Hydrostatic pressure is the universal key driver of microbial evolution in the deep ocean and beyond
Hydrostatic pressure is the universal key driver of microbial evolution in the deep ocean and beyond
复制标题
静水压力是深海及其他海域微生物进化的普遍关键驱动力
DOI：
10.1111/1758-2229.12915
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发表时间：
2021
影响因子：
3.3
通讯作者：
Fengping Wang
中科院分区：
文献类型：
--
作者：
Xiang Xiao;Yu Zhang;Fengping Wang
海洋覆盖了大约70%的地球表面，微生物占海洋生物量的90%，被认为是海洋中基本元素循环(如碳循环)的重要“隐藏”驱动因素(Karl，2007；Salazar和Sunagawa，2017)。尽管公众--甚至许多科学家--认为海洋是统一、稳定的水系，但海洋包含不同的环境，包括极端环境，如缺氧区、低营养开阔海洋、极地水域、深海、热液喷口、冷渗漏等，在这些环境中，特定的微生物群落已经演变(图1)。静水压力影响生活在海洋深处的生物的生理，就体积而言，海洋是生物圈最大的栖息地(1.3×1018立方米)(惠特曼等人，1998年)。虽然传统的生物海洋学研究更多地集中在海洋的光区，但由于深海工程技术的进步和分子生物学，特别是下一代DNA测序技术的快速发展，现在越来越多的人关注黑暗的深海。深海是指深度大于1000米，对应的静水压力大于10兆帕的海域。对于深海和地下环境中微生物群落的组成和分布的了解正在积累；例如，发现热液喷口烟囱中的主要功能群是嗜热的硫代谢微生物，如热球菌、热球菌和表变态杆菌，并且发现微生物群落在喷口停止后转向代谢铁硫矿物的群落(Hou等人，2020)，表明能源是微生物群落转变的驱动力。地下微生物被证明具有新陈代谢的灵活性，这有助于它们在能源匮乏的环境中生存(Li等人，2020)。各种环境因素，如温度、盐度、营养物质和化学反应物(电子供体和电子受体)，已经被调查，以了解它们对深海微生物生长的作用，以及一些因素被证明是塑造群落结构甚至微生物群进化的关键因素。尽管高静水压力(HHP)是海洋和次表层最常见的环境因素(图1)，但它与其他环境因素对微生物群(结构、功能和演化)的独立和联合影响从未被系统地调查和了解。因此，我们在这里呼吁科学界特别关注这个主要存在但大多被忽视的环境参数，即HHP，及其在塑造微生物生理学、群落结构和进化中的作用。HHP对细胞生理学和细胞学行为有深远的影响，包括转录、翻译、膜组成、多聚体蛋白组合、蛋白质结构和细胞运动，这些已经在压敏模型生物中进行了研究，如
Oceans cover approximately 70% of the Earth’s surface, and microbes comprise 90% of the ocean biomass and are regarded as an important ‘hidden’driver of essential elemental cycling, such as carbon cycling, in the oceans (Karl, 2007; Salazar and Sunagawa, 2017). Although the general public–even many scientists–think of the oceans as unified, stable water systems, they contain varied environments, including extreme environments such as oxygen-deficient zones, oligotrophic open ocean, polar water regions, deep ocean, hydrothermal vents, cold seeps, and so on, where specific microbial communities have evolved (Fig. 1). Hydrostatic pressure influences the physiology of organisms living at depth in the oceans, which is the largest habitat of the biosphere in terms of volume (1.3× 1018 m3)(Whitman et al., 1998). While traditional biological oceanographic research focuses more on the photic zone of the ocean, more attention is now being paid to the dark deep ocean due to the advancement of deep-ocean engineering technologies and the rapid progress of molecular biology, particularly next-generation DNA sequencing technologies. The deep ocean refers to those ocean waters with a depth greater than 1000 m, corresponding to a hydrostatic pressure of higher than 10 MPa. Knowledge of the composition and distribution of the microbiome in the deep ocean and subsurface environments is accumulating; for instance, mostly thermophilic, sulfur-metabolizing microbes, such as Thermoccoccus, Pyrococcus, and Episilonproteobacteria, are found to be the major functional groups in the hot fluid venting hydrothermal vent chimneys, and the microbial community has been discovered to shift to a community metabolizing iron–sulfur minerals after the venting ceased (Hou et al., 2020), indicating energy source is the driving force behind the microbiome shift. Microbes in the subsurface are shown to have metabolic flexibility, which helps them survive in energy-deficient environments (Li et al., 2020). Various environmental factors, such as temperature, salinity, nutrients, and chemical reactants (electron donors and electron acceptors), have been investigated to understand their roles on deep sea microbial growth, and some factors shown to be critical in shaping community structure and even the evolution of the microbiome. Although high hydrostatic pressure (HHP) is the most common environmental factor in the ocean and subsurface (Fig. 1), its independent and joint effects with other environmental factors on microbiomes (structure, function, and evolution) have never been systematically investigated and understood. Therefore, here we call for the scientific community to give special attention to this largely present but mostly ignored environmental parameter, ie, HHP, and its roles in shaping microbial physiology, community structure, and evolution. HHP has profound effects on cellular physiology and cytological behaviour, including transcription, translation, membrane compositions, multimeric protein assemblages, protein structure, and cellular motility, which have been studied in piezosensitive model organisms like