Antimicrobial protein produced by pseudomonas aeruginosa JU-Ch 1, with a broad spectrum of antimicrobial activity

An antimicrobial protein, Pyocin JU-Ch 1 produced by Pseudomonas aeruginosa strain JU-Ch1, isolated from the totemic soil of a shrine that has traditionally been used as a skin ointment was purified and characterized. It exhibited broad inhibitory activity against selected, Gram positive/negative bacterial and fungal human pathogens. The Pyocin JU-Ch 1 present in the cell-free extract of producer strain was purified by salting out with ammonium sulfate, ion exchange chromatography (Diethyl aminoethyl cellulose) and hydrophobic interaction chromatography (Phenyl -Sepharose). The molecular mass of Pyocin JU-Ch 1 was estimated~30 kDa by SDS-PAGE analysis. The Pyocin JU-Ch 1 retained its activity even after incubation with different solvents, enzymes and detergents, and also was effective at a wide pH range (pH 5-pH 10) and high temperatures (40-80 °C). Various strains of Pseudomonas aeruginosa are reported to produce antimicrobial proteins that act against Gram negative, Gram positive pathogenic bacteria and yeasts. However, Pyocin JU-Ch 1reported in the present study was the first ever antimicrobial protein from Pseudomonas aeruginosa possessed antagonistic activity against multi-cellular fungal pathogens along with different Gram positive and Gram negative pathogens and therefore has the potential to develop as a broad spectrum antimicrobial drug.