The article, titled “NADH-mediated primordial synthesis of amino acids” and published on 14 February 2024 in Organic Chemistry Frontiers, discusses the enzyme-free reductive amination by Nicotinamide Adenine Dinucleotide (NADH) under prebiotic conditions, giving a plausible route to early amino acid synthesis. In the video below, postdoctoral researcher Dr. Javier Luis-Barrera from the Autonomous University of Madrid (UAM) explains how NADH, in the absence of enzymes and under mild prebiotic conditions, can facilitate the reductive amination of α-ketoacids to produce amino acids.

Key highlights of the paper include:

• Demonstrated enzyme-free reductive amination of α-ketoacids with NADH in ammonia/ammonium solution at pH 8, yielding amino acids under plausible prebiotic conditions.
• Alanine and glutamate formed in ~33–36% yield, while glycine showed poor yield due to NADH degradation; aspartate failed due to decarboxylation.
• Mechanistic evidence from NMR, MS, and UV–Vis reveals conversion of NADH → NAD⁺ and significant formation of ADP-ribose, especially with glyoxylate, suggesting cofactor degradation pathways.
• DFT calculations indicate a feasible energy landscape: First, hemiaminal formation and dehydration to an iminium intermediate (activation ~70 kJ/mol), then hydride transfer (activation ~86 kJ/mol). Overall, the process is exergonic (≈ –50 kJ/mol).
• Supports a chemoautotrophic protometabolism theory, suggesting NADH or simpler nicotinamide analogues could have driven early metabolic chemistry prebiotically.

Watch the video below to learn more.