Marin M S, McKenzie J, Gao G F, Reid H W, Antoniadis A, Gould E A
Institute of Virology and Environmental Microbiology, Edinburgh.
Res Vet Sci. 1995 Jan;58(1):11-3. doi: 10.1016/0034-5288(95)90081-0.
The nucleotide and deduced primary amino acid sequence of the envelope gene of two virus isolates from the brains of Spanish sheep with encephalomyelitis, were determined and compared with those of other flaviviruses. The amino acid alignments showed that the Spanish viruses shared 95 to 96 per cent homology with the envelope protein of louping ill virus and western European tick-borne encephalitis virus. In comparison, the maximum variation in amino acid identities among strains of louping ill virus from the British Isles is 1.8 per cent. The Spanish isolates were distinguishable from all other known flaviviruses by the presence of a unique tripeptide sequence (AQR) at amino acid positions 232 to 234 in the E protein, the position at which a genetic marker for distinct flavivirus species has been identified. Other genetic markers, viz DSGHD (amino acids 320 to 324) and EHLPTA (amino acids 207 to 212), which identify the tick-borne encephalitis group within the genus Flavivirus, were present in the amino acid sequences of the Spanish virus. It is concluded that the cause of sheep encephalomyelitis in Spain is a distinct species in the tick-borne encephalitis virus group.
测定了从患有脑脊髓炎的西班牙绵羊脑中分离出的两种病毒株包膜基因的核苷酸序列和推导的一级氨基酸序列，并与其他黄病毒的序列进行了比较。氨基酸比对显示，西班牙病毒与跳跃病病毒和西欧蜱传脑炎病毒的包膜蛋白具有95%至96%的同源性。相比之下，来自不列颠群岛的跳跃病病毒株之间氨基酸同一性的最大差异为1.8%。西班牙分离株与所有其他已知黄病毒的区别在于，其E蛋白氨基酸位置232至234处存在独特的三肽序列（AQR），该位置已被确定为不同黄病毒种类的遗传标记。其他遗传标记，即识别黄病毒属内蜱传脑炎病毒组的DSGHD（氨基酸320至324）和EHLPTA（氨基酸207至212），也存在于西班牙病毒的氨基酸序列中。得出的结论是，西班牙绵羊脑脊髓炎的病因是蜱传脑炎病毒组中的一个独特物种。
