酵母合成2'-岩藻糖基乳糖的研究进展*

2'-岩藻糖基乳糖(2'-fucosyllactose,2'-FL)是人乳寡糖中含量最高的岩藻糖基化寡糖,具有促进双歧杆菌增殖和调节肠道菌群等作用,已被广泛用于婴幼儿食品行业。目前,2'-FL已经成功在大肠杆菌、酿酒酵母、解脂耶氏酵母、枯草芽孢杆菌和谷氨酸棒杆菌中实现从头合成。考虑到食品安全、消费者认知和接受程度,酵母作为GRAS(generally recognized as safe)菌株,在2'-FL的生物合成中更具工业应用前景和商业价值。概述2'-FL的生物合成路径和现状,对2'-FL生物合成常用的底盘细胞进行比较,从底物转运、前体GDP-L-岩藻糖供应、α-1, 2-岩藻糖基转移酶、产物外排和拓宽底物谱等方面综述酵母合成2'-FL的工程化策略,提出酵母合成2'-FL的限制性因素,并对未来研究进行展望。

Research Progress of Synthesis of 2'-Fucosyllactose by Yeast

2'-Fucosyllactose is the richest fucosylated oligosaccharide in human milk oligosaccharides, which has been widely used in infant food industry due to its beneficial effect on promoting the proliferation of Bifidobacterium and regulating the balance of intestinal flora. At present, 2'-fucosyllactose has been successfully synthesized in several hosts, such as Escherichia coli, Saccharomyces cerevisiae, Yarrowia lipolytica, Bacillus subtilis and Corynebacterium glutamicum. Previous studies on the biosynthesis of 2'-fucosyllactose in Escherichia coli have been reviewed. In consideration of food safety, consumers’ cognition and acceptance, yeast, as a GRAS strain, has more industrial and commercial prospects for the biosynthesis of 2'-fucosyllactose. However, there are few reviews on the biosynthesis of 2'-fucosyllactose in yeast. Firstly, the current situation and several common hosts of biosynthesis of 2'-fucosyllactose are introduced and compared. Then, some engineering strategies of biosynthesis of 2'-fucosyllactose by yeast are introduced from five aspects, such as substrate transport, the supply of precursor GDP-L-fucose, α-1,2-fucosyltransferase, product efflux and broadening of the substrate spectrum. Finally, several limiting factors of yeast in the biosynthesis of 2'-fucosyllactose are put forward and the future development trends and prospects are discussed.