操纵子
代谢工程
转录因子
生物
生物化学
生物合成
地衣芽孢杆菌
丙酮
代谢途径
转录调控
基因
细胞生物学
细菌
枯草芽孢杆菌
突变体
遗传学
发酵
作者
Shiying Hu,Penghui He,Yongjia Zhang,Jian Meng,Qin Wang,Su Yang,Shouwen Chen
标识
DOI:10.1016/j.ymben.2022.10.003
摘要
Lichenysin, producted by Bacillus licheniformis, is an important cyclic lipopeptide biosurfactant, which has potential applications in oil exploitation, drug development, biological control of agriculture and bioremediation. While studies are lacking on metabolism regulation of lichenysin biosynthesis, which limits metabolic engineering and large-scale production of lichenysin. In this study, the yield of lichenysin was improved obviously by 13.6 folds to 2.18 ± 0.03 g/L in degU deletion strain (WX02△degU) compared with the wild-type strain (WX02) and completely inhibited in degU overexpressed strain (WX02/pHY-degU). We further proved that DegU, a transcription factor plays a significant role in multicellular behavior, is a key negative regulator of lichenysin synthesis lchA operon. But interestingly, lichenysin yield was still inhibited by overexpressing DegU in the promoter-substituted strain (WX02-PP43lch), in which promoter of lchA operon cannot be controlled by DegU. Thus, through 13C-metabolic flux analysis, we found that deletion of degU also enhanced glucose uptake, branched chain amino acid synthesis, and fatty acid synthesis, while decrease acetoin synthesis, which is beneficial for the supply of lichenysin precursors. Further experiments demonstrate that DegU regulates these pathways by binding to the promoter regions of related genes. Overall, we systematically investigated the multi-pathway regulation network mediated by DegU on lichenysin biosynthesis, which not only contributes to the further metabolic engineering for lichenysin high-production, but sheds light on studies of transcription factor regulation.
科研通智能强力驱动
Strongly Powered by AbleSci AI