粒细胞埃立克体444-Epank基因的检测与序列分析

Detection and sequencial analysis of Granulocytic ehrlichia 444-Epank gene

目的 进一步证实中国大陆粒细胞埃立克体感染的病原学证据。方法 从粒细胞埃立克体结构蛋白基因序列高变区构建特异引物 ,对蜱标本、动物标本、人血标本进行聚合酶链反应(PCR)检测 ;收集全沟硬蜱特异PCR产物 ,进行克隆和序列测定 ,与GenBank中注册的序列进行同源性比较。结果 从黑龙江省采集的全沟硬蜱 (6 2组 ,310只 ) 2组中扩增出 4 4 4bp的特异DNA片段 ,而从内蒙古的动物脏器标本 (8份 )没有扩增出该片段 ,从内蒙古林业局人员血标本 (12 9份 )中扩增出1份该片段。对该片段的克隆和序列测定结果显示其DNA序列与美国人粒细胞埃立克体分离株(AF0 4 7897)对应位置相差 2 3个核苷酸 ,同源性为 94 .9% ,推测的氨基酸同源性为 88.4 4 %。结论通过粒细胞埃立克体 4 4 4

Objective To provide further pathogenic evidence of Granulocytic ehrlichia infection in China. Methods Specific primers derived from 444 Epank gene were used to amplify Granulocytic ehrlichia DNA from specimens of ticks, animals and human blood. PCR products of ticks were cloned and sequenced. Results 444 bp specific DNA fragements were amplified from 2 of 62 pools of Ixodes persulcatus collected from Heilongjiang province and 1 of 129 blood specimens from forest workers in Inner Mongolia. Eight animal specimens were negative. PCR products from ticks were then cloned and squenced. It differed at 23 positions in comparison to American strain (AF047897) with 94.9 % homology. The homology of deduced ammonia was 88.44 %. Conclusion Our findings further confirmed that Granulocytic ehrlichia infection did exist in China.