Peptide aptamer optical protein detection

我们的身体由数以万亿计的细胞组成，这些细胞含有数十亿种蛋白质。蛋白质是细胞的主力，除非我们了解它们是如何共同工作的，否则我们将无法在每个细胞水平上理解生命，也无法识别在引发疾病时发生的变化。虽然人类基因组的测序为我们提供了这些蛋白质的目录，但我们仍然缺乏工具来单独研究它们--蛋白质X在这个细胞中表达吗？--以及共同研究--在细胞中表达的蛋白质X和Y真的相互作用吗？这类研究有两个主要障碍。首先，我们需要每种蛋白质的探针，使我们即使在细胞提取液中存在数十亿其他蛋白质分子的情况下也能检测到给定的蛋白质。第二，我们需要一种方法来感知目标蛋白质何时与其特定的探针结合--蛋白质如此之小，以至于它们产生的任何信号都是微小的。解决这一问题的一种方法是在能够产生非常大信号的蛋白质上添加标签，但这种解决方案也有自己的问题，因为标签可以改变蛋白质的行为，例如防止具有生物意义的结合事件，或者创建新的、不相关的相互作用。我们已经解决了这两个问题，一种是使用一种名为蛋白质工程的技术来创造出专门识别目标蛋白质的人造蛋白质，另一种是足够坚固的人造蛋白质，这些蛋白质可以附着在传感表面上，产生无标记的电或光信号。我们对分子荧光和纳米尺度结构的光学性质的理解的最新进展为敏感感觉界面的产生提供了很大的帮助。该项目的目标是将可接受的人工蛋白质与这些界面相结合，并确定将我们的概念验证工作应用于产生检测方法的最佳手段，该方法既符合研究人员的需求，也使目前无法回答的问题得到回答。这些问题从询问在单个细胞中可以检测到的最小蛋白质拷贝数，到使用大多数生物/临床实验室负担得起的技术可以同时检测到的最大不同蛋白质拷贝数，不一而足。

Our bodies are made up of trillions of cells, which contain billions of proteins. Proteins are the workhorses of a cell, and until we understand how they work together, we will not be able to understand life at the level of each cell, nor will we be able to identify the changes that occur in triggering a disease. While the sequencing of the human genome has given us a catalogue of these proteins, we still lack the tools that allow us to study them both individually- is protein X expressed in this cell?- and collectively- do proteins X and Y, which are both expressed in a cell, actually interact with each other? There are two major hurdles to such studies. The first is that we need probes for each protein that allow us to detect a given protein even in the presence of the billions of other protein molecules in a cell extract. The second is that we need a way to sense when a target protein has bound to its specific probe- proteins are so small that any signal they generate is minute. One way around this has been to add labels to proteins that are capable of generating very large signals, but this solution has its own problems, as the label can modify the behaviour of the protein, for example to prevent a biologically-significant binding event, or to create a new, irrelevant interaction. We have solved both problems using a technique called protein engineering to create artificial proteins that specifically recognise target proteins, and that are sufficiently robust that they can be attached to sensing surfaces to generate label-free electrical or optical signals. Recent advances in our understanding of molecular fluorescence and the optical properties of nanometre-scale structures offer much in the generation of sensitive sensory interfaces. The goal of this project is to integrate receptive artificial proteins with these interfaces and identify the best means of applying our proof-of-concept work to the generation of detection methods both compatible with the needs of researchers but also enabling currently unanswerable questions to be answered. Such questions range from asking what is the smallest number of copies of protein that can be detected in a single cell, to what is the largest number of different proteins that can be detected simultaneously using a technology that is affordable to most biological/clinical labs.