Interstep compatibility of a model for the prebiotic synthesis of RNA consistent with Hadean natural history

• 成果类型: Article
• 署名作者: Hirakawa, Yuta; Kim, Hyo-Joong; Furukawa, Yoshihiro; Abraham, Clay; Peng, Tzu-Wei; Biondi, Elisa; Benner, Steven A.
• 署名单位: Tohoku University; Japan Agency for Marine-Earth Science & Technology (JAMSTEC)
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.2516418122
• 发表日期: 2025-12-23
• 页码: e2516418122
• 关键词: prebiotic chemistry; Hadean geology; mars; rna; Discontinuous Synthesis Model; ISUA SUPRACRUSTAL BELT; CONDENSED PHOSPHATES; BORATE COMPLEXES; origin; LIFE; phosphorylation; RIBOSE; GLYCOLALDEHYDE; formaldehyde; TOURMALINE

摘要

Models for prebiotic syntheses often have many steps, each separately validated by laboratory experiments. The challenge then asks whether these steps work together in natural geological environments, absent human intervention. Here, we analyze a proposed to be the first informational molecule to support Darwinian evolution, and life, on Earth and/or Mars. DSM requires that borate in multiple steps guide the formation of pentoses from simple carbohydrates and control phosphorylation, in all cases by binding adjacent HO- groups on key intermediates. However, adjacent HO- groups must react in two other steps, which borate might inhibit. Experiments here show that borate does not inhibit these two other steps, but rather facilitates them. This makes the six- step DSM a no human intervention route from simple precursors (1 to 3 carbons, 0 to 2 nitrogens) to oligomeric RNA with predominately 3',5'- linkages at least 6 nucleotides long, but possibly much longer. The process i) exploits privileged chemistry in ii) intermittently irrigated aquifers constrained by basalt that iii) have borate iv) above a redox- neutral mantle v) having access to an atmosphere transiently reduced by a Vesta- sized impactor. In a possible coincidence, some molecular clocks date the divergence of the three kingdoms of life on Earth (4.2 Ga), and ca. 200 Mya before isotopically light carbon is reported in zircons dated at 4.1 Ga. This carbon may be the oldest trace of life ever proposed.