Pyocyanine (85-66-5), a redox-active phenazine produced by P. aeruginosa and other pathogens, is an electron receptor, which stimulates redox cycling in bacteria as well as in a variety of human cell lines. It enhances oxidative metabolism, which increases the formation of intracellular reactive oxygen species (ROS) via reduction of NADPH. Pyocyanine accelerates neutrophil apoptosis in vitro. Pyocyanine production by P. aeruginosa suppresses the acute inflammatory response by pathogen-driven acceleration of neutrophil apoptosis and associated reduction of local inflammation.
1) Rada and Leto (2013), Pyocyanin effects on respiratory epithelium: relevance in Pseudomonas Aeruginosa airway infections; Trends Microbiol., 21 73
2) Reszka et al. (2012), Inactivation of the potent Pseudomonas aeruginosa cytotoxin pyocyanin by airway peroxidases and nitrite; Am. J. Physiol. Lung Cell Mol. Physiol., 302 L1044