Global control of bacterial translation by specific ribosome modification

通过特定核糖体修饰对细菌翻译进行全局控制

• 批准号: BB/M002586/1
• 负责人: Jacob Malone
• 金额: $ 55.78万
• 依托单位: University of East Anglia
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2014
• 资助国家: 英国
• 起止时间: 2014 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FM002586%2F1
• 关键词: Global; control; bacterial; translation; specific

Bacteria can interact with plants in a number of different ways. In addition to pathogenic bacteria that cause costly plant diseases, several species form mutually beneficial relationships with plants. These bacteria live off the organic molecules exuded by plant roots and in return they positively affect plant health and nutrition and suppress pathogenic fungal growth. My lab studies two plant-associated Pseudomonas species. These are the aggressive plant pathogen P. syringae, which causes economically destructive diseases including tomato speck, brown spot and bleeding canker, and the harmless, soil-dwelling species P. fluorescens. P. fluorescens colonises plant roots and displays effective biocontrol properties against pathogens, making it an attractive potential alternative to conventional chemical pesticides. The efficacy of P. syringae pathogenicity or P. fluorescens biocontrol is directly related to the ability of the bacteria to colonise their plant host. However, despite extensive research into plant infection, biocontrol and root colonisation, the internal bacterial signalling pathways that control these processes are only poorly understood. We seek to improve our understanding of these internal signals, with the eventual aims of fighting P. syringae infection, and modifying P. fluorescens to produce new, more effective biocontrol agents. As part of our ongoing research into Pseudomonas signalling during plant interactions, we have investigated the RimK protein, which is predicted to interact with the protein production machinery of the bacterial cell. RimK appears to modify a small protein in the bacterial ribosome called RpsF. Subsequent experiments suggest that RimK activity towards RpsF affects ribosome stability, leading to altered ribosomal function and consequently to specific changes in the protein makeup of the cell. The rimK gene is part of an operon that also includes rimA, a gene encoding a cyclic-di-GMP (cdG) degrading enzyme. CdG is a bacterial signalling molecule that regulates diverse bacterial characteristics including motility and attachment to surfaces. The RimA and RimK proteins physically interact, consistent with a role for RimA (and possibly cdG) in RimK regulation. Deletion of the rimK gene led to decreased P. syringae virulence and reduced the efficiency of wheat root colonisation by P. fluorescens. Furthermore, the rimA and rimK genes were up-regulated during the later stages of P. fluorescens root colonisation, suggesting that RimK activity contributes to the adaptive response of Pseudomonas species to the plant environment.With this proposal we will first determine how the RimK protein functions, and how it changes the stability and function of the ribosome. Next, we will examine the significance of RimA cdG metabolism, and how the Rim proteins interact with each other. We will also examine the total protein content of bacteria with the rimA gene deleted. Comparison of these results with those for a rimK deletion mutant will tell us whether or not the two genes function as part of the same signalling pathway. Finally, we will examine the function of RimK protein in P. syringae and in the P. fluorescens wheat root environment. To do this we will extract the total protein content of wild-type and rimK-mutant bacteria, either from P. syringae cultures or from P. fluorescens grown in model wheat root systems. We will then measure protein levels and use this data to determine how rimK deletion affects protein translation in different species and different environments. These data will allow us to determine both the effects of RimK activity, the protein changes that occur as a consequence of growth in the plant environment, and the importance of RimK activity for pathogenic and beneficial plant-microbe interactions.

