中国鼠疫菌核糖体型地理分布

目的 了解鼠疫菌核糖体型在中国的地理分布情况。方法 用限制性内切酶对鼠疫菌染色体进行消化，电泳后，用16s-23s-5s rRNA基因探针进行Southern杂交。结果 把分离自中国不同地区的鼠疫菌共分成了三个核糖体型，每种类型的杂交图谱大概一致，区别仅在于1～2个酶切片段的有无。核糖体A型及B型较常见，分布于中国较大范围的地理区域内，C型最少，只见于某一特殊地区；核糖体型与中国鼠疫自然疫源地之间有一定的对应关系，一种疫源地对应一种核糖体型常见。结论 核糖体型在中国鼠疫自然疫源地内比较稳定，不同核糖体型在中国的分布具有明显的地域性；A、B、C三种核糖体型具有不同的来源，而A型与C型的亲缘关系更近。

The geographical distribution of ribotypes of Yersiniapestis in China

OBJECTIVE: To type and group the Yersinia pestis strains isolated in China to clarify the geographical distribution of ribotypes of Yersinia pestis. METHODS: Genomic DNA of Yersinia pestis were digested with EcoR I, then hybridized with 16s-23s-5s rRNA gene probe. RESULTS: These tested strains were divided into 3 ribotypes, the profiles obtained were relatively homogeneous, with most of them differed only by the presence or the absence of 1 - 2 restriction fragments. Ribotype A and B were the most common types, which distributed in a large area in China while ribotype C was the least, only limited to a small area. There was certain correlation between the ribotypes and the plague foci, usually only one ribotype was found in one plague foci. CONCLUSION: The ribotypes were stable in the plague foci. Correlation between the ribotypes of Yersinia pestis strains and their geographical origins was noticed. All 3 ribotypes had different origins, however ribotype A and ribotype C seemed to be closer related.