Chaotic synchronization of surface chemistry and vesicular assembly in hydrothermal microenvironments

水热微环境中表面化学和囊泡组装的混沌同步

• 批准号: 1807441
• 负责人: Victor Ugaz
• 金额: $ 45万
• 依托单位: Texas A&M Engineering Experiment Station
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1807441&HistoricalAwards=false
• 关键词: Chaotic; synchronization; surface; chemistry; vesicular

Victor Ugaz and Yassin Hassan of Texas A&M University are supported by the Chemistry of Life Processes Program in the Division of Chemistry to understand the interplay between thermal convection, chaotic mixing, and surface chemical reaction kinetics in microscale, pore-mimicking surroundings. The Cellular and Biochemical Engineering Program in the Division of Chemical, Bioengineering, Environmental, and Transport Systems (CBET) also contributes to this award. An unanswered question is how long-chain molecules were first synthesized from elementary building blocks. Pore networks permeating mineral formations near underwater hydrothermal vents such as those discovered recently in the Lost City and Mid-Atlantic Ridge have emerged as potential hot spots for such biochemical processes, both on Earth and elsewhere. However, the detailed synthesis mechanism remains unclear, because concentrations of the precursor compounds in the surrounding ocean waters would have been too dilute to initiate polymerization. Ugaz and Hassan's research is exploring a new transport process-chaotic thermal convection-that naturally arises in hydrothermal microenvironments. This process continually shuttles molecular precursors from the bulk fluid to targeted locations on catalytically-active solid boundaries. The investigators are quantitatively mapping the enrichment of biomolecular species that can be achieved via this process, utilizing a new experimental platform to probe its influence on surface reaction kinetics within microscale pore surroundings. The research is also exploring the use of this transport mechanism to orchestrate the assembly of macromolecular species into protocell-like vesicular bodies, to package long-chain molecules and maintain localized pH gradients. The design and construction of such protocells can provide valuable insight into cellular function, and has practical application to the design of biosynthetic reaction systems for biomanufacturing. The project is enhancing student education and training through innovative hands-on modules to design, build, and operate microscale convective reactors representative of prebiotic hydrothermal scenarios and key physicochemical processes central to the origin of life. Companion computational modules integrate practical simulations of convective flow (using lava lamps as a relatable example) with biochemical reaction kinetics, through combined lectures and computer labs.Professors Ugaz and Hassan are performing coordinated experiments and simulations to understand how microscale chaotic thermal convection synergistically promotes mixing of chemical species in the bulk, while simultaneously accelerating enrichment and vesicular protocell assembly and packaging at discrete locations in a microfluidic reactor. A coupled 3D computational flow and reaction model is being developed to quantify how bulk flow characteristics govern surface reaction and vesicular assembly kinetics. This framework is being applied to identify the role of chaos in mediating targeted enrichment, and in defining the range of thermal and geometric conditions conducive to accelerated surface reactions and protocell formation. These results are laying the foundation to elucidate the ability of chaotic thermal convection to mediate assembly of macromolecular species and their encapsulation in protocells, under conditions representative of subsea hydrothermal networks. The knowledge and insights gained from these studies are providing a deeper understanding of possible pathways through which the necessary precursors to metabolic and replicating systems can spontaneously emerge, both on Earth and elsewhere. Important processes beyond biochemistry are also catalyzed in hydrothermal microenvironments, suggesting a compelling role for thermal convective phenomena in governing the transport and reaction of carbon dioxide. The conceptual simplicity and relatability of microscale convective flows is providing the foundation for innovative hands-on educational experiences that guide students through the process of designing, building, and operating microscale convective reactors representative of hydrothermal activity.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.

德克萨斯农工大学的维克托乌加兹和亚辛哈桑得到了化学系生命过程化学项目的支持，以了解热对流，混沌混合和表面化学反应动力学之间的相互作用，在微尺度，孔隙模拟环境。化学，生物工程，环境和运输系统（CBET）部门的细胞和生物化学工程项目也有助于获得该奖项。 一个尚未回答的问题是，长链分子最初是如何从基本构件合成的。渗透在水下热液喷口附近的矿物层中的孔隙网络，例如最近在迷城和大西洋中脊发现的孔隙网络，已成为地球和其他地方发生这种生物化学过程的潜在热点。然而，详细的合成机理仍不清楚，因为周围海洋沃茨中的前体化合物浓度太低，无法引发聚合。Ugaz和哈桑的研究正在探索一种新的运输过程-混沌热对流-在热液微环境中自然产生。该过程不断地将分子前体从主体流体穿梭到催化活性固体边界上的目标位置。研究人员正在定量绘制通过这一过程可以实现的生物分子物种的富集，利用一个新的实验平台来探测其对微尺度孔隙环境中表面反应动力学的影响。 该研究还在探索使用这种运输机制来协调大分子物质组装成原始细胞样囊泡体，包装长链分子并保持局部pH梯度。 这种原细胞的设计和构建可以提供对细胞功能的有价值的洞察，并且对生物制造的生物合成反应系统的设计具有实际应用。 该项目正在通过创新的实践模块来加强学生的教育和培训，以设计，建造和操作微型对流反应器，代表生命起源前的热液情景和关键的物理化学过程。 配套的计算模块集成了对流的实际模拟（使用熔岩灯作为一个相关的例子）与生化反应动力学，通过联合讲座和计算机实验室。教授乌加兹和哈桑正在进行协调的实验和模拟，以了解如何微尺度混沌热对流协同促进混合的化学物种在散装，同时在微流控反应器中的离散位置加速富集和囊泡原始细胞组装和包装。一个耦合的3D计算流和反应模型正在开发中，以量化体流特性如何管理表面反应和囊泡组装动力学。这个框架被应用于确定的作用，在介导有针对性的富集，并在定义的范围内的热和几何条件有利于加速表面反应和原始细胞的形成混乱。 这些结果奠定了基础，阐明混乱的热对流介导组装的大分子物种和它们的封装在原始细胞的能力，在海底热液网络的条件下的代表。从这些研究中获得的知识和见解使人们更深入地了解可能的途径，通过这些途径，代谢和复制系统的必要前体可以在地球和其他地方自发出现。生物化学以外的重要过程也在热液微环境中被催化，这表明热对流现象在控制二氧化碳的运输和反应中起着令人信服的作用。微尺度对流流动的概念简单性和相关性为指导学生设计、建造和操作代表热液活动的微尺度对流反应堆的过程的创新实践教育经验提供了基础。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。