Phylogenetic relationships of Y. pseudotuberculosis. (A) Neighbor-joining tree of the 62 STs. STs that form CCs are shown with the CC number followed by the members of the CC in parentheses. The founder of the CC is highlighted in boldface. On the right of the tree are shown the presence and absence of the three virulence factors, the HPI, YPM, and pYV; the number of isolates in each ST; and the source and location of isolation. The sources are h (human), w (water), and a (animal). The locations are AU (Australia), BE (Belgium), CA (Canada), CN (China), DK (Denmark), FR (France), IT (Italy), JP (Japan), KR (South Korea), RU (Russia), UK (England), and US (United States). Y. enterocolitica strain 8081f was used as the outgroup. Bootstrap values greater than 50% are shown at the nodes of the neighbor-joining trees. The name of each cluster is indicated at the right brace. (B) Neighbor net network of the 61 STs, excluding ST20.