This family of domains contain a P-loop motif that is characteristic of the AAA superfamily. Many of the proteins in this family are conjugative transfer proteins. This family includes the PrrC protein that is thought to be the active component of the anticodon nuclease [1].

1: The optional E. coli prr locus encodes a latent form of phage T4-induced anticodon nuclease. Levitz R, Chapman D, Amitsur M, Green R, Snyder L, Kaufmann G; EMBO J. 1990;9:1383-1389. PMID:1691706