Radiation and Dehydration Resistance of Proteins

这项研究将确定单个蛋白质对辐射和脱水的抵抗力，以了解这些特性如何在分子水平上演变，并为设计抗辐射和脱水蛋白质提供长期指导。 辐射和脱水都是破坏生物系统的力量。 它们彼此相关，因为它们都诱导产生自由基，这是极具破坏性的化学物质。 了解蛋白质是如何进化以抵抗自由基损伤的，有助于从根本上了解蛋白质的性质和能力，并对食品生产、生物工程、生物修复和绿色化学产生潜在的长期影响。 开展这项研究将导致本科生和研究生，以及博士后研究人员，在广泛的生物物理技术和定量分析方法的培训。 该项目还包括开发新的科学推广和公众参与活动，包括为普通观众设计的教育性表演和演讲，旨在在极端环境条件下传播生物化学科学。该项目专门研究了一套来自耐辐射异常球菌的DNA结合蛋白，并与大肠杆菌的同源蛋白进行了直接比较。 D.耐辐射菌是地球上最具抗辐射能力的生物之一，在比杀死人类或E.杆菌 通过直接检查来自这种抗辐射生物体的辐射分离蛋白质的功能和稳定性，以及来自辐射敏感生物体的等同同源蛋白质，该项目将回答内在抗辐射性是否是一种可进化的蛋白质特性的问题，就像一些蛋白质进化成耐热，耐酸或耐盐一样。 将在增加暴露于辐射、UV光和脱水下检查配对蛋白质对它们的DNA结合亲和力、蛋白质折叠和稳定性、酶活性和抗氧化剂亲和力的差异影响。 因为这个项目研究蛋白质的功能和稳定性，它不只是询问辐射诱导的自由基是否比其他蛋白质更不经常损伤某些蛋白质，它询问某些蛋白质的主要生理活动（即重要的功能部分）是否比其他蛋白质更不容易受到辐射损伤，以及这种差异是如何产生的。

This research will determine the resistance of individual proteins to radiation and dehydration, in order to understand how these properties evolve at the molecular level, and to provide long-range guidance for designing radiation and dehydration resistance into proteins. Radiation and dehydration are both forces that damage biological systems. They are related to each other because both induce the production of free radicals, which are extremely destructive chemical species. Understanding how proteins may have evolved to resist free radical damage adds to the fundamental understanding of the spectrum of protein properties and capabilities, and has potential long-range impacts for food production, bioengineering, bioremediation, and green chemistry. Conduct of this research will result in the training of undergraduate and graduate students, as well as postdoctoral researchers, in a broad array of biophysical techniques and quantitative analytical methods. This project also includes development of novel science outreach and public engagement activities, including educational based performances and presentations for general audiences that are designed to communicate the science of biochemistry under extreme environmental conditions.This project specifically examines a suite of DNA binding proteins from the bacterium Deinococcus radiodurans in direct comparison with the homologous proteins from Escherichia coli. D. radiodurans is one of the most radiation resistant organisms on Earth, surviving radiation doses 2,000 times greater than those that would kill humans or E. coli. By directly examining the function and stability of the irradiated isolated proteins from this radiation resistant organism alongside the equivalent, homologous proteins from a radiation sensitive organism, the project will answer the question of whether intrinsic radiation resistance is an evolvable protein property in the same way that some proteins have evolved to be heat resistant, acid resistant, or salt resistant. The paired proteins will be examined under increasing exposure to radiation, UV light, and dehydration for differential effects on their DNA binding affinity, protein folding and stability, enzymatic activity, and affinity for antioxidants. Because this project examines protein function and stability, it does not simply ask if radiation induced free radicals damage some proteins less frequently than others, it asks if the primary physiological activities (i.e. the important functional parts) of some species of proteins are less susceptible to radiation damage than others, and how that difference originates.