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目的研究鼠疫菌基因组中3种常见质粒的基因构成和分布特征。方法应用编码基因序列相似性比对和生物信息学软件自动分析2种方法,分别对国际上已完成全基因组测序的9株鼠疫菌的鼠毒素质粒(pMT1)、低钙反应质粒(pCD1)和鼠疫菌素质粒(pPCP1)进行整体结构的比较分析。结果 pMT1质粒上存在基因大片段的重新排列,整条质粒被划分成4个主要的基因模块。CO92、KIM和91001菌株分属于东方型、中世纪型和田鼠型3个不同的生物型,他们的p MT1质粒结构各有特点;Nepal 516等其余6株菌均是古典型鼠疫菌,他们的pMT1质粒结构基本一致,且与其他3个生物型鼠疫菌株的p MT1质粒结构不同。pCD1质粒被划分成3个主要的基因模块,但整体结构在不同菌株中并无差异,只有IS100在质粒中的插入位置各不相同。pPCP1质粒上所有编码基因的排列顺序和方向在各菌株中完全相同。结论鼠疫菌pCD1和pPCP1质粒的基因结构比较稳定,而pMT1质粒结构在鼠疫菌的长期进化过程中发生了一定程度的变异。
Objective To study the gene composition and distribution characteristics of three common plasmids in Y. pestis genome. Methods Two kinds of methods were automatically analyzed by similarity of coding gene sequence and bioinformatics software. The sequences of pMT1, pCD1 and pCD1 in nine strains of Yersinia pestis isolates that had been sequenced in the world were analyzed. The plastid plasmid (pPCP1) for the overall structure of the comparative analysis. As a result, there was a rearrangement of a large gene fragment on the pMT1 plasmid, and the entire plasmid was divided into four major gene modules. CO92, KIM and 91001 strains belonged to three oriental-type and medieval-type voles and three different biotypes, and their pTT1 plasmid structure had their own characteristics. The remaining strains of Nepal 516 and so on were all classical Yersinia pestis, and their pMT1 The plasmid structure is basically the same, and with the other three strains of plague strains p MT1 plasmid structure is different. The pCD1 plasmid was divided into three major gene modules, but the overall structure did not differ among the different strains, except that IS100 was inserted at different positions in the plasmid. The sequence and orientation of all the coding genes on the pPCP1 plasmid are identical in each strain. Conclusion The genetic structure of pCD1 and pPCP1 plasmids of P. infestans is relatively stable, while the structure of pMT1 plasmid mutated to a certain extent during the long-term evolution of P. infestans.