CopG antitoxin is a member of a type II toxin-antitoxin system family found in bacteria and archaea. Most antitoxins encoded by the relBE and parDE loci belong to the MetJ/Arc/CopG family of dimeric proteins which bind DNA through N-terminal ribbon-helix-helix (RHH) motifs [1]. The toxin for CopG proteins falls into the family BrnT_toxin, Pfam:PF04365.

1: Prokaryotic toxin-antitoxin stress response loci. Gerdes K, Christensen SK, Lobner-Olesen A; Nat Rev Microbiol. 2005;3:371-382. PMID:15864262