Rhamnolipid production: effect of oxidative stress on virulence factors and proteome of Pseudomonas aeruginosa PA1

Appl Microbiol Biotechnol. 2012 Sep;95(6):1519-29. doi: 10.1007/s00253-012-4258-y. Epub 2012 Jul 11.

Abstract

Under specific environmental conditions, Pseudomonas aeruginosa produces a biodegradable surfactant rhamnolipid. Evidences suggest that this biosurfactant is involved in protecting cells against oxidative stress; however, the effects of oxidative stress on its production and other virulence factors are still unclear. Here we show that rhamnolipid production is dependent on the aeration surface when P. aeruginosa is cultured in shaken flasks, as well as in production of elastases and alkaline proteases. The production of alginate, lipase, and pyocyanin was not detected in our shaken-flask experiments. P. aeruginosa was treated with hydrogen peroxide to trigger its oxidative stress response, and the proteome profile was analyzed. We identified 14 proteins that were expressed differently between samples that were treated and not treated with peroxide; these proteins are potentially involved in the rhamnolipid production/secretion pathway and oxidative stress.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / chemistry
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Electrophoresis, Gel, Two-Dimensional
  • Endopeptidases / chemistry
  • Endopeptidases / genetics
  • Endopeptidases / metabolism
  • Gene Expression Regulation, Bacterial
  • Glycolipids / biosynthesis*
  • Oxidative Stress*
  • Pancreatic Elastase / chemistry
  • Pancreatic Elastase / genetics
  • Pancreatic Elastase / metabolism
  • Proteome / chemistry
  • Proteome / genetics
  • Proteome / metabolism*
  • Pseudomonas aeruginosa / chemistry
  • Pseudomonas aeruginosa / enzymology
  • Pseudomonas aeruginosa / genetics
  • Pseudomonas aeruginosa / metabolism*
  • Virulence Factors / chemistry
  • Virulence Factors / genetics
  • Virulence Factors / metabolism*

Substances

  • Bacterial Proteins
  • Glycolipids
  • Proteome
  • Virulence Factors
  • rhamnolipid
  • Endopeptidases
  • Pancreatic Elastase
  • alkaline protease