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|Section2= |Section3= }} Pyocyanin (PCN−) is one of the many toxins produced and secreted by the Gram negative bacterium ''Pseudomonas aeruginosa''. Pyocyanin is a blue, secondary metabolite with the ability to oxidise and reduce other molecules〔 〕 and therefore can kill microbes competing against ''P. aeruginosa'' as well as mammalian cells of the lungs which ''P. aeruginosa'' has infected during cystic fibrosis. Since pyocyanin is a zwitterion at blood pH, it is easily able to cross the cell membrane. There are three different states in which pyocyanin can exist; oxidized, monovalently reduced or divalently reduced. Mitochondria play a huge role in the cycling of pyocyanin between its redox states. Due to its redox-active properties, pyocyanin generates reactive oxygen species. == Synthesis == In order for pyocyanin to be synthesized by ''P. aeruginosa'', two specific genes must be functional. ''MvfR'' is a gene which produces a transcription factor which activates ''phnAB'' genes. These genes produce the molecule quinolone which then regulates operons 1 and 2 of ''phzRABCDEFG'' which are key to the synthesis of phenazine. The synthesis of pyocyanin is primarily controlled by the quorum sensing process. ''P.aeruginosa'' strains which are unable to synthesise PCN can still benefit from its effects if the strain has co- infected the lung with wild type strains which can produce pyocyanin. Biosynthesis can be impaired by disrupting the ''aro'' pathway which is responsible for the synthesis of chorismic acid from shikimate. Chorismic acid is the precursor of pyocyanin. :shikimic acid → chorismic acid → phenazine-1-carboxylic acid → 5-methylphenazine-1-carboxylic acid betaine → pyocyanin〔 〕 The complete virulence of ''P. aeruginosa'' can only be experienced when pyocyanin is produced. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「pyocyanin」の詳細全文を読む スポンサード リンク
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