当前位置: X-MOL 学术Biotechnol. Bioeng. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Improved succinate production from galactose-rich feedstocks by engineered Escherichia coli under anaerobic conditions.
Biotechnology and Bioengineering ( IF 3.5 ) Pub Date : 2020-01-07 , DOI: 10.1002/bit.27254
Fayin Zhu 1 , Ka-Yiu San 2, 3 , George N Bennett 1, 3
Affiliation  

It is of great economic interest to produce succinate from low‐grade carbon sources, which can make it more economically competitive against petrochemical‐based succinate. Galactose sugars constitute a significant fraction of the soluble carbohydrate in a meal from agricultural sources which is considered a low value or waste byproduct of oilseed processing. To improve the galactose utilization, the effect of galR and glk on sugars uptake was investigated by deactivation of each gene in three previously engineered host strains. As expected, glk plays an important role in glucose uptake, while, the effect of deactivation of galR is highly dependent on the strength of the downstream module (succinate production module). A new succinate producer FZ661T was constructed by enhancement of the succinate producing module and manipulation of the gal operon. The succinate productivity reached 4.57 g/L/hr when a mixed sugar feedstock was used as a carbon source in shake‐flask fermentation, up to 812 mM succinate was accumulated in 80 hr in fed‐batch fermentation. When SoyMolaGal hydrolysate was used as a carbon source, 628 mM (74 g/L) succinate was produced within 72 hr. In this study, we demonstrate that FZ661T can produce succinate quickly with relatively high yield, giving it the potential for industrial application.

中文翻译:

在厌氧条件下,通过工程化的大肠杆菌改善了从富含半乳糖的原料生产琥珀酸酯的过程。

从低碳碳源生产琥珀酸酯具有极大的经济利益,这使其在石油化工基琥珀酸酯方面更具竞争力。半乳糖占农业来源粕中可溶碳水化合物的很大一部分,被认为是油料加工的低价值或废物副产品。为了提高半乳糖利用率,通过使三个先前经过工程改造的宿主菌株中的每个基因失活,研究了galRglk对糖吸收的影响。如预期的那样,glk在葡萄糖摄取中起重要作用,而galR失活的作用在很大程度上取决于下游模块(琥珀酸酯生产模块)的强度。通过增强琥珀酸酯生产模块和操纵gal操纵子,构建了新的琥珀酸酯生产商FZ661T 。当混合糖原料用作摇瓶发酵的碳源时,琥珀酸酯的生产率达到4.57 g / L / hr,在分批补料发酵中,在80小时内累积了812 mM琥珀酸酯。当将SoyMolaGal水解产物用作碳源时,在72小时内产生了628 mM(74 g / L)琥珀酸盐。在这项研究中,我们证明FZ661T可以以相对较高的产率快速生产琥珀酸酯,使其具有工业应用潜力。
更新日期:2020-03-09
down
wechat
bug