This is a family of integral membrane proteins where the alignment appears to contain two duplicated modules of three transmembrane helices. The proteins are involved in the transport of anions across the cytoplasmic membrane [1] during taurine metabolism as an exporter of sulfoacetate [2]. This family used to be known as DUF81.

1: The DUF81 protein TauE in Cupriavidus necator H16, a sulfite exporter in the metabolism of C2 sulfonates. Weinitschke S, Denger K, Cook AM, Smits TH; Microbiology. 2007;153:3055-3060. PMID:17768248

2: Sulfoacetate released during the assimilation of taurine-nitrogen by Neptuniibacter caesariensis: purification of sulfoacetaldehyde dehydrogenase. Krejcik Z, Denger K, Weinitschke S, Hollemeyer K, Paces V, Cook AM, Smits TH; Arch Microbiol. 2008;190:159-168. PMID:18506422