Studying the structure and function of a novel family of bacterial copper storage proteins

研究细菌铜储存蛋白新家族的结构和功能

• 批准号: 2144124
• 金额: --
• 依托单位: Newcastle University
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2144124
• 关键词: Studying; structure; function; novel; family

Copper is an essential metal ion for most organisms, acting as a cofactor for key enzymes. However, copper can also have toxic effects on cells, and mechanisms have evolved for its safe handling. We have discovered a new family of proteins that allow bacteria to safely store copper (Nature 2015, 525, 140-143). These proteins (the Csps) were identified in methane-oxidising bacteria (methanotrophs), where they store copper for the main enzyme that oxidises methane, a potent greenhouse gas. Csp homologues are widespread in methanotrophs and a range of other bacteria, including important pathogens. As copper is thought to be used by hosts to attack invading pathogens, the presence of a protein that can defend by soaking up large quantities of copper ions could be key for virulence. A better understanding of the role of Csps in copper handling by bacteria is clearly required, which will be achieve using a range of in vitro and in vivo approaches. This work can be carried out in methanotrophs, pathogens, or the widely used model organism Bacillus subtilis. Methanotrophs, such as Methylosinus trichosporium OB3b in which the Csps were originally discovered, can possess a cytosolic Csp3 and an exported Csp1. The latter has been shown to store Cu(I) for the almost ubiquitous membrane-bound particulate methane monooxygenase (pMMO). Both of these Csps from M. trichosporium OB3b have been characterised in vitro (Nature 2015, 525, 140-143; Sci. Rep. 2016, 6:39065) and display striking differences in terms of how Cu(I) binds (Angew. Chem. Int. Ed. Engl. 2017, 56, 8697-8700) and the rate of Cu(I) removal. Understanding the structural features that are responsible for these differences and their influence on copper storage and removal within the methanotroph will be studied.Pathogens such as Neisseria gonorrhoeae, Salmonella enterica sv. Typhimurium, Pseudomonas aeruginosa, and the Burkholderia cepacia complex can possess either a Csp1 or Csp3. Analysing the in vitro properties of these Csps and their potential role in pathogenicity is another area in which studies can be undertaken. An appealing possibility is to compare Csp3s from P. aeruginosa strains and Csp1s from the B. cepacia complex. Both of these opportunistic pathogens can develop multi-drug resistance and are a major concern for patients with cystic fibrosis. Understanding the role of the Csps in these organisms and their potential influence on pathogenesis could help in developing new antimicrobials.

铜是大多数生物体必需的金属离子，是关键酶的辅因子。然而，铜也会对细胞产生毒性影响，而且已经进化出了安全处理铜的机制。我们发现了一个新的蛋白质家族，使细菌能够安全地储存铜(自然2015,525,140-143)。这些蛋白质(CSP)是在甲烷氧化细菌(甲烷营养细菌)中发现的，它们在那里储存铜，用于氧化甲烷的主要酶，甲烷是一种强有力的温室气体。CSP同系物广泛存在于甲烷氧化菌和包括重要病原体在内的一系列其他细菌中。由于铜被认为被宿主用来攻击入侵的病原体，一种可以通过吸收大量铜离子来防御的蛋白质的存在可能是毒力的关键。显然，需要更好地了解CSPs在细菌处理铜过程中的作用，这将通过一系列体外和体内方法来实现。这项工作可以在甲烷氧化菌、病原体或广泛使用的模式生物枯草芽孢杆菌中进行。甲烷氧化菌，如最初发现CSPs的甲氧西林天花粉OB3b，可以拥有胞质Csp3和输出Csp1。后者被证明为几乎无处不在的膜结合颗粒甲烷单加氧酶(PMMO)存储铜(I)。这两个CSP都来自Trichosporium OB3b，已经在体外进行了表征(Nature 2015,525,140-143；Sci.2016年，6：39065)，并在铜(I)如何结合方面显示出显著的差异(Angew.化学。内部艾德恩格尔2017，56,8697-8700)和铜(I)的去除速率。了解造成这些差异的结构特征及其对甲烷菌内铜储存和清除的影响将被研究。病原体，如淋球菌，肠沙门氏菌SV。鼠伤寒杆菌、铜绿假单胞菌和洋葱伯克霍尔德氏菌复合体可以具有Csp1或Csp3。分析这些CSP的体外特性及其在致病性中的潜在作用是另一个可以进行研究的领域。一个吸引人的可能性是比较来自铜绿假单胞菌菌株的Csp3和来自洋葱杆菌复合体的Csp1。这两种机会性病原体都会产生多药耐药性，是囊性纤维化患者的主要担忧。了解CSPs在这些微生物中的作用及其对发病机制的潜在影响有助于开发新的抗菌药。