基因优化对基因工程丁型肝炎小抗原蛋白表达和纯化的影响

摘要

Objective To study the effect of gene optimization on the expression and purification of HDV small antigen produced by genetic engineering.Methods Based on the colon preference of E.coli,the HDV small antigen original gene from GenBank was optimized.Both the original gene and the optimized gene expressed in prokaryotic cells,SDS-PAGE was made to analyze the protein expression yield and to decide which protein expression style was more proportion than the other.Furthermore,two antigens were purified by chromatography in order to compare the purity by SDS-PAGE and Image Lab software.Results SDSPAGE indicated that the molecular weight of target proteins from two groups were the same as we expected.Gene optimization resulted in the higher yield and it could make the product more soluble.After chromatography,the purity of target protein from optimized gene was up to 96.3％,obviously purer than that from original gene.Conclusion Gene optimization could increase the protein expression yield and solubility of genetic engineering HDV small antigen.In addition,the product from the optimized gene group was easier to be purified for diagnosis usage.%目的 探讨基因优化对基因工程丁型肝炎(丁肝)小抗原蛋白表达和纯化的影响.方法 依据GenBank上的丁肝小抗原原始基因,参照大肠埃希菌优势密码子谱进行优化;再分别将优化前后的两组基因进行常规原核表达,用SDS-PAGE电泳比较目的蛋白表达量及优势表达方式;进一步以柱层析进行纯化,再以Image Lab软件分析SDS-PAGE电泳条带,比较两组目的蛋白的纯度.结果 SDS-PAGE显示,两组表达的目的蛋白均与预期相对分子质量大小一致,优化基因组的蛋白表达量高于原始基因组,且更倾向于可溶性表达;经柱层析纯化后,前者的目的蛋白纯度也明显高于后者,可达96.3％.结论 基因优化可提高基因工程丁肝小抗原蛋白表达量,增加可溶性蛋白的比例;且表达产物更易纯化至较高纯度以供诊断使用.