重庆流行性乙型脑炎病毒分离株CQ11-66在PrM／C及E基因区的分子特征

Molecular characterization of PrM/C and E genome of Japanese encephalitis virus isolate CQll-66 from Chongqing

目的分析重庆地区儿童流行性乙型脑炎（简称乙脑）病毒分离株CQ11-66在PrM／C及E基因区的分子特征。方法采集重庆医科大学附属儿童医院感染消化科诊断的流行性乙脑患者血液及脑脊液标本，通过接种BHK-21细胞检测并分离乙脑病毒，并对其PrM／C及E基因区测序。使用ClustalX（1．8）、MEGA5等生物学软件进行核苷酸序列、氨基酸序列及系统进化分析。结果本研究仅从儿童乙脑患者脑脊液标本中分离到1株乙脑病毒，命名为CQ11-66。CQ11-66和其他国家及地区的乙脑病毒分离株相比，PrM／C基因区总体核苷酸及氨基酸序列同源性分别为74．8％～97．4％及85．6％098．7％，而E基因区总体核苷酸及氨基酸序列同源性分别为81．6％～99．6％及94．8％～99．6％；CQ11．66株与福建省乙脑病毒人分离株相比较，在PrM／C、E基因核苷酸及氨基酸序列同源性均很高。基于PrM／C及E基因区核苷酸序列进行系统进化分析，CQ11-66株属于基因Ⅲ型。结论在重庆市儿童乙脑患者标本中分离到1株乙脑病毒CQ11-66，CQ11-66株在PrM／C和E基因区核苷酸序列和氨基酸序列同其他乙脑病毒分离株存在一定的差异，且系统进化分析显示CQ11-66株属于乙脑病毒基因Ⅲ型。

Objective To analyze the molecular characterization of PrM/C and E genome of Japanese encephalitis virus（JEV） strain, CQll-66, a newly strain isolated from patients with epidemic encephalitis B Chongqing Municipal. Methods The samples were collected from Children＇s Hospital of Chongqing Medical Umverslty, and inoculating BHK-21 cells were used to detect and isolate the Japanese encephalitis virus（JEV） strain, computer analysis of the phylogenetic, nucleic acid data and deduced amino acid sequence was accom- plished using the Clustal X（1.8） and MEGA5 programs. Results Only one JEV strain was isolated from pa- tient＇s cerebrospinal fluid specimen, named CQ11-66. Comparison of the PrM/C genome sequence of strain CQ11-66 with other 31 JEV isolates showed a 74.8%-97.4% nucleotide sequence homology among them, which resulted in 85.6%-98.7% amino acid sequence homology; Meanwhile, comparison of the E genome sequence of strain CQll-66 with other 35 JEV isolates showed a 81.6%-99.6% nucleotide sequence homology among them, which resulted in 94.8%-99.6% amino acid sequence homology. There were high homology between CQ11-65 and JEV isolates from Fujian province on nucleotide sequence and amino acid sequence. Phylogenetic analysis of PrM/C and E genome showed that the CQll-66 belonged to genotype Ⅲ. Conclusion Only one JEV strain was isolated from patient＇s cerebrospinal fluid specimen. There were some differences between CQ11- 66 strain and other JEV isolates, and CQll-66 strain belonged to genotype Ⅲ.