Amino acid transporter with broad substrate specificity (PubMed:27281193). Can transport various amino acids, including L-threonine, L-methionine, L-lysine and L-glutamate (PubMed:27281193). L-threonine(in) = L-threonine(out) L-methionine(in) = L-methionine(out) L-lysine(in) = L-lysine(out) L-glutamate(out) = L-glutamate(in) The overall structure is basket-shaped, with a large substrate-binding cavity at the center of the molecule, and is composed of inverted structural repeats related by two-fold pseudo-symmetry. The central cavity functions as the binding site for a wide range of substrates. Belongs to the drug/metabolite transporter (DMT) superfamily. Aromatic amino acid/paraquat exporter (ArAA/P-E) (TC 2.A.7.17) family.