Laboratory and Field Studies on the Cycling of Archae- bacterial Lipids in the Orca Basin, an Anoxic Hypersaline Basin in the Gulf of Mexico

墨西哥湾缺氧高盐盆地 Orca 盆地古细菌脂质循环的实验室和现场研究

• 批准号: 8723072
• 负责人: Edward Van Vleet
• 金额: $ 17.37万
• 依托单位: University of South Florida
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-07-15 至 1991-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8723072&HistoricalAwards=false
• 关键词: Laboratory; Field; Studies; Cycling; Archae

In marine systems where high salinity, high temperature, low pH, or extreme anoxicity characterize the environment, archaebacteria (including methanogens, extreme halophiles, and thermoacidophiles) play a dominant role in the cycling of organic carbon. Isopranyl glycerol ethers have recently been recognized as a characteristic morphological feature in identifying and differentiating archaebacteria. In order to use these compounds as geomolecular markers, it is first necessary to understand their cycling in the environment. Dr. Van Vleet proposes to investigate potential diagenetic alteration products of these compounds using a series of laboratory thermal alteration experiments and to use these diagnostic organic molecules to investigate their distribution and cycling in the Orca Basin, a well studied anoxic hypersaline basin in the Gulf of Mexico. %%% Objectives of the proposed study are (1) to investigate the alteration of isopranyl ether-linked lipids in the environment by using laboratory heating experiments combined with analysis of kerogen cleavage products to simulate diagenetic processes, (2) to examine the distribution of archaebaterial ether-linked lipids in the Orca Basin, including the overlying water, halocline, brine, surface sediments and selected DSDP sediments, and (3) to combine information on the distribution of archaebacterial ether lipids in the Orca Basin with data obtained from laboratory thermal alteration studies to eluciate the diagenetic pathways of archaebacterial ether lipds in the environment. Results of this study will provide a basis for investigating microbial ecology in the Orca Basin and may also serve as a model for other marine anoxic or hypersaline systems.

在高盐度、高温、低pH值或极端缺氧环境的海洋系统中，古细菌（包括产甲烷菌、极端嗜盐菌和热嗜酸菌）在有机碳的循环中起主导作用。异丙基甘油醚最近被认为是识别和区分古细菌的一个特征形态特征。为了利用这些化合物作为地质分子标记物，首先有必要了解它们在环境中的循环。Van Vleet博士建议使用一系列实验室热蚀变实验来研究这些化合物的潜在成岩蚀变产物，并使用这些诊断性有机分子来研究它们在Orca盆地的分布和循环。墨西哥湾一个被充分研究过的缺氧高盐盆地。本研究的目的是：(1)通过实验室加热实验结合干酪根裂解产物分析来模拟成岩作用，研究异丙烯醚连接的脂类在环境中的变化(2)研究Orca盆地中古细菌醚连接脂质的分布，包括上覆水、盐斜、盐水、地表沉积物和选定的DSDP沉积物；(3)结合Orca盆地古细菌醚类脂的分布信息和实验室热蚀变研究数据，阐明环境中古细菌醚类脂的成岩途径。本研究结果将为研究虎鲸盆地的微生物生态学提供基础，也可作为其他海洋缺氧或高盐系统的模型。