Abstract: A L-serine producing methionine auxotroplx mutant (Met-) was derived from Pseudomonas flava LJW-01 by treatment with NTG. It could accumulate 7.5 g/L L-serine when it was cultured for 3 days by adding 1g/L Mg3(PO4)2，and it had an improvement of about 50% compared with the original strain. The mutant also had good stability of descendiblity of L-serine producing.

摘要： 以一株黄假单胞属（Pseudomonas flava）菌株LJW-01为出发菌株，经过亚硝基胍（NTG）诱变处理，选育出一株蛋氨酸营养缺陷型（Met－）菌株ZC8。研究发现，发酵33 h后向发酵液中添加1 g/L的Mg3(PO4)2，菌株的L-丝氨酸产量明显提高，并且该缺陷型菌株在35 g/L甘氨酸的条件下，发酵3 天后L-丝氨酸产量为7.5 g/L，较出发菌株提高了50%。该菌具有较好的传代稳定性。