【摘要】 从上海市发病鸡群中分离到两株新城疫病毒(NDV),其MDT分别为51.2 h和50.4 h,ICPI分别为1.850和1.875,均为强毒株。用RT-PCR扩增F基因cDNA片段,并将其分别克隆到pGEM-T easy载体中。序列分析结果表明,两分离株的F基因片段均为1654 bp,编码551个氨基酸,其F蛋白的氨基酸序列同源性达100%,但与常见疫苗株的氨基酸同源性仅为78.3%~83.7%。F蛋白裂解位点序列均为112R-R-Q-K-R-F117,属于基因Ⅶ型NDV。更多还原

【Abstract】 Two strains of Newcastle disease virus(NDV) were isolated from infected chicken flocks in Shanghai.They were determined as virulent strains whose MDT was 51.2 h and 50.4 h,and ICPI was 1.850 and 1.875,respectively.The cDNA fragments of F gene of the 2 NDV strains were amplified by RT-PCR and then cloned into pGEM-T easy vector.The sequence analysis showed that the F gene fragments from the 2 NDV isolates consisted of l 654 bp,coding for 551 amino acids.The amino acid sequence homology between the 2 NDV isolates came to 100%,but that between the 2 isolates and common NDV vaccine strains(La Sota,B1,F48E9 and V4) was only 78.3%~83.7%.The sequence of cleavage site of F protein was 112R-R-Q-K-R-F117,belonging to the genotype Ⅶ of NDV.更多还原