Microbial Cycling of Dissolved Organic Phosphorus in the Oligotrophic North Atlantic: The Nucleic Acid Connection

寡营养北大西洋溶解有机磷的微生物循环：核酸联系

基本信息

批准号：
9019415
负责人：
James Ammerman
金额：
$ 16.76万
依托单位：
Texas A&M Research Foundation
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
1991
资助国家：
美国
起止时间：
1991-03-01 至 1993-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=9019415&HistoricalAwards=false
关键词：
Microbial Cycling Dissolved Organic Phosphorus

项目摘要

Despite a major focus on nitrogen as the limiting nutrient in marine ecosystems, there is evidence that in some marine environments, especially the vast oligotrophic central gyres, that phosphate appears to be refractory and potentially limiting, although a fraction of the phosphate pool does appear to turn over rapidly. Dissolved nucleic acids will be examined as a model component of this rapidly-cycling fraction, because many of the breakdown rates and the concentrations of the resulting intermediates can be measured. These parameters will be measured by a combination of fluorometric, isotopic, and spectrophotometric techniques and will be compared to parallel measurement of the major phosphate pools and fluxes. This project will test the hypotheses that microbial breakdown of dissolved nucleic acids is both: 1) a quantitatively important pathway, and 2) a model pathway for the cycling of labile dissolved organic phosphate in the oligotrophic North Atlantic. This research will further our understanding of the cycling of dissolved organic phosphate, a suite of compounds with potentially global importance to marine primary production. Furthermore, this research will lead to insights into microbial processes of biopolymer and monomer breakdown. Finally, since dissolved nucleic acids are genetic material and also significant reservoirs of dissolved organic carbon and nitrogen, these studies will increase our knowledge of environmental gene transfer and of dissolved organic carbon and nitrogen cycling in the environment.

尽管主要关注氮作为海洋生态系统中的限制营养素，但有证据表明，在某些海洋环境中，尤其是广阔的贫营养中心回旋中，磷酸盐似乎是磷酸盐似乎是磷酸盐池的一小部分，但磷酸盐似乎确实迅速转移了。溶解的核酸将作为此快速循环分数的模型组成部分，因为可以测量许多分解速率和所得中间体的浓度。这些参数将通过荧光，同位素和分光光度计技术的组合来测量，并将与主要磷酸盐池和通量的平行测量进行比较。该项目将检验以下假设：溶解核酸的微生物分解既是：1）一种定量重要的途径，以及2）一种模型途径，用于在北大西洋中循环不稳定溶解的有机磷酸盐。这项研究将进一步理解溶解有机磷酸盐的循环，这是一套对海洋初级生产具有全球重要性的化合物。此外，这项研究将导致对生物聚合物和单体分解的微生物过程的见解。最后，由于溶解的核酸是遗传物质，也是溶解有机碳和氮的重要储层，因此这些研究将增加我们对环境基因转移以及溶解有机碳和氮气环境中溶解的知识。