Quantitative Role of Glycine Betaine and DMSP in the Cellular Nitrogen and Sulfur Budgets of Marine Phytoplankton

甘氨酸甜菜碱和 DMSP 在海洋浮游植物细胞氮和硫收支中的定量作用

• 批准号: 9225051
• 负责人: Ronald Kiene
• 金额: $ 13.39万
• 依托单位: University of South Alabama
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-01-01 至 1997-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9225051&HistoricalAwards=false
• 关键词: Quantitative; Role; Glycine; Betaine; DMSP

Marine phytoplankton produce a variety of organic osmolytes including the nitrogenous compound glycine betaine (GBT) and its sulfur analog, dimethylsulfoniopropionate (DMSP). We believe that GBT and DMSP make large and hitherto unrecognized contributions to the cellular nitrogen and sulfur pools in many species of marine phytoplankton and to particulate organic nitrogen (PON) and particulate organic sulfur (POS) pools in surface seawater. Very little is known about the production, distribution and cycling of these labile biogenic compounds. Information from the literature and from our own preliminary studies suggests that many species of phytoplankton produce both GBT and DMSP simultaneously and that nitrogen availability may affect the relative proportions of GBT and DMSP. We therefore will conduct laboratory and field studies to test the following hypotheses: 1) GBT makes up a significant (5-20%) fraction of cellular nitrogen in certain species of marine phytoplankton. Likewise, DMSP is a major constituent of cellular sulfur; 2) As with DMSP, there is a relationship between taxonomy and GBT production; 3) The levels of GBT and GMSP in phytoplankton are a function of nitrogen availability, with use of DMSP favored under N-limitation: 4) phytoplankton take up GBT and DMSP from their surroundings and release them under certain conditions; 5) In the field production of GBT over DMSP, or selection of species which produce GBT, will be favored in high nitrogen environments. Our study will provide new and important data on the quantitative role of methylated nitrogen and sulfur osmolytes to the cellular nitrogen and sulfur budgets of phytoplankton and to PON and POS in the sea. This information will lead to a better understanding of the biological cycling of nitrogen and sulfur in the ocean. ***

海洋浮游植物产生多种有机渗透压物质，包括含氮化合物甘氨酸甜菜碱(GBT)及其硫磺类似物二甲基磺酸丙酸酯(DMSP)。我们认为，GBT和DMSP对许多海洋浮游植物的细胞氮和硫库以及表层海水中的颗粒有机氮(PON)和颗粒有机硫(POS)库有很大的贡献，但到目前为止还没有被认识到。人们对这些不稳定的生物源化合物的生产、分布和循环知之甚少。来自文献和我们自己的初步研究的信息表明，许多种类的浮游植物同时产生GBT和DMSP，氮的有效性可能会影响GBT和DMSP的相对比例。因此，我们将进行实验室和野外研究，以检验以下假设：1)GBT在某些海洋浮游植物中占细胞氮的很大比例(5%-20%)。同样，DMSP是细胞硫的主要成分；2)与DMSP一样，分类与GBT产生之间存在关系；3)浮游植物中GBT和GMSP水平是氮素有效性的函数，在N限制条件下使用DMSP：4)浮游植物从环境中摄取GBT和DMSP，并在一定条件下释放它们；5)在大田生产中，通过DMSP进行GBT生产，或选择产生GBT的品种，将有利于在高氮环境下进行GBT的生产。我们的研究将为甲基化氮和硫渗透调节浮游植物的细胞氮和硫收支以及对海洋PON和POS的定量作用提供新的重要数据。这些信息将有助于更好地了解海洋中氮和硫的生物循环。***