Probing natural amyloid fibril assembly by protein display

通过蛋白质展示探测天然淀粉样原纤维组装

• 批准号: BB/D019109/1
• 负责人: Paul Barker
• 金额: $ 41.76万
• 依托单位: University of Cambridge
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2007
• 资助国家: 英国
• 起止时间: 2007 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FD019109%2F1
• 关键词: Probing; natural; amyloid; fibril; assembly

The structure and substance of living things are made from self-assembling molecules, primarily proteins. Protein aggregates have become notorious for being associated with some diseases of old age such as Alzheimer's and Parkinson's Diseases. In these disorders, proteins mis-fold and aggregate into large rope-like deposits known as amyloid fibrils. It turns out that most if not all proteins can fold to form these amyloid filaments. The fibrils have a very regular structure and some remarkable physical properties. It turns out that Nature has evolved some proteins to be in this state deliberately, to make fibrils on bacterial cell surfaces, to help bacteria stick to other cells. These are some of the most stable fibrils of their type. The regular and stable structure of amyloid fibrils makes them a good scaffold on which to hang other, functional proteins, and that is this basis of this proposal. We will use the proteins that form the natural amyloid fibrils on bacterial cells and fuse them, at the level of their genes, to other proteins and enzymes. To do this, we need to understand more about how individual proteins, which are about 2 nanometres in all dimensions, assemble to form fibrils that are 10 nanometres wide and 10 micrometres long. We can alter the protein's sequence and observe how the fibrils change. Once we have established more about how the building blocks are assembled, we will fuse other proteins to the building blocks so that their function becomes displayed on the fibrils. To start with we will display proteins that carry electrons around in cells. This way we can make a conducting amyloid fibril. We will also display on the fibrils enzymes that destroy antibiotics. This can be used to protect the cell against an antibiotic, giving the cell an advantage. This property can be used to evolve the fibrils to be more useful technologically. Once we have established the best type of fibril and protein display methods, we can then make fibrils at will and use them to build up networks of fibrils on the nanometre scale. This is a new approach to building molecular devices for electronics and diagnostics, out of completely self-assembling molecules. So while amyloid is a serious problem in many disease states, it may also be remarkably useful for making molecular circuits.

生物的结构和物质是由自组装分子组成的，主要是蛋白质。蛋白质聚集体因与阿尔茨海默氏症和帕金森氏症等一些老年疾病有关而臭名昭著。在这些疾病中，蛋白质错误折叠并聚集成大的绳状沉积，称为淀粉样纤维。事实证明，大多数蛋白质(如果不是全部的话)都可以折叠形成这些淀粉样丝。纤维具有非常规则的结构和一些显著的物理性能。事实证明，大自然进化出了一些蛋白质，故意使其处于这种状态，以便在细菌细胞表面形成纤维，帮助细菌附着在其他细胞上。这些是同类纤维中最稳定的一些。淀粉样蛋白纤维规则而稳定的结构使其成为悬挂其他功能蛋白的良好支架，这就是这一提议的基础。我们将使用在细菌细胞上形成天然淀粉样纤维的蛋白质，并在它们的基因水平上将它们与其他蛋白质和酶融合。要做到这一点，我们需要更多地了解单个蛋白质是如何组装成10纳米宽10微米长的纤维的。我们可以改变蛋白质的序列，观察纤维是如何变化的。一旦我们确定了更多关于构建块是如何组装的，我们将把其他蛋白质融合到构建块上，这样它们的功能就可以在纤维上显示出来。首先，我们将展示在细胞中携带电子的蛋白质。这样我们就可以形成一种导电的淀粉样原纤维。我们还将在纤维上展示破坏抗生素的酶。这可以用来保护细胞免受抗生素的伤害，从而使细胞具有优势。这一特性可以用来进化纤维，使其在技术上更加有用。一旦我们建立了最好的纤维和蛋白质展示方法，我们就可以随意制造纤维，并用它们在纳米尺度上建立纤维网络。这是一种利用完全自组装的分子制造电子学和诊断学分子设备的新方法。因此，虽然淀粉样蛋白在许多疾病状态下都是一个严重的问题，但它在制造分子电路方面也可能非常有用。