响应面法优化产XRN1蛋白发酵培养基

Expression of XRN1 Protein and Optimization of Fermentation Medium with Response Surface Method

应用Plackett-Burman(PB)设计法对影响XRN1蛋白表达的发酵培养基组分进行优化,选取的8个相关因子为酵母提取物、硫酸钙、MgSO4.7H2O、甘油、硫酸钾、磷酸、硫酸铵和氢氧化钾。统计分析表明,影响XRN1蛋白表达的关键因子为酵母提取物、硫酸镁和硫酸钾。在进行最陡爬坡试验逼近3个关键因素的最大响应区域的基础上,采用Box-Behnken Design法对发酵培养基组分进行优化,通过响应面法分析最佳条件为酵母提取物0.45%、硫酸镁0.38%和硫酸钾1.4%。在最佳培养条件下,工程菌生物量增加约0.5倍,蛋白表达量提高近40%。

Response surface method （RSM） was used to optimize the fermentation medium of XRN1 protein expression. The Plackett-Burman design was used to evaluate the effects of eight factors, including yeast extract, calcium sulfate, MgSO4· 7H2O, glycerol, potassium sulfate, phosphoric acid, ammonium sulfate and potassium hydroxide. The statistical analysis revealed that the key factors influencing XRN1 protein expression were yeast extract, magnesium sulfate and potassium sulfate. The path of steepest ascent was used to define optimal response region for these three factors, then the optimal level combinations of factors were obtained through Box-Behnken design, the optimal conditions were as follows： yeast extract 0.45% , magnesium sulfate 0.38% , and potassium sulfate 1.4%. Under optimal conditions, biomass of yeast could increase by 0.5 fold and expression of XRN1 protein could increase by 40%.