Characterisation of disulfide bond formation in bacterial pathogens: Unravelling the adaptation of a classical pathway into a virulence aid.

细菌病原体中二硫键形成的表征：揭示经典途径对毒力辅助的适应。

• 批准号: MR/M009505/1
• 负责人: Despoina Mavridou
• 金额: $ 107.18万
• 依托单位: Imperial College London
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2015
• 资助国家: 英国
• 起止时间: 2015 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=MR%2FM009505%2F1
• 关键词: Characterisation; disulfide; bond; formation; bacterial

Bacteria are fascinating organisms that are able to adapt to a variety of environmental conditions. However, because of this characteristic, bacterial pathogens are able to quickly evolve to bypass human antibacterial measures. The rapid increase in resistance to antibiotics, combined with the slowing to a trickle of new antibiotics progressing through the pipeline over the past decades, could soon lead to a public health crisis.A major reason for antibiotic resistance development is the fact that current antibiotics target components of the bacterial cell (usually proteins) which are essential for the viability of the microorganism. This creates selective pressure for the survival of bacteria that are resistant to the antibiotic in use. A way to avoid the emergence of 'superbugs' is to try to render pathogenic bacteria harmless by developing compounds that target their weaponry i.e. the molecules that allow bacteria to invade and damage their host. In this context, I am interested in investigating the option of using a central bacterial pathway, which is involved in the assembly of these weapons, against bacterial pathogens.In bacteria, the Disulfide bond (DSB) protein system is responsible for the formation of additional linkages (called disulfide bonds) in proteins which are located outside the main cellular compartment and need to withstand harsh environments. Since the majority of molecules that promote bacterial virulence are protein-based and are also located near the outer surface of the cell, they are dependent on the DSB protein system for correct assembly. Therefore, by studying the DSB proteins of pathogenic bacteria we will eventually be able to use this knowledge for developing new, efficient ways of neutralising bacterial disease-causing organisms without promoting antibiotic resistance.My hypothesis is that in bacterial pathogens the DSB pathway has diversified, compared to organisms that are harmless. This allows pathogenic bacteria to optimise their toolkit for invading the host and evading the host's defence mechanisms. My research project consists of three parts all related to this hypothesis. In the first part, I aim to use bioinformatics to determine all variations of the DSB pathway in pathogens and to identify underlying common traits between DSB protein systems of pathogenic bacteria. This is the first step towards developing novel approaches against bacterial virulence. In the second part of my research project, I will study a pivotal component of the DSB system (a protein called DsbA, which is essential for the assembly of several bacterial weapons) in the human pathogen Neisseria meningitidis, the causative agent of meningitis. In this bacterium there are three copies of DsbA and their function remains unclear. By elucidating their involvement in the pathogenesis of N. meningitidis we can find additional ways to combat this pathogen in the future. The third and final part of my research project will focus on the extremely antibiotic-resistant bacterium Pseudomonas aeruginosa which causes severe problems in post-operational and immunocompromised patients. I plan to study the two copies of the protein DsbD, which are found in this organism and are thought to contribute to its virulence with the scope of contributing to the design of attenuated bacterial strains that could be used for vaccine development.My proposed research aims to acquire fundamental knowledge about the role of a central protein system in bacterial pathogens. This knowledge is key for the development of much-needed new antibacterial strategies which will prevent the emergence of antibiotic resistance in the future.

