Nanda Jayanta, Rubinov Boris, Ivnitski Denis, Mukherjee Rakesh, Shtelman Elina, Motro Yair, Miller Yifat, Wagner Nathaniel, Cohen-Luria Rivka, Ashkenasy Gonen
Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva, 84105, Israel.
Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Howrah, 711103, India.
Nat Commun. 2017 Sep 5;8(1):434. doi: 10.1038/s41467-017-00463-1.
Biopolymer syntheses in living cells are perfected by an elaborate error correction machinery, which was not applicable during polymerization on early Earth. Scientists are consequently striving to identify mechanisms by which functional polymers were selected and further amplified from complex prebiotic mixtures. Here we show the instrumental role of non-enzymatic replication in the enrichment of certain product(s). To this end, we analyzed a complex web of reactions in β-sheet peptide networks, focusing on the formation of specific intermediate compounds and template-assisted replication. Remarkably, we find that the formation of several products in a mixture is not critically harmful, since efficient and selective template-assisted reactions serve as a backbone correction mechanism, namely, for keeping the concentration of the peptide containing the native backbone equal to, or even higher than, the concentrations of the other products. We suggest that these findings may shed light on molecular evolution processes that led to current biology.The synthesis of biopolymers in living cells is perfected by complex machinery, however this was not the case on early Earth. Here the authors show the role of non-enzymatic replication in the enrichment of certain products within prebiotically relevant mixtures.
活细胞中的生物聚合物合成通过一套精密的纠错机制得以完善，而在早期地球上进行聚合反应时，这种机制并不适用。因此，科学家们一直在努力寻找从复杂的前生物混合物中筛选和进一步扩增功能聚合物的机制。在此，我们展示了非酶复制在某些产物富集过程中的重要作用。为此，我们分析了β-折叠肽网络中的一个复杂反应网络，重点关注特定中间化合物的形成以及模板辅助复制。值得注意的是，我们发现混合物中几种产物的形成并非具有极大危害，因为高效且选择性的模板辅助反应充当了一种主干校正机制，也就是说，用于使含有天然主链的肽的浓度等于甚至高于其他产物的浓度。我们认为这些发现可能会为导致当前生物学的分子进化过程提供线索。活细胞中生物聚合物的合成通过复杂机制得以完善，但早期地球并非如此。在此，作者展示了非酶复制在与前生物相关混合物中某些产物富集过程中的作用。
