This family consists of bacterial domains with an Ig-like fold. Members of this family are found in bacterial and phage surface proteins such as intimins.

1: Structure of the cell-adhesion fragment of intimin from enteropathogenic Escherichia coli. Kelly G, Prasannan S, Daniell S, Fleming K, Frankel G, Dougan G, Connerton I, Matthews S; Nat Struct Biol 1999;6:313-318. PMID:10201396