Collaborative Research: Resistance of Peptide Degradaton Products in Seawater

海洋系统中有机物的主要来源是光合微生物的原位初级生产。大部分产生的有机物在水柱和沉积物中再矿化，但一小部分通过成岩作用保存下来。对全球碳和氮收支特别重要的是有机物对腐烂和转化为难降解物质的固有抵抗力，这两者都使其从活性生物和非生物海洋循环中移除。然而，人们对这种难降解的大分子有机物的化学成分知之甚少，也不知道成岩过程中其抵抗作用的机制。来自纽约州立大学、石溪分校和老道明大学的科学家们提议确定在海洋环境中观察到的蛋白质、肽和氨基酸池分布的生物和化学基础。具体来说，他们计划比较多肽相互竞争的化学、物理和生物反应的速率，以更好地了解海水中蛋白质物质的分布、循环和命运。通过使用最先进的分析方法（即基质辅助激光解吸/电离质谱- maldi - ms，电喷雾质谱联用傅立叶变换离子回旋质谱- esi FTICR，二维核磁共振方法），主要研究人员计划合成具有生物学意义的肽，并监测其生产和去除速度。这将导致观察到化学和生物损失机制在各种环境中与光、pH值、营养和温度变化有关的重要性。就更广泛的影响而言，这项研究的结果将更好地了解有机物对微生物的生物利用度，有机物在水柱中变得更不可用的机制，以及有机物是如何保存的。来自纽约州立大学石溪分校的一名研究生和一名本科生，以及来自老道明大学的一名博士后和一名研究生将作为该项目的一部分得到支持和培训。该项目的成果和方法将纳入两所大学的研究生和本科生教育和培训。

The principal source of organic matter in marine systems is from in situ primary production by photosynthetic microorganisms. The bulk of the produced organic matter is remineralized in the water column and sediments, but a small fraction survives diagenesis to be preserved. Of particular importance to global carbon and nitrogen budgets is organic matter's inherent resistance to decay and its transformation into refractory substances, both of which remove it from the reactive biotic and abiotic marine cycles. Little is known, however, about the chemical composition of this refractory, macromolecular organic matter, or mechanisms contributing to its resistance during diagenesis.Scientists from the State University of New York, Stony Brook and Old Dominion University propose to determine the biological and chemical basis for the observed distribution of protein, peptide, and amino acid pools in the marine environment. Specifically, they plan to compare the rates of competing chemical, physical, and biological reactions of peptides to gain a better understanding of the distribution, cycling, and fate of proteinaceous material in seawater. Through the use of state-of-the-art analytical methods (i.e., matrix-assisted laser desorption/ionization mass spectrometry-MALDI-MS, electrospray mass spectrometry coupled to Fourier transform ion cyclotron mass spectrometry-ESI FTICR, 2D nuclear magnetic resonance approaches) the principle investigators plan to synthesize peptides of biological interest and monitor their rates of production and removal. This would lead to observations of the importance of chemical and biological loss mechanisms in various environments with respect to change in light, pH, nutrients, and temperature. As regards broader impacts, results from this study would provide a better understanding of the bioavailability of organic matter to microbes, the mechanisms where organic matter is rendered less available in the water column, and how organic matter is preserved. One graduate student and one undergraduate student from the State University of New York, Stony Brook, and one postdoc and one graduate student from Old Dominion University would be supported and trained as part of this project. Results and methods from this project would be integrated into graduate and undergraduate education and training at both universities.