阿魏酸酯酶和木聚糖酶在大肠杆菌中共表达高效制备阿魏酸

Efficient Production of Ferulic Acid by Co-expression of Feruloyl Esterase and Xylanase in Escherichia coli

摘要:

目的 实现阿魏酸酯酶（feruloyl esterases，Fae）和木聚糖酶（xylanase，Xyn）在大肠杆菌（Escherichia coli, E. coli）中的高效分泌表达。方法 从7种信号肽中筛选出适于中国荷斯坦奶牛瘤胃宏基因组来源的Fae和骆驼瘤胃宏基因组来源的β-1，4-内切木聚糖酶在大肠杆菌中分泌表达的信号肽，并构建相应的大肠杆菌工程菌，通过对发酵条件的优化实现2种酶的高效分泌表达。进一步以脱淀粉麦麸（de-starched wheat bran, DSWB）为底物发酵制备阿魏酸，确定了最佳发酵工程菌及最佳发酵条件。结果 摇瓶发酵48 h，阿魏酸产量和释放率分别达314.1 mg/L和90.0%。结论 以共表达Fae与Xyn的大肠杆菌工程菌发酵制备阿魏酸，为提高阿魏酸的快速高效生产提供了依据。

Abstract:

Objective This study aimed to develop an efficiently secretory expression system for feruloyl esterase (Fae) and xylanase (Xyn) in Escherichia coli (E. coli).Method The optimal signal peptides for the secretory expression of Fae and β-1,4-endoxylanase in E. coli were screened out from 7 signal peptides. The genes fae and xyn were from the rumen metagenomes of China Holstein cow and camel, respectively. E. coli strains expressing Fae and Xyn were constructed, and their fermentation conditions were optimized for efficient expression and secretion of the two enzymes. Furthermore, ferulic acid was prepared by fermentation with de-starched wheat bran (DSWB) as the substrate. The best performed strain and the optimal production process were then determined.Result The yield and release rate of ferulic acid reached 314.1 mg/L and 90.0%, respectively, after shake flask fermentation for 48 h.Conclusion The engineered E. coli strain co-expressing Fae and Xyn was constructed for ferulic acid production, establishing a theoretical foundation to achieve rapid and high-efficiency biosynthesis of this compound.