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, including VirB4 components of the Type IV secretory pathway and conjugal transfer protein TrbE. This entry includes the arcaheal Vir4/HerA homologue CedB [2], a membrane-bound protein that is highly induced upon UV treatment and essential for DNA transfer between Sulfolobus cells [2].

1: The VirB4 family of proposed traffic nucleoside triphosphatases: common motifs in plasmid RP4 TrbE are essential for conjugation and phage adsorption. Rabel C, Grahn AM, Lurz R, Lanka E; J Bacteriol. 2003;185:1045-1058. PMID:12533481

2: The archaeal Ced system imports DNA. van Wolferen M, Wagner A, van der Does C, Albers SV; Proc Natl Acad Sci U S A. 2016;113:2496-2501. PMID:26884154