Role of pathogenicity islands in Salmonella during persistent infection

Abstract:

Salmonella are a major group of zoonotic foodborne pathogens. After infection, Salmonella can escape the clearance of host immune system by virtue of its unique immune escape mechanism and lurk in the host for over a year to establish persistent infection. The persistent infection of Salmonella is associated with the expression of Salmonella pathogenicity islands (SPIs), especially SPI-1 and SPI-2. SPI-1 effector proteins SipB and SipC affect bacterial invasion and induce autophagy or apoptosis in different ways. SPI-2 effector proteins SseI and SseL can assist the intracellular survival of Salmonella by regulating different signaling pathways, so as provide conditions for the persistent infection of Salmonella. This paper expounds the roles of different effector proteins such as SipB and SseL in the persistent infection of Salmonella and summarizes the effects of SPIs such as SPI-6, SPI-7, and SPI-19, hoping to provide new ideas for treating the persistent infection of Salmonella.