Survival of Proteins in Marine Systems: Role of Macromolecular Organic Matter

9711596 Hatcher将结合应用地球化学和生物化学工具，研究大分子有机物在海洋系统中长期稳定或隔离蛋白质氮方面的作用。这项研究将集中于已经从天然矿物质枯竭的海洋沉积物（百慕大的红树林湖）、秘鲁上升流带和圣巴巴拉盆地的海洋富含有机物的沉积物、海洋沉积物捕集器材料中获得的样本，以及从实验室降解的藻类中获得的样本，这些藻类生长在13摄氏度和15摄氏度的环境中。电泳技术和核磁共振将遵循蛋白质在实验室孵育期间纳入大分子池的命运。蛋白质在形成大分子有机物质中所起的作用将在沉积物中长期抵抗降解。为了解决这个问题，一种新的双/选择性标记实验将用于检查在降解过程中两个平行但选择性标记的藻类池中的碳和氮的交叉偶联。了解沉积物和沉积物圈闭物质中难降解含氮有机物质形成的机制和过程将提高我们对海洋系统氮循环的理解，也将为改进全球氮循环的预测模型提供一个概念框架。

9711596 Hatcher The role of macromolecular organic matter will be examined with respect to the long-term stabilization or sequestration of protein nitrogen in marine systems using the combined application of geochemical and biochemical tools. The study will focus upon samples already obtained from a natural mineral-matter depleted marine sediment (Mangrove Lake, Bermuda), oceanic organic-rich sediments from the Peru upwelling zone and the Santa Barbara Basin, oceanic sediment trap material, and on samples obtained from laboratory degradations of algae grown to enrich them in 13C and 15N. Electrophoretic techniques and NMR will follow the fate of protein in laboratory incubations during its incorporation into the macromolecular pool. Protein's role in forming macromolecular organic matter which resists degradation in sediments over the long term will be studied. To address this issue, a novel dual/selective labeling experiment will be used to examine any cross-coupling of carbon and nitrogen from each of two parallel but selectively labeled pools of algae during degradation. Understanding the mechanisms and processes involved in the formation of refractory nitrogen-containing organic material in sediments and sediment-trap material will improve our understanding of nitrogen cycling in marine systems and will also provide a conceptual framework for improved predictive models of global nitrogen cycling.