This domain is found in centromere-binding protein (SopB). SopB displays an intriguing range of DNA-binding properties essential for partition; it binds the centromere to form a partition complex, which recruits NTPase (SopA), and it also inhibits SopA polymerization. The domain has a helix-turn-helix (HTH) structure and is thought to be the specific DNA-binding domain mainly through residues from the recognition helix, alpha 3, of the HTH. The domain has show structural similarity to the DNA-binding domains of P1 ParB and KorB [1].

1: Insight into F plasmid DNA segregation revealed by structures of SopB and SopB-DNA complexes. Schumacher MA, Piro KM, Xu W; Nucleic Acids Res. 2010;38:4514-4526. PMID:20236989