Figure 1. The widespread distribution of putative bacteriocin gene clusters in cyanobacteria.

The neighbor-joining tree is based on concatenated 16S and 23S rRNA genes from 55 cyanobacterial genomes. The strains which have at least one bacteriocin gene cluster are indicated with a gray background. Phylogenetic analyses were conducted in MEGA4 [41] by using the Maximum Composite Likelihood model [42] and with 50000 bootstrap replications for each branch. The bootstrap values are shown next to the branches. Outgroup taxa Gammaproteobacterium HdN1, Bradyrhizobium japonicum USDA 110, and Escherichia coli UMN026 were used to root the tree, which is drawn to scale. Strains Arthrospira PCC 8005, Leptolyngbya valderiana BDU 20041, and Prochlorococcus marinus MIT 9202 are absent from this tree because they are partial genomes and have no complete rRNA genes.