Collaborative Research: Tracking chemical, isotopic, and molecular signatures of tightly coupled sulfur cycling in phototrophic and chemosynthetic microbial ecosystems

合作研究：追踪光养和化学合成微生物生态系统中紧密耦合的硫循环的化学、同位素和分子特征

• 批准号: 1124014
• 负责人: Gregory Druschel
• 金额: $ 8.84万
• 依托单位: University of Vermont & State Agricultural College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-03-15 至 2012-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1124014&HistoricalAwards=false
• 关键词: Collaborative; Research; Tracking; chemical; isotopic

The metabolic activity of microorganisms dominates the biogeochemical evolution of the Earth over geologic time. One of the fundamental questions facing scientists seeking to understand global biogeochemistry is: What is the relationship between microbial community composition (who¡¦s there?), metabolic activity (what are they doing?), and ambient environmental conditions (e.g., pH, sulfate levels) (how are they impacted?). Sulfur cycling, particularly the coupling between sulfate reduction and sulfide oxidation, is one of the dominant geochemical pathways driving carbon mineralization within many diverse microbial ecosystems today. Isotopic and mineralogical evidence recovered from ancient rocks suggest biological sulfate reduction played an important role on early Earth as well. In attempt to better understand this globally important process and the corresponding biosignatures of active sulfur cycling microorganisms, we are proposing a multi-disciplinary, high-resolution geochemical and molecular biological investigation of closely coupled microbial sulfur cycling in three representative microbial ecosystems. These include a 3-4 member synergistic anoxygenic phototrophic consortium, moderately diverse chemosynthetic sulfur-oxidizing mats, and highly complex benthic oxygenic photosynthetic microbial mats. These systems differ in terms of biological complexity and in the major sulfur cycling pathways, that collectively will provide fundamental information regarding light-dependent and -independent sulfur metabolisms. Our work combines analyses at high spatial (?Ým-scale) resolution of sulfur and carbon isotopic data using secondary ion mass spectrometry (SIMS) and FISH-nanoSIMS, microvoltammetic sulfur species measurements, and CARD-FISH molecular imaging to investigate the linkage among microbial spatial organization, metabolic activity, and establishment of geochemical gradients by coupled sulfur cycling communities. Together, the data from this combined laboratory and field study will develop a new toolset that can be used to study tightly coupled sulfur cycling on an unprecedented scale within microbially dominated sedimentary environments. This project will inform scientists about the fundamental chemistry and biology governing sulfur in the environment, past and present. This is important because sulfur plays a critical role in processes controlling not only how we view the evolution of life on this planet, but also about ore deposits as sources of metal resources, oil and gas formation and their economic recovery, soil nutrient availability affecting crop yields and the quality of water resources, and the transport of many contaminants in ground and surface waters. Additionally this project will help train the next generation of scientists with the scientific and technical knowledge to work in high tech and scientific industry, research, and education fields.

微生物的代谢活性在地质时代占主导地球的生物地球化学演化。试图了解全球生物地球化学的科学家面临的基本问题之一是：微生物社区组成（谁在那里？），代谢活动（他们在做什么？）和环境环境条件（例如，pH，硫酸盐，硫酸盐水平）之间有什么关系（它们受到影响？）。硫酸盐循环，特别是硫酸盐还原和硫化物氧化之间的耦合，是当今许多不同微生物生态系统中驱动碳矿化的主要地球化学途径之一。从古代岩石中回收的同位素和矿物证据表明，硫酸盐的生物学还原也在地球早期也起着重要作用。为了更好地理解这一全球重要的过程以及主动硫循环微生物的相应生物签名，我们提出了三个具有三位代表的微生物生态系统的多核学科，高分辨率地球化学和分子生物学研究。其中包括一个3-4个成员协同缺氧的光营养联盟，中等多样的化学合成硫氧化垫和高度复杂的底栖省氧光合成微生物垫。这些系统在生物复杂性和主要的硫循环途径方面有所不同，这些途径将共同提供有关光依赖性和独立硫代谢的基本信息。我们的工作结合了使用次级离子质谱法（SIMS）和FISH-NONOSIMS的高空间（？m级）分辨率分析的分析，微量毒素硫的物种测量值和卡片 - 鱼类分子成像，以研究微生物的持续型群体，并建立了地理，并建立了地理，地理，向持续的群体建立了地理，地理，转移的群体，地理，转移，coch式的群体，循环型，传播，循环群体，传给了持续的持续。骑自行车社区。总之，这项联合实验室和现场研究的数据将开发出一种新的工具集，该工具集可用于在微生物支配的沉积环境中以空前的规模研究紧密耦合的硫循环。该项目将向科学家提供有关过去和现在环境中硫磺的基本化学和生物学。这很重要，因为硫磺不仅在控制这个星球上的生命进化方面起着至关重要的作用，而且还涉及矿床作为金属资源的来源，石油和天然气形成及其经济回收，影响农作物产量和水资源质量以及许多污染物在地面和地表水域中的运输。此外，该项目将帮助培训下一代科学家的科学和技术知识，以在高科技和科学行业，研究和教育领域工作。