中文摘要：

利用DNA重组技术，将绵羊朊病毒正常成熟蛋白基因OvPrP^C插入表达载体pET30a，在大肠杆菌BL21（DE3）中高效表达，获得的表达产物为绵羊朊蛋白OvPrP（234256），经SDS—PAGE分析，表达产物以包涵体形式存在.将包涵体蛋白用8mol／L尿素溶解，在变性条件下经Ni—NTA柱亲和层析纯化，而镍柱能竞争性结合含有6×His标签的pET30a表达的目的蛋白，由于目的蛋白是在变性条件下纯化的，需要将其复性后才能恢复天然构象、采用梯度尿素透析复性后，复性率为25％左右。为了进行重组朊蛋白的结构分析，将重组蛋白进行超滤浓缩，至蛋白浓度为0．4mg／mL时，采用远紫外线圆二色谱（CD）分析其二级结构，并对其高级结构进行了预测结果表明：通过Westem—blotting鉴定，表达的绵羊朊病毒正常成熟蛋白OvPrP（23～256）的分子量为25172．80u左右、经过Jascow32软件分析后，测得OvPrP（23-256）的二级结构含量为：α螺旋为39．4％，β折叠为0％，转角为0％，无规卷曲为60．6％。绵羊重组朊蛋白高级结构的分析为朊病毒疾病的发生机理的探讨提供科学依据．

英文摘要：

The ovine prion protein gene PRNP was expressed in E.coli. by the DNA recombination. The OvPrPc occurred in the sensitive cells （BL21） by the inclusion body, which was denatured. The inclusion body were dissolved in the urea binding buffer （8mol/L, pH 7.8 ）, and purified in the Ni-NTA agarose, which was 6 × His tagged protein. Then the target protein was recovered by dialysis, and the recovery rate was about 25 %. From the western-blotting analysis, the target protein was about 25 172.80 u. Circular dichroism spectra showed that the double minimum at 208 nm and 222 nm, which was typical feature of αhelix. The content of structure was α helix （39.4 %）, β sheet（0 %）, turn（0 %）, freedom curl（60.6 %）. It can be used for insight into the pathology of the scrapie.