Molecular Mimics of Protein Tertiary Folding from Primary Sequence Information

项目摘要 蛋白质是维持生命的核心功能工具， 蛋白质模拟对化学家来说是一个巨大的挑战。具有明确折叠倾向的人造骨架， 被称为“折叠体”，可以提供天然实体的生物稳定类似物;然而，与设计有关的挑战 为模仿复杂的三级褶皱创造了障碍。克服这一障碍有望开辟一个新的领域 并将折叠体推向蛋白质功能的多样性。 在最初奖项的支持下，创建折叠体三级结构的一般方法是 基于天然序列中骨架共价结构的系统性改变而开发。一个 在建立这些模拟物复制和调节功能性细胞的能力方面仍然存在重要的差距。 它们所基于的原型蛋白质的性质。PI研究计划的长期目标是 发展出能够复制完整蛋白质的人造骨架的设计原则 并应用这些原理来控制诸如折叠结构的性质， 折叠稳定性、生理稳定性和动力学。本次更新申请的总体目标是 证明了异质骨架折叠体三级结构中可能的功能范围 拟态指导这项工作的核心假设是在最初的奖项中制定的设计原则 周期可用于生产不同原型蛋白质的功能类似物，也可用于调节 天然骨架的功能特征。进行拟议研究的理由是， 在蛋白质启发的人工支架中，将结构模仿推向功能模仿将磨练 设计原理，创造有价值的生物活性剂，并揭示自然系统的新光。 为了检验上述中心假设，将追求两个具体目标：（1）开发模仿 具有天然样分子识别特征的锌指蛋白;（2）创建富含二硫化物的模拟物 昆虫和爬行动物的毒液 就预期成果而言，拟议工作将（1）扩大第三代折叠机的范围 结构模拟（复杂的链拓扑结构，大型多结构域蛋白质）;（2）拓宽功能 这些支架的所有组成部分（DNA、蛋白质和生物膜的选择性识别）;（3）产量 对锌指蛋白序列特异性DNA结合动力学的新认识;和（4）提供了一个 生物活性剂在慢性疼痛管理中具有潜在应用的起点， 治疗微生物感染。总的来说，项目目标的实现将导致垂直 在合成蛋白质模拟物的大小、结构复杂性和功能多样性方面的进展。

PROJECT SUMMARY Proteins are the central functional instruments that enable life, and the development of strategies for protein mimicry is a grand challenge for chemists. Artificial backbones with defined folding propensities, termed “foldamers”, can offer biostable analogues of natural entities; however, challenges related to design create barriers to mimicking complex tertiary folds. Overcoming this barrier promises to open a new frontier and advance foldamers toward the functional versatility of proteins. With support from the initial award, a general method for creating foldamer tertiary structure was developed based on the systematic alteration of backbone covalent structure in natural sequences. An important gap remains in establishing the ability of these mimetics to reproduce and modulate functional properties of prototype proteins on which they are based. A long-term goal of the PI’s research program is to develop principles for the design of artificial backbones capable of reproducing the full panoply of protein folds and functions in nature and to apply these principles to control properties such as folded structure, folded stability, physiological stability, and dynamics. The overall objective of this renewal application is to demonstrate the scope of functions possible in heterogeneous-backbone foldamer tertiary structure mimetics. The central hypothesis guiding this work is that design principles developed in the initial award period can be applied to produce functional analogues of diverse prototype proteins and also used to tune functional characteristics of the native backbone. The rationale for pursuing the proposed research is that pushing beyond structural mimicry to functional mimicry in protein-inspired artificial scaffolds will hone design principles, create valuable bioactive agents, and shed new light on natural systems. In order to test the above central hypothesis, two specific aims will be pursued: (1) develop mimics of zinc finger proteins with native-like molecular recognition characteristics; (2) create mimics of disulfide-rich domains from insect and reptile venoms. In terms of expected outcomes, the proposed work will (1) expand the scope of foldamer tertiary structure mimicry (complex chain topologies, large multidomain proteins); (2) broaden the functional repertoire of these scaffolds (selective recognition of DNA, proteins, and biological membranes); (3) yield new insights into the dynamics of sequence-specific DNA binding by zinc finger proteins; and (4) provide a starting point toward bioactive agents with potential applications in the management of chronic pain and treatment of microbial infections. Collectively, realization of the goals of the project will lead to a vertical advance in the size, structural complexity, and functional diversity possible in synthetic protein mimetics.