2-heptyl-3-hydroxy-4(1H)-Quinolone (Pseudomonas Quinolone Signal) is a quorum-sensing signalling molecule produced by Pseudomonas aeruginosa in response to increased cell density. It increases the expression of the lasB gene in P. aeruginosa, the secretion of the metabolites pyocyanin and the lectin PA-IL, as well as increasing biofilm production in P. aeruginosa populations. It also reduces the iron content of the P. aeruginosa growth medium when used at a concentration of 40 μM and acts as an iron chelator in iron sulphate solutions.

2-heptyl-3-hydroxy-4(1H)-Quinolone (60 µM) 使得 P. aeruginosa 群体中的代谢产物吡咯赤藓酮和凝集素PA-IL的分泌增加，并且促进生物膜的产生。[2] 而当浓度达到40 µM时，2-heptyl-3-hydroxy-4(1H)-Quinolone 能够降低 P. aeruginosa 生长培养基中的铁水平，并且在Fe(III)-硫酸溶液中作为铁螯合剂。[3]