Fig. 2.

(a) Phylogenetic tree of 14 C. difficile genomes constructed using SNP data. Branches corresponding to partitions reproduced in less than 50% of replicate bootstrap determinations are collapsed. The percentages of replicate trees in which the associated taxa clustered together in the bootstrap test (100 replicates) are shown next to the branches. Genomes cluster into 3 distinct groups: NAP1 isolates (red), NAP7-NAP8 isolates (blue), and the 3 remaining isolates (black [R group]). (b) Numbers of polymorphic SNPs observed for the three groups (large boxes), as well as variations observed between isolates within each group (remaining values). SNPs (text at center bottom) that uniquely identify the members of each group are also indicated.