Fig. 5: Convergent evolution of biofilm formation capacity.

a Capacity to form surface-attached biofilms on silicone-coated pegs with or without fibrinogen coating, distributed according to phylogeny among isolates. Bars indicate means (n = 4 biological replicates with 95% CI) of total crystal violet (CV)-stained biomass of 48 h biofilms. Isolates where only one biological replicate showed an increase were not considered as these were likely spontaneous mutants that can be rapidly selected in this clone. Comparison to the index was done by one-way ANOVA followed by Dunnett’s T3 multiple comparison; two-tailed p-values are shown. Highlighted genetic changes are most likely responsible for the increased biofilm phenotype based on nearest-neighbour comparisons. Genes with at least 2 independent mutations associated with biofilm increase are highlighted. b Biofilm evolution scenarios with consecutive genetic changes leading to increased or decreased biofilm formation. Means of four biological replicates with 95% CI are shown. Comparisons of DA25130 and DA25128 to DA25127 were done by one-way ANOVA with Dunnett’s T3 post hoc, and DA25060 was compared to DA25061 by an unpaired t-test with Welch’s correction; two-tailed p-values exceeding significance (<0.05) are shown. c Interconnection between acute virulence and survival in serum among isolates with increased biofilm formation capacity on silicone with fibrinogen. Blue dots indicate isolates with wzc missense mutations. Pearson correlation coefficient (r) with 95% CI and a two-tailed p-value is shown. Source data are provided as a Source Data file.