty acid, DSF inhibits the dimorphic transition of C. albicans at a physiologically relevant concentration. We conclude that alpha,beta unsaturated fatty acids represent a new class of extracellular signals for bacterial and fungal cell-cell communications. As prokaryote-eukaryote interactions are ubiquitous, such cross-kingdom conservation in cell-cell communication systems might have significant ecological and economic importance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / chemistry
  • Bacterial Proteins / metabolism
  • Candida albicans / metabolism
  • Cell Communication / physiology*
  • Fatty Acids / chemistry
  • Fatty Acids / metabolism*
  • Molecular Structure
  • Xanthomonas campestris / metabolism
  • Xanthomonas campestris / pathogenicity*


  • Bacterial Proteins
  • Fatty Acids