1. Phylogenetic tree of Shigella, EIEC, and nonpathogenic E
Phylogenetic tree of Shigella, EIEC, and nonpathogenic E. coli strains, showing the evolutionary relationship between 32 EIEC strains, 46 Shigella strains, and 20 E. coli reference strains of the ECOR group (EcoR strains) based on comparison of selected housekeeping gene sequences.
Phylogenetic tree of Shigella, EIEC, and nonpathogenic E. coli strains, showing the evolutionary relationship between 32 EIEC strains, 46 Shigella strains, and 20 E. coli reference strains of the ECOR group (EcoR strains) based on comparison of selected housekeeping gene sequences. Shigella groups in 3 phylogenetic clusters (C1 to C3) and EIEC in 4 phylogenetic clusters (C4 to C7), with broad distribution of traditionally surface antigen profile-classified strains. EIEC and Shigella strains outside clusters C1 to C7 are depicted in bold. Both EIEC and Shigella arose several times from multiple ancestral origins. The EIEC strain in C2 is assumed to be misclassified. The number of strains in a cluster is shown in parentheses. The Salmonella LT2 strain serves as outgroup. (Adapted from reference 409 with permission.)‏
Matthew A. Croxen et al. Clin. Microbiol. Rev. 2013; doi: /CMR