Multifunctional virulence effector protein DrrA (Defects in Rab1 recruitment protein A) [Includes: Protein adenylyltransferase (AMPylator) (EC 2.7.7.108) (Protein guanylyltransferase) (GMPylator) (EC 2.7.7.n6); Rab1 guanine nucleotide exchange factor]