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pyocyanin

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noun pyo·cy·a·nin \ ˌpī-ō-ˈsī-ə-nən \

variants: or pyocyanine play \-ˌnēn\

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

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