用高产菌株制备T_4—DNA连接酶

PREPARATION OF T_4-DNA LIGASE FROM HIGR YIELD BACTERIAL STRAIN

DNA连接酶是遗传工程研究工作中必不可少的工具酶,常用的有两类即大肠杆菌DNA连接酶及T4-DNA连接酶。其中T4-DNA连接酶不仅具有连接带有粘末端DNA片段的能力,而且还具有连接平末端DNA片段的能力,因而T4-DNA连接酶比大肠杆菌DNA连接酶的用途更大。

T_4-DNA ligase is an important enzyme in DNA-recombination technique. We described a simple method for preparing T_4-DNA ligase from a high yield NM989 lysogenic strain in this paper. It consists of the following steps: ammonium sulfate precipitation, P11-cellulose fractionation,DE AE-cellulose fraction ation and HAP chromatography. The materials are easy to obtain, require unique buffer system and only one step chromatography, these make the method very convenient and time saving. The enzyme obtained by this method is very satisfactory.