鼠疫耶尔森氏菌质粒提取方法的改进

The Improvement of Extracting Plasmid of ersinia pestis Strains

大多数鼠疫耶尔森氏菌均含有三种质粒，分子量分别为６５、４５和６Ｍｄａｌ。其中两种属大质粒，分离提取较困难。本实验在参照Ｃａｓｓｅ法基础上对质粒提取中诸多影响因素逐一进行测试比较，选择出质粒提取的最适条件：细菌培养于２８℃，１８～２２小时，菌液浓度为２００ｍｇ／ｍｌ，溶菌液ＳＤＳ终浓度２％，每１０ｍｌ溶菌液加０．１ＮＮａＯＨ１．３５ｍｌ，４５℃温育３０～４０分钟。建立了一种简便、快速且重复性较高的提取鼠疫菌质粒的方法。

he majority of Yersinia pestis strains has been found to carry three plasmids,with molecular weights of65 , 45 and 6MD respectively. The isolation and extraction were difficult because two out of these plasmidswere larger plasmid. In this experiment, many factors of affecting were determined in the course of plasmidextraction as described method of Casse and the most appropriate condition were chosen for plasmid ertrac-tion : bacterium were cultivated for 18～22h at 28℃, concentration of bacterium liquid were 200mg/ml, ulti-mate concentration of lysis liquid SDS were 2%,1. 35ml 0.1N NaOH was added to every 10ml Iysis Iiguid andwere incudated for 30～40 minute at 45℃. A simple,speedy and highly stable method were established for ex-tracting plasmid.