Investigation into the Evolution of a Protein Enzyme from Random Sequence Origin

智力优势。第一批蛋白酶是如何从原始的随机序列库进化而来的，这仍然是生物学中一个基本的未解之谜。一种可能性是，酶偶然具有某种内在的催化功能，这种功能是通过自然选择优化的。另一种情况是，酶是从最初只结合其底物的蛋白质进化而来的，后来适应于催化与这些底物的反应。为了解决这个问题，该项目将达尔文进化论的原理与X射线晶体学相结合，研究蛋白质进化功能的机制。通过这个过程，发现了一种来自随机序列来源的蛋白质，它催化与它所选择的底物的反应。基于这一观察，推测许多酶可能起源于最初仅结合其底物并随后获得催化与这些底物反应的能力的蛋白质。这可能是随机序列来源的功能酶的第一个例子。研究蛋白质如何进化功能的实用价值在于，这些知识有朝一日可以用于在实验室中创造量身定制的酶。在这方面，该研究项目的方法是理想的，用于评估指定具有所需功能特性的多肽所需的信息量以及改变或改善现有功能所需的要求。本研究的重点是研究合成的非生物蛋白质进化催化功能的进化路径。 更广泛的影响。这项研究有可能通过对分布在蛋白质宇宙中的结构和功能多样性的新见解来提供广泛的科学影响。通过消除许多与生物学相关的内在偏差，PI能够搜索蛋白质序列空间的稀疏区域，以获得给定功能问题的唯一独立解决方案。这种方法导致发现从非生物来源获得的合成蛋白质具有采用具有离散化学功能的新折叠的能力，包括酶催化。在这一领域的持续研究有望通过对描述生物蛋白质进化的模型提出新的限制，提高对生物进化的化学基础的基本理解。这一研究领域还有望揭示在实验室中进化定制酶的新策略，这仍然是化学和合成生物学的一个主要问题。此外，该项目还包含一个重要的教育部分，旨在实施一项积极的大学努力，以吸引和保持学生对物理科学的兴趣，并改善代表性不足的少数群体对数学和科学的参与。作为该项目的一部分，PI计划继续开展协同活动，包括对高中生和本科生进行实验室技术培训，使他们能够解决健康和科学方面的重大问题。通过这项工作，PI与亚利桑那州立大学社会和家庭动态中心的Sandra Replikins博士建立了关系，以帮助了解儿童对科学的价值观。

Intellectual Merit. How the first protein enzymes evolved from a primordial pool of random sequences remains a fundamental unanswered question in biology. One possibility is that enzymes, by chance, had some intrinsic catalytic function that was optimized by natural selection. An alternative scenario is that enzymes evolved from proteins that initially only bound their substrates and later adapted to catalyze reactions with those substrates. To address this question, this project combines the principles of Darwinian evolution with X-ray crystallography to study the mechanism by which proteins evolve function. Through this process, a protein from random sequence origin was discovered that catalyzes a reaction with the substrate for which it was selected. Based on this observation, it was speculated that many enzymes may have originated from proteins that initially only bound their substrates and later acquired the ability to catalyze reactions with those substrates. This may be the first example of a functional enzyme from random sequence origin. The practical value of studying how proteins evolve function is that this knowledge could one day be used to create tailor-made enzymes in the laboratory. In this regard, the approach of this research project is ideal for evaluating the amount of information that is needed to specify a polypeptide with a desired functional property and the requirements needed to change or improve an existing function. The focus of this research is to investigate the evolutionary path by which a synthetic, non-biological protein evolved catalytic function. Broader Impact. This research has the potential to provide broad scientific impact by developing new insight into the diversity of structures and functions distributed across the protein universe. By removing many of the intrinsic biases associated with biology, the PI was able to search sparse regions of protein sequence space for unique independent solutions to a given functional problem. This approach led to the discovery that synthetic proteins obtained from non-biological origins have the ability to adopt novel folds possessing discrete chemical functions, which includes enzyme catalysis. Continued research in this area is expected to improve the fundamental understanding of the chemical basis of biological evolution by developing new constraints on models that describe the evolution of biological proteins. This area of research is also expected to reveal new strategies for evolving tailor-made enzymes in the laboratory, which remains a major problem in chemical and synthetic biology. In addition, this project also contains a significant educational component designed to implement a proactive university effort to attract and maintain student interest in the physical sciences, and improve the participation of underrepresented minorities in math and science. As part of this project, the PI plans to continue synergistic activities that involve training high school and undergraduate students in laboratory techniques that allow them to tackle significant problems in health and science. Through this work, the PI has developed a relationship with Dr. Sandra Simpkins in the Center for Social and Family Dynamics at ASU to help understand the values that children place on science.