Figure 1.

Growth rate (A), biofilm formation (B) and protease activity (C) of A. xylosoxidans isolates. Growth rate was calculated from 24 h growth curves in LB medium (A). Adhesion was measured by crystal violet staining of surface-attached bacteria divided by A₆₀₀ of non-attached bacteria (B). Protease activity was measured in culture supernatant by azocasein assay. Protease activity is expressed as enzymatic units per ml (C). Each value represents the mean ± SEM of three experiments. Statistical analysis was performed by t test, ** p < 0.01.