FIG 1.

Whole-genome phylogenetic tree of 44 MRSA strains. (A) Relationships among strains as inferred by whole-genome sequencing (phylogeny), MLVA (electrophoresis patterns), and spa typing (repeat codes). The MLVA and spa typing groups are numbered on the right. USA300 strains are indicated by a square bracket. (B) Whole-genome phylogeny for USA300 strains only. The scale bars for phylogenies in panels A and B are expressed in the number of changes per site; note the difference in scale between the two panels.