21ENGBIO - Peptide excision, replacement and ligation (PERL) as a new strategy for protein engineering

在这个项目中，我们将开发一种全新的方法来重新设计蛋白质的基本结构。蛋白质工程是生产生物药物、研究活细胞过程和合成复杂材料的一种广泛使用的方法。蛋白质是由氨基酸的长聚合物组成的，这些聚合物折叠起来形成复杂的三维形状。目前可以进行的大多数更改都是对这些粒子表面进行简单的添加。打个比方，这些就相当于给一辆汽车重新喷漆或添加新的轮胎轮箍。蛋白质的形状和结构可以通过在蛋白质首次制造之前(有效地在它出厂之前)进行编辑来进行更大的改变，但最终这些修改必须使用与原始蛋白质相同的材料，因此目前根本无法进行一些修改。目前不可能做的是一旦蛋白质被制造出来就对其进行大的修改；去除完成的折叠蛋白质的一个成分，并用一个新的部分取代它，同时保留一个功能蛋白质。在这个项目中，我们正寻求做到这一点：我们将开发方法来实现将汽车变成敞篷车或关闭引擎的分子等价物！基于我们实验室最近开发的一些重新连接蛋白质部分的技术，我们将开发一种方法，最终允许我们移除一部分蛋白质，并将其替换为由不同材料制成的替代部分，这些部分无法使用细胞的机械插入。

In this project, we will develop a completely new way to re-engineer the basic structure of proteins. Engineering of proteins is a widely-used approach for the production of biopharmaceuticals, for the study of processes in the living cell and for the synthesis of complex materials. Proteins are formed of long polymers of amino-acids which fold up to form complex three-dimensional shapes. The majority of changes that can currently be made are simple additions to the surface of these particles. To use an analogy, these are the molecular equivalent of repainting a car or adding new tire rims. Larger changes to the shape and structure of the protein can be made by editing the protein before it is first made (effectively before it leaves the factory) but ultimately these modifications must be made of the same materials as the original protein and so some modifications are simply inaccessible at the moment.What it is not currently possible to do is to make large modifications to the protein once it has been made; to remove an element of the finished, folded protein and replace it with a new part while retaining a functional protein. In this project, we are seeking to do just that: we will develop methods to carry out the molecular equivalent of turning a car into a convertible or switching out the engine! Based on some recently developed technology in our laboratory to rejoin the protein parts, we will develop a method that will ultimately allow us to remove a part of the protein and replace it with alternative parts made from different materials that cannot be inserted using the machinery of the cell.