Peptides at vesicle and mineral prebiotic interfaces
The origin of life likely involved a complex interplay between organic molecules and mineral surfaces, yet the molecular details of these interactions remain poorly understood. Over recent decades, considerable research has focused on the individual roles of key biomolecules - such as RNA, lipids, and proteins - in early abiogenesis. However, this reductionist view offers only a partial picture because the emergence of life likely involved networks of molecular interactions that collectively shaped early functional assemblies. In this study, we examine the ability of peptides - arguably one of the most abundant early polymers - to interact with mineral surfaces and lipid vesicles, prebiotic interfaces and compartments. Using peptide libraries constructed from either prebiotically plausible or contemporary amino acids, we demonstrate that while acidic residues drive peptide binding to mineral surfaces (such as fluorapatite, studied here), the inclusion of arginine - a basic residue that may have been accessible in specific prebiotic environments - synergistically enhances the mobilization of bioavailable phosphate from geological reservoirs. Furthermore, we observe a functional divergence in vesicle interactions: while prebiotic alphabets promote dynamic membrane behaviours such as budding, libraries with late canonical amino acids can help preserve vesicle integrity against salt-induced collapse. Our finding supports the view that interactions with peptides can elicit changes in both prebiotic minerals and vesicles, underscoring the importance of studying these systems collectively.