肌苷产生菌抗低浓度8-氮鸟嘌呤突变株选育

BREEDING OF THE MUTANTS RESISTANT TO A LOW CONCENTRATION OF 8-AZAGUANINE FROM INOSINE PRODUCTION STRAIN BACILLUS SUBTILIS

以枯草芽孢杆菌SM－12－2为出发菌株，经物理、化学诱变剂连续处理，获得一株缺失AMP脱氨酶活性的突变株A－308。再对该突变株进行选育，获得一株抗低浓度8－氮鸟嘌呤突变株No．164。该突变株肌苷产量较亲株有明显提高，发酵周期缩短，菌落形态也有很大差别，摇瓶发酵肌苷产量18．75g／L。

A inosine producing strain Bacillus subtilis SM-12-2 were mutated by U V-ray、EMS and NTG repeatedly, then a strain Bacillus subtilis A-308 lacking AMP deaminase activity were obtained. The mutant strain No. 164 resistant to a low concentration of 8-azaguanine were obtained by the EMS treatment of strain A-308. The inosine accumulation by strain NO. 164 was markedly higher than that by the parents. and its fermentation time was de creased. The colony shape of strain NO. 164 was markedly different from that of the par ents. The strain NO. 164 accumulated 18.75g/kuter of inosine in shake culture.