NER: Mechanically "Tuning" and "Switching" the Dynamics of Molecular Motors

本提案是根据NSE，NSF 01-157收到的。该研究小组将开发一个广泛适用的概念框架，以描述DNA聚合物上的张力如何产生在DNA聚合酶马达中观察到的“调整”和“切换”现象。这项工作需要开发外力与马达构象动力学相互作用的理论模型。还有必要理解分子的各向异性如何与非平衡化学反应产生的能量结合在一起偏向布朗涨落，以驱动马达朝着更好的方向前进。像任何纳米尺度的设备一样，布朗马达通过应对而不是对抗热噪音而获得巨大的好处。除了构建适当的理论框架并展示其对单分子实验的解释作用外，该团队还希望将从生物马达研究中获得的见解转化为在纳米尺度上执行特定功能的工程马达的设计和控制。这项工作的广泛影响是，它不仅可能为在细胞中控制DNA复制的机制提供新的线索，而且还可能导致控制分子尺度过程和纳米设备功能的新策略。该项目由数学和物理科学局的物理和化学部和工程部的电气和通信系统部联合资助。

This proposal was received in response to NSE, NSF 01-157. The research team will develop a broadly applicable conceptual framework to describe how tension on a DNA polymer can produce both the "tuning" and "switching" phenomena observed in DNA polymerase motors. This work entails developing theoretical models for the interaction of external forces with the conformational dynamics of the motor. It is also necessary to understand how molecular anisotropy in combination with the energy from a non-equilibrium chemical reaction biases Brownian fluctuations to drive the motor in a preferred direction. Like any nanoscale device, Brownian motors derive great benefit by working with rather than against thermal noise.In addition to constructing an appropriate theoretical framework and demonstrating its utility for the interpretation of single molecule experiments, the team hopes to translate insight gained from the study of biological motors to the design and control of engineered motors that perform specific functions at the nanoscale. The broad impact of this work is that it may not only shed new light on the mechanism by which DNA replication is controlled in cells but also lead to novel strategies for controlling molecular scale processes and the function of nanodevices.The project is jointly funded by the Divisions of Physics and Chemistry in the Mathematical and Physical Sciences Directorate and the Division of Electrical and Communications Systems in the Engineering Directorate.