论文部分内容阅读
目的 研究鼠疫耶尔森菌中国自然分离株 pgm位点及其侧翼序列的变异 ,了解不同疫源地菌株间的毒力差异 ,为鼠疫防治提供帮助。方法 比较分析现有 4株菌的 pgm位点及其侧翼序列的变异 ,采用PCR、等位基因特异性PCR扩增 2 6 0株中国自然分离株和 7株假结核耶尔森菌。结果 除锡林郭勒高原型和青海田鼠型菌株外 ,其他菌株均缺失了YP16 6 6的 70～ 87bp之间的 18bp碱基。 14 0 6bp处T的缺失仅存在于东方型菌株中。北天山东段型及西段A、B型 ,锡林郭勒高原型 ,青海田鼠型菌株的 pgm位点下游都没有IS10 0插入 ;锡林郭勒高原型和青海田鼠型菌株的色素沉着区有 1个IS2 85插入 ,在其下游 3kb区域还有 1个IS10 0插入。冈底斯山型和昆仑山A、B型菌株的 pgm位点上游侧翼区与其他菌株不同。36株菌的 pgm位点缺失 ,缺失的菌株主要集中在鄂尔多斯高原型 ,松辽平原B型 ,昆仑山A、B型 4种生态型菌株中。结论 北天山东段型及西段A、B型 ,锡林郭勒高原型 ,青海田鼠型菌株是中国鼠疫耶尔森菌中比较古老的菌株。锡林郭勒高原型和青海田鼠型菌株是一个独特的分支 ,建议归为第 4个生物型———田鼠型。北天山东段型及西段A、B型 ,锡林郭勒高原型 ,青海田鼠型菌株的 pgm位点 ,由于在其下游没有IS10 0插入 ,所以稳定、不易缺失?
Objective To study the variation of pgm locus and its flanking sequence of Yersinia pestis in China and understand the difference of virulence among isolates from different foci to provide help for prevention and control of plague. Methods The variation of pgm locus and its flanking sequence of four strains were compared and analyzed. PCR and allele-specific PCR were used to amplify 260 strains of Chinese natural isolates and 7 strains of Y. tuberculosis. Results All strains except for Xilingol Plateau and Qingtian Microtus ostreatus lacked 18 bp between 70 bp and 87 bp of YP16 6 6. The deletion of T at 14 0 6bp was only present in oriental strains. There was no IS10o insertion downstream of pgm sites in the eastern and northern sections of Beitian Shan, Xilin Gol plateau and Qinghai field mice, and one IS285 insertion in the pigmentation zone of Xilingol Plateau and Qinghai field mouse strains , And a further IS10o insertion in its downstream 3kb region. Gangdise and Kunlun Mountains A, B strain pgm upstream of the flanking region and other strains different. 36 strains of pgm loci were deleted, the deletion of the strains mainly concentrated in the Ordos plateau type, Songliao plain B, Kunlun Mountains A, B type four kinds of ecotype strains. Conclusion The type A and type B, type Xilin Gol plateau and the strain of Qingtiopian voles in the eastern segment of the northern Tianshan Mountains are the older strains of Yersinia pestis in China. Xilin Gol Plateau and Qingtian vole-type strain is a unique branch, it is recommended classified as the fourth biological type --- field mouse type. The pgm locus of type A and B, Xilinguole plateau and Qinghai field mouse strains in the eastern segment of the northern Tianshan Mountains are not easily deleted because there is no IS10 0 insertion downstream.