Glutathione modulates the toxicity of, but is not a biologically relevant reductant for, the Pseudomonas aeruginosa redox toxin pyocyanin

摘要: Abstract Pyocyanin is an important redox toxin produced by the common human pathogen Pseudomonas aeruginosa. It generates reactive oxygen species (ROS) that alter intracellular status and cell function. Reducing equivalents for pyocyanin are provided NAD(P)H and, it has been reported, glutathione (GSH). Cellular GSH levels at least 1–2 orders of magnitude greater than NAD(P)H; therefore should represent major reductant potentiate its toxicity. Paradoxically, found to inhibit toxicity in cellular models. This study was undertaken evaluate potential as a biologically relevant pyocyanin. As observed using spectrophotometry, under aerobic conditions readily oxidized NADPH, whereas oxidation could not be detected. Under anaerobic reduced but reduction Reduction molecular formation ROS proceeded presence without effect. Finally, exposure normal dermal fibroblasts subcytotoxic concentrations did lead depletion endogenous GSH, exogenous protection against senescence-inducing effects toxin. In summary, does reduce physiologically or contribute However, provide deleterious this bacterial on mammalian cells.