Effector proteins function to alter host cell physiology and promote bacterial survival in host tissues. This protein includes tyrosine phosphatase and GTPase activating protein (GAP) activities. After bacterial internalization, GAP mediates the reversal of the cytoskeletal changes induced by SopE. This function is independent of its tyrosine phosphatase activity, which remains unclear (By similarity). H2O + O-phospho-L-tyrosyl-[protein] = L-tyrosyl-[protein] + phosphate Forms a complex with SicP. Secreted via type III secretion system 1 (SPI-1 TTSS), and delivered into the host cytoplasm. Requires SicP as a chaperone for its stability and secretion. In the N-terminal section; belongs to the YopE family.