猪细小病毒1型(porcine parvovirus type 1,PPV1)是母猪繁殖失败的主要病原体,即通常所称的猪细小病毒.2001—2016年,在猪体相继鉴定出了6种新型猪细小病毒,分别被命名为猪细小病毒2～7型(PPV2～PPV7型).为确定中国江苏地区PPV1～PPV7型感染情况和遗传变异特征,采用PPV1～PPV7型常规PCR检测方法,从江苏地区猪场收集到2株PPV1、2株PPV2,以及PPV3、PPV4、PPV5、PPV6、PPV7各1株阳性组织病料,对这9株阳性组织病料进行全基因组测序,采用生物信息分析软件与GenBank中PPV1～PPV7型参考毒株进行比较,系统分析全基因组和衣壳蛋白2(VP2)的遗传进化分子特征.结果表明,PPV1～PPV7型测序毒株与GenBank中同型毒株全基因组同源性均高于97％,而不同型基因组间同源性均小于60.40％.PPV1～PPV7型测序毒株的VP2氨基酸序列与同型毒株同源性均高于97％,但不同型毒株之间差异巨大,PPV4与PPV5有55％同源性,其他毒株之间同源性更低,仅为9％～17％.毒力分析结果表明,2株PPV1流行株与PPV1强毒株Kresse存在相似的毒力位点,且存在5处特有的突变,可能为高毒力毒株.研究结果有助于更好地了解中国猪群中PPV1～PPV7型分子流行病学并制定科学的防治措施.
Genetic variation of complete genomes of porcine parvovirus types 1 through 7
Porcine parvovirus type 1 (PPV1),commonly known as porcine parvovirus is the main pathogen of repro-ductive disorder of sows.From 2001 to 2016,six new types of porcine parvoviruses have been identified in pigs and designated consecutively as porcine parvovirus type 2 through 7 (PPV2-PPV7 ) .In order to determine the infection status and genetic variation of PPV1-PPV7 in Jiangsu,China,two strains of PPV1,two strains of PPV2,and one strain of PPV3,PPV4,PPV5,PPV6 and PPV7 positive tissue samples were identified and collected by routine PCR assay of PPV1-PPV7 strains.These 9 complete genomes of PPV1-PPV7 were sequenced and compared with the refer-ence strains of PPV1-PPV7 in GenBank.The genetic and evolutionary molecular characteristics of PPV1-PPV7 ge-nomes and viral capsid protein 2 (VP2) were systematically analyzed by using bioinformatics analysis software.The result showed that the homology of complete genomes between PPV1-PPV7 sequencing strains and homotypic strains from GenBank was higher than 97％,while the homology between the genomes of different PPV types was less than 60.40％.The amino acid sequence of VP2 of PPV1-PPV7 sequencing strains was more than 97％ homologous to the homotypic strains from GenBank,but the homology of VP2 of different porcine parvovirus types were significantly dif-ferent.The homology of VP2 amino acid sequences between PPV4 and PPV5 was only 55％,and the homologies be-tween other PPV1-PPV7 types were even lower,ranging from 9％ to 17％.In addition,VP2 of two new PPV1 strains were analyzed for virulence.The analysis showed that two PPV1 epidemic strains had similar virulence sites with PPV1 high-virulence strain Kresse,and 5 unique mutations were found in the endemic strains,which might be high-virulence strains.This study contributes to a better understanding of the molecular epidemiology of PPV1-PPV7 in Chinese pigs and the formulation of scientific control measures.
porcine parvovirusPCR detectiongenomeviral capsid protein 2genetic variationvirulence analysis
万方数据
维普