细菌是一种迷人的生物体，能够适应各种环境条件。然而，由于这种特性，细菌病原体能够迅速进化以绕过人类的抗菌措施。抗生素耐药性的迅速增加，加上过去几十年来新抗生素的研发速度放缓，可能很快导致公共卫生危机。抗生素耐药性发展的一个主要原因是，目前的抗生素针对的是细菌细胞中对微生物生存力至关重要的成分（通常是蛋白质）。这为对使用中的抗生素具有抗性的细菌的生存创造了选择性压力。避免“超级细菌”出现的一种方法是，通过开发针对病原菌武器的化合物，即允许细菌入侵和破坏宿主的分子，试图使病原菌无害。在这种情况下，我感兴趣的是研究使用一个中央细菌途径的选择，这是参与这些武器的组装，对细菌病原体。在细菌中，二硫键（DSB）蛋白质系统负责形成额外的连接（称为二硫键）的蛋白质位于主细胞区室之外，需要承受恶劣的环境。由于大多数促进细菌毒力的分子是基于蛋白质的，并且也位于细胞的外表面附近，因此它们依赖于DSB蛋白系统进行正确组装。因此，通过研究致病菌的DSB蛋白，我们最终将能够利用这些知识来开发新的，有效的方法来中和细菌致病生物体，而不会促进抗生素耐药性。我的假设是，在细菌病原体中，DSB途径已经多样化，与无害的生物体相比。这使得病原菌能够优化它们的工具包，以入侵宿主并逃避宿主的防御机制。我的研究项目包括三个部分，都与这个假设有关。在第一部分中，我的目标是使用生物信息学来确定病原体中DSB途径的所有变化，并确定病原菌的DSB蛋白系统之间的潜在共同特征。这是开发对抗细菌毒力的新方法的第一步。在我的研究项目的第二部分，我将研究DSB系统的一个关键组成部分（一种称为DsbA的蛋白质，它是组装几种细菌武器所必需的）在人类病原体脑膜炎奈瑟氏菌，脑膜炎的病原体。在这种细菌中，有三个DsbA拷贝，它们的功能尚不清楚。通过阐明它们参与N.我们可以在未来找到更多的方法来对抗这种病原体。我的研究项目的第三部分也是最后一部分将集中在极端耐药细菌铜绿假单胞菌，它会导致术后和免疫功能低下患者的严重问题。我计划研究的两个副本的蛋白DsbD，这是发现在这种生物体，并被认为有助于其毒力的范围内，有助于减毒菌株的设计，可用于疫苗的开发。我提出的研究旨在获得基本知识的作用，中央蛋白系统在细菌病原体。这些知识是开发急需的新抗菌策略的关键，这些策略将防止未来抗生素耐药性的出现。

项目成果

Plasma membrane profiling during enterohemorrhagic E. coli infection reveals that the metalloprotease StcE cleaves CD55 from host epithelial surfaces.

肠膜状大肠杆菌感染期间的质膜分析表明，金属蛋白酶STCE从宿主上皮表面裂解CD55。

• DOI: 10.1074/jbc.ra118.005114
• 发表时间: 2018-11-02
• 期刊: The Journal of biological chemistry
• 作者: Furniss RCD;Low WW;Mavridou DAI;Dagley LF;Webb AI;Tate EW;Clements A
• 通讯作者: Clements A

Breaking antimicrobial resistance by disrupting extracytoplasmic protein folding

通过破坏胞质外蛋白折叠来打破抗菌药物耐药性

• DOI: 10.7554/elife.59046
• 发表时间: 2022
• 期刊: eLife
• 影响因子: 7.7
• 作者: Furniss R

Breaking antimicrobial resistance by disrupting extracytoplasmic protein folding.

• DOI: 10.7554/elife.57974
• 发表时间: 2022-01-13
• 期刊: eLife
• 影响因子: 7.7
• 作者: Furniss RCD;Kaderabkova N;Barker D;Bernal P;Maslova E;Antwi AAA;McNeil HE;Pugh HL;Dortet L;Blair JMA;Larrouy-Maumus G;McCarthy RR;Gonzalez D;Mavridou DAI
• 通讯作者: Mavridou DAI

A novel stabilization mechanism for the type VI secretion system sheath.

• DOI: 10.1073/pnas.2008500118
• 发表时间: 2021-02-16
• 期刊: Proceedings of the National Academy of Sciences of the United States of America
• 影响因子: 11.1
• 作者: Bernal P;Furniss RCD;Fecht S;Leung RCY;Spiga L;Mavridou DAI;Filloux A
• 通讯作者: Filloux A

Costs and benefits of provocation in bacterial warfare.

• DOI: 10.1073/pnas.1801028115
• 发表时间: 2018-07-17
• 期刊: Proceedings of the National Academy of Sciences of the United States of America
• 影响因子: 11.1
• 作者: Gonzalez D;Sabnis A;Foster KR;Mavridou DAI
• 通讯作者: Mavridou DAI