富铬酵母诱变及突变株筛选研究

摘要

This research mainly through three mutagenesis ways to mutagenesis of yeast,the mutagenic methods including ultraviolet irradiation,chemical mutagenesis and compound mutagenesis,and filter out high-yield strains of resistant chromium.The results showed that:through ultraviolet mutagenesis,when mutagenesis time of 100 s,the fatality rate was 80%,so100 s was the best mutation time ,and five strains(Z1,Z2,Z3,Z4,Z5)were screened;mutagenic yeast by different concentrations of DES (硫酸二乙酯),best lethal dose was the volume fraction 4%of DES,at the same time,during the process of yeast mutagenesis,five strains were isolated and screened out.When yeast compound mutation,bacteria samples treated with 4%of DES,the processing time was 25 min,and then irradiated with ultraviolet bacterial suspension 60 s,good-growing ten strains(F1,F2,F3,F4, F5,F6,F7,F8,F9,F10)were screened;screening of strains again aftering a single mutation and composite mu-tagenesis,selected chromium-rich strains F1,F2 and F6,F9,Z1,which the F9 chromium content was the high-est,reached 13.4 mg/g.%主要通过3种诱变方式对酵母进行诱变，这些诱变方式包括紫外照射、化学剂诱变和复合诱变，并筛选出高产耐铬菌株。结果表明：通过紫外诱变，当诱变时间为100 s时，致死率达到80%，所以把100 s确定为最佳诱变时间，并筛选出了5株菌株，分别命名为Z1、Z2、Z3、Z4、Z5；通过不同体积分数的DES对酵母进行诱变，最佳致死剂量是体积分数为4%的DES，与此同时，在这个酵母诱变过程当中，5株菌株被筛选分离出来；对酵母进行复合诱变时，选用4%的DES对待处理的菌样进行处理，处理时间为25 min，再利用紫外照射对菌悬液照射60 s，筛选出长得好的10只菌株，命名为F1、F2、F3、F4、F5、F6、F7、F8、F9、F10；针对上述经过单一诱变和复合诱变的菌株进行第二次筛选，选出铬含量高的菌株F1、F2、F6、F9、Z1，其中F9的铬含量最高，达到13.4 mg/g。