Effect of nitroxides on swarming motility and biofilm formation, multicellular behaviors in pseudomonas aeruginosa

César De La Fuente-Núñez, Fany Reffuveille, Kathryn E. Fairfull-Smith, Robert E.W. Hancock

Research output: Contribution to journalArticlepeer-review

50 Citations (Scopus)


The ability of nitric oxide (NO) to induce biofilm dispersion has been well established. Here, we investigated the effect of nitroxides (sterically hindered nitric oxide analogues) on biofilm formation and swarming motility in Pseudomonas aeruginosa. A transposon mutant unable to produce nitric oxide endogenously (nirS) was deficient in swarming motility relative to the wild type and the complemented strain. Moreover, expression of the nirS gene was upregulated by 9.65-fold in wild-type swarming cells compared to planktonic cells. Wild-type swarming levels were substantially restored upon the exogenous addition of nitroxide containing compounds, a finding consistent with the hypothesis that NO is necessary for swarming motility. Here, we showed that nitroxides not only mimicked the dispersal activity of NO but also prevented biofilms from forming in flow cell chambers. In addition, a nirS transposon mutant was deficient in biofilm formation relative to the wild type and the complemented strain, thus implicating NO in the formation of biofilms. Intriguingly, despite its stand-alone action in inhibiting biofilm formation and promoting dispersal, a nitroxide partially restored the ability of a nirS mutant to form biofilms.

Original languageEnglish
Pages (from-to)4877-4881
Number of pages5
JournalAntimicrobial Agents and Chemotherapy
Issue number10
Publication statusPublished - 1 Oct 2013
Externally publishedYes

ASJC Scopus subject areas

  • Pharmacology
  • Pharmacology (medical)
  • Infectious Diseases

Cite this