Physiological Role for Cation Channels in Bacteria

细菌中阳离子通道的生理作用

基本信息

批准号：
10198953
负责人：
DEBORAH A. SIEGELE
金额：
$ 38.6万
依托单位：
TEXAS A&M UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-07-01 至 2023-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10198953
关键词：
ATP Synthesis Pathway Acids Address Affect Antibiotics Bacillus subtilis Bacteria Bacterial Genome Bacterial Physiology Binding Biological Assay Biophysics Buffers Calorimetry Cations Cell physiology Cells Cellular Assay Chloride Channels Collection Consumption Data Development Electron Transport Equilibrium Escherichia coli Fluorescent Dyes Future Generations Genes Goals Growth In Vitro Ion Channel Ions Knock-out Knowledge Link Masks Measurable Measures Membrane Membrane Lipids Membrane Potentials Metabolism Modeling Molecular Mutation Organism Osmoregulation Phenotype Physiological Physiology Potassium Channel Prevalence Process Property Protein translocation Proteins Proton Pump Proton-Motive Force Protons Role Rotation Sequence Homology Solid Structure Suppressor Mutations Testing Titrations Ursidae Family Work antimicrobial base biophysical properties cell growth cell motility experimental study genome sequencing knockout gene link protein negative affect new therapeutic target novel pH gradient patch clamp pathogen pathogenic bacteria proteoliposomes public health relevance reconstitution whole genome

项目摘要

SUMMARY Tetrameric cation channels are widely conserved among all species. While bacterial cation channels are often used in structural and biophysical assays as models for their eukaryotic homologs, little is known about their physiological role in bacteria. Escherichia coli (E. coli) possesses a single tetrameric K+ channel, kch, which bears high sequence homology to eukaryotic K+ channels. The generation of a viable ∆kch strain created as part of a large E. coli single-gene knockout collection led to kch being categorized as a non-essential protein, and the functional role of this putative K+ channel has remained unknown. Preliminary data demonstrates that Kch is actually an essential protein and that ∆kch strains acquire suppressor mutations in order to remain viable. These suppressor mutations provide important clues as to which metabolic processes utilize the channel and has revealed a potential physiological role for Kch. Based on these results, the following aims are proposed: (1) to characterize the functional properties of the kch K+ channel; (2) to determine how Kch function affects E. coli physiology; and (3) to expand these findings to other bacteria to elucidate the conserved functions of bacterial cation channels. The results of this work will expand knowledge on the role of cation channels in bacterial physiology. Given the prevalence of these channels in pathogenic bacteria, understanding how cation channels benefit them may reveal how these proteins could be exploited as novel drug targets.

概括四聚阳离子通道在所有物种中都广泛保守。而细菌阳离子通道通常是在结构和生物物理测定中用作其真核同源物的模型，对其在细菌中的生理作用。大肠杆菌（大肠杆菌）具有单个四聚体K+通道KCH，该通道与真核K+通道具有高序列同源性。作为一部分产生的可行∆KCH菌株的产生大肠杆菌单基因敲除的集合导致KCH被归类为非必需蛋白质，并且该推定的K+通道的功能作用尚不清楚。初步数据表明KCH是实际上是一种必需的蛋白质，并且∆KCH菌株获得抑制突变以保持生存。这些抑制剂突变提供了有关哪些代谢过程利用该通道的重要线索，并且具有揭示了KCH的潜在生理作用。基于这些结果，提出了以下目的：（1）到表征KCH K+通道的功能特性；（2）确定KCH功能如何影响大肠杆菌生理; （3）将这些发现扩展到其他细菌以阐明细菌的配置功能阳离子通道。这项工作的结果将扩大有关阳离子通道在细菌中作用的知识生理。鉴于这些通道在致病细菌中的流行，因此了解阳离子通道如何受益可能会揭示如何将这些蛋白质作为新的药物靶标探索。