为了解猫细小病毒（feline parvovirus，FPV）VP2蛋白的分子特点及变异规律，克隆FPV山东分离株SD-01的VP2基因，对其进行生物信息学分析。首先，以FPV阳性病料基因组DNA为模板，PCR扩增VP2基因并克隆获得重组质粒pMD18-T-FPV SD-01-VP2。测序结果显示：VP2基因全长1 755 bp，编码584个氨基酸；氨基酸同源性比对发现，与其他FPV分离株的VP2基因氨基酸同源性较高，可达99.0%~100%。生物信息学分析结果显示：VP2蛋白为非分泌型的亲水性蛋白，无信号肽和跨膜区域；二级结构中α螺旋、延伸链、β转角和无规则卷曲分别占8.7%、24.5%、4.3%和62.5%；三级结构预测发现，VP2蛋白以无规则卷曲为主，与二级结构预测结果一致。亚细胞定位预测显示，VP2蛋白不含有线粒体导肽（mTP）或分泌通道信号肽（SP），定位在细胞质和细胞核中的概率较高，分别为47.8%和26.1%。B细胞抗原表位预测结果显示，VP2蛋白的抗原性及表面可及性较高，共含有11个潜在的优势B细胞抗原表位。蛋白翻译后修饰预测结果显示，VP2蛋白可能含有49个潜在磷酸化修饰位点，6个N-糖基化修饰位点和21个O-糖基化修饰位点，且这些修饰位点在FPV VP2蛋白内高度保守。本研究有助于了解我国FPV流行情况，掌握其重要结构蛋白VP2的理化性质和特性，从而为下一步VP2蛋白功能研究和疫苗研发奠定了基础。
In order to study the molecular characteristics and variation rule of VP2 gene of feline parvovirus（FPV），the VP2 gene of Shandong strain，SD-01，was cloned to conduct bioinformatics analysis. The VP2 gene was amplified by PCR and cloned by taking genomic DNA of FPV positive lesions as a template to obtain the recombinant plasmid，pMD18-T-FPV SD-01-VP2. It was sequenced that the VP2 gene was 1 755 bp in length，encoding 584 amino acids；it was compared that it shared the highest amino acid homology with VP2 gene of other FPV strains，which could be up to 99.0% to 100%. It was found that，by bioinformatics analysis，VP2 protein was a non-secretory hydrophilic protein without a signal peptide and a transmembrane region. In the secondary structure，α-helix，extended chain，β-turn and irregular coil accounted for 8.7%，24.5%，4.3% and 62.5%，respectively；it was found that，by prediction of tertiary structure，VP2 protein was mainly irregular coil，which was consistent with the results obtained by prediction of secondary structure. It was shown that，by prediction of subcellular localization，neither a mitochondrial guide peptide（mTP）nor a secretion channel signal peptide（SP）was contained in the VP2 protein that was most likely located in cytoplasm and nucleus，accounting for 47.8% and 26.1%，respectively. It was shown that，by prediction of B-cell epitopes，VP2 protein had high antigenicity and surface accessibility，containing 11 potential dominant epitopes. And it was shown that，by prediction of post-translational modification，49 potential phosphorylation sites，6 N-glycosylation sites and 21 O-glycosylation sites were likely contained in VP2 protein，all of which were highly conserved in FPV VP2 protein. In a conclusion，the study was helpful to learn the prevalence status of FPV in China，to identify the physical and chemical properties and characteristics of its important structural protein VP2，and subsequently to lay a foundation for future study on functions of VP2 protein and development of vaccines.