中文摘要：

目的利用人Nm23-H1基因原核表达载体,在大肠杆菌中表达并纯化融合蛋白,并对蛋白其活性进行初步分析。方法将重组质粒pET28a-Nm23-H1转化入E.coliBL21（DE3）,IPTG诱导表达并鉴定。用金属螯合层析技术进行蛋白纯化,得到Nm23-H1融合蛋白,用SDS-PAGE及Western blot鉴定纯化蛋白,并用RP-HPLC法、电泳迁移率变动分析实验检测Nm23-H1融合蛋白的核苷二磷酸激酶（NDPK）活性及核酸内切酶（AP）修复活性。结果转化溶原菌后能够表达目的蛋白,蛋白表达量高,为可溶性蛋白。Ni2＋柱纯化后得到Nm23-H1融合蛋白经SDS-PAGE及Western blot鉴定正确。RP-HPLC法就及电泳迁移率变动分析实验证明所纯化的Nm23-H1融合蛋白具有NDPK活性,不具有AP修复活性,但可以增加APE1蛋白的AP修复活性。结论利用原核表达载体pET28a-Nm23-H1在E.coliBL21（DE3）中高效表达和纯化得到具有NDPK活性,但无AP修复活性的Nm23-H1融合蛋白,此蛋白可以增强APE1蛋白的AP修复活性,共同参与细胞的DNA损伤修复。

英文摘要：

Objective To construct the prokaryotic expression vector for human Nm23-H1 genes and purify its fusion protein and study its activity. Methods Recombinant plasmid pET28a-Nm23-H1 was transformed into E.coli BL21 （DE3） and its expression was induced and identified with IPTG. The expressed Nm23-H1 fusion protein was purified by affinity chromatographic with Ni2＋ column and identified by SDS-PAGE and Western blotting. Immunogenicity and activity of Nm23-H1 fusion protein were analyzed by RP-HPLC and EMSA. Results The prokaryotic expression vector of pET28a-Nm23-H1 could express the Nm23-H1 fusion protein in E.coli BL21 （DE3）. The Nm23-H1 fusion protein with NDPK activity could be purified by affinity chromatographic with Ni2＋ column. However,the AP endonuclease activity of Nm23-H1 protein was too weak to be detected. Conclusion Nm23-H1 fusion protein is highly expressed in E.coli BL21 （DE3） and can be purified,which is of great significance for elucidating the biologic characteristics of Nm23-H1 genes.