Stepwise evolution of nonliving to living chemical systems.
Stepwise evolution of nonliving to living chemical systems.
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无生命化学系统逐步演化为生命化学系统。
DOI：
10.1023/b:orig.0000029880.76881.f5
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
Lindahl,PaulA
中科院分区：
文献类型：
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作者：
Lindahl,PaulA
一个无生命的化学系统可能已经转化为一个生命系统的步骤进行了描述和讨论，假设一般特征的Wächtershäuser的化学自养表面理论的起源生命。环境物种，如CO2和H2S被认为已经反应形成了一个准稳态的金属结合的中间体（CH 3-M），缓慢衰减成废物（CH 4）。不可预测的分散反应扩展了系统，包括表面结合形式的柠檬酸循环中间体（草酰乙酸→柠檬酸）。进一步的反应产生了一个自催化体系，其中原料以指数速率转化到该体系中。系统进化出生命系统的关键特征（蛋白质、膜、蛋白质、核酸等），并将这些关键特征转化为生物系统的关键特征。using运用two related相关mechanisms机制called叫graftingandwaste-conversion移植.这种生命系统是从较难识别的类型（以自催化扩散、分散化、边界不明确等为特征）转变而来的。转化为更易识别的（由膜包裹，由单分子基因组控制等）通过细胞分裂周期自我复制，并可以通过标准的基于基因的达尔文机制进化。由此产生的系统被视为具有由三个连接的自催化子反应组成的自催化网络。
Steps by which a nonliving chemical system could have transformed into a living system are described and discussed, assuming general features of Wächtershäuser's chemo-autotrophic surface theory of the origin of life. Environmental species such as CO2and H2S are proposed to have reacted to form a quasi-steady state metal-bound intermediate (CH3-M) that slowly decayed into waste (CH4). Unpredictable dispersive reactions expanded the system to include surface-bound forms of the citric acid cycle intermediates (oxaloacetate → citrate). Further reaction yielded an autocatalytic system in which raw materials are converted into the system at exponential rates. Combinatorial dispersive reactions that improved the performance of this system were automatically selected and incorporated into it. Systems evolved critical features of living systems (proteins, membranes, proteins, nucleic acids, etc.) using two related mechanisms calledgraftingandwaste-conversion. Such living systems were transformed from less recognizable types (characterized by autocatalytic spreading, decentralization, poorly defined boundaries, etc.) into more recognizable ones (encapsulated by membranes, controlled by single-molecule genomes, etc.) that self-replicated by a cell division cycle and could evolve by the standard gene-based Darwinian mechanism. The resulting systems are viewed as having an autocatalytic network composed of three linked autocatalytic subreactions.