Figure 1.

Unrooted maximum-likelihood phylogenetic tree of partial cyanobactin N-terminal protease (A) gene sequences (819 bp). The six clusters are identified by I–VI. Numbers along branches indicate the percentage of bootstrap support considering 1000 pseudo-replicates: only those equal to or higher than 70% are indicated. Strains from this study are indicated in light blue, whereas strains producing known cyanobactins are shaded with different colors. Strain Oscillatoria sp. PCC 6506 contains the cyanobactin osc gene cluster but its product remains unknown (see text for details). Cyanobactin gene cluster from strain Microcystis aeruginosa NIES-843 is inactive [14]. Strains marked with an asterisk correspond to isolates with A-genes identified through antiSmash searches, not previously described in the literature.