Pyocyanin is the blue phenazine pigment produced by Pseudomonas aeruginosa. Pyocyanin production using immobilized cells was investigated. The maximum production of pyocyanin was obtained using cells immobilized in kappa-carrageenan. Moreover, 0.01% PO4(3-), 0.2% Mg(2+), 0.001% Fe(2+), 1% glycerine, 0.8% leucine and 0.8% dl-alanine were also essential for pyocyanin production. Pyocyanin was pur...

The production of pyocyanin from the opportunistic pathogen Pseudomonas aeruginosa was probed using a variety of miniaturized electrochemical systems. Goal 1 used disposable screen printed carbon electrodes to measure pyocyanin in medically relevant samples showing for the first time that pyocyanin can be detected at medically relevant concentrations (1-100 µM) without sample processing. Goal 2...

Five different isolates of Pseudomonas aeruginosa were obtained from surgical specimens and minced meat. The isolates were tested for the production of the blue pigment; pyocyanin. Considerable amounts of blue pigment were produced by P. aeruginosa isolates when grown on the four tested media. Müller-Hinton agar was further used for growth, pigment production and sensitivity tests. Pigment prod...

Clearance of neutrophils from inflamed sites is critical for resolution of inflammation, but pathogen-driven neutrophil apoptosis can impair host defenses. We previously showed that pyocyanin, a phenazine toxic metabolite produced by Pseudomonas aeruginosa, accelerates neutrophil apoptosis in vitro. We compared wild-type and pyocyanin-deficient strains of P. aeruginosa in a murine model of acut...

The aim of this study was to examine the effects of pyocyanin exposure on mitochondrial GSH, other cellular thiols (thioredoxin-1, Trx-1), and oxidant-sensitive signaling pathways hypoxia inducible factor (HIF-1α) and heme oxygenase (HO-1) in A549 and HBE cell lines. A549 human type II alveolar epithelial cells and human bronchial epithelial (HBE) cells were treated with varying concentrations ...

Bacterial adhesion and biofilm formation are both dependent on the production of extracellular polymeric substances (EPS) mainly composed of polysaccharides, proteins, lipids, and extracellular DNA (eDNA). eDNA promotes biofilm establishment in a wide range of bacterial species. In Pseudomonas aeruginosa eDNA is major component of biofilms and is essential for biofilm formation and stability. I...

Pseudomonas aeruginosa, an opportunistic human pathogen, causes acute pneumonia in patients with hospital-acquired infections and is commonly associated with chronic lung disease in individuals with cystic fibrosis (CF). Evidence suggests that the pathophysiological effects of P. aeruginosa are mediated in part by virulence factors secreted by the bacterium. Among these factors is pyocyanin, a ...

Silver in its ionic form (Ag+), but not the bulk metal (Ag0), is toxic to microbial life forms and has been used for many years in the treatment of wound infections. The prevalence of bacterial resistance to silver is considered low due to the nonspecific nature of its toxicity. However, the recent increased use of silver as an antimicrobial agent for medical, consumer, and industrial products ...

Pseudomonas aeruginosa produces copious amounts of the redoxactive tricyclic compound pyocyanin that kills competing microbes and mammalian cells, especially during cystic fibrosis lung infection. Cross-phylum susceptibility to pyocyanin suggests the existence of evolutionarily conserved physiological targets. We screened a Saccharomyces cerevisiae deletion library to identify presumptive pyocy...

Alpha1 Protease inhibitor (alpha1PI) modulates serine protease activity in the lung. Reactive oxygen species inactivate alpha1PI, and this process has been implicated in the pathogenesis of a variety of forms of lung injury. An imbalance of protease-antiprotease activity is also detected in the airways of patients with cystic fibrosis-associated lung disease who are infected with Pseudomonas ae...