Amplification of chiral recognition and discrimination among amino-acid-based nanoscale ions during assembly induced by electrostatic interaction

静电相互作用诱导组装过程中氨基酸纳米级离子之间手性识别和辨别的放大

• 批准号: 2309886
• 负责人: Tianbo Liu
• 金额: $ 39.96万
• 依托单位: University of Akron
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-01-01 至 2026-12-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2309886&HistoricalAwards=false
• 关键词: Amplification; chiral; recognition; discrimination; among

This award supports experimental research and education aimed at understanding how chirality is maintained and amplified during the formation of superstructures by charged macromolecules. Most biomacromolecules like proteins and DNA are chiral, that is, the same molecule has two different geometrical forms which cannot be superimposed onto its mirror image. Although both forms are considered identical in chemical and physical properties except their handedness, exclusively L-amino acids in proteins and D-sugars are found in biological systems – a phenomenon called homochirality. Many interesting phenomena have been discovered, such as that charged chiral species only seek their own kind when forming large structures (chiral recognition), and under certain conditions only one form will assemble while the other one stays as molecules in solution (chiral discrimination, which leads to homochirality). These are important topics in many fields from life sciences to catalysis and separation science. The PI will explore the conditions needed for achieving such phenomena in solution by studying nanoscale intermolecular physical interactions, especially the long-range electrostatic interaction between different chral components, which is the probable driving force. The project engages graduate and undergraduate students through the NSF-REU center, and the newly established BS program in Polymers, both at the School of Polymer Science and Polymer Eng. at the University of Akron, and high school students from northeast Ohio. The PI’s team will specifically recruit from local schools that serve large numbers of students from groups traditionally under-represented in STEM fields, encouraging students to take science courses and pursue STEM related careers.PI Tianbo Liu from the University of Akron will explore the nanoscale intermolecular interactions in dilute macroionic solutions containing multiple chiral components, by using metal-organic cages containing different chiral amino acid linkers as models . Such interactions are responsible for achieving chiral recognition (e.g., forming enantiomeric, chiral supramolecular structures instead of racemic mixed ones) and chiral discrimination and selection (e.g., only one enantiomer of chiral macroions will assemble, in the presence of small amount of chiral counterions or co-ions). The PI plans to design experiments to explore the probable key role of the long-range electrostatic interaction, represented by the interactions of chiral counterions or co-ions with the central chiral macroions, behind such phenomena, by examining the following hypotheses: (1) long-range electrostatic intermolecular interaction is critical for achieving chiral recognition between chiral macroions, resulting in pure enantiomeric supramolecular structures in racemic solutions instead of forming mixed assemblies; (2) a minor chiral environment (e.g., low concentrations of minor chiral counterions) is sufficient to achieve chiral selection (i.e., promoting one type of enantiomer to self-assemble while suppressing the other type) in chiral macroionic solution; (3) chiral selection of the metal organic cage macroions might become much more significant when the counterions (amino acids, e.g., Alanine) and the ligands of the metal organic cages are of the same type (e.g., Alanine); (4) chiral co-ions (ions carrying the same charge as the macroions) themselves alone might also be able to achieve chiral recognition and chiral selection of chiral macroions; and (5) minor chiral components can lead to the formation of chiral gels with tunable chirality. The PI’s team expects to contribute to our fundamental understanding of nanoscale intermolecular interactions by identifying the critical force leading to the chiral recognition and chiral selection of biomacromolecules, which further lead to many critical phenomena such as the homochirality feature of lives. The project engages graduate and undergraduate students through the NSF-REU center, and the newly established BS program in Polymers, both at the School of Polymer Science and Polymer Eng. at the University of Akron, and high school students from northeast Ohio. The PI’s team will specifically recruit from local schools that serve large numbers of students from groups traditionally under-represented in STEM fields, encouraging students to take science courses and pursue STEM related careers.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该奖项支持实验研究和教育，旨在了解通过带电的大分子在上层建筑期间如何维持和扩展手性的。大多数蛋白质和DNA（例如蛋白质）都是手性的，也就是说，同一分子具有两种不同的几何形式，这些形式不能叠加到其镜像上。尽管两种形式在化学和物理特性中都被认为是相同的，但它们的触手可及，但在蛋白质和D-糖中仅在生物系统中发现了L-氨基酸，这是一种称为同Rightality的现象。已经发现了许多有趣的现象，例如，充电的手性物种仅在形成大型结构（手性识别）时就寻求自己的种类，而在某些条件下，只有一种形式会组装，而另一种形式则作为溶液中的分子（手性歧视，导致同型）。这些是从生命科学到催化和分离科学的许多领域的重要主题。 PI将通过研究纳米分子间的物理相互作用，尤其是不同CHRAL成分之间的远距离静电相互作用，这是可能的驱动力，尤其是可能的驱动力。该项目通过NSF-REU中心与毕业生和本科生一起与聚合物科学和聚合物Eng的新成立的聚合物BS计划一起。在阿克伦大学和来自俄亥俄州东北部的高中生。 The PI’s team will specifically recruit from local schools that serve large numbers of students from groups traditionally under-represented in STEM fields, encouraging students to take science courses and pursuue STEM related careers.PI Tianbo Liu from the University of Akron will explore the nanoscale intermolecular interactions in dilute macroionic solutions containing multiple chiral components, by using metal-organic cages containing different chiral amino酸连接器作为模型。这种相互作用是为了实现手性识别（例如，形成对映体的，手性超分子结构而不是外围混合的结构）和手性歧视和选择（例如，只有手性宏的对映异构体将在少量的手学柜台或co-co-co-iverions或co-co-co-的情况下组装）。 PI计划设计实验，以探索远程静电相互作用的可能关键作用，这是通过手性柜台或共同离子与中央性手性宏的相互作用表示的，在这种现象背后，通过检查以下假设：（1）（1）远程静电互动至关重要的固定式插入量的固定量至关重要。极性溶液中的超分子结构，而不是形成混合的组件； （2）次要的手性环境（例如，低浓度的小手性话剂）足以实现手性宏观发电液溶液中的手性选择（即，在抑制另一种类型的同时，促进一种类型的参与者自我组装）； （3）当柜台（例如氨基酸，例如丙氨酸）和金属有机笼的配体具有相同类型（例如丙氨酸）时，手性的金属有机笼宏选择可能会变得更加重要。 （4）手性共同离子（带有与宏观相同电荷的离子本身）也可能能够获得手性识别和手性手性宏观的选择； （5）轻微的手性成分会导致具有可调手性的手性凝胶形成。 PI的团队希望通过确定导致手性识别和手性的生物乳球分子选择的关键力来为我们对纳米分子间相互作用的基本理解做出贡献，这进一步导致了许多关键现象，例如生命的同型同型特征。该项目通过NSF-REU中心与毕业生和本科生一起与聚合物科学和聚合物Eng的新成立的聚合物BS计划一起。在阿克伦大学和来自俄亥俄州东北部的高中生。 PI的团队将专门从当地学校招募，这些学校在STEM领域中为大量学生提供服务，鼓励学生参加科学课程和购买与STEM相关的职业。该奖项反映了NSF的法定任务，并通过使用该基金会的知识分子的智力和更广泛的影响来评估CRITERIA CRITERIA CRITERIA。