Interestingly, S. Typhimurium lacks the TviA regulator, which implied the existence of a different pathway in non-typhoidal serovars of Salmonella. The SsrB-mediated repression of the SPI-1 and flagellar genes in S. Typhimurium might be important in order to limit pyroptosis and apoptosis following infection by this serotype. This evidence concerns the gene SPI1 and infection.