用于海水养殖水脱氮的反硝化细菌的诱变及筛选

Screening of efficient denitrobacteria induced by ultraviolet irradiation and lithium chloride

以实验室中已有的反硝化菌株作为出发菌株,对这株自然菌株进行氯化锂和紫外线照射诱变,得到2株硝酸盐还原率高且亚硝酸盐积累量低的突变体L02与Z06。在培养基中硝酸盐起始含量为1 mmol/L,静置培养的条件下,这2株突变株对硝酸盐的还原率均能达到95%以上;摇床条件下培养,其还原率也能达到94%以上,且对亚硝酸盐的积累率均为0。经过5次传代实验,L02与Z06菌株对硝酸盐的还原率始终保持在95%以上,说明其遗传性能稳定。

The denitrifying strains in our laboratory, which were used as the starting strains, were treated with ultraviolet and lithium chloride to induce mutation. Two mutants L02 and Z06 were obtained, which had high ability of nitrate reduction and low nitrite accumulation. When the two mutants were statically cultured in medium, with 1mmol/L nitrate, the nitrate reduction rates of two mutant strains reached 95%; while cultured under shaking conditions, the reduction rates were 94%, and the contents of nitrite in the medium were still 0. After five passages of experiments, the nitrate reduction rates of strains L02 and Z06 still maintained above 95%, which indicated stable genetic performance.