Epigenetic acquisition of inducibility of type III cytotoxicity in P. aeruginosa

Background: Pseudomonas aeruginosa, an opportunistic pathogen, is often encountered in chronic lung diseases such as cystic fibrosis or chronic obstructive pneumonia, as well as acute settings like mechanical ventilation acquired pneumonia or neutropenic patients. It is a major cause of mortality and morbidity in these diseases. In lungs, P. aeruginosa settles in a biofilm mode of growth with the secretion of exopolysaccharides in which it is encapsulated, enhancing its antibiotic resistance and contributing to the respiratory deficiency of patients. However, bacteria must first multiply to a high density and display a cytotoxic phenotype to avoid the host's defences. A virulence determinant implicated in this step of infection is the type III secretion system (TTSS), allowing toxin injection directly into host cells. At the beginning of the infection, most strains isolated from patients' lungs possess an inducible TTSS allowing toxins injection or secretion upon in vivo or ...

• Type: Journal
• Year: 2006
• Where: BMCBI
• Authors: Didier Filopon, Annabelle Mérieau, Gilles Bernot, Jean-Paul Comet, Rozenne LeBerre, Benoit Guery, Benoit Polack, Janine Guespin-Michel
• Keywords: BMCBI 2006, Chronic Obstructive Pneumonia, Epigenetic Hypothesis, TTSS