细菌可以以多种不同的方式与植物相互作用。除了引起昂贵的植物疾病的病原菌外，几个物种与植物形成互利关系。这些细菌靠植物根部分泌的有机分子为生，反过来，它们对植物健康和营养产生积极影响，并抑制病原真菌的生长。我的实验室研究了两种与植物相关的假单胞菌。它们是侵略性植物病原体P.lingae，它导致经济上破坏性的疾病，包括番茄斑点病，褐斑病和出血溃疡病，以及无害的土壤栖息物种P.fluorescens。荧光假单胞菌定殖植物根部，并显示出对病原体有效的生物防治特性，使其成为传统化学农药的有吸引力的潜在替代品。P.lingae致病性或P.fluorescens生物防治的功效与细菌定殖其植物宿主的能力直接相关。然而，尽管对植物感染、生物防治和根定殖进行了广泛的研究，但控制这些过程的内部细菌信号传导途径却知之甚少。我们试图提高我们对这些内部信号的理解，最终目标是对抗P. puriingae感染，并修改P. fluorescens以产生新的，更有效的生物防治剂。作为我们正在进行的研究假单胞菌信号在植物相互作用的一部分，我们已经调查了RimK蛋白，这是预测与细菌细胞的蛋白质生产机制相互作用。RimK似乎修饰了细菌核糖体中一种名为RpsF的小蛋白。随后的实验表明，RimK对RpsF的活性影响核糖体稳定性，导致核糖体功能改变，从而导致细胞蛋白质组成的特定变化。rimK基因是操纵子的一部分，该操纵子还包括rimA，rimA是编码环状二GMP（cdG）降解酶的基因。CdG是一种细菌信号分子，可调节多种细菌特性，包括运动性和表面附着。RimA和RimK蛋白在物理上相互作用，这与RimA（可能还有cdG）在RimK调节中的作用一致。rimK基因的缺失导致P.lingae毒力降低，并降低了荧光假单胞菌在小麦根中的定殖效率。此外，rimA和rimK基因在荧光假单胞菌根定殖的后期上调，表明RimK活性有助于假单胞菌物种对植物环境的适应性反应。接下来，我们将研究RimA cdG代谢的意义，以及Rim蛋白如何相互作用。我们还将检查rimA基因缺失的细菌的总蛋白质含量。将这些结果与rimK缺失突变体的结果进行比较，将告诉我们这两个基因是否作为相同信号通路的一部分起作用。最后，我们将研究RimK蛋白在P.lingae和荧光假单胞菌小麦根环境中的功能。为了做到这一点，我们将提取野生型和rimK突变体细菌的总蛋白质含量，无论是从P.lingae培养物还是从在模型小麦根系中生长的荧光假单胞菌。然后，我们将测量蛋白质水平，并使用这些数据来确定rimK缺失如何影响不同物种和不同环境中的蛋白质翻译。这些数据将使我们能够确定RimK活性的影响，在植物环境中生长的结果发生的蛋白质变化，以及RimK活性对病原性和有益的植物-微生物相互作用的重要性。

项目成果

Analyzing the Complex Regulatory Landscape of Hfq - an Integrative, Multi-Omics Approach.

• DOI: 10.3389/fmicb.2017.01784
• 发表时间: 2017
• 期刊: Frontiers in microbiology
• 影响因子: 5.2
• 作者: Grenga L;Chandra G;Saalbach G;Galmozzi CV;Kramer G;Malone JG
• 通讯作者: Malone JG

Adaptive Remodeling of the Bacterial Proteome by Specific Ribosomal Modification Regulates Pseudomonas Infection and Niche Colonisation.

• DOI: 10.1371/journal.pgen.1005837
• 发表时间: 2016-02
• 期刊: PLoS genetics
• 影响因子: 4.5
• 作者: Little RH;Grenga L;Saalbach G;Howat AM;Pfeilmeier S;Trampari E;Malone JG
• 通讯作者: Malone JG

Structural insights into the mechanism of adaptive ribosomal modification by Pseudomonas RimK.

• DOI: 10.1002/prot.26429
• 发表时间: 2023-03
• 期刊: Proteins
• 影响因子: 2.9

Quick change: post-transcriptional regulation in Pseudomonas.

• DOI: 10.1093/femsle/fnx125
• 发表时间: 2017-08-01
• 期刊: FEMS microbiology letters
• 影响因子: 2.1
• 作者: Grenga L;Little RH;Malone JG
• 通讯作者: Malone JG

Pan-genome analysis identifies intersecting roles for Pseudomonas specialized metabolites in potato pathogen inhibition.

• DOI: 10.7554/elife.71900
• 发表时间: 2021-12-31
• 期刊: eLife
• 影响因子: 7.7
• 作者: Pacheco-Moreno A;Stefanato FL;Ford JJ;Trippel C;Uszkoreit S;Ferrafiat L;Grenga L;Dickens R;Kelly N;Kingdon AD;Ambrosetti L;Nepogodiev SA;Findlay KC;Cheema J;Trick M;Chandra G;Tomalin G;Malone JG;Truman AW
• 通讯作者: Truman AW