CHARACTERISATION OF AZURIN FROM PSEUDOMONAS AERUGINOSA AND ASSESSMENT OF ITS CYTOTOXICITY

Abstract

Pseudomonas aeruginosa is a Gram-negative bacterium that is known for its virulence. The organism's exotoxins are major contributors to its virulence. This study details the characterisation and cytotoxicity of the azurin toxin purified from Pseudomonas aeruginosa isolated from the street vegetable salad sample. The band excised after the SDS-PAGE post-purification was subjected to MALDI-TOF analysis for protein identification. The excised band was approximately around 14 kDa. MALDI-TOF-based protein identification identified the protein as azurin with a score of 96, along with 59% protein sequence coverage.  The purified toxin P2 was tested for its cytotoxicity and exhibited moderate, dose-dependent anticancer activity against Caco-2 colon cancer cells, with an IC₅₀ of approximately 588 µg/mL. P2 exhibited minimal cytotoxicity towards HDF cells by maintaining more than 75% viability.