1-Hydroxyphenazine is a phenazine pigment and virulence factor produced byP. aeruginosa.^1,2It increases production of reactive oxygen species (ROS) in RAW 264.7 cells in a concentration-dependent manner.²1-Hydroxyphenazine (≥1.55 and ≥3.12 μM) increases release of elastase and myeloperoxidase (MPO), respectively, by human neutrophils activated with N-formyl-L-methionyl-L-leucyl-L-phenylalanine and cytochalasin B .¹It reduces ciliary beat frequency in isolated guinea pig tracheal rings, resulting in ciliary dyskinesia by 1 hour when used at concentrations of 10, 50, and 100 μM and ciliary stasis by 5 hours at 50 and 100 μM.³1-Hydroxyphenazine reduces tracheal mucus velocity in anesthetized guinea pigs when administered as a 100 or 200 ng bolus dose. It is also active against the plant pathogenic fungiF. graminearum,P. grisea,A. solani,F. oxysporium, andS. sclerotiorum(MICs = 2-50 μg/ml).⁴

1.Ramafi, G., Anderson, R., Theron, A., et al.Exposure of N-formyl-L-methionyl-L-leucyl-L-phenylalanine-activated human neutrophils to the Pseudomonas aeruginosa-derived pigment 1-hydroxyphenazine is associated with impaired calcium efflux and potentiation of primary granule enzyme releaseInfect. Immun.67(10)5157-5162(1999) 2.Sinha, S., Shen, X., Gallazzi, F., et al.Generation of reactive oxygen species mediated by 1?hydroxyphenazine, a virulence factor of Pseudomonas aeruginosaChem. Res. Toxicol.28(2)175-181(2015) 3.Munro, N.C., Barker, A., Rutman, A., et al.Effect of pyocyanin and 1-hydroxyphenazine on in vivo tracheal mucus velocityJ. Appl. Physiol.67(1)316-323(1985) 4.Luo, Q., Hu, H., Peng, H., et al.Isolation and structural identification of two bioactive phenazines from Streptomyces griseoluteus P510Chin. J. Chem. Eng.23(4)699-703(2015)