The Transformation by Catalysis of Prebiotic Chemical Systems to Useful Biochemicals: A Perspective Based on IR Spectroscopy of the Primary Chemicals: Solid-Phase and Water-Soluble Catalysts

Abstract

This study is a continuation of our research on understanding the possible chemical routes to the evolution of life on earth based on the “Selective Energy Transfer” (SET) theory. This theory identifies the specific vibrational mode of the catalyst that is in energy-resonance with a suitable vibrational mode of the reactant. In this way, energy is transferred from catalyst to reactant up to the energy of activation, making possible a particular chemical outcome. Then, we extend this model to the mostly unknown and highly complex environment of the hydrothermal vents, to speculate how prebiotic chemicals, necessary for the evolution of life, could have formed. It is to the credit of the SET theory that it can reflect the slight difference in the catalytic system that gives dramatically very different chemical outcome. It is shown, here, how in model laboratory experiments, methanol gives dimethyl ether (DME) in a 100% yield with Cu exchanged montmorillonite as the catalyst, or a very different product methyl formate (MF) in lower yields, with another Cu2+ ion-exchanged clay mineral (laponite) as the catalyst system. We also show, based on standard laboratory experiments, how COS (carbonyl sulfide) with a strong absorption band at 2079 cm−1 by itself and/or catalyzed by montmorillonite with strong Si-O-Si asymmetric vibration of 1040 cm−1 can react with alpha-amino acids to form alpha-amino acid thiocarbamate (AATC), which we feel could represent the most primitive analogue to coenzyme A (CoASH), a highly versatile bio-enzyme that is vital both for the metabolism and the synthesis of biochemicals in the living system. AATC itself may have undergone evolutionary developments through billions of years to transform itself into coenzyme A (CoASH) and its acetyl ester analogue acetyl coenzyme A (ACoA).