猪生殖与呼吸综合征病毒HN/XT/07株的分离鉴定及其Nsp2基因的特性分析

从湖南湘潭某发病猪场分离到1株病毒,该病毒可使Marc-145细胞产生CPE,应用猪生殖与呼吸综合征病毒检测试剂盒从感染细胞培养物中检测到猪生殖与呼吸综合征病毒,并将该分离毒株命名为HN/XT/07。采用RT-PCR方法扩增该分离毒株的Nsp2基因,并进行序列测定,发现在2932～3031 bp之间不连续缺失了87个核苷酸。序列比对结果显示,该分离毒Nsp2基因与PRRSV经典毒株Ch-1a的核苷酸同源性为85.5%,氨基酸同源性为80.1%;与2006～2007年流行的PRRSV高致病性变异毒株NX和SD的核苷酸同源性为95.3%～96.4%,氨基酸同源性为90.9%～95.6%。

Isolation and Nsp2 genetic characterization of one strain HN/XT/07of porcine reproductive and respiratory syndrome virus

A strain of virus was isolated successfully from Xiangtan Prefecture of Hunan Province,which was able to induce Marc-145 cells to appear cytopathic effect(CPE).The isolated virus was detected in the cell cultures infected with the strain by Porcine reproductive and respiratory syndrome virus(PRRSV) Detection Kit and then designed HN/XT/07.The non structural protein gene Nsp2 was amplified by RT-PCR and sequenced.87 nucleotides were staccato deleted at sites 2932 to 3031 in Nsp2 gene.The results indicated that identity of Nsp2 gene between HN/XT/07 and classical strain Ch-1a was 85.5% in nucleotide sequence and 80.1% in amino acid sequence,and the identity of Nsp2 genes between HN/XT/07 strain and strains NX and SD which were popular with high pathogenicity in 2006 to 2007 were 95.3% to 96.4% in nucleotide sequence and 90.9%-95.6% in amino acid sequence,respectively.