Pearson A, Huang Z, Ingalls A E, Romanek C S, Wiegel J, Freeman K H, Smittenberg R H, Zhang C L
Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA 02138, USA.
Appl Environ Microbiol. 2004 Sep;70(9):5229-37. doi: 10.1128/AEM.70.9.5229-5237.2004.
Glycerol dialkyl glycerol tetraethers (GDGTs) are core membrane lipids of the Crenarchaeota. The structurally unusual GDGT crenarchaeol has been proposed as a taxonomically specific biomarker for the marine planktonic group I archaea. It is found ubiquitously in the marine water column and in sediments. In this work, samples of microbial community biomass were obtained from several alkaline and neutral-pH hot springs in Nevada, United States. Lipid extracts of these samples were analyzed by high-performance liquid chromatography-mass spectrometry and by gas chromatography-mass spectrometry. Each sample contained GDGTs, and among these compounds was crenarchaeol. The distribution of archaeal lipids in Nevada hot springs did not appear to correlate with temperature, as has been observed in the marine environment. Instead, a significant correlation with the concentration of bicarbonate was observed. Archaeal DNA was analyzed by denaturing gradient gel electrophoresis. All samples contained 16S rRNA gene sequences which were more strongly related to thermophilic crenarchaeota than to Cenarchaeum symbiosum, a marine nonthermophilic crenarchaeon. The occurrence of crenarchaeol in environments containing sequences affiliated with thermophilic crenarchaeota suggests a wide phenotypic distribution of this compound. The results also indicate that crenarchaeol can no longer be considered an exclusive biomarker for marine species.
甘油二烷基甘油四醚（GDGTs）是泉古菌的核心膜脂。结构独特的GDGT类异戊二烯古菌醇已被提议作为海洋浮游I群古菌的分类学特异性生物标志物。它在海洋水柱和沉积物中普遍存在。在这项研究中，微生物群落生物质样本取自美国内华达州的几个碱性和中性pH值的温泉。这些样本的脂质提取物通过高效液相色谱 - 质谱联用仪和气相色谱 - 质谱联用仪进行分析。每个样本都含有GDGTs，其中包括类异戊二烯古菌醇。内华达州温泉中古菌脂质的分布似乎与温度无关，这与在海洋环境中观察到的情况不同。相反，观察到与碳酸氢盐浓度存在显著相关性。通过变性梯度凝胶电泳分析古菌DNA。所有样本都含有16S rRNA基因序列，这些序列与嗜热泉古菌的相关性比与海洋非嗜热泉古菌共生嗜泉古菌的相关性更强。在含有与嗜热泉古菌相关序列的环境中类异戊二烯古菌醇的出现表明该化合物具有广泛的表型分布。结果还表明，类异戊二烯古菌醇不能再被视为海洋物种的专属生物标志物。
