【摘要】 从以鸡腺胃肿大为致病特征的病例中鉴定了一株新的禽传染性支气管炎病毒变异毒株 (命名为传染性支气管炎病毒嗜腺胃毒株 ,ZJ971株 ) ,对该毒株进行 RT- PCR扩增 ,将得到的 S基因 c DNA克隆入 p Bluescript SK(+)质粒载体中。测序结果显示 ,传染性支气管炎病毒嗜腺胃毒株 ZJ971株 S基因全长为 3492 nt,编码一条 10 80个氨基酸组成的多肽 ,其核苷酸与已报道 IBV- Beaudette、M4 1、Ark99、Cut2毒株比较 ,同源性分别为 97.3%、97.5 %、88.6 %、85 .6 % ;氨基酸的同源性分别为 96 %、96 .3%、86 .1%、83.1%。ZJ971毒株 S基因第 32 4 1位的碱基由 G突变为 T,造成 S蛋白的翻译从 3492位核苷酸提前到 32 4 0位终止更多还原

【Abstract】 A novel proventriculopathogic variant(isolate ZJ971) of infectious bronchitis virus was identified from enlarged proventriculus of the sick chickens in the study. The S gene cDNA segment with 3.6 kb in length was amplified by RT PCR with special primers from the ZJ971 viral strain of infectious bronchitis virus(IBV) and cloned into plasmid pBluescript SK(+). The recombinants contained S gene of IBV ZJ971 strain were identified by digestion of restriction enzyme EcoRⅠ, BamHⅠ and PCR amplification. The cloned S gene from IBV ZJ971 strain was composed of 3492 bp in length encoding for a polypeptide of 1080 amino acids.Compared with that of reported IBV strains Beaudette, M41, Ark99 and Cut2, the nucleotide homogeneity of S gene of IBV ZJ971 strain was 97 3%,97 5%,88 6% and 85 6%, respectively;and the homogeneity of the deduced amino acids of S protein of IBV ZJ971 was 96%, 96 3%, 86 1% and 83 1% respectively; Especially, the mutation of 3241st nucleotide of S gene of IBV ZJ971 strain from G to T resulted in the translating termination of S protein at 3240th nucleotide site.更多还原