代谢工程强化tolC缺失大肠杆菌的血红素合成  

Metabolic engineering of tolC-deleted Escherichia coli for enhancement of heme synthesis

作　　者：张鑫[1,2] 杨燕[1] 段小燕 唐蕾 ZHANG Xin;YANG Yan;DUAN Xiaoyan;TANG Lei(School of Biotechnology,Jiangnan University,Wuxi 214122,China;Key Laboratory of Industrial Biotechnology,Ministry of Education,Jiangnan University,Wuxi 214122,China)

机构地区：[1]江南大学生物工程学院,江苏无锡214122 [2]工业生物技术教育部重点实验室(江南大学),江苏无锡214122

出　　处：《食品与发酵工业》2023年第17期10-15,共6页Food and Fermentation Industries

基　　金：111引智计划项目(111-2-06);国家轻工技术与工程一流学科自主课题资助项目(LITE2018-27);江苏省现代工业发酵协同创新中心资助项目(BY2013015-11)。

摘　　要：血红素作为生物体可利用的铁源应用于食品和医疗领域。利用微生物发酵生产血红素具有工业前景但产量偏低,该研究利用代谢工程改造大肠杆菌,提高菌体血红素合成水平。通过构建tolC缺失大肠杆菌,进而过表达hemA、hemH,外源添加Fe^(2+)的方式实现血红素产量的提升。结果表明,在tolC缺失菌株WTΔT中过表达hemA导致卟啉的积累;在外源添加80μmol/L的Fe^(2+)时,共表达hemA与hemH的菌株WTΔT-AH,胞内血红素含量达到40.18μmol/L,是野生菌WT的3.98倍。该研究为使用重组大肠杆菌高效生产血红素提供了一定的理论依据和潜在的应用价值。As an iron source that can be utilized by organisms,heme is applied to the fields of food and pharmaceutical industry.The production of heme by microbial fermentation has industrial potentials but the yield is low.In this study,the synthetic level of heme in Escherichia coli were improved through metabolic engineering.The heme yield was increased by constructing tolC-deleted Escherichia coli(WTΔT),overexpressing hemA and hemH,and adding Fe^(2+)exogenously.The results showed that over-expression of hemA in the tolC-deleted strain resulted in the accumulation of porphyrins.When 80μmol/L Fe^(2+)was added,the strain co-expressing hemA and hemH(WTΔT-AH)exhibited intracellular heme content of 40.18μmol/L,3.98-fold of that in WT.The above results provide a certain theoretical basis and value for improvement of heme yield by recombinant Escherichia coli.

关 键 词：大肠杆菌 TOLC 同源重组 血红素 卟啉 

分 类 号：TQ920.1[轻工技术与工程—发酵工程] O626[理学—有机化学]