Mutually Exclusive Protein Folding

这个项目的目标是开发一种机制，通过这种机制，蛋白质折叠可以与解折叠相结合，从而 在蛋白质和酶中引入变构控制。为此，我们介绍了两种技术： 互斥折叠(MEF)和交替框架折叠(AFF)。MEF使用存储在 一个结构域的折叠结构，在同一分子中展开另一个结构域。这两个域不能 同时以它们的自然状态存在；因此，分子在两种功能形式之间相互转换。通过 将受体结构域与酶或功能结构域相匹配，可以在其中创建新的分子 配体结合可产生所需的生物学功能。AFF是一种新型的偶联结合机制 以一种简单、可预测和定义明确的方式进行构象变化。它涉及氨基的排列 酸序列和部分序列复制。由此产生的蛋白质在天然结构之间切换， 在结构上相似，但具有不同的拓扑。驱动力由万向联动机构提供 在配体结合和蛋白质折叠之间。构象变化被利用到生物功能或 到一个输出信号。AFF可以在单个蛋白质中实现，也可以在两个结构域中与MEF结合 融合以建立变构调节。AIMS将产生钙和糖的生物传感器， 有效的抗HIV毒素，以及一种将条件功能性引入所选蛋白质的方法。这些 分子将为设计具有新的分子识别能力的多种蛋白质建立一个框架 和治疗属性。

The goal of this project is to develop mechanisms by which protein folding can be coupled to unfolding, in order to introduce allosteric control into proteins and enzymes. Two techniques are introduced for this purpose: mutually exclusive folding (MEF) and alternate frame folding (AFF). MEF uses the free energy stored in the folded structure of one domain to unfold another domain within the same molecule. The two domains cannot exist simultaneously in their native states; hence the molecule interconverts between two functional forms. By matching a receptor domain with an enzymatic or functional domain, one can create new molecules in which ligand binding causes a desired biological function. AFF is a novel mechanism for coupling binding to conformational change in a simple, predictable, and well-defined manner. It involves permutation of the amino acid sequence and partial sequence duplication. The resulting protein switches between native structures that are structurally similar, but possess different topologies. The driving force is provided by the universal linkage between ligand binding and protein folding. The conformational change is harnessed to a biological function or to an output signal. AFF can be implemented within a single protein or can be combined with MEF in a twodomain fusion to establish allosteric regulation. The aims will generate biosensors for calcium and sugars, a potent anti-HIV toxin, and a method for introducing conditional functionality to a protein of choice. These molecules will establish a framework for designing a wide variety of proteins with novel molecular recognition and therapeutic properties.