Resistance of biofilms containing alginate-producing bacteria to disintegration by an alginate degrading enzyme (algl)

Abstract

Pure culture biofilms of Pseudomonas aeruginosa (strains 8830 and ATCC 700829) and mixed population biofilms composed of Pseudomonas aeruginosa (ATCC 700829), Pseudomonas fluorescens (ATCC 700830), and Klebsiella pneumoniae (ATCC 700831) were treated with an alginate-degrading enzyme (AlgL). The enzyme effectively depolymerized the mannuronic acid rich (92%), partially O-acetylated bacterial alginate produced by P. aeruginosa (8830), both in dilute solution and in a gel-like, concentrated state. However, both biofilms were unaffected by the presence of the enzyme. These findings suggest either that bacterial alginates do not contribute significantly to the cohesiveness of biofilms or that the alginate is protected from enzymatic degradation in Biofilms.