NSF-BSF: Macromolecular crowding in vitro and in cells

蛋白质-蛋白质相互作用调节所有细胞功能，但它们几乎总是在水中进行研究，而不是在细胞内存在的复杂和拥挤的环境中。该项目的结果将填补阻碍新陈代谢完整描述的一个关键空白。将定量生物物理学从简单的解决方案转移到拥挤的环境（包括活细胞内部）的目标是一个重大挑战，但会产生重要成果。所获得的知识将增加对生物学的基本理解，并为生产和稳定蛋白质试剂的努力提供信息。这项工作还将促进本科生和研究生在前沿研究实践中的培训。所有这些努力都是建设美国生物经济的关键。该项目的目标是获得有关拥挤条件下蛋白质和蛋白质复合物稳定性的广泛适用的知识。一个结合了硬相互作用和软相互作用的新模型声称可以解释大分子拥挤对蛋白质和蛋白质复合物稳定性的自由能、熵和熵的影响，该模型将在使用两种类型或拥挤分子的三种蛋白质系统上进行测试。一种系统用于评估蛋白质稳定性。另外两个系统评估简单二聚化和折叠二聚化。两种类型的拥挤分子是工业上重要的合成聚合物和一系列从头设计的蛋白质。本项目将采用19F核磁共振波谱和等温滴定量热法检测系统。这个美国/以色列合作项目得到了美国国家科学基金会和以色列两国科学基金会的支持。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

Protein-protein interactions regulate all cellular functions, yet they are almost always studied in water rather than in the complex and crowded environment that exists inside cells. The results of this project will fill a key gap that prevents a complete description of metabolism. The goal of moving quantitative biophysics from simple solutions to crowded environments, including inside living cells, is a major challenge with important outcomes. The knowledge gained will add to both the fundamental understanding of biology and inform efforts to produce and stabilize protein-based reagents. The work will also facilitate the training of undergraduate and graduate students in the practice of cutting-edge research. All these efforts are key to building the US bioeconomy.The goal of the project is to gain broadly-applicable knowledge about protein- and protein complex- stability under crowded conditions. A new model combining hard and soft interactions claiming to explain macromolecular crowding effects on the free energy, enthalpy and entropy of protein- and protein complex- stability will be tested on three protein systems using two types or crowding molecules. One system is used to assesses protein stability. The other two systems assess simple dimerization and dimerization with folding. The two types of crowding molecules are industrially important synthetic polymers and a series of de novo designed proteins. This project will use detection system of 19F nuclear magnetic resonance spectroscopy and isothermal titration calorimetry. This collaborative US/Israel project is supported by the US National Science Foundation and the Israeli Binational Science Foundation.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.