MRI: Acquisition of a Nuclear Magnetic Resonance Spectrometer for Marine Biogeochemical Research

MRI：购买核磁共振波谱仪用于海洋生物地球化学研究

• 批准号: 1828581
• 负责人: Daniel Repeta
• 金额: $ 62.01万
• 依托单位: Woods Hole Oceanographic Institution
• 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: 2018-10-01 至 2020-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1828581&HistoricalAwards=false
• 关键词: MRI; Acquisition; Nuclear; Magnetic; Resonance

Ocean productivity, the health of our planet, and many of the resources foundational to our modern society, are in large part by-products by how very tiny, single celled microbes manufacture and degrade organic compounds in the ocean. Each day ocean microbes synthesize enormous quantities of proteins, sugars, and fats. In doing so, they manufacture a large share of the oxygen we breathe, they remove harmful carbon dioxide from the atmosphere, and they serve as food for many commercially important species of marine fish and crustaceans. Microbes "clean" seawater of pollutants, and serve as the base of marine ecosystems. However, marine microbes live a very competitive environment. The nutrients that microbes need to grow and thrive are extremely scarce, and nutrient cycling is extraordinarily efficient. Even small disturbances in microbial nutrient cycles can have major consequences; oxygen in seawater can disappear, and ecosystems can collapse. To understand how microbial cycles operate, we need to identify and track organic compounds and nutrients that are key to sustaining microbial life. Here we request funds to refurbish and modernize a nuclear magnetic resonance (NMR) spectrometer for use in a broad suite of marine biogeochemical studies designed to understand microbial nutrient cycles. The instrument will allow a number of scientists, students and staff at the Woods Hole Oceanographic Institution (WHOI) to identify key organic nutrient compounds that microbes use to extract nutrients from seawater, fend off predation, and shield themselves from harmful UV radiation. The instrument will also be critical to training the next generation of marine scientists through the WHOI postdoctoral and summer student fellowship programs, and the WHOI/MIT Joint Graduate Program in ocean sciences.Iron and phosphorus are two nutrients that limit and shape marine microbial communities across large tracts of the ocean. The chemical forms of marine iron and phosphorus are largely unknown, and over the next few years, we propose use the NMR spectroscopy to identify iron, copper, cobalt, and phosphorus containing organic compounds. Initial results have allowed us to show that the degradation of organic phosphonates is a source of atmospheric methane and ethylene, and that siderophores, compounds synthesized by marine microbes to extract iron from the environment, are actively produced in regions of the ocean where iron is scarce. We will continue this work through the US GEOTRACES program, which will measure trace metal and nutrient abundances across the Pacific Ocean from Alaska to Tahiti. Many organic compounds and organic nutrients are supplied by dust and river discharge into ocean margins. Determining the chemical identity of terrestrial organic matter entering the ocean, and its availability to marine microbial communities is key to understanding microbial nutrient cycles. A second focus of our research over the next few years will be in using enhanced NMR techniques to better characterize the nature and transformations of terrestrial organic matter as it enters the ocean.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.

海洋的生产力，我们地球的健康，以及我们现代社会的许多基础资源，在很大程度上都是非常微小的单细胞微生物在海洋中制造和降解有机化合物的副产品。海洋微生物每天合成大量的蛋白质、糖和脂肪。在这样做的过程中，它们制造了我们呼吸的大部分氧气，它们从大气中清除有害的二氧化碳，它们是许多商业上重要的海洋鱼类和甲壳类动物的食物。微生物“清洁”海水中的污染物，并作为海洋生态系统的基础。然而，海洋微生物生活在竞争非常激烈的环境中。微生物生长和繁荣所需的营养物质极其稀缺，而营养循环非常有效。微生物营养循环中即使很小的扰动也会产生严重的后果；海水中的氧气会消失，生态系统会崩溃。为了了解微生物循环是如何运作的，我们需要识别和跟踪维持微生物生命的关键有机化合物和营养物质。在此，我们请求资金翻新和现代化核磁共振（NMR）光谱仪，用于广泛的海洋生物地球化学研究，旨在了解微生物营养循环。该仪器将使伍兹霍尔海洋研究所（WHOI）的一些科学家、学生和工作人员能够识别微生物用来从海水中提取营养物质、抵御捕食和保护自己免受有害紫外线辐射的关键有机营养化合物。该仪器对于通过WHOI博士后和暑期学生奖学金计划以及WHOI/MIT海洋科学联合研究生计划培训下一代海洋科学家也至关重要。铁和磷是两种限制和塑造大面积海洋微生物群落的营养物质。海洋铁和磷的化学形式在很大程度上是未知的，在接下来的几年里，我们建议使用核磁共振光谱来识别含铁、铜、钴和磷的有机化合物。初步结果表明，有机膦酸盐的降解是大气中甲烷和乙烯的一个来源，而铁载体，一种由海洋微生物合成的从环境中提取铁的化合物，在缺乏铁的海洋区域积极产生。我们将通过美国GEOTRACES项目继续这项工作，该项目将测量从阿拉斯加到塔希提岛横跨太平洋的痕量金属和养分丰度。许多有机化合物和有机营养物是由灰尘和河流排放到海洋边缘的。确定进入海洋的陆源有机物的化学特性及其对海洋微生物群落的可利用性是了解微生物营养循环的关键。未来几年我们研究的第二个重点将是使用增强的核磁共振技术来更好地表征陆地有机物进入海洋时的性质和转变。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。