通过钝化global regulator FruR调整大肠杆菌中碳流量来提高色氨酸的产量
Title：Modulating the direction of carbon ﬂow in Escherichia coli to improve 1-tryptophan production by inactivating the global regulator FruR
Author：Lina Liua,b, Xuguo Duana,b, Jing Wua,b,∗
The fructose repressor (FruR) affects carbon ﬂux through the central metabolic pathways of Escherichia coli. In this study, l-tryptophan production in Escherichia coli FB-04 was improved by knocking out the fruR gene, thereby inactivating FruR. This fruR knockout strain, E. coli FB-04(L1fruR), not only exhibited higher growth efﬁciency, it also showed substantially improved l-tryptophan production. l-tryptophan production by E. coli FB-04(L1fruR) and l-tryptophan yield per glucose were increased by 62.5% and 52.4%, respectively, compared with the parent E. coli FB-04. Metabolomics analysis showed that the fruR knockout signiﬁcantly enhances metabolic ﬂow through glycolysis, the pentose phosphate pathway and the TCA cycle, increasing levels of critical precursors and substrates for l-tryptophan biosynthesis. These results indicate that fruR deletion should enhance l-tryptophan production and improve the efﬁciency of carbon source utilization independent of genetic background.