Development of transporter-control technology for fermentatio

嗜盐四球菌AspT催化L-天冬氨酸1-与L-丙氨酸0的电交换。动力学分析和突变分析表明，在ASPT中，L-天冬氨酸和L-丙氨酸的结合部位是独立存在的。天冬氨酸氨基转移酶跨膜3的单半胱氨酸变异表明，Tm3是L-天冬氨酸的转运途径，一些突变体失去了L-天冬氨酸的转运活性，但仍催化L-丙氨酸和L-丝氨酸的转运。

Tetragenococcus halophilus AspT catalyzes the electrogenic exchange of L-asparate1-with L-alanine0. We show that the binding sites of L-aspartate and L-alanine are independently present in AspT by means of the kinetic analyses and mutant analyses. Single-cysteine variants of transmemberane 3 of AspT revealed that TM3 was the traslocation pathway for L-aspartate and that some mutants lost L-aspatate transport activities but still catalyzed L-alanine and L-serine transport.