The Locus Encodes a Type I Toxin-Antitoxin System That Facilitates the Release of Lysogenic Sp5 Phage in Enterohemorrhagic O157.

The toxin-antitoxin (TA) genetic modules control various bacterial events, such as plasmid maintenance, persister cell formation, and phage defense. They also exist in mobile genetic elements, including prophages; however, their physiological roles remain poorly understood. Here, we demonstrate that , a putative TA locus encoded in Sakai prophage 5 (Sp5) in enterohemorrhagic O157: H7 Sakai strain, functions as a type I TA system.