高产嗜热β-葡聚糖酶菌种的诱变选育研究

Study on the Mutation Breeding of High-yield Thermophilic β-glucanase Strains

以嗜热β-葡聚糖酶产生菌枯草芽孢杆菌(Bacillus subtilis XJ-Li)X-5为出发菌株,采用紫外线(UV)和硫酸二乙酯(DES)复合诱变处理技术,选育出一株产嗜热β-葡聚糖酶性能稳定、活力较高的突变株AS35。在同等摇瓶发酵条件下,其产酶活力达15.83U/mL以上,较原始出发菌株提高了81.54%。同时,经连续7次传代保存,产酶性能未出现较大的变异,表现出良好的遗传稳定性,极有潜力改良为工业化生产菌种。

A mutant strain AS-35 producing thermophilic β-glucanase with stable properties and high activities was obtained from the initial strain （Bacillus subtilis XJ-Li） X-5 by the combination treatment with UV （ultraviolet light） and DES （diethyl sulfate）. The results of the generation experiments showed that AS-35 had good genetic stability in the procedure of continual inoculation and preservation. Its enzyme activity was up to 15.83 U/mL under the same flask-shaking fermentation conditions, which had increased by 81.54 % over the original strain. It was a potential strain for thermophilic β-glueanase overproduction.