Heated gas bubbles enrich, crystallize, dry, phosphorylate and encapsulate prebiotic molecules

TL;DR

This study demonstrates how heated gas bubbles in water under thermal gradients could have facilitated the enrichment, crystallization, phosphorylation, and encapsulation of prebiotic molecules, supporting early molecular evolution.

Contribution

It reveals a novel mechanism by which gas bubbles in thermal gradients could have driven key prebiotic chemical processes on early Earth.

Findings

Gas bubbles enable cycling of molecules between dry and wet states.

Molecules accumulate at gas-water interfaces, boosting activity.

Prebiotic molecules form crystals, hydrogels, and vesicles within 30 minutes.

Abstract

Non-equilibrium conditions must have been crucial for the assembly of the first informational polymers of early life, but supporting their formation and continuous enrichment in a long-lasting environment. Here, we explore how gas bubbles in water subjected to a thermal gradient, a likely scenario within crustal mafic rocks on the early Earth, drive a complex, continuous enrichment of prebiotic molecules. NRA precursors, monomers, active ribozymes, oligonucleotides and lipids are shown to (1) cycle between dry and wet states, enabling the central step of RNA phosphorylation, (2) accumulate at the gas-water interface to drastically increase ribozymatic activity, (3) condense into hydrogels, (4) form pure crystals and (5) encapsulate into protecting vesicle aggregates that subsequently undergo fission. These effects occur within less than 30 min. The findings unite, in one location, the physical conditions that were crucial for the chemical emergence of biopolymers. They suggest that heated microbubbles could have hosted the first cycles of molecular evolution.