目的 法呢基焦磷酸合酶(farnesyl pyrophosphate synthase,FPS)是调控黄芪甲苷生物合成途径关键酶,为该基因外源表达选择合适的宿主,进而为提高黄芪甲苷产量提供理论依据。方法 以长白山膜荚黄芪为植物材料,克隆了FPS基因的编码序列。运用EMBOSS及Codon W等在线软件分析了FPS基因的密码子偏好性,并将其与玉米、青蒿等7种植物FPS基因及大肠杆菌基因组密码子偏好性进行比较。结果 膜荚黄芪FPS基因偏好于以A或T碱基结尾的密码子,与大肠杆菌Escherichia coli基因组共有22个密码子存在差异。结论 进一步提高膜荚黄芪FPS基因在大肠杆菌中的表达水平,需对其密码子进行优化。

Objective Farnesyl pyrophosphate synthase (FPS) is the key enzyme in biosynthesis pathway of astragaloside IV. The purpose of the experiment was to provide the theory basis for selecting appropriate expression systems and regulating the content of astragaloside IV. Method FPS gene coding sequence was cloned based on Astragalus membranaceus from Changbai Mountain. Synonymous codons usage of FPS gene was analyzed by EMBOSS and Codon W programs and compared with the genome of other seven plants, such as Zea mays and Artemisia apiacea, and E. coli. Results FPS gene of A. membranaceus was bias toward the codon with A and T at the third codon position and there are 22 codons showing the significant differences between FPS gene of A. membranaceus and E. coli genome. Conclution The codons need to be optimized to improve the expression level of FPS gene in E. coli.