Abstract

2'-Fucosyllactose (2'-FL) is one of the most important oligosaccharides in human milk. In this study, a glucose–glycerol mixed carbon source and the deletion of the genes arcA and iclR were attempted for the first time in engineered Escherichia coli to improve 2'-FL production. The highest 2'-FL titre of 5.04 g/L, almost 1.4 times higher than that in the control strain, was obtained in the arcA mutant strain using shake-flask culture. In addition, the arcA mutant showed a significantly reduced accumulation of acetate. However, the deletion of iclR and the double deletion of arcA/iclR provided no benefit in terms of 2'-FL biosynthesis. Overall, these results suggest that deletion of arcA could efficiently increase the 2'-FL yield in E. coli and could lay a foundation for more efficient and larger-scale production. Moreover, in shake-flask culture under optimal conditions, the 2'-FL titer reached a maximum value of 7.14 g/L.

摘要

2'-岩藻糖半乳糖（2'-FL）是人乳中最重要的寡糖之一。在这项研究中，首次尝试在工程化的大肠杆菌中尝试使用葡萄糖-甘油混合碳源并删除arcA和iclR基因，以提高2'-FL的产量。使用摇瓶培养法在arcA突变菌株中获得的最高2'-FL滴度为5.04 g / L，几乎是对照菌株的1.4'倍。另外，arcA突变体显示出乙酸盐的积累显着减少。但是，iclR的缺失和arcA / iclR的双重缺失在2'-FL生物合成方面没有提供益处。总体而言，这些结果表明，arcA的缺失可以有效提高大肠杆菌中2'-FL的产量，并可以为更高效，更大规模的生产奠定基础。此外，在最佳条件下的摇瓶培养中，2'-FL滴度达到最大值7.14 g / L。