Heat Stress Dictates Microbial Lipid Composition along a Thermal Gradient in Marine Sediments.
Heat Stress Dictates Microbial Lipid Composition along a Thermal Gradient in Marine Sediments.
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热应激决定了沿海洋沉积物中热梯度的微生物脂质组成。
DOI：
10.3389/fmicb.2017.01550
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发表时间：
2017
影响因子：
5.2
通讯作者：
Bühring SI
中科院分区：
文献类型：
--
作者：
Sollich M;Yoshinaga MY;Häusler S;Price RE;Hinrichs KU;Bühring SI
温度对微生物种群施加一级控制，微生物种群不断调整其细胞膜脂质的流动性和渗透性，以最大限度地减少离子扩散穿过膜的能量损失。液相色谱与质谱联用技术的分析进展使人们能够在温泉、热液喷口和深层地下海洋沉积物等极端环境中检测到令人惊叹的细菌和古生菌脂质多样性。在这里，我们调查了18至101°C的海洋沉积物场的温度梯度，并测试了细胞膜脂质为热胁迫下古细菌和细菌的生物能量学提供主要生化基础的假设。本文介绍了一个详细的脂质组学方法，重点是膜脂质的结构-功能。这里分析的膜脂质包括细菌的极性脂质以及古细菌的极性和核心脂质。反映低渗透性的醚连接类异戊二烯，我们发现，古生菌极性脂质一般占主导地位的细菌脂质在深层的沉积物的热液流体的影响。对古细菌和细菌脂质的仔细研究揭示了膜的困境：不仅低渗透性，而且增加膜的流动性是热应力下微生物膜节能的统一属性。例如，细菌脂肪酸由更长的链长和更高的不饱和度组成，而古细菌在升高的沉积物温度下通过引入额外的甲基来修饰它们的四醚。这是可能的，这些配置朝向更流化的膜在升高的温度下被抵消的古菌糖脂和细菌鞘脂的高丰度，这可能会降低膜渗透性通过强分子间氢键。我们的研究结果提供了一个新的角度来解释膜脂的结构和功能，使古细菌和细菌在热液系统中生存和生长。
Temperature exerts a first-order control on microbial populations, which constantly adjust the fluidity and permeability of their cell membrane lipids to minimize loss of energy by ion diffusion across the membrane. Analytical advances in liquid chromatography coupled to mass spectrometry have allowed the detection of a stunning diversity of bacterial and archaeal lipids in extreme environments such as hot springs, hydrothermal vents and deep subsurface marine sediments. Here, we investigated a thermal gradient from 18 to 101°C across a marine sediment field and tested the hypothesis that cell membrane lipids provide a major biochemical basis for the bioenergetics of archaea and bacteria under heat stress. This paper features a detailed lipidomics approach with the focus on membrane lipid structure-function. Membrane lipids analyzed here include polar lipids of bacteria and polar and core lipids of archaea. Reflecting the low permeability of their ether-linked isoprenoids, we found that archaeal polar lipids generally dominate over bacterial lipids in deep layers of the sediments influenced by hydrothermal fluids. A close examination of archaeal and bacterial lipids revealed a membrane quandary: not only low permeability, but also increased fluidity of membranes are required as a unified property of microbial membranes for energy conservation under heat stress. For instance, bacterial fatty acids were composed of longer chain lengths in concert with higher degree of unsaturation while archaea modified their tetraethers by incorporation of additional methyl groups at elevated sediment temperatures. It is possible that these configurations toward a more fluidized membrane at elevated temperatures are counterbalanced by the high abundance of archaeal glycolipids and bacterial sphingolipids, which could reduce membrane permeability through strong intermolecular hydrogen bonding. Our results provide a new angle for interpreting membrane lipid structure-function enabling archaea and bacteria to survive and grow in hydrothermal systems.
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影响因子：
3.4
作者：
Baba, T;Minamikawa, H;Handa, T
通讯作者：
Handa, T
影响因子：
3.9
作者：
Botz, R;Stuben, D;Faber, E
通讯作者：
Faber, E
影响因子：
2.8
作者：
Aliani, S;Meloni, R;Dando, PR
通讯作者：
Dando, PR
影响因子：
3
作者：
Bradley, Alexander S.;Fredricks, Helen;Summons, Roger E.
通讯作者：
Summons, Roger E.
DOI：
10.1073/pnas.1505034112
发表时间：
2015-06-23
影响因子：
11.1
作者：
Carini, Paul;Van Mooy, Benjamin A. S.;Giovannoni, Stephen J.
通讯作者：
Giovannoni, Stephen J.