MDR Escherichia coli ST-131 accesory genome evolution. Escherichia coli

Pandemic multi-drug resistant (MDR) Escherichia coli of ST131 are a major cause of bloodstream infections. Their recent global emergence seems to be due to a single MDR sub-clone, based on core genome phylogenetic analysis of human clinical isolates. Utilizing genomes of ST131 isolates from domesticated animals, wild birds, and clinical isolates we show the existence of multiple independent clones of ST131, each having undergone clonal expansion and global dissemination without habitat specificity. These data have implications for tracking and possibly preventing MDR pandemics.