Collaborative Research: Microbial Biomarkers at the Chemocline of the Cariaco Basin: Linking Organic Geochemistry and Microbial Ecology

合作研究：卡里亚科盆地化学跃层的微生物生物标志物：有机地球化学和微生物生态学的联系

• 批准号: 0550654
• 负责人: Stuart Wakeham
• 金额: --
• 依托单位: Skidaway Institute of Oceanography
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-03-01 至 2011-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0550654&HistoricalAwards=false
• 关键词: Collaborative; Research; Microbial; Biomarkers; Chemocline; Collaborative; Research; Microbial; Biomarkers; Chemocline

In this project, researchers at the Skidaway Institute of Oceanography and the Pennsylvania State University will investigate the relationship between biomarker distributions and microbial processes at the chemocline of the Cariaco Basin, Venezuela. The overriding hypothesis is that chemoautotrophy within the chemocline produces a set of biomarkers with diagnostic isotopic compositions that, when deposited in underlying sediments, provides a record of water column chemoautotrophic carbon production and sedimentation in the Cariaco Basin. The fidelity of sedimentary biomarkers as indicators of water column microbial processes depends upon linking biomarkers with their microbial sources. The project has three specific objectives: 1) To obtain depth profiles of microbial biomarkers and microbial community structure through closely spaced sampling at the chemocline of the Cariaco Basin, and thereby evaluate lipid biomarker-source relationships. The investigators will also measure biomarkers in sediment trap samples and surface sediments to determine how well sediments record water column chemoautotrophy. 2) To apply state-of-the-art analytical techniques for biomarker analyses, notably high performance liquid chromatography/electrospray ionization ion trap multistage mass spectrometry (HPLC/ESI-IT-MSn) to analyze intact bacterial and archaeal biomarkers. The investigators contend that the biomarker potential of intact polar lipids (IPLs) is significantly greater than that obtained by traditional hydrolysis based analyses. 3) To fully exploit the biogeochemical information inherent in lipid biomarkers by linking biomarkers with their biological sources and the processes by which they are produced. Spatial and temporal patterns in molecular and microbial signatures will form the foundation for understanding these linkages, which will be strengthened by companion measurements of the 13C content of lipids and key carbon substrates (methane, inorganic carbon, and if available, acetate). This cross-disciplinary project has a number of broader impacts. Most of the biomarker work will be carried out by Skidaway Institute of Oceanography, but the project is a collaborative effort between investigators having expertise in diverse disciplines and representing several laboratories in the US, Europe, and Venezuela. At Skidaway, a postdoctoral investigator will focus on the organic geochemical component and will work closely with the various organic geochemical partners (NIOZ, Bremen). Venezuelan scientists will participate on cruises in order to provide additional interaction and training.

在该项目中，Skidaway海洋学研究所和宾夕法尼亚州立大学的研究人员将调查委内瑞拉Cariaco Basin化学领域的生物标志物分布与微生物过程之间的关系。压倒性的假设是，化学素中的化学自动营养物产生一组具有诊断同位素组成的生物标志物，当沉积在潜在的沉积物中时，它们提供了水柱化学自养生碳的产生记录，并在Cari​​aco Basin中提供了沉积物。沉积物生物标志物作为水柱微生物过程的指标的保真度取决于将生物标志物与微生物来源联系起来。该项目具有三个特定的目标：1）通过紧密间隔的采样在Cari​​aco盆地的化学素中获得微生物生物标志物和微生物群落结构的深度曲线，从而评估了脂质生物标志物 - 源关系。研究人员还将测量沉积物陷阱样品和表面沉积物中的生物标志物，以确定沉积物如何记录水柱化学疗法。 2）将最先进的分析技术应用于生物标志物分析，尤其是高性能液相色谱/电喷雾离子陷阱多稳定质谱法（HPLC/ESI-IT-MSN）来分析完整的细菌和古细菌生物标志物。研究人员认为，完整的极性脂质（IPL）的生物标志物潜力明显大于基于传统水解的分析获得的生物标志物。 3）通过将生物标志物与其生物学来源及其产生的过程联系起来，充分利用脂质生物标志物固有的生物地球化学信息。分子和微生物特征中的空间和时间模式将构成理解这些联系的基础，通过对脂质和关键碳底物的13C含量（甲烷，无机碳，以及乙酸）的13C含量（甲烷，无机碳）的伴随测量来加强。这个跨学科项目具有更广泛的影响。大多数生物标志物工作将由Skidaway海洋学研究所进行，但是该项目是在各种学科方面具有专业知识的调查人员与代表美国，欧洲和委内瑞拉的几个实验室之间的合作努力。在Skidaway，博士后研究员将专注于有机地球化学成分，并将与各种有机地球化学伙伴（Nioz，Bremen）紧密合作。委内瑞拉科学家将参加巡航，以提供其他互动和培训。