Bacillus Subtilis Chaperone/protease Mechanisms In Metabolic Shutdown

枯草芽孢杆菌伴侣/蛋白酶代谢关闭机制

• 批准号: BB/X001415/1
• 负责人: Rivka Isaacson
• 金额: $ 64.92万
• 依托单位: King's College London
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FX001415%2F1
• 关键词: Bacillus; Subtilis; Chaperone; protease; Mechanisms

In many types of bacteria there is a rotary-shredder machine called ClpCP that acts as waste disposal for proteins that are no longer needed. It is built of two parts: ClpC, which is a 6-membered ring that uses energy from ATP hydrolysis to unwind the three dimensional shapes of proteins into a single chain that looks like beads on a wire. This is then fed into ClpP, which takes the form of a stacked pair of 7-membered rings, to be chopped up into small reusable parts. The ClpCP machine is recruited to particular jobs within cells by adaptor proteins. One of these jobs is to destroy many proteins that are important for metabolism, when bacteria form long-lived hardy spores to survive harsh conditions as the spores need to become metabolically inactive. In this study my group will examine a newly discovered protein, MicA, which acts an adaptor to ClpCP during bacterial spore formation. Sporulation is partially responsible for the persistence of 'hospital superbugs' as spores are a long-lived bacterial form, resistant to cleaning agents and thriving in patients depleted of natural gut microflora.We intend to uncover the detailed molecular shapes of MicA when it is bound to ClpCP and substrates using indirect techniques as they are too small to see even using powerful microscopes. We specialise in measuring protein shapes and the way they fit together by producing them artificially in large quantities, with the help of bacteria which act as our 'protein factories'. We then deduce the proteins' molecular structures by processing their behaviour when we bounce X-rays or electrons off them or put them in strong magnetic fields. Each of these techniques has its strengths and weaknesses but our combined approach can yield complementary information filling in the gaps left by using just one of the methods. Collaborating with microbiologists, electron microscopists and chaperone scientists, we will feed information into each others' experiments to build up a mechanistic picture of this important step in bacterial spore formation. For example, if we identify a mutation in one of our proteins that makes it bind more tightly to its partner our collaborator can make the same mutation within bacteria to test whether it has the predicted effect in living systems.By solving this jigsaw puzzle we hope to be in a stronger position to design novel antibiotics to attack the increasing problem of bacterial drug resistance and the project also has longer term implications for understanding metabolism and protein quality control in many aspects of health and disease.

在许多类型的细菌中，都有一种叫做ClpCP的旋转粉碎机，它可以作为不再需要的蛋白质的废物处理器。它由两部分组成：ClpC是一个6元环，它利用ATP水解产生的能量将蛋白质的三维形状展开成一条看起来像金属丝上的珠子的单链。然后将其送入ClpP中，ClpP以堆叠的一对7元环的形式存在，并被切成可重复使用的小部分。ClpCP机器被衔接蛋白招募到细胞内的特定工作。这些工作之一是破坏许多对新陈代谢很重要的蛋白质，当细菌形成长寿的哈代孢子以在恶劣的条件下生存时，孢子需要变得代谢不活跃。在这项研究中，我的团队将研究一种新发现的蛋白质云母，它在细菌孢子形成过程中充当ClpCP的适配器。孢子形成是“医院超级细菌”持续存在的部分原因，因为孢子是一种寿命较长的细菌形式，对清洁剂有抵抗力，并且在天然肠道菌群耗尽的患者中茁壮成长。我们打算使用间接技术揭示云母与ClpCP和底物结合时的详细分子形状，因为它们太小，即使使用强大的显微镜也无法看到。我们专注于测量蛋白质的形状以及它们通过人工大量生产的方式结合在一起的方式，在细菌的帮助下充当我们的“蛋白质工厂”。然后，我们通过处理蛋白质的行为来推断蛋白质的分子结构，当我们将X射线或电子从它们身上反射或将它们置于强磁场中时。这些技术中的每一种都有其优点和缺点，但我们的组合方法可以产生补充信息，填补只使用其中一种方法留下的空白。与微生物学家，电子显微镜和伴侣科学家合作，我们将为彼此的实验提供信息，以建立细菌孢子形成这一重要步骤的机械图。比如说，如果我们在我们的一种蛋白质中发现了一个突变，使它与它的伴侣结合得更紧密，我们的合作者就可以在细菌中进行同样的突变，以测试它是否在生命系统中具有预期的效果。通过解决这个拼图，我们希望能够处于更有利的地位，设计新的抗生素来解决日益严重的细菌耐药性问题，该项目也对以下方面具有长期影响：了解代谢和蛋白质质量控制在健康和疾病的许多方面。