Rhamnolipid production: effect of oxidative stress on virulence factors and proteome of Pseudomonas aeruginosa PA1.
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.
Department of Biochemistry, Chemistry Institute, Federal University of Rio de Janeiro, 21941909 Rio de Janeiro, Brazil. gjpacheco@iq.ufrj.br
Graziela Jardim
GJ
Pacheco
Rodrigo Siqueira
RS
Reis
Ana Carolina Loureiro Brito
AC
Fernandes
Surza Lucia Gonçalves
SL
da Rocha
Marcos Dias
MD
Pereira
Jonas
J
Perales
Denise Maria Guimarães
DM
Freire
D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D010450:Endopeptidases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D006017:Glycolipids / Q000096:biosynthesis*; D018384:Oxidative Stress; D010196:Pancreatic Elastase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D020543:Proteome / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011550:Pseudomonas aeruginosa / Q000737:chemistry / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D037521:Virulence Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D001426:Bacterial Proteins; D006017:Glycolipids; D020543:Proteome; D037521:Virulence Factors; C418382:rhamnolipid; D010450:Endopeptidases; D010196:Pancreatic Elastase; C087822:alkaline protease