pyocyanin
noun
pyo·cy·a·nin
| \ ˌpī-ō-ˈsī-ə-nən
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variants:
or pyocyanine \ -ˌnēn
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Medical Definition of pyocyanin
: a toxic blue crystalline pigment C13H10N2O that is formed in the metabolism of a bacterium of the genus Pseudomonas (P. aeruginosa), gives a bluish tint to pus infected with this organism, is a quinone imine related to phenazine, and has antibiotic activity especially toward gram-positive bacteria