Characterization of hydrogen peroxide production by Duox in bronchial epithelial cells exposed to Pseudomonas aeruginosa

National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda 20852, USA.
FEBS letters (Impact Factor: 3.17). 03/2010; 584(5):917-22. DOI: 10.1016/j.febslet.2010.01.025
Source: PubMed


Hydrogen peroxide production by the NADPH oxidase Duox1 occurs during activation of respiratory epithelial cells stimulated by purified bacterial ligands, such as lipopolysaccharide. Here, we characterize Duox activation using intact bacterial cells of several airway pathogens. We found that only Pseudomonas aeruginosa, not Burkholderia cepacia or Staphylococcus aureus, triggers H2O2 production in bronchial epithelial cells in a calcium-dependent but predominantly ATP-independent manner. Moreover, by comparing mutant Pseudomonas strains, we identify several virulence factors that participate in Duox activation, including the type-three secretion system. These data provide insight on Duox activation by mechanisms unique to P. aeruginosa.

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    • "Dual oxidases (Duox) are also expressed by epithelial cells in the airways and produce hydrogen peroxide, which contributes to antimicrobial activities through the lactoperoxidase system (Geiszt et al., 2003). This theoretically allows for partial reconstitution of ROS production in the lung in response to bacterial infection, but interesting it has been shown that Bcc does not stimulate hydrogen peroxide production by bronchial epithelial cells through Duox (Rada and Leto, 2010). "
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