摘要
用Birnbom等人的方法从大肠杆菌中提取pSDM21质粒,并通过超离心进一步纯化。以已知浓度的λDNA为标准,测定pSDM21质粒的浓度为0.3μg/μl。用纯化的pSDM21质粒转化5株常用的基因工程受体菌,其转化效率为3.8×10~3——4.1×10~4。通过比较,可以看出大肠杆菌ED8654是基因工程研究中比较理想的受体菌。
Plasmid pSDM21 from Escherichia coli was isolated by the method of Birnboim et al in this report. Further purification of the plasmid was made by ultracentrifugation. The concentration of plasmid pSDM21 was tested to be 0.3μg/μl with λDNA as standard concentration. Five common used gene engineering recipients were transformed by the purified plasmid pSDM21 at transformation effi- ciencies 3.8×l0~3——4.1×10~4. In our opinion, of the five strains tested, E. coli ED8654 is a satis- factory recipient for the study of gene engineering.
关键词
质粒
转化
大肠杆菌
基因工程
p1asmid
transformation
Escherichia coli
gene genineering