Prebiotic condensation through wet-dry cycling regulated by deliquescence
Prebiotic condensation through wet-dry cycling regulated by deliquescence
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DOI：
10.1038/s41467-019-11834-1
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发表时间：
2019-10-04
影响因子：
16.6
通讯作者：
Bracher, Paul J.
中科院分区：
文献类型：
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作者：
Campbell, Thomas D.;Febrian, Rio;Bracher, Paul J.
干湿循环被广泛认为是一种在益生菌条件下驱动缩合反应以产生预期的生物聚合物混合物的方法。对这种模式的批评是，它依赖于不可预测的补水事件，如暴雨。在这里，我们报告了潮解矿物在反复的干湿循环中调节甘氨酸齐聚的能力。反应混合物在高温下蒸发至干燥，并在低温下自发地重新获得水蒸气形成水溶液。潮解混合物可以促进齐聚反应的产率比非潮解对照高十倍以上。易潮解的混合物严格控制其水分含量，这是至关重要的，因为太少的水阻止了反应物的溶解，而太多的水有利于水解而不是缩合。该模型还提出了生命进化为有利于钾的富集化的一个潜在原因：因此，生命系统可以获得并保留足够的水，作为生化反应的溶剂。
Wet-dry cycling is widely regarded as a means of driving condensation reactions under prebiotic conditions to generate mixtures of prospective biopolymers. A criticism of this model is its reliance on unpredictable rehydration events, like rainstorms. Here, we report the ability of deliquescent minerals to mediate the oligomerization of glycine during iterative wet-dry cycles. The reaction mixtures evaporate to dryness at high temperatures and spontaneously reacquire water vapor to form aqueous solutions at low temperatures. Deliquescent mixtures can foster yields of oligomerization over ten-fold higher than nondeliquescent controls. The deliquescent mixtures tightly regulate their moisture content, which is crucial, as too little water precludes dissolution of the reactants while too much water favors hydrolysis over condensation. The model also suggests a potential reason why life evolved to favor the enrichment of potassium: so living systems could acquire and retain sufficient water to serve as a solvent for biochemical reactions.