International Research Fellowship Program: Helical Chirality Amplification through Constitutional Dynamic Chemistry

国际研究奖学金计划：通过宪法动态化学放大螺旋手性

• 批准号: 0601296
• 负责人: Frantz Folmer-Andersen
• 金额: $ 13.75万
• 依托单位: Folmer-Andersen Frantz
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-01 至 2008-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0601296&HistoricalAwards=false
• 关键词: International; Research; Fellowship; Program; Helical

0601296Folmer-AndersenThe International Research Fellowship Program enables U.S. scientists and engineers to conduct nine to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad.This award will support a twenty-four-month research fellowship by Dr. Frantz Folmer-Andersen to work with Dr. Jean-Marie P. Lehn at Universite Louis Pasteur in Strasbourg, France.Biological systems have evolved with increasing order and complexity, which exist throughout multiple organizational levels, from the molecular to the macroscopic. At the root of this hierarchy lies information encoded by sequences of small (sub-nanometer) repeat units within biopolymers. This sequential information is processed several times over through non-covalent physical interactions, which may be thought of as interactional algorithms, to afford precisely folded biological machinery. The application of this strategy to the "bottom-up" synthesis of well-defined nano- and microscopic architectures necessitates control over the expression of structural information across size scales and hierarchical levels. The proposed activities seek to establish such control within purely synthetic systems through the design of programmed monomers, which contain structural features that direct higher-order oligomer folding in a predictable way. The interrelationship between molecular and oligomer structure will then be interrogated by way of constitutional dynamic chemistry (CDC), which relies on the reversible interchange of components as a means of generating diversity within oligomeric assemblies. Specifically, this work aims to use asymmetric monomers to generate chiral bias (preferred twist-sense) in reversibly linked helical oligomers; and then through CDC, to affect the preferential incorporation of one enantiomer of a racemic mixture of exogenous monomers into the biased oligomers. The experimental approach to enantioselection relies on diastereomeric interactions between the monomers and the helical superstructure. In light of the homochirality and helical structures of proteins and genetic material, the general process of chirality amplification demonstrated by this work reflects a plausible evolutionary mechanism. Further, this method of component selection may be applied to the general design of dynamic nanosystems. Such materials would be capable of selecting components from an available pool to build up prescribed nanoscale objects, and in response to stimuli, be induced to deconstruct the objects and build different ones by recombination of the component pool. The achievement of this type of spontaneous but controlled assembly and disassembly of molecular machines could strongly impact the fields of nanotechnology and materials science.

0601296Folmer-Andersen国际研究奖学金计划使美国科学家和工程师能够在国外进行9至24个月的研究。该计划的奖项提供了联合研究的机会，并利用国外独特或互补的设施、专业知识和实验条件。该奖项将支持Frantz Folmer-Andersen博士与Jean-Marie P.Lehn博士在法国斯特拉斯堡的Louis Pasteur大学合作的为期24个月的研究奖学金。生物系统随着越来越多的秩序和复杂性而发展，存在于从分子到宏观的多个组织级别。在这个层次结构的根部是由生物聚合物中的小(亚纳米)重复单元序列编码的信息。这种顺序信息通过非共价物理相互作用被多次处理，这可以被认为是交互算法，以提供精确折叠的生物机器。将这一策略应用于定义明确的纳米和微观结构的“自下而上”合成，需要控制跨尺寸尺度和层级的结构信息的表达。拟议的活动寻求通过程序化单体的设计在纯合成系统中建立这种控制，程序化单体包含以可预测的方式指导更高阶低聚物折叠的结构特征。分子和低聚物结构之间的相互关系将通过构成动态化学(CDC)的方式进行询问，该方法依赖于成分的可逆交换作为在低聚物组装中产生多样性的一种手段。具体地说，这项工作的目的是利用不对称单体在可逆连接的螺旋低聚物中产生手性偏置(首选扭转感觉)，然后通过CDC，影响外消旋单体混合物的一个对映体优先掺入有偏置的低聚物中。对映体选择的实验方法依赖于单体和螺旋超结构之间的非对映异构体相互作用。鉴于蛋白质和遗传物质的同质和螺旋结构，这项工作证明了手性扩增的一般过程反映了一种看似合理的进化机制。此外，这种元件选择方法可以应用于动态纳米系统的一般设计。这种材料将能够从可用的池中选择组件来建立指定的纳米级对象，并响应于刺激，被诱导解构对象并通过组件池的重组来构建不同的对象。这种自发但可控的分子机器组装和拆卸的实现，可能会对纳米技术和材料科学领域产生强烈的影响。