Bifunctional effector protein that is secreted and delivered by the type III secretion system into eukaryotic target cells. The N-terminus encodes a GTPase-activating protein activity, whereas the C-terminus encodes an ADP-ribosyltransferase activity (PubMed:11298647). ADP-ribosylates several eukaryotic proteins including CT10 regulator of kinase (Crk) proteins (PubMed:12807879). In turn, induces atypical anoikis apoptosis by transforming Crk adaptor protein into a cytotoxin (PubMed:26020630). Affects host cell morphology by disrupting the actin cytoskeleton (PubMed:14688136). In addition to this activity, acts via its N-terminal region as a GTPase-activating protein (GAP) for host Rho GTPases including RhoA, Rac1, Cdc42 and Ras (PubMed:11895987). The GAP domain activity induces mitochondrial disruption in the target host cell by activating host caspases 3 and 9 that execute cellular death (PubMed:26451042). This activity also causes stress fiber disassembly (PubMed:11895987). L-arginyl-[protein] + NAD(+) = H(+) + N(omega)-(ADP-D-ribosyl)-L-arginyl-[protein] + nicotinamide Interacts with chaperone protein SpcS; this interaction maintains ExoT in a secretion competent state within the cytoplasm (PubMed:24387107). Interacts with host YWHAB (PubMed:30224724). Secreted via type III secretion system (T3SS) and delivered into the host cytoplasm. By host YWHAB. In the N-terminal section; belongs to the YopE family. In the C-terminal section; belongs to the Arg-specific ADP-ribosyltransferase family.