离子束诱变中Bacillus fordii MH602菌体保护剂的研究

离子束诱变过程中，菌体细胞较长时间处于干燥、营养贫瘠的条件下，死亡率高,本研究比较了在干燥、营养贫瘠条件下，多种寡糖对对数生长期的嗜热海因酶产生菌Bacillus fordii MH602菌体细胞的保护作用．海藻糖效果显著，其最佳保护剂量为2％；同时证明海藻糖的保护作用没有对离子注入效应产生负面影响；首次报道了在离子束诱变技术中采用海藻糖作为保护剂提高突变率和诱变效果．相关结论对于抗干燥性能较差的微生物采用离子束诱变技术进行菌种选育具有实际指导作用．

Study on Protectors for Bacillus fordii MH602 in the Ion Beam Mutation

During the ion beam mutation process, microbes have to be put under a dry condition without nutrient for a long time, thus results in a high death rate of the cells. Bacillus fordii MH602 can produce thermostable hydantoinase. Very low survival rate is obtained when MH602 is treated with ion beam in the exponential growth phase. In order to protect the cells under the dry condition, the effects of several oligosaccharides on the cells of MH602 are determined. The best protector is trehalose with the optimal concentration of 2%. Negative effects from ion beam mutation of trehalose are not found. This is the first report that trehalose can be used as a protector to improve the mutation rate and effects from the ion beam mutation. These results can help the strains used to have poor ability to resist dry conditions in the ion beam mutation.