【摘要】 <正> 1981年 Ferber Ben-Gurion 等用琼脂糖凝胶电泳证明鼠疫菌含有6、45、61Mdal 三种质粒。1982年塚野寻子等用电镜证明鼠疫菌株 Yreka 含有1、7、13、23、45Mdal 五种质粒。关于我国各自然疫源地鼠更多还原

【Abstract】 Plasmid species carried by 92 st-rains of Y.pestis isolated from va-rious natural fozi were studied by agarose gel electrophoresis.The pl-asmid associated with the produc-tion of Pasticin I is ranged from6.17 to 6.40 Mdal,the plasmidscontrolled Ca-de-pendent and viru-lent is in 43.70-46,86 Mdal andthose responsible for murein toxinenerging is in 51.64-91.80 Mdal.Itis confirmed that a few of the st-rain lost 6 or 45 Mdal p’asmids,Among the three kinds of p’asmid-s,the molecular weight of the la-rgest one from some natural foziare obviously different,so it hasthe property of classifizati on.Thestrains,from the same foci-Qinghai-Tibet plateau natural foci,thelargest plasmid carried by strainsfrom Naqu,Tibet is appeoximately92 Mdal,but that from Yushu,Qinghai and cangdu,Tibet is 63.8Mdal,that from Gonghe,Qinghaiis 52 Mdal.The strains from Qili-an and Gonghe around the Qingh-ai lake have closer relationshipwith genetice than those from Yu-shu and Naqu in view of molec-ular level,though they belong tothe different ecotypes.In addition,results of Y.pestis plasmids DNAwere also described in this paper.更多还原