Members of this family are putative integral membrane proteins from bacteria. Several of the members are mycobacterial proteins. Many of the proteins contain two copies of this aligned region. The function of these proteins is not known, although it has been suggested that they may be involved in lipid transport [1].

1: Analysis of the proteome of Mycobacterium tuberculosis in silico. Tekaia F, Gordon SV, Garnier T, Brosch R, Barrell BG, Cole ST; Tuber Lung Dis 1999;79:329-342. PMID:10694977