ME: Collaborative Research: Metabolic Engineering of E. coli Sugar-Utilization Regulatory Systems for the Consumption of Plant Biomass Sugars

该项目的总体目标是代谢工程大肠杆菌糖利用调节系统（SURS）利用从植物生物质中获得的糖混合物。首席研究员（pi）将引入特定的遗传修饰的SURS，并在细胞水平上分析这些变化的后果。具体目标是：(1)构建带有修饰的sers的大肠杆菌菌株，并评估其有效利用糖混合物（葡萄糖、木糖和阿拉伯糖）的能力；(2)在基因组尺度上评估改造大肠杆菌链球菌后基因表达调控的变化；(3)利用基于二维核磁共振键标记实验的键聚体分析的新型通量分析技术，确定了苏氏突变体和野生型菌株的功能代谢途径并量化其通量；(4)利用结合基因表达和代谢通量数据的基于遗传网络的代谢通量分析（MFA）模型对这些结果进行整合；(5)提出进一步的遗传/环境改造，以提高SURS突变体发酵糖混合物的能力。这个项目的好处将是双重的。首先，从应用的角度来看，该项目将为设计合理的SURS修饰以获得能够有效代谢糖混合物的重组菌株提供强大的工具。其次，从基础的角度来看，该项目将有助于更好地理解SURS在调节糖利用和其他几种细胞功能中的作用。

The overall objective of this project is to metabolically engineer the E. coli Sugar-Utilization Regulatory Systems (SURS) to utilize sugar mixtures obtained from plant biomass. The Principal Investigators (PIs) will introduce specific genetic modifications to the SURS and analyze the consequences of these changes at the cellular level. The specific goals are to: (1) construct E. coli strains with modified SURS and evaluate their capability to efficiently utilize sugar mixtures (glucose, xylose and arabinose); (2) evaluate changes in the regulation of gene expression at the genomic scale resulting from engineering E. coli SURS; (3) identify functional metabolic pathways and quantify their fluxes in SURS mutants and wild type strains by using a novel flux analysis technique based on bondomer analysis of 2D NMR bond-labeling experiments; (4) integrate these results using a novel genetic network-based metabolic flux analysis (MFA) model that combines gene expression and metabolic flux data; and (5) propose further genetic/environmental modification for improving the capacity of SURS mutants for fermenting sugar mixtures. The benefits from this project will be two-fold. First, from an applied standpoint, the project will provide a powerful tool for designing of rational modifications of the SURS to obtain recombinant strains capable of efficiently metabolizing sugar mixtures. Second, from a fundamental standpoint, this project will contribute to a better understanding of the role of SURS in regulating both sugar utilization and several other cellular functions.