The structure and function of metabolic filaments

项目总结 中间代谢必须微调，仔细平衡，并能很好地适应 环境条件。虽然驱动大多数新陈代谢过程的单个酶都很好 理解，直到最近，这个领域才开始意识到代谢酶自身的广泛作用 新陈代谢组织和控制中的集合。特别是，我们现在知道几十种代谢酶 在体内和体外组装成丝状结构，这些细丝充当变构效应器 调整酶的活性。这项建议的重点是糖酵解代谢酶的自组装细丝和 核苷酸生物合成，从糖中提取能量并产生根本重要的 分别为大分子构筑块。我们将使用低温电子显微镜来确定结构 组装和调节的基础，结合生化、生物物理和细胞生物学方法 了解代谢细丝功能的综合方法。这项工作将提供对具体的 聚合作用在调节酶功能中的作用，并阐明代谢控制的一般原理 通过酵素细丝。这项行政补充申请是为购买质量光度计提供资金， 一种直接测量群体中单个分子大小的设备，它将使我们能够监测 我们研究中的酶的组装状态。这对于定量评估功能 酶组装的后果。

PROJECT SUMMARY Intermediate metabolism must be finely tuned, carefully balanced, and robustly adaptable to changes in environmental conditions. While the individual enzymes that drive most metabolic processes are well understood, only recently has the field come to appreciate the widespread role of metabolic enzyme self- assembly in metabolic organization and control. In particular, we now know that dozens of metabolic enzymes assemble into filamentous structures in vivo and in vitro, and that these filaments act as allosteric effectors to tune enzyme activity. This proposal focuses on self-assembled filaments of metabolic enzymes in glycolysis and nucleotide biosynthesis, processes that extract energy from sugar and generate fundamentally important macromolecular building blocks, respectively. We will use cryo-electron microscopy to determine the structural basis for assembly and regulation, coupled with biochemical, biophysical, and cell biological approaches in an integrative approach to understanding metabolic filament function. This work will provide insight into the specific roles polymerization plays in modulating enzyme function, and illuminate general principles of metabolic control by enzyme filaments. This request for an administrative supplement is to fund acquisition of a mass photometer, a device for directly measuring the sizes of individual molecules in a population, which will allow us to monitor assembly state of the enzymes in our studies. This is particularly critical for quantitatively assessing the functional consequences of enzyme assembly.