重离子诱变微生物的优良菌种的筛选.doc

摘 要 重离子诱变技术是二十世纪中后期兴起的一种新兴的诱变技术，余增亮等一些人率先把这一新兴的诱变技术应用在植物和微生物育种方面，并且取得了很大的成效。重离子诱变技术具有传线密度大，对生物体的损伤不易修复等优点，为微生物和植物诱变育种提供了一条崭新的途径。 实验菌株嗜热梭菌、酵母菌和溶纤维丁酸弧菌WH-1具有很好的纤维降解能力，并具有一定的产乙醇能力，但是嗜热梭菌、酵母菌和WH-1的乙醇产量并不是非常高，为提高乙醇产量，本课题拟通过重离子辐照诱变提高乙醇产量和产率，采用10Gy、25Gy、40Gy、60Gy、80Gy、100Gy、120Gy剂量的重离子束对嗜热梭菌进行辐照诱变，并设有0Gy空白对照研究辐照剂量与致死率的关系。 实验结果表明，重离子对菌株嗜热梭菌、酵母菌和溶纤维丁酸弧菌WH-1有明显的作用效果，随着重离子辐照剂量的增加，三株菌株的致死率明显增大，在诱变剂量为10Gy时，酵母菌菌种的致死率为零，没有发生致死效果。在诱变剂量为120Gy时，溶纤维丁酸弧菌WH-1菌种的致死率达到了100%。 关键词：诱变；重离子；致死率Abstract Heavy ion implantation technology is in the latter part of the twentieth century the rise of a new mutation technique, Yu Zengliang and others took the lead in this new mutation technique application in plant and microbial breeding, and achieved great results. The technology of heavy ion mutagenesis has the advantages of large density of transmission lines, the damage to the organism, and so on. It provides a new way for the microbial and plant mutation breeding.. Experimental strains of thermophilic clostridium thermocellum, yeast and soluble fiber butyrivibrio WH-1 has good fiber degradation ability, and has certain capability of ethanol fermentation, but addicted to ethanol production by Clostridium thermocellum, yeast and WH-1 is not very high, in order to improve the yield of ethanol. The subject intends by heavy ion irradiation mutagenesis improve ethanol yield and productivity, Gy and 25 Gy, 40 Gy, 60 Gy and 80 Gy, 100gy and 120gy dose of the heavy ion beam of Clostridium thermocellum of irradiation induced by, with Gy blank control the irradiation dose and the lethal rate. The experimental results show that the heavy ion strains of thermophilic clostridium thermocellum, yeast and soluble fiber butyrivibrio WH-1 has obvious effect, with increase of heavy ion irradiation dose, the three strains the mortality rate was significantly increased, in mutagenic dose 10 Gy, yeasts death rate is zero, no lethal effect. The lethal rate of Vibrio WH-1 strain was 100% when the mutation dose