Fig 3.

Phylogeny of the emm28 strains based on SNPs. An unrooted maximum-likelihood tree including the five emm28.8 strains and the reference strain MGAS6180 was constructed using the 172 core SNPs out of the 186 total SNPs identified compared to the sequence of MGAS6180, which were obtained by excluding 14 SNPs associated with recombination events, as described in the supplemental material. Numbers on internal nodes represent the percentage of replicated trees (>50%) in which the associated samples clustered together in the bootstrap test (based on 1,000 replicates). The scale bar represents the number of base substitutions per site.