On the lack of evolutionary continuity between prebiotic peptides and extant enzymes.
On the lack of evolutionary continuity between prebiotic peptides and extant enzymes.
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关于益生元肽和现存酶之间缺乏进化连续性。
DOI：
10.1039/c6cp00793g
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发表时间：
2016
期刊：
影响因子：
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通讯作者：
A. Lazcano
中科院分区：
文献类型：
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作者：
L. Raggi;J. Bada;A. Lazcano
对声称模拟益生菌小肽和多肽的性质作为可能先于蛋白质的聚合物的模型的实验的意义进行了批判性的讨论。正如这里所讨论的，这些实验中的大多数只基于可能存在于生前环境中的较大一组氨基酸中的一小部分，得到了实验模拟和碳质球粒陨石中报告的有机化合物谱系的支持。用小肽进行的模型实验可能会为有助于产生化学环境的过程提供一些见解，这些化学环境导致信息低聚物的出现，但不是蛋白质的起源。大量间接证据表明，在细胞进化的早期阶段，催化RNA在蛋白质合成的起源中发挥了关键作用，这意味着遗传密码和蛋白质生物合成的出现不再是生命起源的同义词。因此，关于在潜在的益生菌条件下非生物合成小分子催化肽的报道并没有提供关于三联体编码蛋白质生物合成的信息，但在某些情况下可以作为理解最早蛋白质性质的模型。
The significance of experiments that claim to simulate the properties of prebiotic small peptides and polypeptides as models of the polymers that may have preceded proteins is critically addressed. As discussed here, most of these experiments are based only on a small number of a larger set of amino acids that may have been present in the prebiotic environment, supported by both experimental simulations and the repertoire of organic compounds reported in carbonaceous chondrites. Model experiments with small peptides may offer some insights into the processes that contributed to generate the chemical environment leading to the emergence of informational oligomers, but not to the origin of proteins. The large body of circumstantial evidence indicating that catalytic RNA played a key role in the origin of protein synthesis during the early stages of cellular evolution implies that the emergence of the genetic code and of protein biosynthesis are no longer synonymous with the origin of life. Hence, reports on the abiotic synthesis of small catalytic peptides under potential prebiotic conditions do not provide information on the origin of triplet encoded protein biosynthesis, but in some cases may serve as models to understand the properties of the earliest proteins.