云南省南部及东南部鼠疫菌质粒图谱分析及其流行病学意义

AN ANALYSIS OF PLASMID PROFILE AND EPIDEMIOLOGICAL SIGNIFICANCE OF YERSINIA PESTIS ISOLATED FROM THE SOUTH AND SOUTH-EAST OF YUNNAN PROVINCE

用0.7％琼脂糖凝胶电泳检查了自1996年以来云南南部及东南部所分离的41株鼠疫菌质粒DNA,结果表明来自石屏、文山、砚山、建水、个旧、禄春、开远7个县(市)的菌株质粒图谱同来自澜沧江下游的澜沧、临沧、勐海、景洪及元江流域的思茅地区的菌株一样,其中石屏分离4株缺失6Mdal质粒带型,但出现—分子量约12Mdal的清晰带型,用Pla基因作为引物,做PCR分析结果为阳性,推测可能为6Mdal质粒的二聚体。结合流行病学分析认为滇南、滇东南部分地区可能同属一片鼠疫自然疫源地。

Plasmid DNA of 41 strains of Yersinia pestis isolated from 7 counties (cities) of the south and south - east of Yunnan province from 1996 to 1997 were detected by 0.7% agrose gel electrophoresis method. The result showed that these strains were the same plasmids as strains of lower readies of the lancang river valley and Simao area of the Yuanjiang valley were. Among these strains, 4 strains isolated shipping had deletion of 6 plasmid bands. But they had an obvious plasmid bands about 12Mdal. The PCR result of 12Mdal plasmid was positive by using pla gene of Yersinia pestis as primer. It could be inferred that 12Mdal plasmid may be dipdymers of 6 Mdal plasmid. Combining with epidemiological analysis, we considered that there can be natural plague foci existing in some areas of the south and the south - east of Yunnan province.