GDGT是一种古菌脂类化合物,主要来源于海洋中的四醚类脂。在早期生命演化研究中,GDGT环化指数有着重要的基础性影响。 GDGT环化指数基于环化GDGT分子作为古海洋温度的代用指标(例如TEX86)。TEX86是一种用于重建古海洋表面温度的指标,通过分析海洋沉积物中的GDGT分子组成,可以推断出古海洋的温度变化。然而,在生物机理...
甘油二烷基甘油四醚(GDGT)是古菌细胞膜脂质的典型代表,广泛应用于生态学和地球化学研究,尤其在古环境重建领域,如TEX86指标反演古海水温度。近年来,一类特殊的GDGT在环境样品和古菌培养样品中被发现,其在GDGT的烷基侧链的C-13位置发生...
然而,环化的GDGT在古菌体内如何合成,这一问题从GDGT发现四十多年以来一直成谜。解决这一问题的重要性体现在两个方面:(1)古菌如何进化出特殊的细胞膜生物合成通路以适应各种极端的生存环境,这对于早期生命演化的研究有着重要的基础性的影响;(2)基于环化GDGT分子作为古海洋温度的代用指标(例如TEX86),我们需要知道在...
However, in the hypolimnion where oxygen was depleted for most of the study period, we found that TEX86 co-varied with DO. This further confirms previous claims with seasonal field data that the sedimentary TEX86 LST signal may be confounded by DO conditions. Consequently, the application of...
GDGT distribution in a stratified lake and implications for the application of TEX86 in paleoenvironmental reconstructions. GDGT distribution in a stratified lake and implications for the application of TEX86 in paleoenvironmental reconstructions.doi:10.1038/srep34465... Zhaohui,Zhang,H Rienk,... - ...
TEX86MBT/CBTBITChinese marginal seasArchaeal and bacterial glycerol dialkyl glycerol tetraethers(GDGTs) play a unique role in discerning the biogeochemical processes and climate change in terrestrial(e.g. soil, peat, stalagmites, lakes, rivers, hot springs) and marine environments. Organic proxies ...
【摘要】甘油双烷基甘油四醚(Glycerol Dialkyl Glycerol Tetraethers,GDGTs)是古菌和细菌等微生物细胞膜脂的主要组成部分,包括类异戊二烯GDGTs和支链GDGTs两大类.类异戊二烯GDGTs主要来自海洋泉古菌,其分子中环结构的数目随温度变化而变化.描述类异戊二烯GDGTs相对分布的TEX86指标与表层海水温度(SST)和湖泊表面温度(LST)之间...
类异戊二烯甘油二烷基甘油四醚类化合物(isoGDGTs)是古菌微生物的特征脂类标志物,由这组化合物构造出的TEX86温标在海水古温度重建中得到了广泛应用.本文调查了珠江口及... 郭威,叶丰,贾国东 - 《海洋学报》 被引量: 0发表: 2017年 百余年来珠江口及邻近西部海域有机碳来源及其埋藏记录 余年沉积历史的柱状样进...
The Branched Isoprenoid Tetraether (BIT) index is the ratio of branched GDGTs (brGDGTs) to isoGDGTs which can be used to identify lakes with a high proportion of brGDGTs and thus where the TEX86 index will be unreliable (e.g., BIT>0.5; Hopmans et al., 2004, Weijers et al., 2006,...
Suspended particulate matter (SPM) BIT TEX86 16S rRNA gene East Africa Lake Chala 1. Introduction Lipid biomarkers in lake sediments are increasingly used to reconstruct past environmental changes such as temperature, rainfall and vegetation dynamics in the lake's catchment (e.g., Castañeda and ...