Role of the SRRz/Rz1 lambdoid lysis cassette in the pathoadaptive evolution of Shigella
Shigella, the etiological agent of bacillary dysentery (shigellosis), is a highly adapted human pathogen. Itevolved from an innocuous ancestor resembling the Escherichia coli strain by gain and loss of genes andfunctions. While the gain process concerns the acquisition of the genetic determinants of virulence, theloss is related to the adaptation of the genome to the new pathogenic status and occurs by pathoadaptivemutation of antivirulence genes. In this study, we highlight that the SRRz/Rz1lambdoid lysis cassette, eventhough stably adopted in E.