Survival of the fewest: Microbial dormancy and maintenance in marine sediments through deep time.
Survival of the fewest: Microbial dormancy and maintenance in marine sediments through deep time.
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DOI：
10.1111/gbi.12313
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发表时间：
2019-01
期刊：
影响因子：
3.7
通讯作者：
LaRowe DE
中科院分区：
文献类型：
--
作者：
Bradley JA;Amend JP;LaRowe DE
众所周知，埋藏在海洋沉积物中的微生物在地质时间尺度上可以忍受饥饿。然而，这些微生物如何科普长期的能量限制的机制是未知的，因此尚未在定量框架中捕获。在这里，我们提出了一种新的数学模型，该模型考虑了（a）微生物的活性和休眠状态之间的生理转变，（B）这些阶段之间对维持能力的不同要求，以及（c）来源的灵活性（即，能量的来源）来自于外源性和内源性的catalysts。该模型适用于贫营养南太平洋环流的沉积物，在那里微生物忍受了数千万年的超低能量通量。模式模拟结果与细胞碳和有机碳浓度的测量结果吻合较好，并解释为：（a）南太平洋环流沉积物中不利的微生物生境触发了快速死亡和向休眠的过渡;（B）生物量增长最小，有机碳消耗主要由支持维持活动的categories而不是新的生物量合成;（c）微生物为维持活动所消耗的有机碳量约相当于其每年碳生物量的2%;（d）微生物必须完全依赖外源性而非内源性催化剂才能在南太平洋环流沉积物中长期存在。这使我们得出这样的结论：在贫营养条件下，生物体的适应性取决于其生存能力，而不是生长能力。这个模型框架的设计是灵活的，适用于其他网站和栖息地，从而作为一个新的定量工具，以确定在任何环境中的可居住性和生命的最终限制。
Microorganisms buried in marine sediments are known to endure starvation over geologic timescales. However, the mechanisms of how these microorganisms cope with prolonged energy limitation is unknown and therefore yet to be captured in a quantitative framework. Here, we present a novel mathematical model that considers (a) the physiological transitions between the active and dormant states of microorganisms, (b) the varying requirement for maintenance power between these phases, and (c) flexibility in the provenance (i.e., source) of energy from exogenous and endogenous catabolism. The model is applied to sediments underlying the oligotrophic South Pacific Gyre where microorganisms endure ultra‐low fluxes of energy for tens of millions of years. Good fits between model simulations and measurements of cellular carbon and organic carbon concentrations are obtained and are interpreted as follows: (a) the unfavourable microbial habitat in South Pacific Gyre sediments triggers rapid mortality and a transition to dormancy; (b) there is minimal biomass growth, and organic carbon consumption is dominated by catabolism to support maintenance activities rather than new biomass synthesis; (c) the amount of organic carbon that microorganisms consume for maintenance activities is equivalent to approximately 2% of their carbon biomass per year; and (d) microorganisms must rely solely on exogenous rather than endogenous catabolism to persist in South Pacific Gyre sediments over long timescales. This leads us to the conclusion that under oligotrophic conditions, the fitness of an organism is determined by its ability to simply stay alive, rather than to grow. This modelling framework is designed to be flexible for application to other sites and habitats, and thus serves as a new quantitative tool for determining the habitability of and an ultimate limit for life in any environment.
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影响因子：
13.6
作者：
Danovaro R;Molari M;Corinaldesi C;Dell'Anno A
通讯作者：
Dell'Anno A
影响因子：
4.6
作者：
Braun S;Mhatre SS;Jaussi M;Røy H;Kjeldsen KU;Pearce C;Seidenkrantz MS;Jørgensen BB;Lomstein BA
通讯作者：
Lomstein BA
DOI：
10.1073/pnas.0600035103
发表时间：
2006-03-07
影响因子：
11.1
作者：
Biddle, JF;Lipp, JS;Hinrichs, KU
通讯作者：
Hinrichs, KU
影响因子：
3.7
作者：
Bienhold C;Zinger L;Boetius A;Ramette A
通讯作者：
Ramette A
影响因子：
56.9
作者：
Gonzalez-Pastor, JE;Hobbs, EC;Losick, R
通讯作者：
Losick, R