Figure 1. Phylogenetic Distribution of the Curli Systems and Operon Structure.

Taxonomic analysis was performed based on the NCBI taxonomy and visualized using MEGAN [49]. The number of strains containing curli systems within each genus is indicated next to the taxonomic units. Note that these numbers are highly influenced by the number of sequenced strains within each phylogenetic group and therefore do not reflect the prevalence of curli systems within these groups. Genera highlighted in red represent genera where curli systems have been previously described. Organization of the curli operons is illustrated for each genus.