Original strain, Corynebacterium glutamicum AS1542, was mutanted by DES and UV. protoplast irradiation. Finally, a higher L-tryptophan producing strain,T11-6 was obtained. It was a double auxotroph of phenylalanine and tyrosine.

• 以谷氨酸棒杆菌AS1542为出发菌株，经过硫酸二乙酯诱变和紫外原生质体诱变，定向选育出一株稳定的色氨酸生产菌T11－6，该菌株具有苯丙氨酸、酪氨酸双重营养缺陷及对氟苯丙氨酸、5-甲基色氨酸、6-氟色氨酸三种结构类似物抗性遗传标记。