CAREER: Hierarchical Self-Assembly of Biopolymers

ID：MPS/DMR/BMAT(7623)0955776 PI：Dogic，Zvonimir ORG：Brandeis University标题：Career：生物聚合物的层次化自组装特性优点：基于生物聚合物的材料经常被组织成复杂的层次化结构，跨越从纳米到毫米的多个长度尺度。本研究的目标是阐明生物聚合物自组装成宏观材料的途径，并将这些宏观材料的结构、力学和光学性质与组成生物聚合物的基本介观相互作用和微观结构联系起来。该提案有两个具体目标。第一个目标是确定单个生物聚合物的连续介观性质如何在微观水平上受到组成蛋白质突变的影响。第二个目标是了解宏观胶体膜的结构和相互作用。在这里，有吸引力的耗尽相互作用被用来将数千个棒组装成由单层排列的棒组成的平衡膜状结构。这两个实验目标在几个重要方面相互关联：它们都需要使用相同的生物聚合物模型系统。它们还涉及类似的实验技术和技术。最后，他们探讨了分层组装的中心主题，每个目标都侧重于不同层次的分层，从单丝到包含数千根丝的组装。了解生物聚合物在任何一个层次上的组合代表着该领域的一项重大进步。然而，只有结合所有相关长度尺度的结构和动力学的理解，才能得出自下而上的一般设计原则。具有预定结构和机械性能的新型纳米结构材料的工程学。从技术的角度来看，特别强调直接可视化所有层级的生物聚合物组合。利用电子显微镜，PI将以纳米分辨率确定生物聚合物的3D构象。利用光学显微镜，他将同时显示组合中单个细丝的动态以及整个组合的结构和动态。更广泛的影响：通过相互强调可视化技术和跨学科的科学方法，研究和教育计划无缝地结合在一起。拟议的教育计划包含四个相关的目标。具体地说，(1)PI和合作者将继续开发一门以光学显微镜为重点的跨学科实验室课程。由于显微镜被用于许多学科，他们将确保所有科学背景的学生都能接触到这门课程。(2)他们将把各级教育的学生，从高中生到高级研究生，纳入正在进行的积极的研究计划。(3)他们将开发一个专注于显微图像定量分析的虚拟在线实验室。任何地方的学生都可以远程下载实际实验数据，并使用定制编写的软件执行所有后续图像分析和数据还原步骤。(4)最后，他们将在马萨诸塞州阿克顿的发现博物馆开发一个永久性展览，利用光学显微镜在微观尺度上一瞥一个高度动态的世界。这四个目标的成功实现将造就新一代的学生，他们在显微镜基础方面得到了更好的培训。它还将激励年轻人从事与科学有关的职业，并提高普通观众对科学研究和光学显微镜重要性的认识。

ID: MPS/DMR/BMAT(7623) 0955776 PI: Dogic, Zvonimir ORG: Brandeis UniversityTitle: CAREER: Hierarchial Self-Assembly of BiopolymersINTELLECTUAL MERIT: Biopolymer-based materials are frequently organized into complex hierarchical structures that span multiple length scales ranging from nanometers to millimeters. The goal of this research is to elucidate pathways by which biopolymers self-assemble into macroscopic materials and relate the structure, mechanical and optical properties of these macroscopic materials to the underlying mesoscopic interactions and microscopic architecture of the constituent biopolymers. The proposal has two specific aims. The first aim is to determine how the continuum mesoscopic properties of individual biopolymers are affected by the mutations of the constituent proteins at the microscopic level. The second aim is focused on understanding the structure and interactions of macroscopic colloidal membranes. Here, attractive depletion interactions are used to assemble thousands of rods into an equilibrium membrane-like structure composed of a monolayer of aligned rods. These two experimental aims are related to each other in several important ways: They both require use of the same biopolymer model systems. They also involve similar experimental techniques and technologies. Finally, they explore the central theme of hierarchical assembly, with each aim focusing on a different level of hierarchy ranging from single filaments to assemblages containing thousands of filaments. Understanding biopolymer assemblages at any one level of hierarchy represents a significant advance in the field. However, only the combined understanding of structure and dynamics at all relevant length scales will result in general design principles required for a ?bottom up? engineering of novel nanostructured materials with predefined structural and mechanical properties. From a techniques perspective special emphasis is being placed on directly visualizing biopolymer assemblages at all levels of hierarchy. Using electron microscopy the PI will determine 3D conformations of biopolymers with nanometer resolution. With optical microscopy he will simultaneously visualize dynamics of individual filaments within an assemblages as well as the structure and dynamics of entire assemblages. BROADER IMPACTS: The research and education plans are seamlessly joined together through their mutual emphasis on visualization techniques and interdisciplinary approach to science. The proposed educational plan contains four related aims. Specifically, (1) the PI and collaborators will continue development of an interdisciplinary laboratory course focused on optical microscopy. Since microscopy is used in numerous disciplines; they will ensure that the course is accessible to students from all scientific backgrounds. (2) They will integrate students at all levels of education, ranging from high school students to advanced graduate students, into the ongoing vigorous research program. (3) They will develop a virtual online laboratory focused on the quantitative analysis of microscopy images. Students anywhere will be able to remotely download actual experimental data and perform all the subsequent image analysis and data reduction steps using custom written software. (4) Finally, they will develop a permanent exhibit at The Discovery Museum in Acton, Massachusetts, which will use optical microscopy to provide a glimpse into a highly dynamic world at microscopic length scales. Successful implementation of these four aims will result in a new generation of students who are better trained in the fundamentals of microscopy. It will also motivate young minds to pursue science related careers and increases awareness of the importance of scientific research and optical microscopy amongst the general audience.