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How Listeria senses and responds to different host environments

李斯特菌如何感知和响应不同的宿主环境

基本信息

批准号：
10627781
负责人：
DANIEL A PORTNOY
金额：
$ 36.6万
依托单位：
UNIVERSITY OF CALIFORNIA BERKELEY
依托单位国家：
美国
项目类别：
财政年份：
1988
资助国家：
美国
起止时间：
1988-06-15 至 2024-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10627781
关键词：
Aerobic Affect Antioxidants Bacteria Binding Biochemical Biological Assay Biological Models Cell Compartmentation Cell Death Cell membrane Cell surface Cells Cellular biology Chemicals Cholesterol Communities Cues Cytochrome c Reductase Cytolysins Data Detection Disease Electron Transport Electrons Enterococcus Environment Equilibrium Event Family Firmicutes Flavins Fumarates Funding Gastrointestinal tract structure Gene Expression Genetic Screening Glutathione Gram-Positive Bacteria Growth Immunity In Vitro Infection Innate Immune Response International Intestines Investigation Iron Lipoproteins Listeria Listeria monocytogenes Listeria monocytogenes hlyA protein Listeriosis Macrophage Mediating Membrane Modeling Monitor Mutation NADH Natural Immunity Oral Oxidants Oxidation-Reduction Oxidative Stress Oxygen Pathogenesis Phagocytosis Phagosomes Play Property Reducing Agents Regulation Resistance Role Source Specific qualifier value Streptococcus Stress Succinate Dehydrogenase Superoxides System Transcriptional Regulation Up-Regulation Virulence Virulent adaptive immunity disorder prevention extracellular foodborne pathogen genomic locus glutathione synthase gut colonization human pathogen in vivo insight lactic acid bacteria member microbiota mutant novel pathogen response transcription factor virulence gene

项目摘要

Project Summary/Abstract Listeria monocytogenes is facultative intracellular food-borne pathogen that provides an extremely amenable model for basic studies on host-pathogen interactions. This proposal is based on the results of a genetic screen that revealed a critical role of bacterial redox sensing for the upregulation of virulence gene expression in vivo. We found that L. monocytogenes glutathione synthase was upregulated during infection and determined that glutathione is the allosteric activator of the major virulence transcription factor PrfA. Based on these findings, and after decades of investigation by multiple groups, we successfully recapitulated intracellular virulence gene expression by simply adding reducing agents to bacteria grown in a chemically defined synthetic media. This finding led to another genetic screen to identify bacterial mutants that were either more sensitive or resistant to the growth inhibitory property of high concentrations of reducing agents. Analysis of the resistant mutants that arose from this screen led to the discovery that L. monocytogenes possess a Flavin-based Extracellular Electron Transport chain (FLEET) that can transport over 100,000 electrons/bacterium/second to flavin moieties present on two extracellular lipoproteins, PplA and FrdA, which can transfer electrons to ferric iron and fumarate via activation of FrdA, which encodes a fumarate reductase. We show that FLEET can mediated anaerobic growth using either ferric iron or fumarate as electron acceptors. Mutants that were more sensitive to reducing agents clustered in perR, a redox-sensing transcription factor that controls the transcriptional response to oxidative stress. We hypothesize that the oxidative stress is being generated by FLEET that we show is producing superoxide in the presence of oxygen. FLEET orthologues were found in 100s of Firmicute species including pathogens and members of the microbiota and we propose that it represents a versatile electron transfer hub present in diverse Gram-positive bacteria, that provides a selective advantage to bacteria growing anaerobically in the intestine. We also propose that FLEET activity has other consequences aerobically that may have profound effects on the cell biology of infection, virulence, and immunity.

项目概要/摘要单核细胞增生李斯特氏菌是兼性细胞内食源性病原体，它提供了极其宿主与病原体相互作用基础研究的合适模型。该提案基于一项研究的结果遗传筛选揭示了细菌氧化还原传感对毒力基因上调的关键作用体内表达。我们发现单核细胞增生李斯特氏菌谷胱甘肽合酶在感染过程中上调并确定谷胱甘肽是主要毒力转录因子 PrfA 的变构激活剂。基于这些发现，经过多个小组数十年的调查，我们成功地通过简单地向生长于其中的细菌中添加还原剂来概括细胞内毒力基因的表达化学成分明确的合成介质。这一发现导致了另一项基因筛查来识别细菌突变体对高浓度的生长抑制特性更敏感或具有抵抗力还原剂。对这次筛选产生的抗性突变体的分析发现，L. 单核细胞增生李斯特菌拥有基于黄素的细胞外电子传输链（FLEET），可以传输超过 100,000 个电子/细菌/秒存在于两种细胞外脂蛋白 PplA 上的黄素部分 FrdA，它可以通过激活 FrdA 将电子转移到三价铁和富马酸盐，FrdA 编码富马酸还原酶。我们证明 FLEET 可以使用三价铁或三价铁介导厌氧生长富马酸盐作为电子受体。对还原剂更敏感的突变体聚集在 perR 中，氧化还原感应转录因子，控制氧化应激的转录反应。我们假设氧化应激是由 FLEET 产生的，我们证明 FLEET 正在产生超氧化物氧气的存在。在数百种厚壁菌门物种（包括病原体）中发现了 FLEET 直系同源物和微生物群的成员，我们认为它代表了一个多功能的电子转移中心在多种革兰氏阳性细菌中，这为厌氧生长的细菌提供了选择优势肠道。我们还建议 FLEET 活动在有氧运动方面还有其他后果，可能会导致对感染、毒力和免疫的细胞生物学产生深远影响。

项目成果

期刊论文数量（123）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

RNA-Based Fluorescent Biosensors for Live Cell Imaging of Second Messenger Cyclic di-AMP.

DOI：
10.1021/jacs.5b00275
发表时间：
2015-05-27
期刊：
Journal of the American Chemical Society
影响因子：
15
作者：
Kellenberger CA;Chen C;Whiteley AT;Portnoy DA;Hammond MC
通讯作者：
Hammond MC

Suppression of cell-mediated immunity following recognition of phagosome-confined bacteria.

DOI：
10.1371/journal.ppat.1000568
发表时间：
2009-09
期刊：
PLoS pathogens
影响因子：
6.7
作者：
Bahjat KS;Meyer-Morse N;Lemmens EE;Shugart JA;Dubensky TW;Brockstedt DG;Portnoy DA
通讯作者：
Portnoy DA

An Mtb-Human Protein-Protein Interaction Map Identifies a Switch between Host Antiviral and Antibacterial Responses.

DOI：
10.1016/j.molcel.2018.07.010
发表时间：
2018-08-16
期刊：
Molecular cell
影响因子：
16
作者：
Penn BH;Netter Z;Johnson JR;Von Dollen J;Jang GM;Johnson T;Ohol YM;Maher C;Bell SL;Geiger K;Golovkine G;Du X;Choi A;Parry T;Mohapatra BC;Storck MD;Band H;Chen C;Jäger S;Shales M;Portnoy DA;Hernandez R;Coscoy L;Cox JS;Krogan NJ
通讯作者：
Krogan NJ

Strategies Used by Bacteria to Grow in Macrophages.