Mechanisms of spore engulfment in C. difficile

艰难梭菌孢子吞噬机制

• 批准号: MR/V032151/1
• 负责人: Paula S Salgado
• 金额: $ 87.42万
• 依托单位: Newcastle University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=MR%2FV032151%2F1
• 关键词: Mechanisms; spore; engulfment; C.; difficile

Clostridioides difficile, commonly known as C. diff, is a bacterium that can cause diarrhoea, often with repeat episodes, and, in more severe cases, death. It is resistant to most commonly used antibiotics and using these drugs creates the conditions for infection to occur, as the normal, health-promoting bacteria in the gut is disrupted. Continued use of antimicrobials leads to new resistant and multi-resistant strains including against several commonly used antibiotics. Intense antibiotic use across the world during the current pandemic has made this risk higher and the search for more species-specific drugs even more important.The life cycle of C. diff involves growth, formation of dormant cells called spores, and germination of the spores when the conditions are favourable. Spores provide C. diff with a formidable capacity to remain in the environment and in the host, offering resistance to radiation, heat and most commonly used cleaning agents. Due to these properties, spores are responsible for transmission of C. diff infections (CDI) and repeat episodes. Highly resistant spores produced by antibiotic-resistant/multi-resistant strains may be one of the most serious challenges we face in terms of control of C. diff. Despite its importance, the exact mechanisms of spore formation are still poorly studied.In this project we propose to combine our expertise to study a key aspect of spore formation. As spores are dormant cells, the potential for antimicrobial resistance to arise is diminished, making this an innovative way to reduce and control CDI to be explored in the future. Spore formation starts with the bacterial cell dividing into a smaller cell - the forespore - and a bigger, mother cell. The forespore is then surrounded by the mother cell in a process called engulfment. We have previously shown that two key protein machineries - the DP and Q:AH - are essential for this process and started revealing some of their key features. In this project we will build upon this work and answer three key questions:1. How is the engulfment machinery organised?We will characterise the interactions between these proteins, their role and their organisation. We will also determine the structures of these proteins to better understand their mode of action. 2. Which forces drive the process?We will investigate what drives engulfment by characterising the composition of the main cell envelope - the peptidoglycan - how it varies and any other proteins involved in the process.3. How does engulfment and sporulation impact disease?We will investigate the role of these machineries in disease using disease, transmission and infection models.This project will enhance our knowledge of a fundamental process in CDI and open new therapeutic avenues to control infection.

艰难梭菌，俗称C。diff是一种可引起腹泻的细菌，经常反复发作，在更严重的情况下，可导致死亡。它对大多数常用的抗生素具有耐药性，使用这些药物会为感染的发生创造条件，因为肠道中正常的促进健康的细菌会被破坏。持续使用抗菌剂导致新的耐药和多重耐药菌株，包括对几种常用抗生素的耐药菌株。在目前的大流行期间，世界各地大量使用抗生素，这使得这种风险更高，寻找更具物种特异性的药物变得更加重要。diff涉及生长、称为孢子的休眠细胞的形成以及在条件有利时孢子的萌发。孢子提供C. diff具有强大的能力，可以保留在环境和主机中，提供抗辐射，耐热和最常用的清洁剂。由于这些特性，孢子负责传播C。不同感染（CDI）和重复发作。由抗虫/多重抗性菌株产生的高抗性孢子可能是控制C. diff.尽管它的重要性，孢子形成的确切机制仍然是很差的研究。在这个项目中，我们建议联合收割机结合我们的专业知识来研究孢子形成的一个关键方面。由于孢子是休眠细胞，因此抗菌素耐药性产生的可能性降低，使其成为未来探索减少和控制CDI的创新方法。孢子的形成始于细菌细胞分裂成一个较小的细胞-前孢子-和一个较大的母细胞。然后，前孢子被母细胞包围，这一过程称为吞噬。我们之前已经表明，两个关键的蛋白质机器-DP和Q：AH -是这个过程中必不可少的，并开始揭示他们的一些关键特征。在这个项目中，我们将建立在这项工作，并回答三个关键问题：1。吞噬机器是如何组织的？我们将讨论这些蛋白质之间的相互作用，它们的作用和它们的组织。我们还将确定这些蛋白质的结构，以更好地了解它们的作用模式。2.是哪些力量推动了这一进程？我们将通过描述主要细胞包膜的组成-肽聚糖-它如何变化以及参与该过程的任何其他蛋白质来研究是什么驱动了吞噬。吞噬和孢子形成如何影响疾病？我们将使用疾病、传播和感染模型来研究这些机制在疾病中的作用。该项目将增强我们对CDI基本过程的了解，并开辟新的治疗途径来控制感染。

项目成果

Structure and assembly of the S-layer in C. difficile.

• DOI: 10.1038/s41467-022-28196-w
• 发表时间: 2022-02-25
• 期刊: Nature communications
• 影响因子: 16.6
• 作者: Lanzoni-Mangutchi P;Banerji O;Wilson J;Barwinska-Sendra A;Kirk JA;Vaz F;O'Beirne S;Baslé A;El Omari K;Wagner A;Fairweather NF;Douce GR;Bullough PA;Fagan RP;Salgado PS
• 通讯作者: Salgado PS

An ancient metalloenzyme evolves through metal preference modulation.

• DOI: 10.1038/s41559-023-02012-0
• 发表时间: 2023-05
• 期刊: Nature ecology & evolution
• 影响因子: 16.8

An intact S-layer is advantageous to Clostridioides difficile within the host.

• DOI: 10.1371/journal.ppat.1011015
• 发表时间: 2023-06
• 期刊: PLoS pathogens
• 影响因子: 6.7