Collaborative Research: Dynamics of Circular Macromolecules (DNA): From Single Molecules to Highly Entangled States

合作研究：圆形大分子（DNA）动力学：从单分子到高度纠缠态

• 批准号: 1603943
• 负责人: Gregory McKenna
• 金额: $ 17.37万
• 依托单位: Texas Tech University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1603943&HistoricalAwards=false
• 关键词: Collaborative; Research; Dynamics; Circular; Macromolecules

PI: McKenna, Gregory B. / Schroeder, Charles / Anderson, RaeProposal Number: 1603943/ 1604038 / 1603925 The goal of this proposal is to explore the behavior of polymer molecules that form large rings, instead of the usual linear polymer molecules. Such polymers, an example of which can be the DNA molecule, behave in a different way than linear molecules when processed or when they flow in a solution, because there are no ends in the chains. Results of this work can lead to improved polymer materials, to understanding in detail the behavior of bio-molecules, and to new technologies for DNA sequencing. Circular polymers are fascinating materials that have inspired polymer theorists and experimentalists for decades. The dynamics of circular chains differ fundamentally from their linear counterparts due to the absence of chain ends. Despite recent progress, however, the effects of circular topology on polymer dynamics remain a key unresolved problem in the field. In this proposal, the PIs are poised to make major progress in our understanding by preparing circular and linear DNA molecules that are monodisperse and of high topological purity. The assembled team has the expertise to synthesize and characterize circular and linear DNA, and will study the rheological behavior of these materials over a wider range of concentrations and molecular weights than previously achieved. A comprehensive approach is proposed that will include macroscopic and micro-rheology, single molecule polymer dynamics, and DNA synthesis, to provide new information regarding the dynamics of linear and circular DNA. Beyond providing a point of departure for understanding their circular counterparts, the parallel study of linear entangled DNA will provide unprecedented data using perfectly monodisperse DNA samples to directly test predictions from reptation theory, such as the cross-over to reptative behavior at extremely high entanglement densities. In addition to graduate student participation, educational activities are proposed in all three collaborating institutions, ranging from underrepresented minority student involvement at Texas Tech, to high school teacher engagement at Illinois and undergraduate student participation at the U of San Diego, a mainly undergraduate institution.

PI：McKenna，Gregory B. / Schroeder，Charles / Anderson，Raeproposal编号：1603943 /1604038 /1603925该提案的目标是探索形成大环的聚合物分子的行为，而不是通常的线性聚合物分子。这样的聚合物，一个可以是DNA分子的示例，与加工时线性分子或在溶液中流动时的作用方式不同，因为链中没有末端。这项工作的结果可能会导致改进的聚合物材料，以详细了解生物分子的行为以及用于DNA测序的新技术。圆形聚合物是吸引人的材料，几十年来激发了聚合物理论家和实验者。由于没有链端，圆形链的动力学与线性对应物的根本不同。然而，尽管最近取得了进展，但圆形拓扑对聚合物动力学的影响仍然是该领域的关键尚未解决的问题。在此提案中，PI有望通过制备单分散和高拓扑纯度的圆形和线性DNA分子来取得我们的理解。组装团队具有合成和表征圆形和线性DNA的专业知识，并将研究这些材料在浓度范围更大的浓度和分子量范围内的流变行为。提出了一种全面的方法，该方法将包括宏观和微风格，单分子聚合物动力学和DNA合成，以提供有关线性和圆形DNA动力学的新信息。除了提供出发点以理解其圆形对应物外，线性纠缠DNA的平行研究还将使用完美的单分散DNA样品提供前所未有的数据，以直接测试来自转推理论的预测，例如，在极高的纠缠密度下的交叉至重置行为。除研究生的参与外，在所有三个合作机构中都提出了教育活动，从不足的少数族裔学生参与到德克萨斯理工学院，到伊利诺伊州的高中教师参与以及在圣地亚哥U的本科学生参与，这是一家主要是本科生的学院。