EspO orthologs and NleF: type III secretion system effectors of enteric pathogens that modulate apoptosis and inflammation

EspO直系同源物和NleF：调节细胞凋亡和炎症的肠道病原体的III型分泌系统效应子

• 批准号: MR/K019007/1
• 负责人: Gad Frankel
• 金额: $ 181.24万
• 依托单位: Imperial College London
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2013
• 资助国家: 英国
• 起止时间: 2013 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=MR%2FK019007%2F1
• 关键词: EspO; orthologs; NleF; type; III

Escherichia coli is a bacterium that often inhabits the intestines of warm-blooded animals. Subsets of E. coli have evolved the ability to cause disease. One such group are enterohaemorrhagic E. coli (EHEC), which can cause bloody diarrhoea in humans. Infections can involve life-threatening complications affecting the kidneys and are frequently acquired via the food chain. Enteropathogenic E. coli (EPEC) strains are a related subset of bacteria that cause acute watery diarrhoea in infants in the developing world. Shigella strains, which are closely related to E. coli, cause bacillary dysentery (aka Shigellosis). Shigellosis, which is usually acquired by ingestion of contaminated food or water, remains a global endemic disease responsible for ca. 165 million cases of severe dysentery and 1 million deaths annually, particularly in children less than five years of age. Non-typhoidal Salmonella enterica (NTS) strains cause an estimated 1 billion cases of self-limiting foodborne gastroenteritis annually. More recently, multiple antibiotic-resistant strains have emerged as important causes of fatal invasive bacteraemia, particularly in sub-Saharan regions. Importantly, although considered high priority, no vaccines are yet available for either of these pathogens, the development of which relies on better understanding of their biology and infection strategies.EPEC, EHEC, Shigella and Salmonella rely on a 'molecular syringe' to colonise the intestines and produce disease. This syringe serves to inject a set of bacterial proteins termed effectors into cells lining the intestines. This process, known as Type III secretion (T3S), enables the bacteria to take control of processes inside host cells for their own benefit. Our research has shown that T3S is vital for adherence of EHEC and EPEC to the gut lining and to interfere with the induction of host responses that might otherwise resolve the infection. Infected hosts fight bacterial infection by mounting immune responses while infected cells might assist in clearing the pathogen by undergoing programme cell death (aka apoptosis). Importantly, low-level inflammation may assist the pathogens in establishing a foothold within the host as it modulates the gut physiology and the normal gut flora. It is therefore not surprising that the pathogenic E. coli, Shigella and Salmonella inject T3S effector proteins that subvert both inflammation and apoptosis. We recently found that the EPEC and EHEC T3SS effector NleF binds a host cell protein called caspase-4, which plays a role in both apoptosis and inflammation. Similarly, we found the effector EspO of EHEC, and it's family members in Shigella (OspE) and Salmonella (SopO) bind a host cell protein called Hax-1, which is a major inhibitor of apoptosis and has an indirect role in host immune responses. The broad aim of this work is to characterise the mechanism of action and to understand the role during infection of the EspO family members and NleF. In particular, our aim (which is also our strength) is to translate results obtained by biochemical and cell biology assays in vitro to pathogen-host interactions in vivo. The specific aims include: 1. Determine the structure of the EspO:Hax-1 and NleF:caspase-4 complexes 2. Determine the intracellular interactome of EspO family members and NleF3. Dissect the EspO family members and NleF cell signalling pathways using cell culture models4. Study the role of EspO, SopO and NleF and their host cell partner proteins in pathogen-host interaction in animal models in vivo

