Piñeros William D, Tlusty Tsvi
Center for Soft and Living Matter, Institute for Basic Science (IBS), Ulsan, 44919, Korea.
Department of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Korea.
Nat Commun. 2022 Apr 26;13(1):2244. doi: 10.1038/s41467-022-29952-8.
Living systems have evolved to efficiently consume available energy sources using an elaborate circuitry of chemical reactions which, puzzlingly, bear a strict restriction to asymmetric chiral configurations. While autocatalysis is known to promote such chiral symmetry breaking, whether a similar phenomenon may also be induced in a more general class of configurable chemical systems-via energy exploitation-is a sensible yet underappreciated possibility. This work examines this question within a model of randomly generated complex chemical networks. We show that chiral symmetry breaking may occur spontaneously and generically by harnessing energy sources from external environmental drives. Key to this transition are intrinsic fluctuations of achiral-to-chiral reactions and tight matching of system configurations to the environmental drives, which together amplify and sustain diverged enantiomer distributions. These asymmetric states emerge through steep energetic transitions from the corresponding symmetric states and sharply cluster as highly-dissipating states. The results thus demonstrate a generic mechanism in which energetic drives may give rise to homochirality in an otherwise totally symmetrical environment, and from an early-life perspective, might emerge as a competitive, energy-harvesting advantage.
生命系统已经进化到能够利用复杂的化学反应回路高效地消耗可用能源，令人费解的是，这些反应严格限制在不对称手性构型上。虽然自催化已知会促进这种手性对称性破缺，但在更一般的可配置化学系统中，是否也可以通过能量利用诱导类似现象，是一个合理但未得到充分重视的可能性。这项工作在随机生成的复杂化学网络模型中研究了这个问题。我们表明，通过利用来自外部环境驱动的能源，手性对称性破缺可能会自发且普遍地发生。这种转变的关键是从非手性到手性反应的内在波动以及系统构型与环境驱动的紧密匹配，它们共同放大并维持不同的对映体分布。这些不对称状态通过从相应对称状态的陡峭能量转变出现，并作为高耗散状态急剧聚集。因此，结果证明了一种普遍机制，即能量驱动可能在原本完全对称的环境中产生同手性，从早期生命的角度来看，可能会作为一种竞争性的能量收集优势出现。
