Figure 1. Within-group genetic diversity for S. fredii, B. japonicum, is higher than the diversity within the P. syringae groups.

A rooted tree was constructed from the concatenated sequences of 103 genes present in all 17 strains and Geobacter sulfurreducens PCA and Desulfovibrio vulgaris used as outgroups. The scale bar indicates the number of amino acid substitutions per site. Phylogenetic divergence (PD) was measured for each group and compared to randomly assigned groups of strains. Reliable SNPs, based on pairwise comparisons to group-specific reference strains (*), were identified and calculated per kb (see Figure S1). The percent orthology was averaged from all within-group pairwise comparisons (see Figure S2). Each group included strains with finished (underlined) and draft genome sequences.