目的 :探讨寡聚组氨酸多肽与目标蛋白融合基因的表达及其产物的金属离子螯合亲和层析纯化方法。方法 :将人FLT3配体 (FL)胞外段cDNA连入 pProEXHT载体 ,转入大肠杆菌实现表达。分离包涵体并进行复性处理后 ,通过Ni2 + 离子螯合亲和层析纯化融合蛋白表达产物。结果和结论 :6×组氨酸 FL融合蛋白的表达量约占菌体蛋白总量的 15% ,用Ni2 + 离子螯合亲和层析纯化表达产物 ,一次过柱的纯度可达 90 %以上 ,操作程序简便省时 ,是日后FL基因工程产品大规模制备的可行途径 OBJECTIVE: To investigate the expression of fusion protein between oligohistidine and target protein and its purification by metal ion chelate affinity chromatography. Methods: The extracellular domain of human FLT3 ligand (FL) was inserted into pProEXHT vector and transformed into E. coli for expression. After the inclusion body was separated and renatured, the fusion protein was purified by Ni2 + ion chelate affinity chromatography. RESULTS AND CONCLUSION: The expression of 6 × histidine-FL fusion protein accounted for about 15% of the total bacterial proteins. The purified product was purified by Ni2 + ion chelate affinity chromatography. The purity of single-pass column was over 90% , The operation procedure is simple and time-saving, is the feasible way of large-scale preparation of FL gene engineering products in the future