高效合成indigoidine的大肠杆菌Nissle 1917代谢工程改造

Metabolic Engineering of Escherichia coli Nissle 1917 for Efficient Synthesis of Indigoidine

摘要:

目的 构建一株高产生物色素indigoidine的菌株，为其在食品着色剂等领域的应用提供菌种资源。方法 以大肠杆菌（Escherichia coli，E. coli）Nissle 1917为出发菌株，首先消除菌株中的隐蔽质粒pMUT-1与pMUT-2，随后对indigoidine合成酶及4’-磷酸泛酸转移酶进行组合筛选及基因组整合，并通过强化途径基因表达、优化分批补料发酵等策略，提升菌株的indigoidine合成能力。结果 成功构建高产菌株EcN26，在1 L发酵罐中分批补料发酵46.00 h，indigoidine产量达3.63 g/L，生产强度为0.079 g/（L·h）。结论 该研究成功获得indigoidine高产菌株，为该生物色素的工业化生产及应用提供了技术方案与理论依据。

Abstract:

Objective This study aimed to construct a strain with a high yield of the bio-pigment indigoidine, thus providing strain resources for application in fields such as food colorants.Method Escherichia coli (E. coli) Nissle 1917 was used as the parent strain. Metabolic engineering strategies included removing the cryptic plasmids pMUT-1 and pMUT-2, screening for a combination of key enzymes (indigoidine synthase and 4’-phosphopantetheinyl transferase) followed by genomic integration, enhancing the expression of pathway genes, and conducting fed-batch fermentation. Through these approaches, the indigoidine production capability of the engineered strain was systematically improved.Result The final high-yield strain, EcN26, was used for fed-batch fermented in a 1 L fermenter for 46.00 h, achieving an indigoidine titer of 3.63 g/L and the productivity of 0.079 g/(L·h).Conclusion This study provides a technical scheme and a theoretical basis for the industrial production and application of indigoidine.