Activation of glycerol metabolic pathway by evolutionary engineering of Rhizopus oryzae to strengthen the fumaric acid biosynthesis from crude glycerol
Activation of glycerol metabolic pathway by evolutionary engineering of Rhizopus oryzae to strengthen the fumaric acid biosynthesis from crude glycerol
复制标题
通过米根霉进化工程激活甘油代谢途径以加强粗甘油富马酸生物合成
DOI：
10.1016/j.biortech.2015.07.104
复制
发表时间：
2015-11-01
影响因子：
11.4
通讯作者：
Xia, Menglei
中科院分区：
文献类型：
--
作者：
Huang, Di;Wang, Ru;Xia, Menglei
米根霉受到生物柴油副产物粗甘油的严格抑制，导致富马酸产量较低。在本研究中，利用进化工程来激活甘油利用富马酸的途径。选育出一株耐高浓度甘油发酵生产富马酸14.9g/L的优良菌株G80，富马酸产量为0.248 g/g甘油。关键酶活性分析表明，与亲本菌株相比，进化菌株在甘油异化、丙酮酸消耗和还原三元酸途径方面均有显著上调。随后，细胞内代谢谱分析表明，氨基酸生物合成、三羧酸循环、脂肪酸和应激反应代谢产物是导致两株菌株代谢差异的原因。此外，优化了甘油补料分批发酵策略，获得了富马酸的最高产量25.5g/L，较亲本菌株1.2g/L显著提高20.9倍。(C)2015爱思唯尔有限公司版权所有。
Rhizopus oryzae is strictly inhibited by biodiesel-based by-product crude glycerol, which results in low fumaric acid production. In this study, evolutionary engineering was employed to activate the glycerol utilization pathway for fumaric acid production. An evolved strain G80 was selected, which could tolerate and utilize high concentrations of crude glycerol to produce 14.9 g/L fumaric acid with a yield of 0.248 g/g glycerol. Key enzymes activity analysis revealed that the evolved strain displayed a significant upregulation in glycerol dissimilation, pyruvate consumption and reductive tricarboxylic acid pathways, compared with the parent strain. Subsequently, intracellular metabolic profiling analysis showed that amino acid biosynthesis, tricarboxylic acid cycle, fatty acid and stress response metabolites accounted for metabolic difference between two strains. Moreover, a glycerol fed-batch strategy was optimized to obtain the highest fumaric acid production of 25.5 g/L, significantly increased by 20.9-fold than that of the parent strain of 1.2 g/L. (C) 2015 Elsevier Ltd. All rights reserved.