Activator for both CDC42 and RAC1 by directly engaging these Rho GTPases and acting as potent guanine nucleotide exchange factor (GEF). This activation results in actin cytoskeleton rearrangements and stimulates membrane ruffling, promoting bacterial entry into non-phagocytic cells (By similarity). Secreted via the type III secretion system 1 (SPI-1 TTSS). Encoded within a lambda-like prophage region with similarity to GIFSY phages. Belongs to the GEF (guanine exchange factor) SopE family.