为了探讨猪细小病毒(Porcine parvovirus，PPV)不同毒株致病性差异的原因，利用生物信息学在线软件比较PPV NADL-2株和Kresse株的非结构蛋白NS1的氨基酸位点差异，并利用一系列在线软件比较两者的氨基酸理化性质、亲水/疏水性、跨膜区、信号肽的异同，进一步分析两者的结构域、二级结构、三级结构的异同。结果表明，2种毒株在621—636位的氨基酸存在较大差异，Kresse株的疏水性较弱，且二级结构中Kresse株含较多的卷曲结构。经过三级结构比对，并结合以上结果推测,2种毒株致病性差异是由于621—636位未知功能的结构域不同所致。

In order to explore the cause of the difference in the pathogenicity of the different strains of porcine parvovirus (PPV), the amino acid site differences of the non-structural protein NS1 of PPV NADL-2 and Kresse strains were compared by using bioinformatics online softwares,and a series of online softwares were used to compare the differences of physicochemical property,hydrophobicity/hydrophilicity and signal peptide between them,and then analyze their domain,secondary structure and tertiary structure.The result showed that there were significant differences in amino acids at 621—636 sites between the two strains.The hydrophobicity of Kresse strain was weak,and in the secondary structure it contained more curly structures. Through the comparison of the tertiary structures combining the above results,it was inferred that the difference in pathogenicity between the two strains was due to the different domains of unknown functions at 621—636 sites.