Pyocyanin (PCN−) is one of the many toxic compounds produced and secreted by the Gram negative bacterium Pseudomonas aeruginosa.

[6] Following this, PhzD catalyzes the hydrolytic removal the pyruvate moiety from ADIC to form (5S,6S)-6-amino-5-hydroxy-1,3-cyclohexadieve-1-carboxylic acid (DHHA).

[5] The chromosomes of most P. aeruginosa strains carry two nearly identical operons, phzA1B1C1D1E1F1G1 and phzA2B2C2D2E2F2G2, which encode the enzymes required to produce PCA.

Biosynthesis can be impaired by disrupting the aro pathway which is needed for the synthesis of chorismic acid from shikimate.

In the cystic fibrosis lung, intracellular pyocyanin converts molecular oxygen to the superoxide free radical by oxidizing NADPH to NADP+.

When the lung is confronted with pyocyanin, an increased concentration of catalase and superoxide dismutase is seen in order to deal with the barrage of radicals being produced.

Vacuolar- ATPase in yeast cells is a particularly potent target as it is the main non-mitochondrial producer of ATP but also has numerous other functions such as calcium homeostatic control, the facilitation of receptor-mediated endocytosis and the degradation of proteins.

[17] The fungicidal mechanism is the activation of NAD(P)H to induce a redox-active cascade producing reactive oxygen intermediates.

The intracellular concentration of ATP is also diminished by pyocyanin causing further damage to CFTR which are already impaired in cystic fibrosis.

Caenorhabditis elegans possesses two specific ABC transporters called pgp-1 and pgp-2 which are effectively able to extrude intracellular pyocyanin in an energy dependent manner.