A predicted immunity protein with an alpha+beta fold and a conserved [DE]R motif. Proteins containing this domain are present in bacterial polymorphic toxin systems as an immediate gene neighbour of the toxin gene, which usually contains toxin domains of the Ntox13 or Ntox40 families [1]. In some proteins this domain is fused to the Imm38, Pfam:PF15599 immunity domain.

1: Polymorphic toxin systems: comprehensive characterization of trafficking modes, processing, mechanisms of action, immunity and ecology using comparative genomics. Zhang D, de Souza RF, Anantharaman V, Iyer LM, Aravind L; Biol Direct. 2012;7:18. PMID:22731697