从中哈边境亚洲璃眼蜱中检测到弗朗西斯氏菌样内共生体核酸

First detection of Francisella-like endosymbionts in Hyalomma asiaticum asiaticum from China-Kazakhstan border

目的对中哈边境铁路线区域的亚洲璃眼蜱中弗朗西斯菌属及内共生体检测。方法 2015年在中哈边境采集的游离蜱进行形态学与分子学鉴定后,扩增弗朗西斯菌属及共生体16SrRNA和sdhA基因,对阳性产物测序后进行Blast分析,用Mega 6.0构建分子遗传进化树。结果对243只游离蜱经形态学与分子学鉴定为亚洲璃眼蜱后,经PCR病原学检测及测序得到35份(只)阳性,阳性率为14.4%。分析得到两株(Seq1和Seq2)不同基因型的序列,遗传进化树显示,这两株弗朗西斯菌属内共生体聚到1支,未检测到土拉弗朗西斯菌。结论在中哈边境铁路线区域亚洲璃眼蜱中首次检测到弗朗西斯菌样核酸。

We conducted the detection the Francisellaspp.nucle acid from Hyalomma asiaticum asiaticum that main distribution is on railway line area from China-Kazakhstan border.The free-living ticks were collected and then identified by morphological and molecular methods.After species identification,they were detected by PCR targeting 16 SrRNA and sdhA of Francisellaspp.The amplified products were sequenced and the sequences was analyzed by using the Blast.A phylogenetic tree was constructed using MEGA 6software.A total of 243 fleas were identified as H.asiaticum asiaticum.Only 35 samples were detected for Francisellaspp.positive and the positive rate was 14.4%.Sequence analysis showed that two different sequences（seq1and seq2）and all belong to Francisella-like endosymbionts（FLEs）.Phylogenetic analyses showed that two FLEs were belong to the same cladd.This is first detection of FLEs nucleic acid from H.asiaticum Railway line area of China-Kazakhstan border.