Calcium signaling in Mycobacterium tuberculosis

结核分枝杆菌中的钙信号传导

基本信息

批准号：
10726978
负责人：
Christoph Grundner
金额：
$ 30.92万
依托单位：
SEATTLE CHILDREN'S HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-05-19 至 2025-04-30
项目状态：
未结题

项目摘要

ABSTRACT Calcium (Ca2+) is a major signaling mechanism in eukaryotic cells, but although Ca2+ signaling has ancient origins, it is not well understood in bacteria. Several bacteria have been shown to maintain a low intracellular Ca2+ concentration, which is the basis for Ca2+ signaling in eukaryotes. In addition, some bacterial Ca2+- binding proteins and putative transporters have been identified, suggesting the presence of a bacterial Ca2+ signaling system analogous to that in eukaryotes. However, many fundamental questions about bacterial Ca2+ signaling remain, from maintenance of Ca2+ gradients to Ca2+ triggers, Ca2+ binding proteins, Ca2+ storage, and finally the effects of changing Ca2+ concentrations on bacterial physiology and pathogenesis. Using a FRET-based Ca2+ reporter system in Mycobacterium tuberculosis (Mtb) that allows for precise, real time measuring of intracellular Ca2+ levels, we will explore these fundamental questions about Ca2+ signaling in Mtb. We will use a novel proteomic approach, thermal protein profiling, to globally detect Ca2+ binding proteins in Mtb. We also identified a novel Ca2+ porin and will use a porin knockout strain to test for the role of Ca2+ in Mtb pathogenesis. Together, we will leverage these new tools to test the hypothesis that Mtb maintains a Ca2+ signaling system analogous to that in many eukaryotes and will begin to dissect the physiologic and pathogenic implications of Ca2+ homeostasis in Mtb.

抽象的钙 (Ca2+) 是真核细胞中的主要信号传导机制，但尽管 Ca2+ 信号传导历史悠久但它在细菌中的起源尚不清楚。一些细菌已被证明能够维持低细胞内 Ca2+ 浓度，是真核生物中 Ca2+ 信号传导的基础。此外，某些细菌的Ca2+- 结合蛋白和假定的转运蛋白已被鉴定，表明细菌 Ca2+ 的存在信号系统类似于真核生物中的信号系统。然而，关于细菌 Ca2+ 的许多基本问题信号仍然存在，从维持 Ca2+ 梯度到 Ca2+ 触发器、Ca2+ 结合蛋白、Ca2+ 储存，最后是改变 Ca2+ 浓度对细菌生理学和发病机制的影响。使用结核分枝杆菌 (Mtb) 中基于 FRET 的 Ca2+ 报告系统可实现精确、实时的检测测量细胞内 Ca2+ 水平，我们将探讨有关 Ca2+ 信号传导的这些基本问题山地车。我们将使用一种新颖的蛋白质组学方法，即热蛋白分析，来全面检测 Ca2+ 结合蛋白在山地。我们还鉴定了一种新型 Ca2+ 孔蛋白，并将使用孔蛋白敲除菌株来测试 Ca2+ 在结核分枝杆菌发病机制。我们将共同利用这些新工具来检验 Mtb 维持 Ca2+ 的假设信号系统类似于许多真核生物中的信号系统，并将开始剖析生理和 Mtb 中 Ca2+ 稳态的致病影响。