Metabolic control analysis of glycolysis

代谢工程是一种越来越多地被用于开发新作物品种的工具。代谢工程在作物改良策略中的常规应用需要对体内代谢途径的调节机制有一个完整的了解。糖酵解参与代谢能量的产生和碳水化合物的分解，为多种植物生物合成途径提供碳骨架。它还参与植物对几种环境胁迫的适应。因此，植物糖酵解代谢工程在改良作物以生产有价值的天然产物或更好地抵抗环境胁迫方面具有潜在的应用前景。然而，我们目前对这一代谢途径如何调控的了解仍然不完整。我的研究计划的长期目标是更好地了解植物糖酵解的调节，特别是单个酶的量如何影响糖酵解途径中的碳通量。本研究旨在研究控制植物糖酵解途径的三种酶(己糖激酶、胞质磷酸三糖异构酶和胞质核苷二磷酸)的特性。为此，我们将使用一种多学科的方法，包括酶的纯化和表征，通过转基因手段操纵酶活性，突变和转基因植物的代谢谱，以及蛋白质的翻译后修饰。拟议的研究将为博士、硕士和本科生提供培训。从长远来看，这项研究的应用将允许一种基本的方法来设计植物的碳代谢。

Metabolic engineering is a tool that is increasingly used for the development of new crop varieties. The routine use of metabolic engineering in crop improvement strategies necessitates a complete understanding of mechanisms by which metabolic pathways are regulated in vivo. Glycolysis is involved in the generation of metabolic energy and in the breakdown of carbohydrates to provide carbon skeletons to a large variety of plant biosynthetic pathways. It is also involved in plant adaptations to several environmental stresses. Thus, metabolic engineering of plant glycolysis has potential applications in improvement of crops that are tailored to produce valuable natural products or to resist better to environmental stresses. However, our current knowledge on how this metabolic pathway is regulated is still incomplete. The long term objective of my research program is to better understand the regulation of plant glycolysis, and in particular how the amount of individual enzymes influences carbon flux in the glycolytic pathway. The research described in the present proposal aims at the characterization of three enzymes (hexokinase, cytosolic triosephosphate isomerase and cytosolic nucleoside diphosphate kinase) in the control over the plant glycolytic pathway. For this, we will use a multidisciplinary approach encompassing enzyme purification and characterization, manipulation of enzyme activity by transgenic means, metabolic profiling of mutants and transgenic plants and post-translational modification of proteins. The proposed research will provide training for PhD, MSc and undergraduate students. In the long term, applications of this research will allow a rationale approach to engineer carbon metabolism in plants.