Dynamic relocalization of cytosolic type III secretion system components prevents premature protein secretion at low external pH

Abstract

Many bacterial pathogens use a type III secretion system (T3SS) to inject effector proteins into host cells. Here, Wimmi et al. show that the external pH regulates the assembly of T3SS cytosolic components in intestinal pathogens, thus preventing T3SS activity in the stomach and allowing T3SS reactivation in the intestine.