The Trypanosoma Archaic Translocase of the Outer Membrane (T-ATOM) system in hydrogenosome TOM complexes may have arisen from TOM complexes of the Mitochondrial Protein Translocase (MPT) Family (TC# 3.A.8), and therefore, some of the members of both families may be homologous.  The proteins of the T-ATOM family include:

1. ATOM40 (TOM40-like), PWV02635.1), a porin of 350 aas in Trypanosoma cruzi. A homolog is listed under TC# 1.B.8.8.5.
2. Small Hsp20 of 142 aas (AXL08036.1) of T. cruzi.
3. ATOM69 (TOM70-like), (618 aas, AXL07972.1) of T. cruzi
4. ATOM46 (TOM20-like), 412 aas, PWV00646.1) of T. cruzi
Other protein constituents may also be present in this complex.