Prebiotic template-directed peptide formation mediated by polyphosphates and peptide promoters

Abstract

Minerals have long been recognized for their role in promoting molecular self-assembly in prebiotic environments by serving as insoluble inorganic scaffolds. However, it remains unclear whether soluble inorganic scaffold molecules, such as polyphosphates, also possess the ability to drive the assembly of small molecules. In this study, carbonyldiimidazole (CDI) was used as a chemical activator in combination with polyphosphates (polyP) to investigate the polymerization behavior of the alkaline amino acid arginine (Arg, R). We found that polyP can act as templates to guide the formation of Arg peptides through electrostatic interactions. Cationic short peptides, specifically RRR and RER, can serve as primers to promote the formation of Arg-containing peptides. Chiral competition experiments using ¹⁵N₄-labeled L-Arg as a tracer have shown that cationic short peptides possess an intrinsic preference for homochirality, which can be amplified by polyP through a synergistic enhancement effect. Our findings provide novel insights into the formation mechanism of Arg-rich peptides and the origin of homochirality.