Aspartate–alanine antiporter (AspT)

The **aspartate–alanine antiporter** (AspT) is a membrane transporter found in bacteria such as *Tetragenococcus halophilus*. It mediates the electrogenic exchange of L-aspartate^1−^ and L-alanine^0^ across the membrane, facilitating the uptake of aspartate in exchange for alanine as part of bacterial amino acid metabolism[1][3][5]. AspT is a secondary transport protein and belongs to the aspartate:alanine exchanger family, classified under the transporter classification (TCDB) number 2.A.81[2][4][5]. Structurally, AspT is a homodimeric protein with 10 transmembrane helices and a large cytoplasmic loop between transmembrane segments 5 and 6, containing TrkA_C and TrkA_C-like domains[1][3][7][8]. The N- and C-termini of the protein are oriented toward the periplasm. The antiporter is significant for amino acid exchange but currently is not regarded as a therapeutic target in humans, nor are there drugs directly targeting this transporter[5][7]. Its molecular action is essential in specialized bacterial metabolic pathways rather than in mammalian or clinical contexts. No notable safety concerns, biomarkers, or direct human disease associations are documented for this protein.

Other names

Aspartate-alanine transporterAspT proteinAspartate:alanine exchanger