Duzdevich Daniel, Nisler Collin, Petkowski Janusz J, Bains William, Kaminsky Caroline K, Szostak Jack W, Seager Sara
Department of Chemistry, Searle Chemistry Laboratory, The University of Chicago, Chicago, Illinois, USA.
Freiburg Institute for Advanced Studies, Albert-Ludwigs-Universität Freiburg, Freiburg im Breisgau, Germany.
Astrobiology. 2025 Apr;25(4):270-283. doi: 10.1089/ast.2024.0124. Epub 2025 Mar 26.
Venus has become a target of astrobiological interest because it is physically accessible to direct exploration, unlike exoplanets. So far this interest has been motivated not by the explicit expectation of finding life but rather by a desire to understand the limits of biology. The venusian surface is sterilizing, but the cloud deck includes regions with temperatures and pressures conventionally considered compatible with life. However, the venusian clouds are thought to consist of concentrated sulfuric acid. To determine if any fundamental features of life as we understand them here on Earth could in principle exist in these extreme solvent conditions, we tested several simple lipids for resistance to solvolysis and their ability to form structures in concentrated sulfuric acid. We find that single-chain saturated lipids with sulfate, alcohol, trimethylamine, and phosphonate head groups are resistant to sulfuric acid degradation at room temperature. Furthermore, we find that they form stable higher-order structures typically associated with lipid membranes, micelles, and vesicles. Finally, results from molecular dynamics simulations suggest a molecular explanation for the observed robustness of the lipid structures formed in concentrated sulfuric acid. We conclude with implications for the study of Venus as a target of experimental astrobiology.
金星已成为天体生物学关注的目标，因为与系外行星不同，它在物理上便于直接探索。到目前为止，这种关注并非出于发现生命的明确期望，而是源于理解生物学极限的愿望。金星表面不适合生命存在，但云层中有一些区域的温度和压力通常被认为与生命相容。然而，金星云层被认为由浓硫酸组成。为了确定我们在地球上所理解的生命的任何基本特征在这些极端溶剂条件下原则上是否可能存在，我们测试了几种简单脂质对溶剂分解的抗性以及它们在浓硫酸中形成结构的能力。我们发现，带有硫酸根、醇、三甲胺和膦酸酯头部基团的单链饱和脂质在室温下对硫酸降解具有抗性。此外，我们发现它们形成了通常与脂质膜、胶束和囊泡相关的稳定高阶结构。最后，分子动力学模拟结果为浓硫酸中形成的脂质结构的观察到的稳定性提供了分子解释。我们最后讨论了将金星作为实验天体生物学目标进行研究的意义。