大肠杆菌是一种经常居住在温血动物的肠道的细菌。大肠杆菌的子集已经发展出引起疾病的能力。这样的群体是肠内大肠杆菌（EHEC），可能会导致人类血腥的腹泻。感染可能涉及影响肾脏的生命并发症，并经常通过食物链获得。肠病大肠杆菌（EPEC）菌株是一个相关的细菌子集，在发展中国家的婴儿中引起急性水性腹泻。与大肠杆菌密切相关的志贺氏菌菌株会引起芽孢杆菌痢疾（又名Shigellosis）。通常通过摄入受污染的食物或水来获得的志菌病仍然是一种全球特有疾病。每年有1.65亿例严重痢疾和100万人死亡，尤其是在五岁以下的儿童中。肠道肠新闻（NTS）菌株每年估计有10亿例自限制的粮食胃肠炎。最近，多种抗生素菌株已成为致命侵入性菌血症的重要原因，尤其是在撒哈拉以南地区。重要的是，尽管认为这两种病原体中的任何一种疫苗都尚无疫苗，但其发展依赖于对其生物学和感染策略的更好理解。EPEC，EHEC，Shigella和Salmonella依赖于“分子突Isringe”来殖民肠道并产生疾病。该注射器可将一组称为效应子的细菌蛋白注入肠内的细胞。该过程被称为III型分泌（T3S），使细菌能够控制宿主细胞内部的过程，以便自身。我们的研究表明，T3S对于EHEC和EPEC遵守肠道衬里至关重要，并干扰可能解决感染的宿主反应的诱导。受感染的宿主通过安装免疫反应来打击细菌感染，而感染细胞可能通过经历程序细胞死亡（又称凋亡）来帮助清除病原体。重要的是，低水平的炎症可能有助于病原体在调节肠道生理学和正常肠道菌群时在宿主内建立立足点。因此，毫不奇怪的是，致病性大肠杆菌，志贺氏菌和沙门氏菌的T3S效应蛋白会颠覆炎症和凋亡。我们最近发现，EPEC和EHEC T3SS效应子NLEF结合了一种称为caspase-4的宿主细胞蛋白，该蛋白在凋亡和炎症中起作用。同样，我们发现了EHEC的效应子ESPO，它是Shigella（OSPE）和沙门氏菌（SOPO）的家庭成员，结合了一种称为HAX-1的宿主细胞蛋白，该宿主细胞蛋白是凋亡的主要抑制剂，在宿主免疫反应中具有间接作用。这项工作的广泛目的是表征作用机理，并了解ESPO家族成员和NLEF感染过程中的作用。特别是，我们的目的（这也是我们的力量）是翻译通过体外生化和细胞生物学测定获得的结果，以便在体内与病原体宿主相互作用。具体目的包括：1。确定ESPO的结构：HAX-1和NLEF：caspase-4复合物2。确定ESPO家族成员和NLEF3的细胞内相互作用组。使用细胞培养模型解剖ESPO家族成员和NLEF细胞信号通路4。研究ESPO，SOPO和NLEF及其宿主细胞伴侣蛋白在体内动物模型中病原体宿主相互作用中的作用

项目成果

The type III secretion system effector EspO of enterohaemorrhagic Escherichia coli inhibits apoptosis through an interaction with HAX-1.

• DOI: 10.1111/cmi.13366
• 发表时间: 2021-09
• 期刊: Cellular microbiology
• 影响因子: 3.4
• 作者: Chatterjee S;Lekmeechai S;Constantinou N;Grzybowska EA;Kozik Z;Choudhary JS;Berger CN;Frankel G;Clements A
• 通讯作者: Clements A

Model of Host-Pathogen Interaction Dynamics Links In Vivo Optical Imaging and Immune Responses.

• DOI: 10.1128/iai.00606-16
• 发表时间: 2017-01
• 期刊: Infection and immunity
• 影响因子: 3.1
• 作者: Ale A;Crepin VF;Collins JW;Constantinou N;Habibzay M;Babtie AC;Frankel G;Stumpf MPH
• 通讯作者: Stumpf MPH

Bacterial virulence factor inhibits caspase-4/11 activation in intestinal epithelial cells.

• DOI: 10.1038/mi.2016.77
• 发表时间: 2017-05
• 期刊: Mucosal immunology
• 影响因子: 8

Enterohaemorrhagic E. coli modulates an ARF6:Rab35 signaling axis to prevent recycling endosome maturation during infection.

• DOI: 10.1016/j.jmb.2016.05.023
• 发表时间: 2016-08-28
• 期刊: JOURNAL OF MOLECULAR BIOLOGY
• 影响因子: 5.6
• 作者: Furniss, R. Christopher D.;Slater, Sabrina;Frankel, Gad;Clements, Abigail
• 通讯作者: Clements, Abigail

The Type III Secretion System Effector SptP of Salmonella enterica Serovar Typhi.

• DOI: 10.1128/jb.00647-16
• 发表时间: 2017-02-15
• 期刊: Journal of bacteriology
• 影响因子: 3.2
• 作者: Johnson R;Byrne A;Berger CN;Klemm E;Crepin VF;Dougan G;Frankel G
• 通讯作者: Frankel G