四氢嘧啶感应分子机制及四氢嘧啶生物传感器研究

Metabolite biosensors, an important part of synthetic biology has attracted much attention recently because it can accomplish high throughput analysis of metabolite. Ectoines are referred to as chemical chaperones and help to counteract various stresses. Therefore, ectoines display tremendous application potentials in cosmetics, healthcare and scientific research fields. Recently in our lab, the transcription regulator ehuR was first reported to repress the expression of genes responsible for ectoine uptake and catabolism. This project will focus on the exploration of the mechanism of ecotines sensing for ehuR and clarify the molecular mechanism of ectiones involved in the regulation of ehuR. Meanwhile, for the first time, the ehuR provide us with a natural ectoine biosensor, which will benefit the following research of metabolic engineering and synthetic biology. Furthermore, ectoines can strengthen the robustness of chassis cells and improve the stability of crucial enzymes in the metabolic pathway. Therefore, the ectoines induction system can be applied to produce various value added products and improve the robustness and efficiency of microbial cell factories. Thus, this project is significant for both the scientific research and the industrial application.

代谢产物生物传感器作为重要的合成生物学元件，可以实现代谢产物的实时快速高通量检测，近年来备受关注。四氢嘧啶被称为“化学分子伴侣”，能够帮助细胞抵御各种逆境，在美容、医疗以及科研等领域都展现出非常巨大的应用前景。近期,本课题组首次发现并证实转录调控因子ehuR能够特异性阻遏四氢嘧啶吸收和代谢相关基因的表达。在此基础上，本项目将着重研究ehuR感应四氢嘧啶的分子机制，解析四氢嘧啶如何参与ehuR对其靶基因的调控。同时，ehuR感应四氢嘧啶机制的解析，也将首次为我们提供一种天然的四氢嘧啶生物传感器，为后续代谢工程和合成生物学研究提供重要的传感器元件。另外，四氢嘧啶作为细胞保护性物质，有助于提高底盘微生物的鲁棒性和合成通路中关键酶的稳定性。四氢嘧啶诱导系统可广泛应用于微生物细胞工厂合成高附加值产品，提高微生物细胞工厂鲁棒性和合成效率。因此，本项目体现出非常重要的理论研究意义和广阔的实践应用前景。

代谢产物生物传感器作为重要的合成生物学元件，可以实现代谢产物的实时快速高通量检测，近年来备受关注。四氢嘧啶被称为“化学分子伴侣”，能够帮助细胞抵御各种逆境，在美容、医疗以及科研等领域都展现出非常巨大的应用前景。本项目通过在体外重构ehuR调控体系，系统分析了ehuR下游基因在ehuR调控过程中发挥的重要作用。研究结果表明，eutA在四氢嘧啶解除ehuR阻遏作用过程中发挥了重要作用。从而为设计四氢嘧啶生物传感器奠定了重要的理论基础。在此基础上，成功构建了基于ehuR和eutA的生物传感器，该传感器能够对胞内外四氢嘧啶做出响应，响应强度能在一定范围内反映胞内外四氢嘧啶浓度，在四氢嘧啶生产菌株筛选和发酵控制中展现出了较好的应用前景。