Degrading of the Pseudomonas Aeruginosa Biofilm by Extracellular Levanase SacC from Bacillus subtilis

Abstract

© 2018, Springer Science+Business Media, LLC, part of Springer Nature. Pseudomonas aeruginosa is an opportunistic pathogenic bacterium causing variety of biofilm-related infections in patients with burns, lung cancer, chronic obstructive pulmonary disease, and cystic fibrosis. Here, we show that extracellular levanase SacC from Bacillus subtilis disrupts the matrix biofilm of P. aeruginosa and this way increasing the efficacy of antibiotics against biofilm-embedded bacteria. In particular, the biofilm thickness decreased twofold after 2 h of treatment with levanase at 1 mg/ml, while 5 mg/ml of cellulase was required for the same effect. Next, in the presence of SacC, the efficacy of ciprofloxacin against biofilm-embedded P. aeruginosa increased fourfold. While the efficacy of amikacin in the presence of SacC increased fourfold against detached cell clumps, it remained unchanged against biofilm-embedded cells. These data suggest that extracellular levanase from B. subtilis could appear an alternative to other glycoside hydrolases reported to be active against biofilms of P. aeruginosa agent for external wound treatment to suppress biofilm formation and reduce reinfection risks.