金黄色葡萄球菌CCC型及OC型质粒的检测

Detection of Staphylococcal Plasmids Involving CCC and OC Forms

采用已报道的金黄色葡萄球菌质粒DNA的检测方法(简称LL法)。从1982年在南京地区临床分离的131株金黄色葡萄球菌中的125株(95.4%)中检出质粒,可分为21质粒谱。经单向及双向二步琼脂糖凝胶电泳法鉴别,按分子量共有16个CCC型质粒带(P_1～P_(16))。用改良的LL法制备E.coli V517菌株质粒DNA,建立了简便的测定金黄色葡萄球菌质粒DNA分子量的参考系统。结果表明:要本实验条件下,P_1～P_(16)的分子量为1.42 Md～22.24±0.73 Md;以含有14.88、2.66±0.06 Md质粒谱的菌株较常见,占总数的25.2%;2.66±0.06 Md的质粒最常见,在73.3%的菌株中检出。

Studies showed that 125 of the total 131 strains of Staphylococcus aureus isolated in Nanjing contained plasmid DNA, in which 74.8% of the strains demonstrated at least two plasmid DNA bands in the profiles by the LL method. Two-step agarose gel electrophoresis was employed to detect the CCC and OC plasmid DNA bands. Molecular weights of the CCC plasmid DNA bands were estimated by comparison with those of reference plasmids extracteed from E. coli V517 using the LL method with modification. Twenty-one plasmid profiles in the strains of Staphylococus aureus were found, in which there were 16 CCC plasmid DNA bands ranging from 1.42 Md to 22.24+0.73 Md. The 2.66+0.06 Md plasmid DNA was detected from 73.3% of the strains. Strains containing 14.88 and 2.66+0.06 Md plasmids were the most encountered (25.2%).