No Genotoxicity Is Detectable for Strain Nissle 1917 by Standard In Vitro and In Vivo Tests.

Probiotic strain Nissle 1917 (EcN) has a long history of safe use. However, the recently discovered presence of a locus in its genome presumably producing colibactin has questioned its safety, as colibactin has been implicated in genotoxicity. Here, we assess the genotoxic potential of EcN.