Department of Cellular, Computational and Integrative Biology, University of Trento, Via Sommarive 9, 38123 Povo, Trentino, Italy.
Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton Alberta T6G 2G2, Canada.
ACS Nano. 2023 Dec 12;17(23):23772-23783. doi: 10.1021/acsnano.3c07706. Epub 2023 Dec 1.
There is currently no plausible path for the emergence of a self-replicating protocell, because prevalent formulations of model protocells are built with fatty acid vesicles that cannot withstand the concentrations of Mg needed for the function and replication of nucleic acids. Although prebiotic chelates increase the survivability of fatty acid vesicles, the resulting model protocells are incapable of growth and division. Here, we show that protocells made of mixtures of cyclophospholipids and fatty acids can grow and divide in the presence of Mg-citrate. Importantly, these protocells retain encapsulated nucleic acids during growth and division, can acquire nucleotides from their surroundings, and are compatible with the nonenzymatic extension of an RNA oligonucleotide, chemistry needed for the replication of a primitive genome. Our work shows that prebiotically plausible mixtures of lipids form protocells that are active under the conditions necessary for the emergence of Darwinian evolution.
目前，自我复制的原细胞的出现没有合理的途径，因为流行的模型原细胞的配方是用脂肪酸囊泡构建的，而这些囊泡无法承受核酸功能和复制所需的镁浓度。虽然前生物螯合物提高了脂肪酸囊泡的存活率，但由此产生的模型原细胞无法生长和分裂。在这里，我们表明，由环磷酰胺和脂肪酸混合物制成的原细胞可以在 Mg-柠檬酸盐存在的情况下生长和分裂。重要的是，在生长和分裂过程中原细胞保留了包裹的核酸，可以从周围环境中获取核苷酸，并与 RNA 寡核苷酸的非酶延伸兼容，这是原始基因组复制所必需的化学物质。我们的工作表明，在达尔文进化出现所需的条件下，原细胞可以由前生物合理的脂质混合物形成。
