Adenylyltransferase involved in virulence by mediating the addition of adenosine 5'-monophosphate (AMP) to specific threonine residue of host Rho GTPases RhoA, Rac and Cdc42. The resulting AMPylation prevents the interaction of Rho GTPases with downstream effectors, thereby inhibiting actin assembly in infected cells. ATP + L-tyrosyl-[protein] = diphosphate + O-(5'-adenylyl)-L-tyrosyl-[protein] ATP + L-threonyl-[protein] = 3-O-(5'-adenylyl)-L-threonyl-[protein] + diphosphate Translocated into the host cell via the type III secretion system (TTSS). The fido domain mediates the adenylyltransferase activity. Abolishes the ability to inhibit host Rho family GTPases and cause cytoskeletal disruption.