analysis of antibacterial and antibiofilm activity of purified recombinant azurin from pseudomonas aeruginosa

Background and objectives: the aim of this study was to evaluate the antibacterial and antibiofilm activity of recombinant azurin from pseudomonas aeruginosa against different bacterial species. materials and methods: the azurin gene was cloned in the pet21a vector. the pet21a-azurin construct was transformed into escherichia coli bl21. the recombinant azurin was expressed and purified using affinity chromatography and con- firmed by western blotting. the cytotoxicity of razurin was assessed on peripheral blood mononuclear cells. antibacterial and antibiofilm activity of razurin with different concentrations were determined by micro-broth dilution and crystal violet methods, respectively. the effect of razurin on bacterial species was statistically analyzed by t- test and spearman correlation. results: the identity of purified protein was confirmed by blotting and distinguished as a 14 kda band on 15% sds-page. the ic50 of razurin on peripheral blood mononuclear cell (pbmc) was determined as 377.91±0.5 μg/ml in 24 h. vibrio cholerae and campilobacter jejuni displayed the most sensitivity to razurin (27.5 and 55 μg/ml, respectively) and the highest resistance (220 μg/ml) was displayed by p. aeruginosa and e. coli. the mic for other species was 110 μg/ml. the minimum biofilm inhibition concentration (mbic) was determined as 220 μg/ml for salmonella enterica and v. cholerae, 300 μg/ml for shigella sonnei, shigella flexneri and p. aeruginosa and 440 μg/ml for the other species. the antimicrobial effect of razurin on bacterial species were significant (p value<0.05) and correlation coefficient was negative. conclusion: the razurin appears to be an appropriate choice and a new strategy for prevention of bacterial infection. it inhibits bacterial growth and biofilm formation and candidates as antimicrobial peptides.