Collaborative Research: Relating detrital peptide sequences to particulate organic matter diagenetic histories

合作研究：将碎屑肽序列与颗粒有机质成岩历史联系起来

• 批准号: 1457870
• 负责人: Lawrence Mayer
• 金额: $ 5.99万
• 依托单位: University of Maine
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-02-15 至 2018-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1457870&HistoricalAwards=false
• 关键词: Collaborative; Research; Relating; detrital; peptide

Biological, chemical, and physical processes alter recently deposited marine sediments. During this alteration, commonly referred to as early diagenesis, the quantity and composition of organic matter is changed which influences key components of the marine carbon cycle. In this study, researchers will use analytical techniques to evaluate the geochemistry of peptides during early diagenesis, and develop methods for assessing the role bacteria play. This research is important because organic molecules such as peptides influence degradation rates and the fate of carbon and nitrogen in the ocean, and therefore have broad relevance for understanding the geochemical cycling of these key nutrients. The project will also involve research opportunities for undergraduate and graduate students, as well as encourage diversity in the next generation of ocean scientists by providing summer internship opportunities for female middle school students from underrepresented communities (Project COOL).Most diagenetic indices for evaluating how "far along" organic matter is in its early diagenesis are based on amino acid compositions. Total hydrolyzable amino acid compositions indicate, in a coarse manner, organic matter degradation status, bioavailability, and source. Further development of amino acids as tools to assess geochemical processes requires including the wealth of information held within the peptide chains, information that is currently lost during hydrolysis. A powerful approach to sequencing detrital peptides is the application of tandem mass spectroscopy followed by de novo sequencing. In this project, researchers will use de novo sequencing to evaluate peptide and protein geochemistry during early diagenesis, and to develop a peptidoglycan-specific quantification method that allows utilization of the unique peptidoglycan peptide structures found in different bacteria. Specific actions to be taken under this project include (1) applying de novo sequencing to a set of well-characterized archive samples, (2) conducting a set of sorption experiments to evaluate the propensity for different detrital peptides to adhere to mineral surfaces and be protected from degradation, and (3) developing a quantitative method for measuring peptidoglycan peptides. By comparing detrital peptides to other known quantities of the sample set, relationships between organic matter diagenesis and peptide source, sequence, and preservation will be assessed.

生物，化学和物理过程改变了最近沉积的海洋沉积物。在这种改变期间，通常称为早期成岩作用，有机物的数量和组成发生了变化，从而影响了海洋碳循环的关键组成部分。在这项研究中，研究人员将使用分析技术来评估早期成岩作用期间肽的地球化学，并开发用于评估细菌发挥作用的方法。这项研究很重要，因为有机分子（例如肽）会影响海洋中碳和氮的降解率和命运，因此在理解这些关键营养物质的地球化学循环方面具有广泛的相关性。该项目还将涉及本科生和研究生的研究机会，并通过为来自代表性不足的社区的女性中学生提供暑期实习机会（Project Cool）（最酷的项目）来鼓励下一代海洋科学家的多样性。评估有机物的早期成核酸含量是基于氨基酸酸性组成的，以评估“沿着”有机物的“远处”有机物。总可水解氨基酸组成以粗糙的方式表明有机物降解状态，生物利用度和来源。氨基酸作为评估地球化学过程的工具的进一步开发需要，包括肽链中持有的大量信息，这些信息目前在水解过程中丢失的信息。对碎屑肽进行测序的强大方法是串联质谱的应用，然后是从头测序。在该项目中，研究人员将使用从头测序来评估早期成岩作用期间肽和蛋白质地球化学，并开发一种肽聚糖特异性定量方法，该方法允许利用不同细菌中的独特肽聚糖肽结构。该项目下要采取的具体操作包括（1）将从头测序应用于一组良好的档案样本，（2）进行一组吸附实验，以评估不同碎屑肽的倾向，以粘附于矿物质表面上，并保护降解剂，以及（3）用于测量peptscun的定量方法。通过将碎屑肽与其他已知量的样品集进行比较，将评估有机物物质成岩和肽来源，序列和保存之间的关系。