The OAT protein functions as a dimer and each monomer consists of a large domain, which contributes most to subunit interface, and a C-terminal small domain, and an N-terminal region containing a helix, loop, and three-stranded beta-meander. In the central large domain is a seven-stranded beta-sheet covered by eight helices.
The OAT protein exists as a dimer, with each monomer comprising a significant structural component that facilitates subunit interaction, and a smaller terminal component. The N-terminal region features a combination of a helix, loop, and three-stranded beta-folding. In the central large domain, there is a sheet-like structure composed of seven strands, which are covered by eight helical elements.