【摘要】 对猪细小病毒(PPV)SD-68 株 vp2 基因进行的克隆和序列测定表明:SD-68 株 VP2 基因全长 1740bp,编码 579 个氨基酸残基组成的多肽;PPV SD-68 株与 Kresse 株、SY-99 株、NADL-2(5075)株、NADL-2(4973)株、US-1 株的 VP2 基因比较,核苷酸的同源性在 99%以上,氨基酸的同源性在 96%以上。进化树分析表明 SD-68株与 kresse 株的亲缘关系最近;在决定毒株组织嗜性的关键氨基酸位点上(378,383 及 436),SD-68 株与 kresse株的差异最小,据此推测 SD-68 株的组织嗜性与 Kresse 株相似,即 SD-68 株属皮炎型 PPV; 而比较弱毒株NADL-2、SD-68 和强毒株 kresse VP2 的氨基酸差异后发现,215、378 和 383 可能是决定 PPV 致病性强弱的关键位点。更多还原

【Abstract】 vp2 gene of Porcine parvovirus (PPV) SD-68 strain was cloned and sequenced .The results showed that vp2 gene of Porcine parvovirus (PPV) SD-68 strain was 1740bp and encoded a protein of 579 amino acids. vp2 gene of SD-68 strain exhibited over 99% nucleotide sequence identity and 96% amino acid sequence identity with other PPV strains: Kresse, SY-99, NADL-2(5075), NADL-2(4973), US-1. Phylogenetic tree analysis of vp2 gene showed the closest relationship between SD-68 strain and kresse strain. The difference between SD-68 strain and kresse strain was only on 378, 383 and 436 residues, which decided the tissue tropism of PPV, so the tissue tropism of SD-68 strain suggested more similar with kresse stain, that is to say, SD-68 was a dermatitis strain. Comparison of amino acid residues of virulent strain (kreese) and vaccine strain (NADL-2 and SD-68) suggested that 215, 378 and 383 were important residues that decided the pathogenicity of PPV.更多还原