This small 70 amino acid domain is found duplicated in a family of bacterial proteins. These proteins may be DNA-binding transcription factors (Pers. comm. A Andreeva & A Murzin). It is likely, due to the similarity of fold, that this family acts as a bacterial antitoxin like the MazE antitoxin family.

1: Crystal structure of a protein associated with cell division from Mycoplasma pneumoniae (GI: 13508053): a novel fold with a conserved sequence motif. Chen S, Jancrick J, Yokota H, Kim R, Kim SH; Proteins. 2004;55:785-791. PMID:15146477