SPI1 and infection: Also, the potential interplay of SPI1‐ and SPI2‐T3SS effectors, which are injected at distinct time points during the infection process, was only partially addressed in the early 2000s by demonstrating that the SPI1‐T3SS effector protein SipA was still present 8–12 h p.i. [206, 207], mediating the stabilization of SCV‐associated F‐actin, required for the proper localization of SifA and PipB2.