Figure 4From: Phylogenetic classification of Escherichia coliO157:H7 strains of human and bovine origin using a novel set of nucleotide polymorphismsMedian-joining network of polymorphism-derived genotypes tagged with a minimal set of 32 polymorphisms. Taxonomic unit genotype numbers correspond with genotype sequences recorded in Additional data file 4 and the units are color coded by genotype for the tir 255 T>A polymorphism and host origin.Back to article page