The emergence of life's earliest proteins and enzymes remains a captivating enigma, especially considering the constraints of Earth's prebiotic era. In this study, we explore the potential of prebiotically plausible peptides, which could have been the building blocks of life's first complex structures. These peptides, composed of a limited set of amino acids, exhibit remarkable self-assembly properties. Despite the scarcity of basic amino acids like lysine, arginine, and histidine, the acidic amino acids were more abundant, suggesting a different set of chemical interactions. This shift in amino acid availability might have influenced the formation of early peptides, which were likely short, random sequences without genetic templates. The key question is: could these simple, unevolved peptides have already provided the necessary biological organization? Our findings reveal a surprising capacity for self-organization. Random peptides, made solely from prebiotically plausible amino acids, spontaneously fold and assemble into stable, soluble β-sheet–rich nanostructures. This discovery is significant because it suggests that even the simplest, earliest peptides could have served as the initial scaffolds for molecular interactions, potentially paving the way for the emergence of biological complexity. This research, published in [https://www.biorxiv.org/content/10.1101/2025.11.09.687475v1], opens up exciting possibilities for understanding the origins of life and the role of self-assembly in the early evolution of biological systems.
