鹦鹉喙羽症病毒Cap蛋白的原核表达与纯化

Prokaryotic expression and purification of capsid protein of psittacine beak and feather disease virus

鹦鹉喙羽症病毒(PBFDV)是圆环病毒科圆环病毒属的成员,可引起多个品种鹦鹉的急性死亡或者羽毛脱落和喙变形。病毒基因组中的ORF1和ORF2分别编码病毒复制相关蛋白(Rep protein)和衣壳蛋白(Cap protein)。Cap蛋白是圆环病毒的主要结构蛋白,也是其主要的免疫保护性蛋白。本试验应用PCR技术选择性扩增PBFDV Cap蛋白抗原表位集中区域的基因片段,并将其克隆入原核表达载体pGEX-6p-1中,诱导表达截短的Cap蛋白。SDS-PAGE及质谱鉴定结果显示,融合表达的CapT蛋白约45 kDa,切胶纯化后的蛋白浓度约1. 6 mg/mL。该Cap蛋白的成功获得为PBFDV治疗用阳性血清制备及亚单位疫苗的开发奠定了必要的物质基础。

Psittacine beak and feather disease virus （PBFDV） is one of the members of the genus circovirus, which cause acute death of many kinds of parrots or feather shedding and beak deformation. PBFDV ORFI and ORF2 encode the viral replication related proteins and capsid protein （ Cap protein）, respectively. Cap protein as the major structural protein of the circovirus is also the key immune protective antigen. In this study, the epitope fragment in Cap protein was amplified by PCR and then cloned into the prokary- otic expression vector pGEX - 6p - 1 to induce the truncated Cap protein expression. SDS - PAGE and mass spectrometric identifica tion showed that the MW of the obtained fusion CapT protein was about 45 kDa with a concentration about 1.6 mg/mL. This Cap pro tein provides a necessary material foundation to develop positive serum and the subunit vaccine for parrot treatment.