Charge matters: Pursuing the most common, and least understood molecular interactions in cells

收费问题：追求最常见、最不被理解的 细胞中的分子相互作用 项目摘要/摘要 S实验室的长期目标是确定和了解离子通量和静电是如何 相互作用调节促进细菌耐受压力的基本生物过程。 需要解决的中心问题：发生在任何生物体内的绝大多数分子相互作用 牢房仍然不太清楚。这怎么可能呢？到目前为止，几乎所有已被研究的分子相互作用， 而我们目前对生物学的理解所基于的是共价相互作用。这些互动是 坚固，使它们适合于实验测量。然而，绝大多数人之间的互动 细胞内的分子是基于静电学的非共价相互作用。静电相互作用 可能是脆弱和短暂的，因此他们的测量构成了巨大的技术挑战。因此，如何 这种相互作用是受调控的，它们在细胞中发挥什么功能在很大程度上尚不清楚。为了弥合这一点 ，我们提出了一项研究计划，以开发新的设备、技术和理论框架，以 研究静电相互作用的功能作用，特别是在细菌细胞和生物膜群落中。 影响：拟议的工作旨在研究离子相互作用的调节及其功能作用。 细菌，以更好地了解和控制他们对抗生素的耐受性。由此产生的发现将决定如何 离子强度和组成的变化会影响细胞的生理学。因此，我们将开始描述这种动态 原核生物的“金属组”。我们还将把定量实验和以物理为基础的理论结合起来 确定管理静电相互作用的一般原则的方法可以应用于我们的 细菌模型系统。考虑到任何给定细胞内的大量离子相互作用，很可能 我们的工作将揭示基本生物过程的一层新的分子调控。具体来说， 我们提出了“离子变构”假说，即细胞调节其细胞质离子。 合成以调节静电相互作用，从而全局调节转录和翻译。在……里面 特别是，离子相互作用可能在细菌细胞命运的决定中发挥关键作用，如进入和退出 从休眠中解脱出来，这是抗生素耐药性的主要原因。我们的工作将会揭示“中央”是否 生物学教条“是由细胞质的离子组成和强度的变化调节的，并提供 一种理解和控制细菌基本应激反应调节的新范式。

Charge matters: Pursuing the most common, and least understood molecular interactions in cells PROJECT SUMMARY / ABSTRACT The long-term objective of the Süel lab is to determine and understand how ion fluxes and electrostatic interactions regulate fundamental biological processes that promote stress tolerance in bacteria. The central problem to be addressed: The vast majority of molecular interactions that occur within any living cell have remained obscure. How can this be? Nearly all molecular interactions that have been studied to date, and on which our current understanding of biology is based on, are covalent interactions. These interactions are strong, making them suitable for experimental measurements. However, the vast majority of interactions among molecules within the cell are non-covalent interactions that are based on electrostatics. Electrostatic interactions can be weak and short-lived, and thus their measurements pose a great technical challenge. Consequently, how such interactions are regulated and what functions they play in cells remains largely unknown. To bridge this gap, we propose a research program to develop new devices, techniques, and a theoretical framework to investigate the functional roles of electrostatic interactions, specifically in bacterial cells and biofilm communities. Impact: The proposed work aims to investigate the regulation of ionic interactions and their functional roles in bacteria, to better understand and control their tolerance to antibiotics. The resulting findings will determine how changes in ionic strength and composition affect cell physiology. We will thus begin to characterize the dynamics of the prokaryotic “metallome”. We will also integrate quantitative experiments with physics-based theoretical approaches to identify general principles governing electrostatic interactions that can be applied beyond our bacterial model systems. Given the tremendous number of ionic interactions within any given cell, it is very likely that our work will uncover a new layer of molecular regulation of fundamental biological processes. Specifically, we postulate the hypothesis of “ionic allostery”, where we propose that cells regulate their cytoplasmic ion composition to modulate electrostatic interactions, and thereby globally regulate transcription and translation. In particular, ionic interactions may play a crucial role in bacterial cell fate decisions, such as entry into, and exit from dormancy, which is the major cause of antibiotic resistance. Our work will thus reveal whether “the central dogma of biology” is modulated by changes in the ionic composition and strength of the cytoplasm and provide a new paradigm for understanding and controlling the regulation of fundamental stress responses in bacteria.