Whole cell biosynthesis of a functional oligosaccharide, 2'-fucosyllactose, using engineered Escherichia coli.
Whole cell biosynthesis of a functional oligosaccharide, 2'-fucosyllactose, using engineered Escherichia coli.
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使用工程性大肠杆菌，功能性寡糖，2'-五核酸的全细胞生物合成。
DOI：
10.1186/1475-2859-11-48
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发表时间：
2012-04-30
影响因子：
6.4
通讯作者：
Seo JH
中科院分区：
文献类型：
--
作者：
Lee WH;Pathanibul P;Quarterman J;Jo JH;Han NS;Miller MJ;Jin YS;Seo JH
2‘-岩藻糖基乳糖(2-FL)是一种存在于母乳中的功能性低聚糖，可抵抗肠道病原体的感染。由于乳糖在α-1，2-岩藻糖基转移酶(FucT2)的作用下可与鸟苷-2‘-二磷酸-L-岩藻糖发生岩藻糖基化反应而合成2-FL，因此可通过过量表达内源GDP-L岩藻糖生物合成酶和外源岩藻糖基转移酶基因构建产生2-FL的大肠杆菌。将幽门螺杆菌FucT2基因导入表达载体pGDP-L-岩藻糖重组菌BL21STAR(DE3)。然而，由于大肠杆菌BL21star(DE3)菌株吸收乳糖而不是转化为2-FL，所以在分批发酵中只能产生少量的2-FL。选择不能同化乳糖的大肠杆菌JM109(DE3)作为2-FL产生菌。用不同浓度的乳糖进行了一系列分批发酵，研究了乳糖全细胞生物合成2-FL的过程。分批发酵结果表明，工程菌JM109(DE3)能缓慢吸收乳糖，在不添加生长辅助糖的情况下合成2-FL。分批发酵最高2-FL浓度为1.23 g/L，乳糖浓度为14.5 g/L。实验得到的产率(g2-FL/g乳糖)相当于基元通量模式(EFM)估计的理论最大产率的20%。本研究的实验2-FL产量相当于理论最高产量的20%左右，这表明可以通过对宿主菌株的代谢工程或发酵工艺的优化来进一步改良以提高2-FL产量。利用工程菌提高乳糖生产2-FL的微生物产量，将增加2-FL作为益生素在各种食品中应用的可行性。
2'-Fucosyllactose (2-FL) is a functional oligosaccharide present in human milk which protects against the infection of enteric pathogens. Because 2-FL can be synthesized through the enzymatic fucosylation of lactose with guanosine 5′-diphosphate (GDP)-l-fucose by α-1,2-fucosyltransferase (FucT2), an 2-FL producing Escherichia coli can be constructed through overexpressing genes coding for endogenous GDP- l-fucose biosynthetic enzymes and heterologous fucosyltransferase. The gene for FucT2 from Helicobacter pylori was introduced to the GDP- l-fucose producing recombinant E. coli BL21 star(DE3) strain. However, only small amount of 2-FL was produced in a batch fermentation because the E. coli BL21star(DE3) strain assimilated lactose instead of converting to 2-FL. As an alternative host, the E. coli JM109(DE3) strain which is incapable of assimilating lactose was chosen as a 2-FL producer. Whole cell biosynthesis of 2-FL from lactose was investigated in a series of batch fermentations using various concentrations of lactose. The results of batch fermentations showed that lactose was slowly assimilated by the engineered E. coli JM109(DE3) strain and 2-FL was synthesized without supplementation of another auxiliary sugar for cell growth. A maximum 2-FL concentration of 1.23 g/l was obtained from a batch fermentation with 14.5 g/l lactose. The experimentally obtained yield (g 2-FL/g lactose) corresponded to 20% of the theoretical maximum yield estimated by the elementary flux mode (EFM) analysis. The experimental 2-FL yield in this study corresponded to about 20% of the theoretical maximum yield, which suggests further modifications via metabolic engineering of a host strain or optimization of fermentation processes might be carried out for improving 2-FL yield. Improvement of microbial production of 2-FL from lactose by engineered E. coli would increase the feasibility of utilizing 2-FL as a prebiotic in various foods.
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影响因子：
5
作者：
Byun, Seong-Goo;Kim, Myoung-Dong;Seo, Jin-Ho
通讯作者：
Seo, Jin-Ho
影响因子：
3.6
作者：
Chessa D;Winter MG;Jakomin M;Bäumler AJ
通讯作者：
Bäumler AJ
影响因子：
5
作者：
Trinh CT;Wlaschin A;Srienc F
通讯作者：
Srienc F
影响因子：
46.9
作者：
Schuster, S;Fell, DA;Dandekar, T
通讯作者：
Dandekar, T
影响因子：
5.8
作者：
Pfeiffer, T;Sánchez-Valdenebro, I;Schuster, S
通讯作者：
Schuster, S