A Tale about Shigella: Evolution, Plasmid, and Virulence

Shigella spp. cause hundreds of millions intestinal infections each year. They target the mucosa human colon and are an important model intracellular bacterial pathogenesis. is a pathovar Escherichia coli that characterized by presence large invasion plasmid, pINV, which encodes characteristic type III secretion system icsA used for cytosol cell-to-cell spread, respectively. First, we review recent advances in genetic aspects Shigella, shedding light on its evolutionary history within E. lineage relationship to acquisition pINV. We then discuss insights into processes allow maintenance Finally, describe role transcription activators VirF, VirB, MxiE major virulence gene regulatory cascades control expression icsA. This provides opportunity examine interplay between these pINV-encoded transcriptional numerous chromosome-encoded factors modulate their activity. novel chromosomal genes icaR, icaT, yccE regulated MxiE. emphasizes notion have walked fine line commensalism pathogenesis much history.