A common intermediate for prebiotic synthesis of proteins and nucleosides: a density functional theory (DFT) study on the formation of penta-coordinate phosphorus carboxylic–phosphoric mixed anhydride from N-phosphoryl amino acids

Abstract

N-phosphoryl amino acids (PAA) are a unique chemical species with many chemical reactivities and properties, including the ability to self-assemble into oligopeptides. Because of their chemical characteristics, they have been proposed as the common origin for both nucleic acids and proteins. In this paper, we discussed six intramolecular mixed carboxylic–phosphoric anhydrides (IMCPAs) as possible intermediates for the prebiotic synthesis of biopolymers from PAA. We also investigated the role of water molecules in the formation of IMCPA using density functional theory B3LYP quantum mechanical calculations at the 6-31G** and 6-311+G** levels. Our results showed that the energy barrier of IMCPA formation was reduced from 19.5 kcal mol −1 to 9.9 kcal mol −1 when water participation and solvent effects were considered. Thus, the direct participation of one water molecule and the bulk solvent effects both play important roles in the formation of IMCPA.