关键词: 埃希氏菌, 遗传演化关系, 进化树, 同源性, 亲缘关系, 起源地

Abstract: In order to explore the genetic evolution of Escherichia in different countries and regions, and to clarify the genetic relationship of E. in different countries and regions, bioinformatics methods were used to analyze and compare the 16S rRNA genes obtained from laboratory isolation and NCBI, and construct molecular evolutionary tree after pruning. The results showed that there was a certain genetic relationship between the strains of E. coli, which may be the relationship between ancestors and offspring, there were varying degrees of variation, and the ability of variation among different strains had different levels. The transformation ability of E. coli and E. fergusonii was the strongest, and the two strains evolved from the same original strain in a very early period. E. albertii strains coexisted in the same region with highly conservative strains, and cross-evolution existed among Asia, Oceania and Antarctica. E. marmotae and E. vulneris strains originated in the Asian continent, and E. marmotae strains from China were clustered into three groups. E. Marmota had two branches of cross evolution in China, India and South Korea. E. marmota was closely related to E. vulneris. The results provide reference for elucidating the molecular epidemiology of Escherichia.

Key words: E. coli, genetic evolution, evolutionary tree, homology, relationship, origin