De novo biosynthesis of 2′-fucosyllactose by bioengineered Corynebacterium glutamicum

2'-Fucosyllactose (2'-FL) which is well-known human milk oligosaccharide was biotechnologically synthesized using engineered Corynebacterium glutamicum, a GRAS microbial workhorse. By construction of the complete de novo pathway for GDP-Lfucose supply and heterologous expression of Escherichia coli lactose permease and Helicobacter pylori alpha-1,2-fucosyltransferase, bioengineered C. glutamicum BCGW_TL successfully biosynthesized 0.25 g L-1 2'-FL from glucose. The additional genetic perturbations including the expression of a putative 2'-FL exporter and disruption of the chromosomal pfkA gene allowed C. glutamicum BCGW_cTTLE Delta P to produce 2.5 g L-1 2'-FL batchwise. Finally, optimized fed-batch cultivation of the BCGW_cTTLE.P using glucose, fructose, and lactose resulted in 21.5 g L-1 2'-FL production with a productivity of 0.12 g L-1.h, which were more than 3.3 times higher value relative to the batch culture of the BCGW_TL. Conclusively, it would be a groundwork to adopt C. glutamicum for biotechnological production of other food additives including human milk oligosaccharides.

Automated summary

2'-Fucosyllactose (2'-FL), a human milk oligosaccharide, was successfully synthesized using engineered Corynebacterium glutamicum. The optimized fed-batch cultivation strategy significantly increased the production and productivity of 2'-FL.