Key Laboratory of Submarine Geoscience, Second Institute of Oceanography, State Oceanic Administration, Hangzhou, 310012, China.
State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences (Wuhan), Wuhan, 430074, China.
Sci Rep. 2018 May 23;8(1):8060. doi: 10.1038/s41598-018-26166-1.
This study presents analysis of four chimney samples in terms of glycerol dialkyl glycerol tetraether lipids (GDGTs), representing different growing stages of sulfide chimneys at the Deyin hydrothermal field, the southern mid-Atlantic ridge. The modified Bligh-Dyer method was used for lipid extraction and purification. GDGTs were analyzed with an Agilent 1200 series liquid chromatograph and 6460A triple quadrupole mass spectrometer. Our results showed that the intact polar GDGTs were more abundant than the core GDGTs in the 4 samples. The intact polar isoprenoidal GDGT-0 was the dominant composition (>70% of isoprenoidal GDGTs), indicating input of thermophilic Euryarchaeota. Most branched GDGTs were likely originated from the in situ thermophilic bacteria. However, the intact polar GDGTs in the sample at the late growing stage was similar to that in normal marine sediments, suggesting that the archaea mainly came from the planktonic Thaumarchaeota input. Our results suggested that the ratio of H-GDGTs to iGDGTs could be considered as a proxy to differentiated growing stages of a chimney. This study shed light on how to assess hydrothermal venting and sulfide chimneys in deep marine environments with a biomarker method in terms of different groups of GDGTs.
本研究对德银热液场（南大西洋中脊）四个不同生长阶段硫化物烟囱的甘油二烷基甘油四醚脂（GDGTs）进行了分析。采用改良的布莱迪耶法进行脂质提取和纯化。使用安捷伦 1200 系列液相色谱仪和 6460A 三重四极杆质谱仪对 GDGTs 进行分析。结果表明，在 4 个样品中，完整极性 GDGTs 的含量高于核心 GDGTs。完整极性异戊二烯 GDGT-0 是主要成分（异戊二烯 GDGTs 的比例>70%），表明嗜热古菌的输入。大多数支链 GDGTs 可能来自原位嗜热细菌。然而，晚期生长阶段样品中的完整极性 GDGTs 与正常海洋沉积物中的 GDGTs 相似，表明古菌主要来自浮游态广古菌的输入。本研究结果表明，H-GDGTs 与 iGDGTs 的比值可以作为区分烟囱生长阶段的指标。本研究为利用不同 GDGTs 组分为深海环境中的热液喷口和硫化物烟囱提供了一种生物标志物方法。
