用平截末端使大豆根瘤菌苹果酸脱氨酶基因插入失活及电激法转化

Insertional Inactivation or the Malate Dehydro genase Gene from Bradyrhizobium japonicum by Blunt Ends and Transformation by Electroporation

本实验用平截末端连接法把卡那霉素抗性基因插入到大豆根瘤菌（Ｂｒａｈｙｒｈ；ｚｏｂｉｕｍｊａｐｏｎｉｃｕｍ）１１０的苹果酸脱氢酶（ｍｄｈ）基因中，致使ｍｄｈ基因失活，再通过电激法把这一重组基因转入大豆根瘤菌（Ｂｒａｈｙｒｈｉｚｏｂｉｕｍｊａｐｏｎｉｃｕｍ）２１４３中，进而探讨ｍｄｈ基因失活对大豆固氮作用的影响。

The objective was to mser a kanamycin resistance gene into the gene for malate dehydro genase (mdh) from Bradgrhizobium japonicum 110. First, the mdh gene was cut with the restriction enzyme Sea Ⅰ. Then a kanamycin resistance gene (Pharmacia) sold as a Ecor Ⅰ Fragment of DNA was repared with Klenow to generate blunt ends. The kanamycin resistance gene was ligated into the middle of gene for mdh. Insertion of kanamycin cassette inactivates mdh gene. The recombinant DNA was transferred into B. japonicum 2143 by electroporation to test the effect of an inactive mdh gene on nittegen fixation by soybean.