This domain is found at the N-terminal end of VopS from Vibrio parahaemolyticus. VopS is an adenylyltransferase involved in virulence by provoking the disruption of Rho GTPase signaling and the inhibition of actin assembly in infected cells. This domain is required for full activity of VopS. It consists of nine alpha helices [1, 2].

1: AMPylation of Rho GTPases by Vibrio VopS disrupts effector binding and downstream signaling. Yarbrough ML, Li Y, Kinch LN, Grishin NV, Ball HL, Orth K; Science. 2009;323:269-272. PMID:19039103

2: Kinetic and structural insights into the mechanism of AMPylation by VopS Fic domain. Luong P, Kinch LN, Brautigam CA, Grishin NV, Tomchick DR, Orth K; J Biol Chem. 2010;285:20155-20163. PMID:20410310