Unraveling at Micro- and Macro-scale the Mineral Surface Reactions of Amino Acids and Small Peptides Using Phage Display Technology Coupled with Synchrotron-Based Spectroscopy

使用噬菌体展示技术与同步加速器光谱学相结合，在微观和宏观尺度上揭示氨基酸和小肽的矿物表面反应

• 批准号: 0949653
• 负责人: Michael Cox
• 金额: $ 20万
• 依托单位: Mississippi State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-01 至 2013-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0949653&HistoricalAwards=false
• 关键词: Unraveling; Micro; Macro; scale; Mineral

Intellectual merit: The latest terrestrial N cycle paradigm considers soluble organic nitrogen (SON) as a rate limiting step for regulating the overall N availability in ecosystems. Our lack of understanding of the micro-scale processes/mechanisms of interactions between soil minerals and SON compounds hinders our ability to predict N flux between different soil compartments at the ecosystem-scale. To address this issue, an interdisciplinary approach that combines a broad array of novel molecular, biological, and synchrotron-based spectroscopic techniques is proposed to investigate the interaction mechanisms between soil minerals and amino acids and small peptides, two key components of soil SON. Novel methods will be used to achieve the research. The phage display technique will be used to screen, in a short period of time, billions of random small peptide sequences for those peptides displaying a selective affinity for a particular mineral surface. Macro-scale adsorption isotherms for amino acids and small peptides on four minerals commonly found in soil will be obtained. Using the samples collected from the adsorption isotherms experiment, polarization-dependent N (1s) near-edge x-ray absorption fine structure (NEXAFS) will be used to investigate, at micro-scale, the average molecular surface orientation. Lastly, a microbial essay method will be used to understand at micro-scale how molecular surface organization on mineral surfaces affects the microbial utilization of adsorbed amino acids and small peptides.Broader impacts: The PIs are cooperating with two local high schools (The Mississippi School for Mathematics and Science and The West Oktibbeha County High School) to recruit future minority undergraduate students for summer research projects. Those summer research projects will provide minority high school students opportunities to gain hands?]on experience in biogeochemistry research and state of the art instrumentations, to obtain insight into the nature of both undergraduate and graduate school, to work with university professors and graduate students as an interdisciplinary team, and to have informed choices about how to advance their future career. The students will also be given the opportunity to attend regional or national meetings and to visit national laboratories. The work from these students and the research of this proposal will be showcased at their high schools and highlighted in state competitions such as the Engineering Fair and the Young Scientist Division at the Mississippi Academy of Science.

智力优点：最新的陆地氮循环范式认为可溶性有机氮（SON）作为一个限速步骤，调节生态系统中的整体N的可用性。我们缺乏对土壤矿物和SON化合物之间相互作用的微观过程/机制的了解，阻碍了我们在生态系统尺度上预测不同土壤隔间之间的N通量的能力。为了解决这个问题，提出了一个跨学科的方法，结合了广泛的新的分子，生物和同步辐射光谱技术，以调查土壤矿物质和氨基酸和小肽，土壤SON的两个关键组成部分之间的相互作用机制。新的方法将被用来实现研究。噬菌体展示技术将用于在短时间内筛选数十亿个随机小肽序列，以筛选对特定矿物表面显示选择性亲和力的那些肽。获得了氨基酸和小肽在土壤中常见的四种矿物上的宏观吸附等温线。使用从吸附等温线实验中收集的样品，偏振相关的N（1 s）近边X射线吸收精细结构（NEXAFS）将被用来调查，在微观尺度上，平均分子表面取向。最后，将使用微生物论文方法在微观尺度上了解矿物表面的分子表面组织如何影响微生物对吸附的氨基酸和小肽的利用。更广泛的影响：PI正在与当地两所高中（密西西比数学与科学学院和西奥克蒂贝哈县高中）合作，招募未来的少数族裔本科生参加夏季研究项目。那些暑期研究项目将为少数民族高中生提供获得手的机会？在地球化学研究和最先进的仪器状态的经验，以获得洞察本科和研究生院的性质，与大学教授和研究生作为一个跨学科的团队工作，并有关于如何推进他们未来的职业生涯知情的选择。学生还将有机会参加区域或国家会议，并参观国家实验室。这些学生的工作和这项提案的研究将在他们的高中展示，并在密西西比科学院的工程博览会和青年科学家分部等州际比赛中突出展示。