云南省泸西县鼠类斑点热立克次体基因检测分析

Detection of spotted fever group Rickettsia Gene in mice in Luxi County, Yunnan

目的了解云南省泸西县鼠形动物携带斑点热立克次体的状况及其分子生物学特征,为斑点热疾病的预防控制提供科学依据。方法采用鼠笼和鼠夹在云南省泸西县居民区和野外捕鼠,捕获的鼠进行分类鉴定并剖取脾脏。采用巢式PCR检测鼠脾脏中斑点热立克次体groEL基因,阳性标本进行序列测定,通过美国国家生物技术信息中心网站对基因序列进行BLAST比较,构建系统进化树进行同源性及进化分析。结果在泸西县共捕获鼠193只。其中居民区64只,以黄胸鼠为优势鼠种;野外129只,以大绒鼠和中华姬鼠为优势鼠种。鼠脾脏巢式PCR扩增,从野外大绒鼠中检测到1株groEL基因阳性标本(LX68),阳性率为0.52%。该阳性片段测序后在GenBANK库中经BLAST比较分析,与Rickettsia raoultii、Rickettsia rickettsii和Rickettsia sibirica相似性较高。系统进化树分析表明,该片段与斑点热劳氏立克次体株(GenBank:KJ41028850)、立氏立克次体株(GenBank:U96733)和西伯利亚立克次体株(GenBank:AY059014)在同一分支,同源关系非常近。结论该地区大绒鼠中存在斑点热立克次体感染。

Objective To understand the status and molecular biological characteristics of the spotted fever group rickettsis(SFGR)in the mouse in Luxi County Yunnan Province,and we provide the scientific basis for the prevention and control of the diseases.Methods This investigation selected the samples from Luxi County.Using rat-cage and rattrap to catch mouse in residential areas and wild areas of Luxi County.The captured animals were classified,identified and their spleen was cut off.groEL gene of SFGR in spleen of mice were detected by Nest PCR.The positive sample was sequenced.The gene sequences were compared by BLAST on the US National Center for Biotechnology Information web.The homology of the SFGR were analyzed according to phylogenetic tree.Results A total of 193 rats were captured in Luxi county.Among them,64 were in residential area,with Rattus flavipectus as the dominant species;129 rats in the wild field were captured,with Eothenomys miletusas and Apodemus draca as dominant species.The spleen of mice was detected by nest PCR,one groEL positive sample of SFGR(LX68)was detected by nested PCR in field Eothenomys miletusas mice,and positive rate was 0.52%.The positive sample was sequenced and analyzed by BLAST in genebank library.The similarity with Rickettsia raoultii,Rickettsia rickettsii and Rickettsia sibirica was high.The results of phylogenetic tree showed that this fragment was in the same branch with the Rickettsia raoultiis train(Genbank:KJ410288),Rickettsia rickettsii(GenBank:U96733)and Rickettsia sibirica(GenBank:AY059014),and homologous relationship was very close.Conclusion The Eothenomys miletus in this region were infected with spotted fever group rickettsis.