Production of 3-Fucosyllactose in Engineered Escherichia coli with α-1,3-Fucosyltransferase from Helicobacter pylori

3-Fucosyllactose (3-FL), one of the major oligosaccharides in human breast milk, is produced in engineered Escherichia coli. In order to search for a good alpha-1,3-fucosyltransferase, three bacterial alpha-1,3-fucosyltransferases are expressed in engineered E. coli deficient in beta-galactosidase activity and expressing the essential enzymes for the production of guanosine 5 '-diphosphate-l-fucose, the donor of fucose for 3-FL biosynthesis. Among the three enzymes tested, the fucT gene from Helicobacter pylori National Collection of Type Cultures 11637 gives the best 3-FL production in a simple batch fermentation process using glycerol as a carbon source and lactose as an acceptor. In order to use glucose as a carbon source, the chromosomal ptsG gene, considered the main regulator of the glucose repression mechanism, is disrupted. The resulting E. coli strain of increment LP-YA+FT shows a much lower performance of 3-FL production (4.50 g L-1) than the increment L-YA+FT strain grown in a glycerol medium (10.7 g L-1), suggesting that glycerol is a better carbon source than glucose. Finally, the engineered E. coli increment LW-YA+FT expressing the essential genes for 3-FL production and blocking the colanic acid biosynthetic pathway ( increment wcaJ) exhibits the highest concentration (11.5 g L-1), yield (0.39 mol mol(-1)), and productivity (0.22 g L-1 h) of 3-FL in glycerol-limited fed-batch fermentation.