FIG 3.

Molecular-clock estimates in the emergence of ST772. Shown is a phylogenetic time tree with the timescale estimated in Least Squares Dating (LSD). The annotations for nodes represent the time of origin (in years) of basal strains and subgroups A1, A2, A3, including 95% confidence intervals (CIs) and the most recent common ancestor (MRCA) of ST772. Tips are colored according to the subgroup, and the position of the root was optimized during the analysis. Arrows indicate acquisition of three critical mobile genetic elements: the PVL/sea-prophage φ-IND772, an integrated multidrug resistance plasmid, and the short staphylococcal cassette chromosome SCCmec-V (5C2).