温氏附红细胞体部分16S rRNA基因的序列测定和分析

从确诊为附红细胞体感染的黄牛无菌采集血样，抽提附红细胞体基因组DNA，用实验设计的能扩增多种动物血营养菌部分16SrRNA基因的通用引物进行PCR扩增，结果扩增出大小约为370bp的DNA片段。PCR产物序列测定和系统进化分析显示，实验获得的核苷酸序列为温氏附红细胞体的16SrRNA基因，与国外报道的温氏附红细胞体的同源性为97％。反映出不同地理株的温氏附红细胞体存在一定的遗传差异，为牛附红细胞体病的诊断和分子流行病学研究提供科学依据。

Sequencing and phylogenetic analysis of partial 16S rRNA gene of Eperythrozoon wenyonii

The Eperythrozoon genomic DNA was extracted from blood sample with Eperythrozoon infection cattle based on the light microscopic examinations. A pair of primers HM-f and HM-r, which located in the conserved regions in 16S rRNA gene of haemotriphic bacteria, was designed and synthesized to amplify a fragment of about 370 bp from eperythrozoon 16S rR.NA gene. The PCR product sequencing and phylogenetic analysis showed that the sequence obtained from naturally infected cattle was the E. wenyonii 16S rRNA gene. It was more closely rehted to the 16S rRNA gene of E. wenyonii from cattle in United States, with a homology of 97 %.The result indicated that there were some genetic differences between different isolated strains in Eperythrozoon of cattle. These findings should have important implications for studying of molecular epidemiology and the diagnosis of eperythrozoonosis of cattle.