What is the significance of pH variability in the prebiotic synthesis of cyclic dipeptides on early Earth?

The study investigates the role of pH variability in the polymerization of biomolecules, specifically focusing on the formation of cyclic dipeptides from prolinamide and free amino acids under simulated early Earth conditions. Previous research has shown that the formation of cyclic dipeptides is influenced by pH, with different pH levels favoring different stages of the reaction.

From: "Local pH variability scenario: Prebiotic synthesis of cyclic dipeptides via prolinamide on the Hadean Earth", Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 651, 1 October 2024, 112402

The study demonstrates that pH variability, particularly between pH 7 and pH 11, significantly enhances the formation of cyclic dipeptides from prolinamide. This variability provides an effective route for the generation of cyclic dipeptides without the need for a catalyst, suggesting that fluctuating pH conditions in early Earth environments, such as those near volcanic pools, could have facilitated the prebiotic synthesis of these important biomolecules.