Nano-Reactor Assembly Across Multiple Lengthscales

非技术性：这项由印第安纳州大学材料研究部生物材料项目授予的奖项是利用生物过程和定向自组装来制造新一代材料，以克服其局限性。研究人员将生物细胞视为设计新的复杂材料的灵感，这些材料由许多不同长度尺度的分子组分组装而成。目前，即使是最简单的生命系统也表现出远远超出合成模仿能力的复杂性。生物细胞对环境压力的反应能力在于它们调节酶介导反应的生化网络的能力。利用酶和酶网络的能力和复杂性来合成开发复杂的催化材料还没有实现，部分原因是酶的脆弱性及其与材料加工方法的不相容性。该项目将开发一套设计规则，将材料特性和催化功能纳入生物启发材料。该研究人员预计这些材料将在生物设计催化领域产生影响，并且它们的利用将导致开发更节能，可再生，安全和负担得起的技术。作为该项目的一个组成部分，该研究员将继续开发科学推广计划，其中参与尖端科学的本科生和研究生也将学习有效地将他们的研究传达给公众，并激励下一代科学家。这将通过与当地和地区学校的合作伙伴关系来实现，教师，学生和研究人员之间的长期关系可以培养对科学的热情，并与科学代表性不足的青年和社区建立联系。技术：使用生物启发的方法，这个研究者会发展出一个复杂的自我组装系统，以创建蛋白质笼结构，其中多个拷贝的多达3种酶以受控的邻接和化学计量封装。这些酶进行耦合级联反应，产生能够影响甲醇（和潜在的甲烷）氧化的合成代谢途径的材料。此外，一个数学模型的开发用于预测耦合反应的动力学在共本地化条件下，基于伙伴酶之间的中间体的扩散长度。计划的动力学研究表明，连续酶之间的中间通道依赖于酶间距离以及两种酶的动力学参数之间的平衡，这一发现挑战了任何共定位将自动产生增强的整体活性的简单化观点。此外，单个纳米反应器颗粒可以组装成有序的分层阵列，为从单个蛋白质笼构建并具有设计的复杂催化性能的散装材料的程序化组装提供了前进的道路。因此，使用天然存在和设计的分子组分，研究人员将通过在多个长度尺度上定向自组装模块化构建块来构建复杂的催化活性材料。在这项研究的背景下，研究生培训将包括：使用冷冻电子显微镜和图像重建的结构研究，以评估自组装蛋白质笼结构内的酶包装;质谱法，以评估由于拥挤效应引起的酶动力学变化;动态和静态（多角度）光散射，以评估从分子组件到材料的自组装过程;小角度X射线散射（阿贡国家实验室（APS）和布鲁克海文国家实验室（NSLS II））来探测蛋白质笼材料组装中的长程有序。学生将接受相关表征技术的培训。

Non-technical: This award by the Biomaterials program in the Division of Materials Research to University of Indiana is to use biological processes and directed self-assembly to make a new generation of materials to overcome their limitations. The investigator sees the biological cell as an inspiration for the design of new complex materials, assembled from molecular components across many different length scales. Currently, even the simplest living systems exhibit complexity that is well beyond the ability to mimic synthetically. The power of biological cells to respond to environmental stress lies in their ability to regulate biochemical networks of enzyme-mediated reactions. Harnessing the power and complexity of enzymes, and enzyme networks, for the synthetic development of complex catalytic materials has not been realized in part due to the fragility of enzymes and their incompatibility with materials processing approaches. This project will develop a set of design rules to incorporate materials properties and catalytic functions to bioinspired materials. This researcher expects these materials to make impacts in areas of bio-designed catalysis and that their utilization will lead to the development of more energy-efficient, renewable, safe and affordable technologies. As an integral part of the project, this investigator will continue to develop science outreach programming wherein undergraduate and graduate students, participating in cutting-edge science, will also learn to effectively communicate their research to the general public and inspire the next generation of scientists. This will be achieved through partnerships with local and regional schools in which long-term relationships between teachers, students, and researchers can foster an excitement about science and connect with youth and communities that are underrepresented in the sciences.Technical: Using a bioinspired approach, this researcher will develop a complex self-assembling system to create protein cage architectures in which multiple copies of up to 3 enzymes are encapsulated with controlled adjacency and stoichiometry. These enzymes perform a coupled cascade of reactions, creating a material capable of effecting a synthetic metabolic pathway for methanol (and potentially methane) oxidation. In addition, a mathematical model is developed for predicting the kinetics for coupled reactions under co-localized conditions, based on the diffusion length of intermediates between partner enzymes. The planned kinetic studies showed that intermediate channeling between sequential enzymes is dependent on both the inter-enzyme distance as well as a balance between the kinetic parameters of the two enzymes, a finding that challenges the simplistic view that any co-localization will automatically yield enhanced overall activities. In addition, individual nanoreactor particles can be assembled into ordered hierarchical arrays providing a path forward for the programmed assembly of bulk materials built from individual protein cages and having designed complex catalytic properties. Thus, using naturally occurring and designed molecular components, the investigator will construct complex catalytically active materials through directed self-assembly of modular building blocks at multiple lengthscales. Graduate student training in the context of this research will include: structural studies using cryo-electron microscopy and image reconstruction to evaluate the packing of enzymes within the self-assembled protein cage architectures; mass spectrometry to evaluate changes in enzyme dynamics due crowding effects; dynamic and static (multi-angle) light scattering to evaluate the self-assembly processes from molecular components to materials; small angle x-ray scattering (Argonne National lab (APS) and Brookhaven National Lab (NSLS II) to probe the long range order in the assembly of protein cage materials. The students will be trained in the relevant characterization techniques.